Offline tile cache, polygon Divide, topographic layer integrations

Major feature batch covering drawing-tool improvements, layer additions, and offline-first capabilities. Largest changes in MapView.js (+1700), main.js (+1500), public/sw.js (+367), and new modules under src/. Drawing & editing toolkit * Polygon Divide tool — sub-button under Split, divides a polygon into N equal-area pieces via binary search; user picks the cutting edge * UPN pick phase after Split and Divide — non-picked pieces have their identifier fields cleared automatically * Improved Merge algorithm — vertex-to-edge proximity (5 m tol.) with hybrid lockstep extension; bold A/B labels on selected polygons * Persistent vertex highlights — all vertices of the selected polygon rendered as dots while edit mode is on, without subclassing ol-ext * Toast notifications for merge/split/divide outcomes * Shapefile import — addGeoJSONLayer now includes an image style so Point features render (previously invisible) Background & overlay layers * DEAfrica Coastlines v0.4 (WMS) in Biophysical Environment * DEAfrica Slope (SRTM 30m, style_slope) — semi-transparent background * Contours hillshade — get_contours_hillshade.php → local SQLite cache * OSM_roads — get_osm_roads.php → local SQLite cache, casing-stroke style (black 3.5 px outer, #F0F1F0 1.5 px inner) * External Source dialog — green + button in LayerSwitcher lets users add WMS / WFS / XYZ layers at runtime * Generic addWMSLayer / addXYZLayer with style, opacity, zIndex, legendUrl, onlineOnly options * TileWMS replaces ImageWMS (fixes 'Width exceeds 512' WMS errors) * Legend panel — bottom-right, auto-shown for visible layers that register a legendUrl * Default base map setting in Settings, persisted in localStorage; setBaseMap() on MapView Offline tile cache (Phase 1 + 2) * Service worker: per-host tile caches (osm / topo / satellite / carto-light / carto-dark), counter-based eviction to prevent iOS Safari memory-pressure reloads, GET_TILE_STATS / CLEAR_TILE_CACHES message API * pwa.js helpers: getActiveServiceWorker, onServiceWorkerControllerChange, getTileCacheStats, clearTileCaches, getStorageEstimate * Settings: Offline Map Tiles card with per-provider stats + clear * Phase 2 download dialog: form to pick base map, area (current view / district / Ghana), zoom range; live tile-count + size estimate; progress bar with cancel; OfflineTileDownloader class with concurrency + throttling Local database management * osm_roads table + saveOSMRoads / getLocalOSMRoads helpers * CACHED_LAYER_TABLES allow-list with clearTable / clearAllCachedLayers * Local Database Tables card: per-row Clear button (cached layers only) + 'Refresh cached layers' header button with reload prompt Build & infrastructure * Shpjs lazy-loaded via dynamic import (saves ~140 kB from initial JS) * chunkSizeWarningLimit raised to 900 kB (openlayers + sqlite3.wasm can't be split further) * Toast notification module (src/toast.js) * Units module (src/units.js) for metric / imperial conversions * PDF export module (src/pdf-export.js) Documentation & SQL * Topographic_Background_Layers_for_LUPMIS2.docx — research report * OpenTopography_Workflow.svg/.png — ETL pipeline diagram * LUPMIS2_Development_Status_Report.docx — April update section * sql/create_landuse_parcels.sql — PostgreSQL schema for the LUSPA land-use parcel specification (Feb 2026, revised), with PostGIS geometry column and standard indices Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-26 10:55:30 +02:00 · 2026-05-26 10:55:30 +02:00 · ef12e4477b
commit ef12e4477b
parent 3009a11b33
84 changed files with 10808 additions and 1499 deletions
--- a/LUPMIS2_Development_Status_Report.docx
+++ b/LUPMIS2_Development_Status_Report.docx
--- a/OpenTopography_Workflow.png
+++ b/OpenTopography_Workflow.png
--- a/OpenTopography_Workflow.svg
+++ b/OpenTopography_Workflow.svg
@ -0,0 +1,181 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 960 900" font-family="Arial, Helvetica, sans-serif">
+  <!-- ====================================================== -->
+  <!-- OpenTopography ETL Workflow for LUPMIS2                -->
+  <!-- A one-off data pipeline: download → process → serve    -->
+  <!-- ====================================================== -->
+
+  <defs>
+    <!-- Arrowhead -->
+    <marker id="arrow" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse">
+      <path d="M0,0 L10,5 L0,10 z" fill="#4b5563"/>
+    </marker>
+    <!-- Drop shadow -->
+    <filter id="shadow" x="-10%" y="-10%" width="120%" height="120%">
+      <feGaussianBlur in="SourceAlpha" stdDeviation="2"/>
+      <feOffset dx="1" dy="2"/>
+      <feComponentTransfer><feFuncA type="linear" slope="0.18"/></feComponentTransfer>
+      <feMerge><feMergeNode/><feMergeNode in="SourceGraphic"/></feMerge>
+    </filter>
+  </defs>
+
+  <!-- Background -->
+  <rect width="960" height="900" fill="#f9fafb"/>
+
+  <!-- Title -->
+  <text x="480" y="42" text-anchor="middle" font-size="22" font-weight="700" fill="#1e1a4b">
+    OpenTopography → LUPMIS2 Topographic Workflow
+  </text>
+  <text x="480" y="66" text-anchor="middle" font-size="13" fill="#6b7280">
+    One-off ETL pipeline: download DEM → generate products → serve to the PWA
+  </text>
+
+  <!-- ====================================================== -->
+  <!-- STAGE 1 — SOURCE (blue)                                -->
+  <!-- ====================================================== -->
+  <g filter="url(#shadow)">
+    <rect x="330" y="100" width="300" height="80" rx="10" ry="10" fill="#0ea5e9" stroke="#0369a1" stroke-width="1.5"/>
+  </g>
+  <text x="480" y="128" text-anchor="middle" font-size="15" font-weight="700" fill="#fff">OpenTopography API</text>
+  <text x="480" y="148" text-anchor="middle" font-size="12" fill="#e0f2fe">SRTM 30m / Copernicus 30m DEM</text>
+  <text x="480" y="166" text-anchor="middle" font-size="11" font-style="italic" fill="#bae6fd">API key required · 50 calls/24h (non-academic)</text>
+
+  <!-- Arrow 1 -->
+  <path d="M480,180 L480,220" stroke="#4b5563" stroke-width="2" fill="none" marker-end="url(#arrow)"/>
+  <text x="495" y="205" font-size="11" fill="#6b7280">one-off download · Ghana bbox ≈ 240,000 km²</text>
+
+  <!-- ====================================================== -->
+  <!-- STAGE 2 — RAW DATA (grey)                              -->
+  <!-- ====================================================== -->
+  <g filter="url(#shadow)">
+    <rect x="340" y="230" width="280" height="70" rx="10" ry="10" fill="#fff" stroke="#6b7280" stroke-width="1.5" stroke-dasharray="4,3"/>
+  </g>
+  <text x="480" y="258" text-anchor="middle" font-size="14" font-weight="700" fill="#1f2937">DEM GeoTIFF</text>
+  <text x="480" y="278" text-anchor="middle" font-size="12" fill="#4b5563">Ghana elevation raster (single file)</text>
+  <text x="480" y="294" text-anchor="middle" font-size="10" font-style="italic" fill="#6b7280">EPSG:4326 · ≈ 1 – 3 GB</text>
+
+  <!-- Split arrows -->
+  <path d="M480,300 L480,340 L230,340 L230,380" stroke="#4b5563" stroke-width="2" fill="none" marker-end="url(#arrow)"/>
+  <path d="M480,340 L730,340 L730,380" stroke="#4b5563" stroke-width="2" fill="none" marker-end="url(#arrow)"/>
+  <text x="420" y="332" text-anchor="end" font-size="11" fill="#6b7280">contours path</text>
+  <text x="540" y="332" font-size="11" fill="#6b7280">hillshade path</text>
+
+  <!-- ====================================================== -->
+  <!-- STAGE 3 — PROCESSING (green)                           -->
+  <!-- ====================================================== -->
+  <!-- Left: gdal_contour -->
+  <g filter="url(#shadow)">
+    <rect x="90" y="390" width="280" height="80" rx="10" ry="10" fill="#10b981" stroke="#047857" stroke-width="1.5"/>
+  </g>
+  <text x="230" y="418" text-anchor="middle" font-size="14" font-weight="700" fill="#fff">gdal_contour</text>
+  <text x="230" y="438" text-anchor="middle" font-size="11" fill="#d1fae5">extract contour polylines at fixed intervals</text>
+  <text x="230" y="456" text-anchor="middle" font-size="10" font-family="Menlo, monospace" fill="#ecfccb">-i 10 (10 m) or -i 20 (20 m)</text>
+
+  <!-- Right: gdaldem hillshade -->
+  <g filter="url(#shadow)">
+    <rect x="590" y="390" width="280" height="80" rx="10" ry="10" fill="#10b981" stroke="#047857" stroke-width="1.5"/>
+  </g>
+  <text x="730" y="418" text-anchor="middle" font-size="14" font-weight="700" fill="#fff">gdaldem hillshade</text>
+  <text x="730" y="438" text-anchor="middle" font-size="11" fill="#d1fae5">render shaded relief PNG</text>
+  <text x="730" y="456" text-anchor="middle" font-size="10" font-family="Menlo, monospace" fill="#ecfccb">-z 2 -az 315 -alt 45</text>
+
+  <!-- Arrows 3 → 4 -->
+  <path d="M230,470 L230,510" stroke="#4b5563" stroke-width="2" fill="none" marker-end="url(#arrow)"/>
+  <path d="M730,470 L730,510" stroke="#4b5563" stroke-width="2" fill="none" marker-end="url(#arrow)"/>
+
+  <!-- ====================================================== -->
+  <!-- STAGE 4 — DERIVATIVES (orange)                         -->
+  <!-- ====================================================== -->
+  <g filter="url(#shadow)">
+    <rect x="90" y="520" width="280" height="70" rx="10" ry="10" fill="#fff" stroke="#f59e0b" stroke-width="2"/>
+  </g>
+  <text x="230" y="548" text-anchor="middle" font-size="14" font-weight="700" fill="#92400e">Contour polylines</text>
+  <text x="230" y="568" text-anchor="middle" font-size="11" fill="#78350f">Shapefile / GeoPackage / GeoJSON</text>
+  <text x="230" y="584" text-anchor="middle" font-size="10" font-style="italic" fill="#b45309">vector</text>
+
+  <g filter="url(#shadow)">
+    <rect x="590" y="520" width="280" height="70" rx="10" ry="10" fill="#fff" stroke="#f59e0b" stroke-width="2"/>
+  </g>
+  <text x="730" y="548" text-anchor="middle" font-size="14" font-weight="700" fill="#92400e">Hillshade raster</text>
+  <text x="730" y="568" text-anchor="middle" font-size="11" fill="#78350f">GeoTIFF / PNG tile pyramid</text>
+  <text x="730" y="584" text-anchor="middle" font-size="10" font-style="italic" fill="#b45309">raster</text>
+
+  <!-- Arrows 4 → 5 -->
+  <path d="M230,590 L230,630" stroke="#4b5563" stroke-width="2" fill="none" marker-end="url(#arrow)"/>
+  <path d="M730,590 L730,630" stroke="#4b5563" stroke-width="2" fill="none" marker-end="url(#arrow)"/>
+
+  <!-- ====================================================== -->
+  <!-- STAGE 5 — SERVE (purple)                               -->
+  <!-- ====================================================== -->
+  <g filter="url(#shadow)">
+    <rect x="40" y="640" width="180" height="80" rx="10" ry="10" fill="#8b5cf6" stroke="#5b21b6" stroke-width="1.5"/>
+  </g>
+  <text x="130" y="668" text-anchor="middle" font-size="14" font-weight="700" fill="#fff">GeoServer</text>
+  <text x="130" y="688" text-anchor="middle" font-size="11" fill="#ede9fe">WMS endpoint</text>
+  <text x="130" y="706" text-anchor="middle" font-size="10" font-style="italic" fill="#ddd6fe">on-demand rendering</text>
+
+  <g filter="url(#shadow)">
+    <rect x="240" y="640" width="180" height="80" rx="10" ry="10" fill="#8b5cf6" stroke="#5b21b6" stroke-width="1.5"/>
+  </g>
+  <text x="330" y="668" text-anchor="middle" font-size="14" font-weight="700" fill="#fff">MBTiles</text>
+  <text x="330" y="688" text-anchor="middle" font-size="11" fill="#ede9fe">XYZ tile server</text>
+  <text x="330" y="706" text-anchor="middle" font-size="10" font-style="italic" fill="#ddd6fe">pre-rendered, fast</text>
+
+  <g filter="url(#shadow)">
+    <rect x="640" y="640" width="180" height="80" rx="10" ry="10" fill="#8b5cf6" stroke="#5b21b6" stroke-width="1.5"/>
+  </g>
+  <text x="730" y="668" text-anchor="middle" font-size="14" font-weight="700" fill="#fff">Tile pyramid</text>
+  <text x="730" y="688" text-anchor="middle" font-size="11" fill="#ede9fe">XYZ / WMTS</text>
+  <text x="730" y="706" text-anchor="middle" font-size="10" font-style="italic" fill="#ddd6fe">gdal2tiles.py</text>
+
+  <!-- Split arrow from contour derivatives to BOTH GeoServer and MBTiles -->
+  <path d="M180,610 L130,610 L130,640" stroke="#4b5563" stroke-width="2" fill="none" marker-end="url(#arrow)"/>
+  <path d="M280,610 L330,610 L330,640" stroke="#4b5563" stroke-width="2" fill="none" marker-end="url(#arrow)"/>
+  <path d="M230,590 L230,610" stroke="#4b5563" stroke-width="2" fill="none"/>
+  <line x1="130" y1="610" x2="330" y2="610" stroke="#4b5563" stroke-width="2"/>
+
+  <!-- Label the "OR" on the left side -->
+  <text x="230" y="627" text-anchor="middle" font-size="10" font-weight="700" fill="#6b7280">serve as WMS or XYZ</text>
+
+  <!-- Arrows 5 → 6 — converging to LUPMIS2 -->
+  <path d="M130,720 L130,770 L460,770 L460,800" stroke="#4b5563" stroke-width="2" fill="none" marker-end="url(#arrow)"/>
+  <path d="M330,720 L330,770" stroke="#4b5563" stroke-width="2" fill="none"/>
+  <line x1="330" y1="770" x2="460" y2="770" stroke="#4b5563" stroke-width="2"/>
+  <path d="M730,720 L730,770 L500,770 L500,800" stroke="#4b5563" stroke-width="2" fill="none" marker-end="url(#arrow)"/>
+
+  <!-- ====================================================== -->
+  <!-- STAGE 6 — CONSUMER (brand)                             -->
+  <!-- ====================================================== -->
+  <g filter="url(#shadow)">
+    <rect x="280" y="800" width="400" height="70" rx="10" ry="10" fill="#1e1a4b" stroke="#0f0c2a" stroke-width="1.5"/>
+  </g>
+  <text x="480" y="828" text-anchor="middle" font-size="15" font-weight="700" fill="#fff">LUPMIS2 PWA</text>
+  <text x="480" y="848" text-anchor="middle" font-size="11" fill="#c7d2fe">OpenLayers · addWMSLayer() / addXYZLayer()</text>
+  <text x="480" y="863" text-anchor="middle" font-size="10" font-style="italic" fill="#a5b4fc">"Biophysical Environment" group</text>
+
+  <!-- ====================================================== -->
+  <!-- LEGEND                                                 -->
+  <!-- ====================================================== -->
+  <g transform="translate(20,100)">
+    <rect width="140" height="180" rx="6" ry="6" fill="#fff" stroke="#d1d5db" stroke-width="1"/>
+    <text x="70" y="20" text-anchor="middle" font-size="12" font-weight="700" fill="#1f2937">Legend</text>
+    <rect x="10" y="32" width="20" height="14" rx="2" fill="#0ea5e9"/>
+    <text x="36" y="43" font-size="10" fill="#374151">External source</text>
+    <rect x="10" y="54" width="20" height="14" rx="2" fill="#fff" stroke="#6b7280" stroke-dasharray="3,2"/>
+    <text x="36" y="65" font-size="10" fill="#374151">Raw data file</text>
+    <rect x="10" y="76" width="20" height="14" rx="2" fill="#10b981"/>
+    <text x="36" y="87" font-size="10" fill="#374151">Processing step</text>
+    <rect x="10" y="98" width="20" height="14" rx="2" fill="#fff" stroke="#f59e0b" stroke-width="1.5"/>
+    <text x="36" y="109" font-size="10" fill="#374151">Derived product</text>
+    <rect x="10" y="120" width="20" height="14" rx="2" fill="#8b5cf6"/>
+    <text x="36" y="131" font-size="10" fill="#374151">Serving layer</text>
+    <rect x="10" y="142" width="20" height="14" rx="2" fill="#1e1a4b"/>
+    <text x="36" y="153" font-size="10" fill="#374151">Consumer</text>
+    <text x="70" y="172" text-anchor="middle" font-size="9" font-style="italic" fill="#6b7280">Run once · serve forever</text>
+  </g>
+
+  <!-- Footer note -->
+  <text x="480" y="888" text-anchor="middle" font-size="10" font-style="italic" fill="#6b7280">
+    Prepared for LUSPA · April 2026 · One-off ETL job — no runtime OpenTopography API calls from the PWA
+  </text>
+</svg>
--- a/Topographic_Background_Layers_for_LUPMIS2.docx
+++ b/Topographic_Background_Layers_for_LUPMIS2.docx
--- a/dist/assets/html2canvas.esm-B0tyYwQk.js
+++ b/dist/assets/html2canvas.esm-B0tyYwQk.js
--- a/dist/assets/html2canvas.esm-B0tyYwQk.js.map
+++ b/dist/assets/html2canvas.esm-B0tyYwQk.js.map
--- a/dist/assets/index-2WHoRhxp.js
+++ b/dist/assets/index-2WHoRhxp.js
--- a/dist/assets/index-2WHoRhxp.js.map
+++ b/dist/assets/index-2WHoRhxp.js.map
--- a/dist/assets/index-B4XzHtZX.js
+++ b/dist/assets/index-B4XzHtZX.js
--- a/dist/assets/index-B4XzHtZX.js.map
+++ b/dist/assets/index-B4XzHtZX.js.map
--- a/dist/assets/index.es-CRPDPo17.js
+++ b/dist/assets/index.es-CRPDPo17.js
--- a/dist/assets/index.es-CRPDPo17.js.map
+++ b/dist/assets/index.es-CRPDPo17.js.map
--- a/dist/assets/jspdf-Cu-2SCgw.js
+++ b/dist/assets/jspdf-Cu-2SCgw.js
--- a/dist/assets/jspdf-Cu-2SCgw.js.map
+++ b/dist/assets/jspdf-Cu-2SCgw.js.map
--- a/dist/assets/ol-ext-CSk2UikI.js
+++ b/dist/assets/ol-ext-CSk2UikI.js
--- a/dist/assets/ol-ext-CSk2UikI.js.map
+++ b/dist/assets/ol-ext-CSk2UikI.js.map
--- a/dist/assets/ol-ext-DytxBANR.js
+++ b/dist/assets/ol-ext-DytxBANR.js
--- a/dist/assets/ol-ext-DytxBANR.js.map
+++ b/dist/assets/ol-ext-DytxBANR.js.map
--- a/dist/assets/openlayers-CUDtI0S3.js
+++ b/dist/assets/openlayers-CUDtI0S3.js
--- a/dist/assets/openlayers-CUDtI0S3.js.map
+++ b/dist/assets/openlayers-CUDtI0S3.js.map
--- a/dist/assets/openlayers-D2I-bVN2.js
+++ b/dist/assets/openlayers-D2I-bVN2.js
--- a/dist/assets/openlayers-D2I-bVN2.js.map
+++ b/dist/assets/openlayers-D2I-bVN2.js.map
--- a/dist/assets/pdf-export-Vpiz8VA4.js
+++ b/dist/assets/pdf-export-Vpiz8VA4.js
@ -0,0 +1,2 @@
+import{E as f,a as b}from"./jspdf-Cu-2SCgw.js";import"./openlayers-CUDtI0S3.js";b(f);let s=null;async function x(){if(s)return s;try{const e=new Image;e.crossOrigin="anonymous",await new Promise((r,i)=>{e.onload=r,e.onerror=i,e.src="./icons/luspa-pdf.jpg"});const n=document.createElement("canvas");n.width=e.naturalWidth,n.height=e.naturalHeight;const t=n.getContext("2d");return t.fillStyle="#ffffff",t.fillRect(0,0,n.width,n.height),t.drawImage(e,0,0),s=n.toDataURL("image/jpeg",.92),s}catch(e){return console.warn("[PDF] Could not load logo:",e),null}}async function v({title:e,rows:n}){const t=new f({orientation:"portrait",unit:"mm",format:"a4"}),r=t.internal.pageSize.getWidth(),i=[30,26,75],g=await x(),c=28,a=14;let o=14;g&&t.addImage(g,"JPEG",a,o,c,c);const m=a+c+6;t.setFont("helvetica","bold"),t.setFontSize(18),t.setTextColor(...i),t.text("LUPMIS",m,o+11),t.setFont("helvetica","normal"),t.setFontSize(12),t.text(e,m,o+19);const d=new Date,h=d.toLocaleDateString(void 0,{year:"numeric",month:"long",day:"numeric"}),y=d.toLocaleTimeString([],{hour:"2-digit",minute:"2-digit"});t.setFontSize(9),t.setTextColor(120,120,120),t.text(`${h}  ${y}`,r-a,o+11,{align:"right"}),o+=c+6,t.setDrawColor(...i),t.setLineWidth(.5),t.line(a,o,r-a,o),o+=6;const S=n.map(l=>[l.label,l.value]);t.autoTable({startY:o,head:[["Property","Value"]],body:S,margin:{left:a,right:a},styles:{font:"helvetica",fontSize:10,cellPadding:4},headStyles:{fillColor:i,textColor:[255,255,255],fontStyle:"bold"},alternateRowStyles:{fillColor:[245,245,250]},columnStyles:{0:{fontStyle:"bold",cellWidth:50}}});const p=t.lastAutoTable.finalY+10;t.setFontSize(8),t.setTextColor(160,160,160),t.text("Generated by LUPMIS2 Land Use Planning & Management Information System",a,p);const w=t.output("blob"),u=URL.createObjectURL(w);if(!window.open(u,"_blank")){const l=document.createElement("a");l.href=u,l.download=`${e.replace(/\s+/g,"_")}_${d.toISOString().slice(0,10)}.pdf`,document.body.appendChild(l),l.click(),document.body.removeChild(l)}}export{v as exportAnalysisPDF};
+//# sourceMappingURL=pdf-export-Vpiz8VA4.js.map
--- a/dist/assets/pdf-export-Vpiz8VA4.js.map
+++ b/dist/assets/pdf-export-Vpiz8VA4.js.map
--- a/dist/assets/purify.es-BgtpMKW3.js
+++ b/dist/assets/purify.es-BgtpMKW3.js
--- a/dist/assets/purify.es-BgtpMKW3.js.map
+++ b/dist/assets/purify.es-BgtpMKW3.js.map
--- a/dist/assets/shpjs-CNrRgkgn.js
+++ b/dist/assets/shpjs-CNrRgkgn.js
--- a/dist/assets/shpjs-CNrRgkgn.js.map
+++ b/dist/assets/shpjs-CNrRgkgn.js.map
--- a/dist/fonts/bebas-neue-latin-ext.woff2
+++ b/dist/fonts/bebas-neue-latin-ext.woff2
--- a/dist/fonts/bebas-neue-latin.woff2
+++ b/dist/fonts/bebas-neue-latin.woff2
--- a/dist/fonts/exo-latin-ext.woff2
+++ b/dist/fonts/exo-latin-ext.woff2
--- a/dist/fonts/exo-latin.woff2
+++ b/dist/fonts/exo-latin.woff2
--- a/dist/fonts/exo-vietnamese.woff2
+++ b/dist/fonts/exo-vietnamese.woff2
--- a/dist/icons/README.txt
+++ b/dist/icons/README.txt
@ -1 +0,0 @@
-Place PWA icons here (icon-72.png, icon-96.png, icon-128.png, icon-144.png, icon-152.png, icon-192.png, icon-384.png, icon-512.png)
--- a/dist/icons/luspa-128x128.png
+++ b/dist/icons/luspa-128x128.png
--- a/dist/icons/luspa-144x144.png
+++ b/dist/icons/luspa-144x144.png
--- a/dist/icons/luspa-152x152.png
+++ b/dist/icons/luspa-152x152.png
--- a/dist/icons/luspa-384x384.png
+++ b/dist/icons/luspa-384x384.png
--- a/dist/icons/luspa-72x72.png
+++ b/dist/icons/luspa-72x72.png
--- a/dist/icons/luspa-96x96.png
+++ b/dist/icons/luspa-96x96.png
--- a/dist/icons/luspa-pdf.jpg
+++ b/dist/icons/luspa-pdf.jpg
--- a/dist/index.html
+++ b/dist/index.html
@ -2,19 +2,64 @@
 <html lang="en" data-bs-theme="light">
 <head>
  <meta charset="UTF-8">
-  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0, viewport-fit=cover">
  <meta name="theme-color" content="#005eb8">
  <meta name="description" content="LUPMIS2 Drawing Tools">

  <!-- PWA Manifest -->
-  <link rel="manifest" href="/manifest.json">
-  <link rel="apple-touch-icon" href="/icons/luspa.icon">
-  <link rel="icon" href="/icons/luspa.icon">
+  <link rel="manifest" href="manifest.json">
+  <link rel="apple-touch-icon" sizes="192x192" href="icons/luspa-192x192.png">
+  <link rel="icon" type="image/png" sizes="32x32" href="icons/luspa-32x32.png">
+  <link rel="icon" type="image/png" sizes="16x16" href="icons/luspa-16x16.png">

-  <!-- LUSPA Design System Fonts: Bebas Neue (display) + Exo (body) -->
-  <link rel="preconnect" href="https://fonts.googleapis.com">
-  <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
-  <link href="https://fonts.googleapis.com/css2?family=Bebas+Neue&family=Exo:wght@300;400;500;600;700;800&display=swap" rel="stylesheet">
+  <!-- LUSPA Design System Fonts: Bebas Neue (display) + Exo (body) — self-hosted -->
+  <style>
+    /* Bebas Neue 400 — latin-ext */
+    @font-face {
+      font-family: 'Bebas Neue';
+      font-style: normal;
+      font-weight: 400;
+      font-display: swap;
+      src: url('/fonts/bebas-neue-latin-ext.woff2') format('woff2');
+      unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
+    }
+    /* Bebas Neue 400 — latin */
+    @font-face {
+      font-family: 'Bebas Neue';
+      font-style: normal;
+      font-weight: 400;
+      font-display: swap;
+      src: url('/fonts/bebas-neue-latin.woff2') format('woff2');
+      unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
+    }
+    /* Exo 300-800 — vietnamese */
+    @font-face {
+      font-family: 'Exo';
+      font-style: normal;
+      font-weight: 300 800;
+      font-display: swap;
+      src: url('/fonts/exo-vietnamese.woff2') format('woff2');
+      unicode-range: U+0102-0103, U+0110-0111, U+0128-0129, U+0168-0169, U+01A0-01A1, U+01AF-01B0, U+0300-0301, U+0303-0304, U+0308-0309, U+0323, U+0329, U+1EA0-1EF9, U+20AB;
+    }
+    /* Exo 300-800 — latin-ext */
+    @font-face {
+      font-family: 'Exo';
+      font-style: normal;
+      font-weight: 300 800;
+      font-display: swap;
+      src: url('/fonts/exo-latin-ext.woff2') format('woff2');
+      unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
+    }
+    /* Exo 300-800 — latin */
+    @font-face {
+      font-family: 'Exo';
+      font-style: normal;
+      font-weight: 300 800;
+      font-display: swap;
+      src: url('/fonts/exo-latin.woff2') format('woff2');
+      unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
+    }
+  </style>

  <title>LUPMIS2 Drawing Tools</title>

@ -106,6 +151,295 @@
      --radius-2xl: 1rem;
    }

+    /* ─── Fieldwork Mode ─── high-contrast + larger touch targets ─── */
+    .fieldwork-mode {
+      --foreground: #000;
+      --background: #fff;
+      --card: #fff;
+      --card-foreground: #000;
+      --primary: #0044aa;
+      --primary-foreground: #fff;
+      --primary-hover: #003080;
+      --muted: #e0e0e0;
+      --muted-foreground: #333;
+      --accent: #cce0ff;
+      --accent-foreground: #000;
+      --border: rgba(0,0,0,0.25);
+      --success: #005a00;
+      --success-foreground: #fff;
+      --warning: #b36b00;
+      --warning-foreground: #000;
+      --destructive: #b80000;
+      --destructive-foreground: #fff;
+      --ring: #0044aa;
+      --bs-body-color: #000;
+    }
+
+    /* Fieldwork: larger dock buttons */
+    .fieldwork-mode .dock-btn {
+      min-width: 72px;
+      min-height: 58px;
+      font-size: 1.6rem;
+      border-width: 2px;
+    }
+    .fieldwork-mode .dock-btn-label {
+      font-size: 0.75rem;
+      font-weight: 600;
+    }
+
+    /* Fieldwork: bolder navbar */
+    .fieldwork-mode .navbar {
+      border-bottom-width: 4px;
+    }
+    .fieldwork-mode .navbar .navbar-brand {
+      font-size: 1.6rem;
+    }
+
+    /* Fieldwork: larger offcanvas toggle buttons */
+    .fieldwork-mode .offcanvas-toggle {
+      width: 44px;
+      height: 44px;
+      font-size: 1.2rem;
+    }
+
+    /* Fieldwork: thicker bottom dock border */
+    .fieldwork-mode .bottom-dock {
+      border-top-width: 4px;
+    }
+
+    /* Fieldwork: larger text in cards / lists */
+    .fieldwork-mode .card-header h6 {
+      font-size: 1rem;
+    }
+    .fieldwork-mode .list-group-item {
+      font-size: 0.95rem;
+      padding: 0.65rem 1rem;
+    }
+
+    /* Fieldwork: larger buttons globally */
+    .fieldwork-mode .btn {
+      font-size: 0.95rem;
+      padding: 0.5rem 1rem;
+      font-weight: 600;
+    }
+    .fieldwork-mode .btn-sm {
+      font-size: 0.85rem;
+      padding: 0.4rem 0.75rem;
+    }
+
+    /* Fieldwork: stronger borders on inputs / form controls */
+    .fieldwork-mode .form-control,
+    .fieldwork-mode .form-select {
+      border-width: 2px;
+      border-color: #555;
+      font-size: 1rem;
+    }
+
+    /* Fieldwork: bolder map controls (ol-ext) */
+    .fieldwork-mode .ol-control button {
+      font-size: 1.3rem;
+      width: 2.2em;
+      height: 2.2em;
+    }
+
+    /* Fieldwork: scale bar text legibility */
+    .fieldwork-mode .ol-scale-bar .ol-scale-step-text,
+    .fieldwork-mode .ol-scale-bar .ol-scale-text {
+      font-size: 12px;
+      font-weight: 700;
+      text-shadow: 0 0 4px #fff, 0 0 8px #fff;
+    }
+
+    /* ─── Dark Mode ─── reversed colour scheme ─── */
+    .dark-mode {
+      --foreground: #e0dff0;
+      --background: #131325;
+      --card: #1e1e38;
+      --card-foreground: #e0dff0;
+      --primary: #4d9de6;
+      --primary-foreground: #fff;
+      --primary-hover: #6fb3f0;
+      --muted: #272745;
+      --muted-foreground: #9594a8;
+      --accent: #1e3a5f;
+      --accent-foreground: #e0dff0;
+      --border: rgba(255,255,255,0.12);
+      --ring: #4d9de6;
+      --success: #2dd46a;
+      --success-foreground: #131325;
+      --warning: #ffb84d;
+      --warning-foreground: #131325;
+      --destructive: #f04040;
+      --destructive-foreground: #fff;
+      --bs-body-color: #e0dff0;
+      --bs-body-bg: #131325;
+      --bs-tertiary-bg: #1e1e38;
+      color-scheme: dark;
+    }
+
+    /* Dark: navbar */
+    .dark-mode .navbar {
+      background-color: #1a1a30 !important;
+      box-shadow: 0 1px 6px rgba(0,0,0,0.4);
+    }
+
+    /* Dark: bottom dock */
+    .dark-mode .bottom-dock {
+      background-color: #1a1a30;
+      box-shadow: 0 -2px 10px rgba(0,0,0,0.3);
+    }
+    .dark-mode .dock-btn {
+      border-color: var(--primary);
+      color: var(--foreground);
+    }
+    .dark-mode .dock-btn:hover {
+      background-color: var(--muted);
+    }
+    .dark-mode .dock-btn.active {
+      background-color: var(--primary);
+      color: var(--primary-foreground);
+    }
+
+    /* Dark: offcanvas panels */
+    .dark-mode .offcanvas {
+      background-color: var(--background) !important;
+      color: var(--foreground) !important;
+    }
+    .dark-mode .offcanvas-header {
+      border-bottom-color: var(--border) !important;
+    }
+    .dark-mode .btn-close {
+      filter: invert(1) grayscale(100%) brightness(200%);
+    }
+
+    /* Dark: cards */
+    .dark-mode .card {
+      background-color: var(--card) !important;
+      color: var(--card-foreground) !important;
+      border-color: var(--border) !important;
+    }
+
+    /* Dark: offcanvas toggle buttons */
+    .dark-mode .offcanvas-toggle {
+      background-color: var(--card);
+      color: var(--foreground);
+      border-color: var(--border);
+    }
+    .dark-mode .offcanvas-toggle:hover {
+      background-color: var(--primary);
+      color: var(--primary-foreground);
+    }
+
+    /* Dark: form controls */
+    .dark-mode .form-control,
+    .dark-mode .form-select {
+      background-color: var(--muted) !important;
+      color: var(--foreground) !important;
+      border-color: var(--border) !important;
+    }
+    .dark-mode .form-check-input {
+      background-color: var(--muted);
+      border-color: var(--muted-foreground);
+    }
+    .dark-mode .form-check-input:checked {
+      background-color: var(--primary);
+      border-color: var(--primary);
+    }
+
+    /* Dark: list groups */
+    .dark-mode .list-group-item {
+      background-color: var(--card) !important;
+      color: var(--card-foreground) !important;
+      border-color: var(--border) !important;
+    }
+
+    /* Dark: buttons */
+    .dark-mode .btn-outline-primary {
+      color: var(--primary);
+      border-color: var(--primary);
+    }
+    .dark-mode .btn-outline-danger {
+      color: var(--destructive);
+      border-color: var(--destructive);
+    }
+
+    /* Dark: text utilities */
+    .dark-mode .text-muted {
+      color: var(--muted-foreground) !important;
+    }
+
+    /* Dark: measurement tooltips */
+    .dark-mode .measure-tooltip {
+      background: rgba(30, 30, 56, 0.95);
+      color: var(--foreground);
+      border-color: var(--primary);
+    }
+    .dark-mode .measure-tooltip::before {
+      border-right-color: var(--primary);
+    }
+
+    /* Dark: OL controls */
+    .dark-mode .ol-control button {
+      background-color: var(--card) !important;
+      color: var(--foreground) !important;
+    }
+    .dark-mode .ol-control button:hover {
+      background-color: var(--primary) !important;
+      color: var(--primary-foreground) !important;
+    }
+    .dark-mode .ol-attribution,
+    .dark-mode .ol-attribution a {
+      color: var(--muted-foreground) !important;
+    }
+
+    /* Dark: scale bar */
+    .dark-mode .ol-scale-bar .ol-scale-step-text,
+    .dark-mode .ol-scale-bar .ol-scale-text {
+      color: #fff !important;
+      text-shadow: 0 0 4px #000, 0 0 8px #000 !important;
+    }
+    .dark-mode .ol-scale-bar .ol-scale-singlebar-even {
+      background-color: #fff !important;
+    }
+    .dark-mode .ol-scale-bar .ol-scale-singlebar-odd {
+      background-color: #999 !important;
+    }
+
+    /* Dark: map drop overlay */
+    .dark-mode .map-drop-overlay {
+      background: rgba(19, 19, 37, 0.85);
+      border-color: var(--primary);
+      color: var(--foreground);
+    }
+
+    /* Dark: ol-ext LayerSwitcher */
+    .dark-mode .ol-layerswitcher {
+      background-color: var(--card) !important;
+    }
+    .dark-mode .ol-layerswitcher .panel {
+      background-color: var(--card) !important;
+      color: var(--foreground) !important;
+    }
+    .dark-mode .ol-layerswitcher .panel li {
+      color: var(--foreground);
+    }
+    .dark-mode .ol-layerswitcher .ol-switchertopdiv,
+    .dark-mode .ol-layerswitcher .ol-switcherbottomdiv {
+      background: var(--card) !important;
+    }
+
+    /* Dark: alert boxes */
+    .dark-mode .alert-danger {
+      background-color: rgba(240, 64, 64, 0.15) !important;
+      color: var(--destructive) !important;
+      border-color: var(--destructive) !important;
+    }
+    .dark-mode .alert-success {
+      background-color: rgba(45, 212, 106, 0.15) !important;
+      color: var(--success) !important;
+      border-color: var(--success) !important;
+    }
+
    /* Full height layout */
    html, body {
      height: 100%;
@ -214,9 +548,12 @@
      font-family: var(--font-body);
    }

-    /* Main container - full height */
+    /* Main container - full height.
+       100dvh accounts for mobile browser chrome and OS nav bars.
+       Falls back to 100vh for older browsers. */
    .app-container {
      height: 100vh;
+      height: 100dvh;
      display: flex;
      flex-direction: column;
    }
@ -244,6 +581,35 @@
      height: 100%;
    }

+    /* Drag-and-drop overlay shown when files are dragged over the map */
+    .map-drop-overlay {
+      position: absolute;
+      inset: 0;
+      z-index: 9999;
+      display: flex;
+      align-items: center;
+      justify-content: center;
+      background: rgba(0, 94, 184, 0.15);
+      border: 3px dashed var(--primary, #005eb8);
+      border-radius: 8px;
+      pointer-events: none;
+      opacity: 0;
+      transition: opacity 0.15s ease;
+    }
+    .map-container.drag-over .map-drop-overlay {
+      opacity: 1;
+    }
+    .map-drop-overlay span {
+      font-family: var(--font-body, 'Exo', sans-serif);
+      font-size: 1.15rem;
+      font-weight: 600;
+      color: var(--primary, #005eb8);
+      background: var(--card, #fff);
+      padding: 0.6rem 1.4rem;
+      border-radius: 6px;
+      box-shadow: 0 2px 8px rgba(0,0,0,0.12);
+    }
+
    /* Offline indicator */
    #offline-indicator {
      display: none;
@ -301,9 +667,14 @@
      z-index: 1050;
    }

-    /* Fix ol-ext LayerSwitcher z-index */
-    .ol-layerswitcher {
-      z-index: 100;
+    /* OL controls stacking context fix — OpenLayers sets z-index:0 on
+       .ol-overlaycontainer-stopevent, trapping all controls below the
+       offcanvas-toggle buttons (z-index:500).  Raising the container
+       to 501 lets the LayerSwitcher dropdown render above the toggles.
+       pointer-events:none on the container still lets clicks through
+       to the toggle buttons underneath. */
+    .ol-overlaycontainer-stopevent {
+      z-index: 501 !important;
    }

    /* Alert hint box */
@ -419,7 +790,7 @@
    }

    .offcanvas-toggle-bottom {
-      bottom: 80px; /* Above the dock */
+      bottom: calc(80px + env(safe-area-inset-bottom, 0px)); /* Above the dock */
      left: 50%;
      transform: translateX(-50%);
    }
@ -432,7 +803,10 @@
      transform: translateX(-50%) scale(0.95);
    }

-    /* Bottom Dock — white card style with blue-strong accent */
+    /* Bottom Dock — white card style with blue-strong accent.
+       env(safe-area-inset-bottom) adds padding on devices with a
+       home indicator / gesture bar (e.g. iPhone notch models).
+       The value is 0 on devices without an inset. */
    .bottom-dock {
      position: absolute;
      bottom: 0;
@ -441,7 +815,7 @@
      z-index: 600;
      background-color: var(--card);
      border-top: 3px solid var(--primary);
-      padding: 8px 16px;
+      padding: 8px 16px calc(8px + env(safe-area-inset-bottom, 0px));
      display: flex;
      justify-content: space-around;
      align-items: center;
@ -503,6 +877,13 @@
      justify-content: center;
    }

+    /* Snap-guides toggle — highlighted when active */
+    .ol-snap-toggle.ol-active button {
+      background: var(--primary) !important;
+      color: var(--primary-foreground, #fff) !important;
+      border-radius: 3px;
+    }
+
    /* Touch-friendly improvements for forms and buttons */
    .form-control, .form-select {
      min-height: 44px;
@ -541,6 +922,18 @@
      color: var(--foreground);
    }

+    /* Message log in the right panel */
+    .message-log {
+      max-height: 260px;
+      overflow-y: auto;
+    }
+
+    .message-log-entry {
+      font-size: 0.82rem;
+      border-color: var(--border, #eee) !important;
+      background: transparent;
+    }
+
    /* ol-ext GeolocationButton styling */
    .ol-geobt {
      top: auto !important;
@ -830,6 +1223,7 @@
    /* Locations list in offcanvas - can be taller now without form */
    .offcanvas-end .locations-list {
      max-height: calc(100vh - 280px);
+      max-height: calc(100dvh - 280px);
      overflow-y: auto;
    }

@ -921,17 +1315,32 @@
      font-size: 18px;
    }

-    /* ScaleLine - position above the bottom dock */
-    .ol-scale-line {
-      bottom: 76px !important;
+    /* ScaleBar - position above the bottom dock with 4px gap */
+    .ol-scale-bar {
+      bottom: calc(85px + env(safe-area-inset-bottom, 0px)) !important;
      left: 10px !important;
    }

-    .ol-scale-line-inner {
-      border-color: var(--foreground) !important;
+    .ol-scale-bar .ol-scale-step-text {
      color: var(--foreground) !important;
      font-family: var(--font-body) !important;
      font-size: 11px !important;
+      text-shadow: 0 0 3px var(--background), 0 0 6px var(--background) !important;
+    }
+
+    .ol-scale-bar .ol-scale-text {
+      color: var(--foreground) !important;
+      font-family: var(--font-body) !important;
+      font-size: 11px !important;
+      text-shadow: 0 0 3px var(--background), 0 0 6px var(--background) !important;
+    }
+
+    .ol-scale-bar .ol-scale-singlebar-even {
+      background-color: var(--foreground) !important;
+    }
+
+    .ol-scale-bar .ol-scale-singlebar-odd {
+      background-color: var(--muted-foreground) !important;
    }

    /* ol-ext Bar overrides */
@ -950,12 +1359,12 @@
      gap: 2px;
    }
  </style>
-  <script type="module" crossorigin src="/assets/index-2WHoRhxp.js"></script>
+  <script type="module" crossorigin src="/assets/index-B4XzHtZX.js"></script>
+  <link rel="modulepreload" crossorigin href="/assets/openlayers-CUDtI0S3.js">
  <link rel="modulepreload" crossorigin href="/assets/bootstrap-D1-uvFxm.js">
-  <link rel="modulepreload" crossorigin href="/assets/openlayers-D2I-bVN2.js">
-  <link rel="modulepreload" crossorigin href="/assets/ol-ext-DytxBANR.js">
-  <link rel="stylesheet" crossorigin href="/assets/bootstrap-BtmJYOxZ.css">
+  <link rel="modulepreload" crossorigin href="/assets/ol-ext-CSk2UikI.js">
  <link rel="stylesheet" crossorigin href="/assets/openlayers-BtPuoxOl.css">
+  <link rel="stylesheet" crossorigin href="/assets/bootstrap-BtmJYOxZ.css">
  <link rel="stylesheet" crossorigin href="/assets/ol-ext-BgKrOIxx.css">
  <link rel="stylesheet" crossorigin href="/assets/index-BnwqsTiD.css">
 </head>
@ -988,6 +1397,7 @@
          </span>
        </div>
        <div id="map"></div>
+        <div class="map-drop-overlay"><span><i class="bi bi-file-earmark-arrow-up me-2"></i>Drop file to import (.shp .geojson .kml)</span></div>

        <!-- Offcanvas toggle buttons -->
        <button class="offcanvas-toggle offcanvas-toggle-left"
@ -1112,17 +1522,40 @@
      <button type="button" class="btn btn-outline-primary w-100 mb-3" id="local-data-btn">
        <i class="bi bi-database me-2"></i>Local Data
      </button>
+      <button type="button" class="btn btn-outline-primary w-100 mb-3" id="import-shp-btn">
+        <i class="bi bi-file-earmark-arrow-up me-2"></i>Import .shp
+      </button>
+      <input type="file" id="shp-file-input" accept=".zip,.shp,.dbf,.shx,.prj" multiple class="d-none">
+      <button type="button" class="btn btn-outline-primary w-100 mb-3" id="import-geojson-btn">
+        <i class="bi bi-file-earmark-arrow-up me-2"></i>Import GeoJSON
+      </button>
+      <input type="file" id="geojson-file-input" accept=".geojson,.json" class="d-none">
+      <button type="button" class="btn btn-outline-primary w-100 mb-3" id="import-kml-btn">
+        <i class="bi bi-file-earmark-arrow-up me-2"></i>Import KML
+      </button>
+      <input type="file" id="kml-file-input" accept=".kml,.kmz" class="d-none">
+      <div id="file-import-alert" class="alert alert-danger alert-dismissible fade show d-none mb-3" role="alert">
+        <small class="message-text"></small>
+        <button type="button" class="btn-close btn-close-sm" data-bs-dismiss="alert" aria-label="Close"></button>
+      </div>
+      <div id="imported-layers-info" class="d-none mb-3"></div>
      <div id="local-data-stats" class="d-none">
        <div class="card">
-          <div class="card-header bg-primary py-2">
+          <div class="card-header bg-primary py-2 d-flex justify-content-between align-items-center">
            <h6 class="mb-0"><i class="bi bi-database me-2"></i>Local Database Tables</h6>
+            <button type="button" class="btn btn-sm btn-outline-light"
+                    id="clear-all-cached-btn"
+                    title="Delete all cached map layers. They will be re-downloaded on next app start.">
+              <i class="bi bi-arrow-clockwise me-1"></i>Refresh cached layers
+            </button>
          </div>
          <div class="card-body p-0">
            <table class="table table-sm table-striped mb-0">
              <thead>
                <tr>
                  <th class="ps-3">Table</th>
-                  <th class="text-end pe-3">Records</th>
+                  <th class="text-end">Records</th>
+                  <th class="text-end pe-3" style="width:3rem;"></th>
                </tr>
              </thead>
              <tbody id="local-data-tbody">
@ -1150,6 +1583,10 @@
            <span class="message-text"></span>
            <button type="button" class="btn-close" data-bs-dismiss="alert" aria-label="Close"></button>
          </div>
+          <div id="warning-message" class="alert alert-warning alert-dismissible fade show d-none" role="alert">
+            <span class="message-text"></span>
+            <button type="button" class="btn-close" data-bs-dismiss="alert" aria-label="Close"></button>
+          </div>

      <!-- Tip -->
          <div class="alert alert-light border-start border-4 border-primary py-2 mb-3" role="alert">
@ -1189,20 +1626,268 @@
              </div>
            </div>
          </div>
+
+          <!-- Message Log -->
+          <div class="card mt-3" id="message-log-card">
+            <div class="card-header bg-transparent py-2 d-flex justify-content-between align-items-center">
+              <h6 class="mb-0" style="font-family:var(--font-body);font-weight:700;"><i class="bi bi-journal-text me-1"></i> Messages</h6>
+              <button class="btn btn-sm btn-link text-muted p-0" id="clear-message-log" title="Clear messages">
+                <i class="bi bi-trash3"></i>
+              </button>
+            </div>
+            <div class="card-body p-0">
+              <div id="message-log" class="message-log list-group list-group-flush">
+                <div class="text-center text-muted py-3">
+                  <small>No messages yet.</small>
+                </div>
+              </div>
+            </div>
+          </div>
+
        </div>
    </div>

  <!-- Bottom Offcanvas -->
  <div class="offcanvas offcanvas-bottom" tabindex="-1" id="offcanvasBottom" aria-labelledby="offcanvasBottomLabel">
    <div class="offcanvas-header">
-      <h5 class="offcanvas-title" id="offcanvasBottomLabel"><i class="bi bi-chevron-down me-2"></i>Bottom Panel</h5>
+      <h5 class="offcanvas-title" id="offcanvasBottomLabel"><i class="bi bi-gear me-2"></i>Settings</h5>
      <button type="button" class="btn-close" data-bs-dismiss="offcanvas" aria-label="Close"></button>
-        </div>
+    </div>
    <div class="offcanvas-body">
-      <p>This is the bottom offcanvas panel.</p>
-      <p>You can add a data table, charts, or other wide content here.</p>
+      <div class="row g-3">
+        <!-- Fieldwork Mode -->
+        <div class="col-12 col-md-6 col-lg-4">
+          <div class="card">
+            <div class="card-body">
+              <div class="d-flex align-items-center justify-content-between">
+                <div>
+                  <h6 class="mb-1" style="font-family:var(--font-body);font-weight:700;">Fieldwork Mode</h6>
+                  <small class="text-muted">High-contrast colours and larger touch targets for bright sunlight and field conditions.</small>
+                </div>
+                <div class="form-check form-switch ms-3">
+                  <input class="form-check-input" type="checkbox" role="switch" id="fieldwork-mode-toggle" style="width:3rem;height:1.5rem;cursor:pointer;">
+                </div>
              </div>
            </div>
+          </div>
+        </div>
+        <!-- Dark Mode -->
+        <div class="col-12 col-md-6 col-lg-4">
+          <div class="card">
+            <div class="card-body">
+              <div class="d-flex align-items-center justify-content-between">
+                <div>
+                  <h6 class="mb-1" style="font-family:var(--font-body);font-weight:700;">Dark Mode</h6>
+                  <small class="text-muted">Reduce glare and save battery with a dark colour scheme.</small>
+                </div>
+                <div class="form-check form-switch ms-3">
+                  <input class="form-check-input" type="checkbox" role="switch" id="dark-mode-toggle" style="width:3rem;height:1.5rem;cursor:pointer;">
+                </div>
+              </div>
+            </div>
+          </div>
+        </div>
+        <!-- Measurement System -->
+        <div class="col-12 col-md-6 col-lg-4">
+          <div class="card">
+            <div class="card-body">
+              <div class="d-flex align-items-center justify-content-between">
+                <div>
+                  <h6 class="mb-1" style="font-family:var(--font-body);font-weight:700;">Measurement System</h6>
+                  <small class="text-muted">Switch between Metric (m, km) and Imperial (ft, mi, acres) units.</small>
+                </div>
+                <div class="form-check form-switch ms-3">
+                  <input class="form-check-input" type="checkbox" role="switch" id="measurement-system-toggle" style="width:3rem;height:1.5rem;cursor:pointer;">
+                  <label class="form-check-label ms-1" id="measurement-system-label" for="measurement-system-toggle" style="font-size:0.8rem;font-weight:600;min-width:55px;">Metric</label>
+                </div>
+              </div>
+            </div>
+          </div>
+        </div>
+        <!-- Default Base Map -->
+        <div class="col-12 col-md-6 col-lg-4">
+          <div class="card">
+            <div class="card-body">
+              <div class="d-flex align-items-center justify-content-between">
+                <div style="flex:1;min-width:0;">
+                  <h6 class="mb-1" style="font-family:var(--font-body);font-weight:700;">Default Base Map</h6>
+                  <small class="text-muted">Base map shown on app start. Saved on this device.</small>
+                </div>
+                <div class="ms-3" style="min-width:140px;">
+                  <select class="form-select form-select-sm" id="default-basemap-select" aria-label="Default base map">
+                    <option value="topo">Topographic</option>
+                    <option value="osm">OpenStreetMap</option>
+                    <option value="satellite">Satellite</option>
+                    <option value="googlesat">Google Sat</option>
+                    <option value="carto-light">Carto Light</option>
+                    <option value="carto-dark">Carto Dark</option>
+                  </select>
+                </div>
+              </div>
+            </div>
+          </div>
+        </div>
+        <!-- Offline Map Tiles -->
+        <div class="col-12 col-md-6 col-lg-8">
+          <div class="card">
+            <div class="card-body">
+              <div class="d-flex align-items-start justify-content-between mb-2">
+                <div style="flex:1;min-width:0;">
+                  <h6 class="mb-1" style="font-family:var(--font-body);font-weight:700;">
+                    <i class="bi bi-map me-1"></i>Offline Map Tiles
+                  </h6>
+                  <small class="text-muted">
+                    Map tiles you've already viewed are cached on this device so they work offline.
+                    Tiles are cached automatically as you browse, or you can pre-download a region.
+                  </small>
+                </div>
+                <div class="ms-3 d-flex gap-2 flex-shrink-0">
+                  <button type="button" class="btn btn-sm btn-primary"
+                          id="download-tiles-btn" style="white-space:nowrap;">
+                    <i class="bi bi-cloud-download me-1"></i>Download offline map
+                  </button>
+                  <button type="button" class="btn btn-sm btn-outline-danger"
+                          id="clear-tiles-btn" style="white-space:nowrap;">
+                    <i class="bi bi-trash3 me-1"></i>Clear cached tiles
+                  </button>
+                </div>
+              </div>
+              <div id="tile-cache-stats" class="small">
+                <div class="text-muted fst-italic">Loading…</div>
+              </div>
+            </div>
+          </div>
+        </div>
+      </div>
+    </div>
+  </div>
+
+  <!-- Download Offline Map modal -->
+  <div class="modal fade" id="offline-download-modal" tabindex="-1" aria-labelledby="offline-download-title" aria-hidden="true">
+    <div class="modal-dialog modal-dialog-centered modal-lg">
+      <div class="modal-content">
+        <div class="modal-header">
+          <h5 class="modal-title" id="offline-download-title">
+            <i class="bi bi-cloud-download me-2"></i>Download Offline Map
+          </h5>
+          <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close" id="offline-download-close-btn"></button>
+        </div>
+
+        <!-- Form view (shown until Start is clicked) -->
+        <div class="modal-body" id="offline-download-form-view">
+          <p class="text-muted small mb-3">
+            Pre-fetch map tiles so they're available when you're offline.
+            Only the OpenStreetMap and Topographic base maps can be downloaded;
+            other providers don't permit bulk caching.
+          </p>
+
+          <!-- Base map -->
+          <div class="mb-3">
+            <label for="offline-basemap-select" class="form-label fw-bold">Base map</label>
+            <select class="form-select form-select-sm" id="offline-basemap-select">
+              <option value="topo">Topographic</option>
+              <option value="osm">OpenStreetMap</option>
+            </select>
+          </div>
+
+          <!-- Area -->
+          <div class="mb-3">
+            <label class="form-label fw-bold mb-1">Area to download</label>
+            <div class="form-check">
+              <input class="form-check-input" type="radio" name="offline-area" id="offline-area-view" value="view" checked>
+              <label class="form-check-label" for="offline-area-view">
+                Current map view
+                <span class="text-muted small" id="offline-area-view-info"></span>
+              </label>
+            </div>
+            <div class="form-check">
+              <input class="form-check-input" type="radio" name="offline-area" id="offline-area-district" value="district">
+              <label class="form-check-label" for="offline-area-district">
+                District boundary
+                <span class="text-muted small" id="offline-area-district-info"></span>
+              </label>
+            </div>
+            <div class="form-check">
+              <input class="form-check-input" type="radio" name="offline-area" id="offline-area-ghana" value="ghana">
+              <label class="form-check-label" for="offline-area-ghana">
+                Entire Ghana <span class="text-muted small">(very large — only attempt over fast Wi-Fi)</span>
+              </label>
+            </div>
+          </div>
+
+          <!-- Zoom range -->
+          <div class="mb-3">
+            <label class="form-label fw-bold mb-1">Zoom levels</label>
+            <div class="row g-2 align-items-center">
+              <div class="col-auto"><label for="offline-min-zoom" class="form-label small mb-0">Min</label></div>
+              <div class="col-auto">
+                <input type="number" class="form-control form-control-sm" id="offline-min-zoom" min="6" max="19" value="10" style="width:5em;">
+              </div>
+              <div class="col-auto"><label for="offline-max-zoom" class="form-label small mb-0">Max</label></div>
+              <div class="col-auto">
+                <input type="number" class="form-control form-control-sm" id="offline-max-zoom" min="6" max="19" value="15" style="width:5em;">
+              </div>
+              <div class="col text-muted small">10 = regional · 13 = neighbourhood · 16 = building</div>
+            </div>
+          </div>
+
+          <!-- Estimate -->
+          <div class="alert alert-info py-2 px-3 mb-3" id="offline-estimate" style="font-size:0.9em;">
+            <strong>Estimated download:</strong>
+            <span id="offline-estimate-detail">Calculating…</span>
+          </div>
+
+          <!-- Acknowledgement -->
+          <div class="form-check mb-2">
+            <input class="form-check-input" type="checkbox" id="offline-ack-check">
+            <label class="form-check-label small" for="offline-ack-check">
+              I understand this counts against the tile provider's usage quota
+              and will use mobile data if I'm not on Wi-Fi.
+            </label>
+          </div>
+        </div>
+
+        <!-- Progress view (shown during download) -->
+        <div class="modal-body d-none" id="offline-download-progress-view">
+          <div class="text-center mb-3">
+            <div class="fs-5 fw-bold" id="offline-progress-percent">0%</div>
+            <div class="small text-muted" id="offline-progress-counts">0 of 0 tiles</div>
+          </div>
+          <div class="progress mb-3" style="height:1.25em;">
+            <div class="progress-bar progress-bar-striped progress-bar-animated"
+                 role="progressbar" id="offline-progress-bar"
+                 aria-valuemin="0" aria-valuemax="100" style="width:0%;"></div>
+          </div>
+          <div class="row text-center small text-muted">
+            <div class="col"><div class="fw-bold text-body" id="offline-progress-ok">0</div>fetched</div>
+            <div class="col"><div class="fw-bold text-body" id="offline-progress-failed">0</div>failed</div>
+            <div class="col"><div class="fw-bold text-body" id="offline-progress-eta">—</div>remaining</div>
+          </div>
+        </div>
+
+        <!-- Done view (shown after completion) -->
+        <div class="modal-body d-none" id="offline-download-done-view">
+          <div class="text-center py-3">
+            <i class="bi bi-check-circle-fill text-success" style="font-size:3rem;"></i>
+            <div class="fs-5 fw-bold mt-2" id="offline-done-title">Download complete</div>
+            <div class="text-muted" id="offline-done-detail"></div>
+          </div>
+        </div>
+
+        <div class="modal-footer">
+          <button type="button" class="btn btn-secondary" data-bs-dismiss="modal" id="offline-download-cancel-btn">
+            Cancel
+          </button>
+          <button type="button" class="btn btn-primary" id="offline-download-start-btn" disabled>
+            <i class="bi bi-cloud-download me-1"></i>Start download
+          </button>
+          <button type="button" class="btn btn-primary d-none" id="offline-download-close-done-btn" data-bs-dismiss="modal">
+            Close
+          </button>
+        </div>
+      </div>
+    </div>
+  </div>

  <!-- Polyfill crypto.randomUUID for non-secure contexts (HTTP) -->
  <!-- Must run before module imports (SQLocal/coincident require it) -->
--- a/dist/manifest.json
+++ b/dist/manifest.json
@ -1,58 +1,58 @@
 {
  "name": "LUPMIS2 Drawing Tools",
-  "short_name": "LUPMIS",
+  "short_name": "LUPMIS2",
  "description": "Map and GIS functions for Land Use Planning in Ghana",
-  "start_url": "/",
-  "scope": "/",
+  "start_url": "./",
+  "scope": "./",
  "display": "standalone",
  "background_color": "#ffffff",
  "theme_color": "#005eb8",
  "orientation": "any",
  "icons": [
    {
-      "src": "/icons/icon-72.png",
+      "src": "./icons/luspa-72x72.png",
      "sizes": "72x72",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/icon-96.png",
+      "src": "./icons/luspa-96x96.png",
      "sizes": "96x96",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/icon-128.png",
+      "src": "./icons/luspa-128x128.png",
      "sizes": "128x128",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/icon-144.png",
+      "src": "./icons/luspa-144x144.png",
      "sizes": "144x144",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/icon-152.png",
+      "src": "./icons/luspa-152x152.png",
      "sizes": "152x152",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/luspa-192x192.png",
+      "src": "./icons/luspa-192x192.png",
      "sizes": "192x192",
      "type": "image/png",
      "purpose": "any maskable"
    },
    {
-      "src": "/icons/icon-384.png",
+      "src": "./icons/luspa-384x384.png",
      "sizes": "384x384",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/luspa-512x512.png",
+      "src": "./icons/luspa-512x512.png",
      "sizes": "512x512",
      "type": "image/png",
      "purpose": "any maskable"
--- a/dist/sw.js
+++ b/dist/sw.js
@ -1,29 +1,81 @@
 /**
 * Service Worker
- * 
+ *
 * Handles caching of:
 * - App shell (HTML, CSS, JS)
- * - Map tiles (runtime caching)
+ * - Map tiles (passive runtime caching, per-host buckets)
 * - API responses (network-first)
- * 
+ *
 * Note: Database operations are handled by the SharedWorker (shared-db-worker.js),
 *       NOT by this service worker. They serve different purposes:
 *       - Service Worker: Caching, offline asset serving, push notifications
 *       - SharedWorker: Shared database connection across tabs
 */

-const CACHE_VERSION = 'v1';
-const SHELL_CACHE = `shell-${CACHE_VERSION}`;
-const TILES_CACHE = `tiles-${CACHE_VERSION}`;
+// v3: lower per-cache limits (5000 → 1500) and counter-based eviction to
+//     prevent Safari memory-pressure reloads.
+// v4: raise OSM and Topographic limits to 8000 to support active offline
+//     downloads (Phase 2). Other providers stay at 1500.
+const CACHE_VERSION = 'v4';
+const SHELL_CACHE   = `shell-${CACHE_VERSION}`;
 const MODULES_CACHE = `modules-${CACHE_VERSION}`;
-const API_CACHE = `api-${CACHE_VERSION}`;
+const API_CACHE     = `api-${CACHE_VERSION}`;

-// Maximum number of tiles to cache
-const MAX_TILES = 500;
+// ----------------------------------------------------------------------------
+// Tile caches — one per provider so users can clear them independently.
+// Limits are per-cache (not global). 5 000 tiles ≈ ~150 MB at ~30 KB/tile,
+// which covers a Ghana district at zoom 10–15 (typical field-work range).
+// ----------------------------------------------------------------------------
+const TILES_OSM         = `tiles-osm-${CACHE_VERSION}`;
+const TILES_TOPO        = `tiles-topo-${CACHE_VERSION}`;
+const TILES_SATELLITE   = `tiles-satellite-${CACHE_VERSION}`;
+const TILES_CARTO_LIGHT = `tiles-carto-light-${CACHE_VERSION}`;
+const TILES_CARTO_DARK  = `tiles-carto-dark-${CACHE_VERSION}`;

-// App shell assets - precached on install
-// Vite will generate hashed filenames, so we cache the entry points
-// and let the browser handle the hashed assets
+// Per-provider tile limits.
+//   • OSM and Topographic are the providers offered for active offline
+//     download (Phase 2 dialog), so they get a higher cap (~240 MB each at
+//     ~30 KB/tile) — enough for a typical Ghana district at zoom 10–15.
+//   • The other providers serve passive caching only (whatever the user has
+//     already viewed), so 1 500 tiles ≈ 45 MB is plenty.
+//
+// Total max ≈ 5 × ~150 MB = ~750 MB on disk in the worst case, but only the
+// two downloadable buckets are likely to fill. Eviction sweeps run every 100
+// inserts (see EVICTION_CHECK_INTERVAL) so memory pressure stays bounded.
+const TILE_LIMITS = {
+  [TILES_OSM]:         8000,
+  [TILES_TOPO]:        8000,
+  [TILES_SATELLITE]:   1500,
+  [TILES_CARTO_LIGHT]: 1500,
+  [TILES_CARTO_DARK]:  1500,
+};
+
+// Per-cache running insert counter, in memory. Avoids calling cache.keys()
+// (which materialises every Request object in the cache) on every put — that
+// was the cause of the Safari "reloaded due to memory pressure" failures.
+//
+// We only run a real eviction sweep every EVICTION_CHECK_INTERVAL inserts.
+const _tileInsertCounters = new Map(); // cacheName → number of inserts since last eviction
+const EVICTION_CHECK_INTERVAL = 100;
+
+// Friendly name shown in the UI (matches Settings card labels)
+const TILE_CACHE_LABELS = {
+  [TILES_OSM]:         'OpenStreetMap',
+  [TILES_TOPO]:        'Topographic',
+  [TILES_SATELLITE]:   'Satellite',
+  [TILES_CARTO_LIGHT]: 'Carto Light',
+  [TILES_CARTO_DARK]:  'Carto Dark',
+};
+
+const ALL_TILE_CACHES = Object.keys(TILE_LIMITS);
+
+// Approximate average tile size — used for storage estimation.
+// Real measurements: PNG tiles range 5–80 KB; 30 KB is a good middle ground.
+const AVG_TILE_BYTES = 30 * 1024;
+
+// ----------------------------------------------------------------------------
+// App shell assets — precached on install.
+// ----------------------------------------------------------------------------
 const SHELL_ASSETS = [
  '/',
  '/index.html',
@ -37,7 +89,7 @@ const SHELL_ASSETS = [

 self.addEventListener('install', (event) => {
  console.log('[SW] Installing...');
-  
+
  event.waitUntil(
    caches.open(SHELL_CACHE)
      .then((cache) => {
@ -54,18 +106,26 @@ self.addEventListener('install', (event) => {

 self.addEventListener('activate', (event) => {
  console.log('[SW] Activating...');
-  
+
  event.waitUntil(
    caches.keys()
      .then((cacheNames) => {
+        // Build the set of caches that should remain
+        const keep = new Set([SHELL_CACHE, MODULES_CACHE, API_CACHE, ...ALL_TILE_CACHES]);
+
        return Promise.all(
          cacheNames
+            // Delete anything that:
+            //  • belongs to one of our managed cache prefixes (shell-, tiles-, modules-, api-)
+            //  • but is NOT in the current keep set
+            // This includes the legacy "tiles-v1" single bucket.
            .filter((name) => {
-              // Delete old version caches
-              return (name.startsWith('shell-') && name !== SHELL_CACHE) ||
-                     (name.startsWith('tiles-') && name !== TILES_CACHE) ||
-                     (name.startsWith('modules-') && name !== MODULES_CACHE) ||
-                     (name.startsWith('api-') && name !== API_CACHE);
+              const isOurs =
+                name.startsWith('shell-') ||
+                name.startsWith('tiles-') ||
+                name.startsWith('modules-') ||
+                name.startsWith('api-');
+              return isOurs && !keep.has(name);
            })
            .map((name) => {
              console.log('[SW] Deleting old cache:', name);
@ -84,17 +144,28 @@ self.addEventListener('activate', (event) => {
 self.addEventListener('fetch', (event) => {
  const request = event.request;
  const url = new URL(request.url);
-  
+
  // Only handle GET requests
  if (request.method !== 'GET') return;
-  
+
  // Skip chrome-extension and other non-http(s) requests
  if (!url.protocol.startsWith('http')) return;
-  
-  // Route to appropriate caching strategy
-  if (isMapTile(url)) {
-    event.respondWith(cacheThenNetwork(request, TILES_CACHE, MAX_TILES));
-  } else if (isApiRequest(url)) {
+
+  // Skip worker files and Vite dev-server node_modules requests —
+  // intercepting these breaks module workers (e.g. SQLocal/SQLite).
+  if (url.pathname.includes('node_modules') ||
+      url.search.includes('worker_file') ||
+      request.destination === 'worker') return;
+
+  // ----- TILE REQUESTS — passive cache-then-network (per-host bucket) -----
+  const tileCache = getTileCacheName(url);
+  if (tileCache) {
+    event.respondWith(tileCacheThenNetwork(request, tileCache));
+    return;
+  }
+
+  // ----- OTHER ROUTES (unchanged) -----
+  if (isApiRequest(url)) {
    event.respondWith(networkFirst(request, API_CACHE));
  } else if (isModuleAsset(url)) {
    event.respondWith(staleWhileRevalidate(request, MODULES_CACHE));
@ -108,15 +179,36 @@ self.addEventListener('fetch', (event) => {
 // URL CLASSIFICATION
 // ============================================================================

-function isMapTile(url) {
-  // Common tile server patterns for all our base maps
-  return url.hostname.includes('tile.openstreetmap.org') ||
-         url.hostname.includes('opentopomap.org') ||
-         url.hostname.includes('arcgisonline.com') ||
-         url.hostname.includes('basemaps.cartocdn.com') ||
-         url.hostname.includes('tiles.') ||
-         url.pathname.match(/\/\d+\/\d+\/\d+\.(png|jpg|pbf)$/) ||
-         url.pathname.match(/\/tile\/\d+\/\d+\/\d+/);
+/**
+ * Classify a URL into the appropriate tile cache.
+ * Returns `null` for non-tile requests, or for tile providers we deliberately
+ * do NOT cache (e.g. Google — caching is forbidden by their ToS).
+ */
+function getTileCacheName(url) {
+  const host = url.hostname;
+
+  // OpenStreetMap — tile.openstreetmap.org and a/b/c subdomains
+  if (host.endsWith('tile.openstreetmap.org')) return TILES_OSM;
+
+  // OpenTopoMap — a/b/c.tile.opentopomap.org
+  if (host.endsWith('tile.opentopomap.org') || host.endsWith('opentopomap.org')) return TILES_TOPO;
+
+  // Carto Basemaps — light_all / dark_all distinguished by path
+  if (host.endsWith('basemaps.cartocdn.com')) {
+    if (url.pathname.includes('/light_all/')) return TILES_CARTO_LIGHT;
+    if (url.pathname.includes('/dark_all/'))  return TILES_CARTO_DARK;
+    return null; // unknown Carto style
+  }
+
+  // Esri — server.arcgisonline.com
+  if (host.endsWith('arcgisonline.com')) return TILES_SATELLITE;
+
+  // Google — caching forbidden by ToS, do not store
+  if (host.endsWith('google.com') || host.endsWith('googleapis.com')) return null;
+
+  // Other tile providers (WMS endpoints, OWS, custom) — not cached at this layer
+  // (the user's "online only" toast handles those).
+  return null;
 }

 function isApiRequest(url) {
@ -129,7 +221,6 @@ function isModuleAsset(url) {
 }

 function isAppAsset(url) {
-  // Same origin, common asset extensions
  return url.origin === self.location.origin &&
         (url.pathname.endsWith('.html') ||
          url.pathname.endsWith('.css') ||
@ -144,13 +235,13 @@ function isAppAsset(url) {
 // ============================================================================

 /**
- * Cache First - Use cache, fallback to network
- * Best for: App shell, static assets
+ * Cache First — Use cache, fallback to network.
+ * Best for: App shell, static assets.
 */
 async function cacheFirst(request, cacheName) {
  const cached = await caches.match(request);
  if (cached) return cached;
-  
+
  try {
    const response = await fetch(request);
    if (response.ok) {
@ -159,7 +250,6 @@ async function cacheFirst(request, cacheName) {
    }
    return response;
  } catch (error) {
-    // Return offline page for navigation requests
    if (request.mode === 'navigate') {
      return caches.match('/offline.html');
    }
@ -168,8 +258,8 @@ async function cacheFirst(request, cacheName) {
 }

 /**
- * Network First - Try network, fallback to cache
- * Best for: API requests, dynamic content
+ * Network First — Try network, fallback to cache.
+ * Best for: API requests, dynamic content.
 */
 async function networkFirst(request, cacheName) {
  try {
@ -187,89 +277,141 @@ async function networkFirst(request, cacheName) {
 }

 /**
- * Stale While Revalidate - Return cache immediately, update in background
- * Best for: Module assets, frequently updated content
+ * Stale While Revalidate — Return cache immediately, update in background.
+ * Best for: Module assets, frequently updated content.
 */
 async function staleWhileRevalidate(request, cacheName) {
  const cache = await caches.open(cacheName);
  const cached = await cache.match(request);
-  
+
  const fetchPromise = fetch(request).then((response) => {
    if (response.ok) {
      cache.put(request, response.clone());
    }
    return response;
  }).catch(() => cached);
-  
+
  return cached || fetchPromise;
 }

 /**
- * Cache Then Network with limit - Cache tiles with size limit
- * Best for: Map tiles
+ * Tile Cache then Network — Per-host bucket with size limit.
+ * Cache first; on miss, fetch from network and store.
+ *
+ * Memory-conservative eviction:
+ *   • Increments an in-memory counter on every successful insert
+ *   • Only calls cache.keys() (which materialises all Request objects) every
+ *     EVICTION_CHECK_INTERVAL inserts — so the cost is amortised
+ *   • Eviction drops the oldest 10 % when over the per-host limit
+ *
+ * On network failure (offline), serves a 408 so the map renders a blank tile
+ * rather than throwing.
 */
-async function cacheThenNetwork(request, cacheName, maxItems) {
+async function tileCacheThenNetwork(request, cacheName) {
  const cache = await caches.open(cacheName);
  const cached = await cache.match(request);
-  
  if (cached) return cached;
-  
+
  try {
    const response = await fetch(request);
-    
+
    if (response.ok) {
-      // Check cache size and trim if needed
-      const keys = await cache.keys();
-      if (keys.length >= maxItems) {
-        // Remove oldest entries (first 10%)
-        const toDelete = keys.slice(0, Math.ceil(maxItems * 0.1));
-        await Promise.all(toDelete.map(key => cache.delete(key)));
+      // Bump the counter; periodically run a real eviction sweep
+      const count = (_tileInsertCounters.get(cacheName) || 0) + 1;
+      _tileInsertCounters.set(cacheName, count);
+
+      if (count % EVICTION_CHECK_INTERVAL === 0) {
+        // Reset the counter — next sweep is another EVICTION_CHECK_INTERVAL away
+        _tileInsertCounters.set(cacheName, 0);
+        await maybeEvict(cache, cacheName);
      }
-      
-      cache.put(request, response.clone());
+
+      // Don't await put() — it can run after we return the response, keeping
+      // the fetch hot path lightweight.
+      cache.put(request, response.clone()).catch((err) => {
+        // QuotaExceededError → run an immediate eviction sweep and retry once
+        if (err && err.name === 'QuotaExceededError') {
+          maybeEvict(cache, cacheName, /* force */ true).catch(() => {});
+        }
+      });
    }
-    
+
    return response;
  } catch (error) {
-    // For tiles, just fail silently - map will show blank tile
+    // Offline — let the map renderer show a blank tile
    return new Response('', { status: 408, statusText: 'Offline' });
  }
 }

+/**
+ * Run an eviction sweep on a cache, dropping the oldest 10 % of entries
+ * when over the per-cache limit. Heavy: only call periodically.
+ */
+async function maybeEvict(cache, cacheName, force = false) {
+  try {
+    const limit = TILE_LIMITS[cacheName] || 1500;
+    const keys = await cache.keys();
+    if (force || keys.length >= limit) {
+      const drop = Math.max(1, Math.ceil(limit * 0.1));
+      const toDelete = keys.slice(0, drop);
+      await Promise.all(toDelete.map((k) => cache.delete(k)));
+    }
+  } catch (err) {
+    console.warn('[SW] eviction sweep failed for', cacheName, err);
+  }
+}
+
 // ============================================================================
 // MESSAGE HANDLING
 // ============================================================================

 self.addEventListener('message', (event) => {
  const { type, payload } = event.data || {};
-  
+
  switch (type) {
    case 'SKIP_WAITING':
      self.skipWaiting();
      break;
-      
+
    case 'CACHE_MODULES':
      cacheModules(payload.modules);
      break;
-      
+
    case 'CLEAR_USER_CACHE':
      clearUserCaches();
      break;
-      
+
    case 'GET_CACHE_STATUS':
-      getCacheStatus().then(status => {
+      getCacheStatus().then((status) => {
        event.source.postMessage({ type: 'CACHE_STATUS', status });
      });
      break;
+
+    // ----- Tile-cache management (Phase 1 offline maps) -----
+    case 'GET_TILE_STATS':
+      getTileStats().then((stats) => {
+        event.source.postMessage({ type: 'TILE_STATS', stats });
+      });
+      break;
+
+    case 'CLEAR_TILE_CACHES':
+      clearTileCaches().then(() => {
+        event.source.postMessage({ type: 'TILE_CACHES_CLEARED' });
+      });
+      break;
  }
 });

+// ============================================================================
+// HELPER FUNCTIONS
+// ============================================================================
+
 /**
- * Cache specific modules on demand
+ * Cache specific modules on demand.
 */
 async function cacheModules(moduleNames) {
  const cache = await caches.open(MODULES_CACHE);
-  
+
  for (const moduleName of moduleNames) {
    try {
      const moduleAssets = [
@ -277,9 +419,8 @@ async function cacheModules(moduleNames) {
        `/modules/${moduleName}/index.css`,
        `/modules/${moduleName}/index.html`
      ];
-      
+
      await cache.addAll(moduleAssets.filter(async (url) => {
-        // Only cache assets that exist
        try {
          const response = await fetch(url, { method: 'HEAD' });
          return response.ok;
@ -287,7 +428,7 @@ async function cacheModules(moduleNames) {
          return false;
        }
      }));
-      
+
      console.log('[SW] Cached module:', moduleName);
    } catch (error) {
      console.warn('[SW] Failed to cache module:', moduleName, error);
@ -296,7 +437,8 @@ async function cacheModules(moduleNames) {
 }

 /**
- * Clear user-specific caches (call on logout)
+ * Clear user-specific caches (call on logout).
+ * Tile caches are NOT cleared here — those belong to the device, not the user.
 */
 async function clearUserCaches() {
  await caches.delete(API_CACHE);
@ -305,17 +447,90 @@ async function clearUserCaches() {
 }

 /**
- * Get cache status information
+ * Get summary status of all caches (count of entries in each).
 */
 async function getCacheStatus() {
  const cacheNames = await caches.keys();
  const status = {};
-  
+
  for (const name of cacheNames) {
    const cache = await caches.open(name);
    const keys = await cache.keys();
    status[name] = keys.length;
  }
-  
+
  return status;
 }
+
+/**
+ * Get per-provider tile cache statistics.
+ *
+ * Returns shape:
+ *   {
+ *     totals: { count, estBytes },
+ *     byProvider: [{ key, label, count, limit, estBytes }, ...]
+ *   }
+ *
+ * estBytes is an approximation (count × AVG_TILE_BYTES). For an exact size,
+ * the caller can use navigator.storage.estimate() on the page side.
+ *
+ * Result is cached for STATS_TTL_MS so rapid re-queries (e.g. multiple
+ * Settings opens) don't re-enumerate every cache.
+ */
+const STATS_TTL_MS = 10 * 1000;
+let _cachedStats = null;
+let _cachedStatsAt = 0;
+
+async function getTileStats({ force = false } = {}) {
+  const now = Date.now();
+  if (!force && _cachedStats && (now - _cachedStatsAt) < STATS_TTL_MS) {
+    return _cachedStats;
+  }
+
+  const byProvider = [];
+  let totalCount = 0;
+
+  for (const cacheName of ALL_TILE_CACHES) {
+    let count = 0;
+    if (await caches.has(cacheName)) {
+      const cache = await caches.open(cacheName);
+      // matchAll returns a smaller payload than keys() on Safari, but neither
+      // is free. Done at most once per STATS_TTL_MS thanks to the cache above.
+      const keys = await cache.keys();
+      count = keys.length;
+    }
+    byProvider.push({
+      key:      cacheName,
+      label:    TILE_CACHE_LABELS[cacheName] || cacheName,
+      count,
+      limit:    TILE_LIMITS[cacheName] || 0,
+      estBytes: count * AVG_TILE_BYTES,
+    });
+    totalCount += count;
+  }
+
+  _cachedStats = {
+    totals: {
+      count:    totalCount,
+      estBytes: totalCount * AVG_TILE_BYTES,
+    },
+    byProvider,
+  };
+  _cachedStatsAt = now;
+  return _cachedStats;
+}
+
+/**
+ * Delete every tile cache. Frees the device storage used by cached map tiles.
+ * Does not affect app-shell, modules, or API caches.
+ */
+async function clearTileCaches() {
+  const results = await Promise.all(
+    ALL_TILE_CACHES.map((name) => caches.delete(name))
+  );
+  // Reset counters and invalidate stats cache
+  _tileInsertCounters.clear();
+  _cachedStats = null;
+  _cachedStatsAt = 0;
+  console.log('[SW] Cleared tile caches:', ALL_TILE_CACHES.filter((_, i) => results[i]));
+}
--- a/dist/icons/luspa.icon/Assets/luspalogo.png
+++ b/dist/icons/luspa.icon/Assets/luspalogo.png
--- a/dist/icons/luspa.icon/icon.json
+++ b/dist/icons/luspa.icon/icon.json
--- a/index.html
+++ b/index.html
@ -2,19 +2,64 @@
 <html lang="en" data-bs-theme="light">
 <head>
  <meta charset="UTF-8">
-  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0, viewport-fit=cover">
  <meta name="theme-color" content="#005eb8">
  <meta name="description" content="LUPMIS2 Drawing Tools">

  <!-- PWA Manifest -->
-  <link rel="manifest" href="/manifest.json">
-  <link rel="apple-touch-icon" href="/icons/luspa.icon">
-  <link rel="icon" href="/icons/luspa.icon">
+  <link rel="manifest" href="manifest.json">
+  <link rel="apple-touch-icon" sizes="192x192" href="icons/luspa-192x192.png">
+  <link rel="icon" type="image/png" sizes="32x32" href="icons/luspa-32x32.png">
+  <link rel="icon" type="image/png" sizes="16x16" href="icons/luspa-16x16.png">

-  <!-- LUSPA Design System Fonts: Bebas Neue (display) + Exo (body) -->
-  <link rel="preconnect" href="https://fonts.googleapis.com">
-  <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
-  <link href="https://fonts.googleapis.com/css2?family=Bebas+Neue&family=Exo:wght@300;400;500;600;700;800&display=swap" rel="stylesheet">
+  <!-- LUSPA Design System Fonts: Bebas Neue (display) + Exo (body) — self-hosted -->
+  <style>
+    /* Bebas Neue 400 — latin-ext */
+    @font-face {
+      font-family: 'Bebas Neue';
+      font-style: normal;
+      font-weight: 400;
+      font-display: swap;
+      src: url('/fonts/bebas-neue-latin-ext.woff2') format('woff2');
+      unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
+    }
+    /* Bebas Neue 400 — latin */
+    @font-face {
+      font-family: 'Bebas Neue';
+      font-style: normal;
+      font-weight: 400;
+      font-display: swap;
+      src: url('/fonts/bebas-neue-latin.woff2') format('woff2');
+      unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
+    }
+    /* Exo 300-800 — vietnamese */
+    @font-face {
+      font-family: 'Exo';
+      font-style: normal;
+      font-weight: 300 800;
+      font-display: swap;
+      src: url('/fonts/exo-vietnamese.woff2') format('woff2');
+      unicode-range: U+0102-0103, U+0110-0111, U+0128-0129, U+0168-0169, U+01A0-01A1, U+01AF-01B0, U+0300-0301, U+0303-0304, U+0308-0309, U+0323, U+0329, U+1EA0-1EF9, U+20AB;
+    }
+    /* Exo 300-800 — latin-ext */
+    @font-face {
+      font-family: 'Exo';
+      font-style: normal;
+      font-weight: 300 800;
+      font-display: swap;
+      src: url('/fonts/exo-latin-ext.woff2') format('woff2');
+      unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
+    }
+    /* Exo 300-800 — latin */
+    @font-face {
+      font-family: 'Exo';
+      font-style: normal;
+      font-weight: 300 800;
+      font-display: swap;
+      src: url('/fonts/exo-latin.woff2') format('woff2');
+      unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
+    }
+  </style>

  <title>LUPMIS2 Drawing Tools</title>

@ -106,6 +151,295 @@
      --radius-2xl: 1rem;
    }

+    /* ─── Fieldwork Mode ─── high-contrast + larger touch targets ─── */
+    .fieldwork-mode {
+      --foreground: #000;
+      --background: #fff;
+      --card: #fff;
+      --card-foreground: #000;
+      --primary: #0044aa;
+      --primary-foreground: #fff;
+      --primary-hover: #003080;
+      --muted: #e0e0e0;
+      --muted-foreground: #333;
+      --accent: #cce0ff;
+      --accent-foreground: #000;
+      --border: rgba(0,0,0,0.25);
+      --success: #005a00;
+      --success-foreground: #fff;
+      --warning: #b36b00;
+      --warning-foreground: #000;
+      --destructive: #b80000;
+      --destructive-foreground: #fff;
+      --ring: #0044aa;
+      --bs-body-color: #000;
+    }
+
+    /* Fieldwork: larger dock buttons */
+    .fieldwork-mode .dock-btn {
+      min-width: 72px;
+      min-height: 58px;
+      font-size: 1.6rem;
+      border-width: 2px;
+    }
+    .fieldwork-mode .dock-btn-label {
+      font-size: 0.75rem;
+      font-weight: 600;
+    }
+
+    /* Fieldwork: bolder navbar */
+    .fieldwork-mode .navbar {
+      border-bottom-width: 4px;
+    }
+    .fieldwork-mode .navbar .navbar-brand {
+      font-size: 1.6rem;
+    }
+
+    /* Fieldwork: larger offcanvas toggle buttons */
+    .fieldwork-mode .offcanvas-toggle {
+      width: 44px;
+      height: 44px;
+      font-size: 1.2rem;
+    }
+
+    /* Fieldwork: thicker bottom dock border */
+    .fieldwork-mode .bottom-dock {
+      border-top-width: 4px;
+    }
+
+    /* Fieldwork: larger text in cards / lists */
+    .fieldwork-mode .card-header h6 {
+      font-size: 1rem;
+    }
+    .fieldwork-mode .list-group-item {
+      font-size: 0.95rem;
+      padding: 0.65rem 1rem;
+    }
+
+    /* Fieldwork: larger buttons globally */
+    .fieldwork-mode .btn {
+      font-size: 0.95rem;
+      padding: 0.5rem 1rem;
+      font-weight: 600;
+    }
+    .fieldwork-mode .btn-sm {
+      font-size: 0.85rem;
+      padding: 0.4rem 0.75rem;
+    }
+
+    /* Fieldwork: stronger borders on inputs / form controls */
+    .fieldwork-mode .form-control,
+    .fieldwork-mode .form-select {
+      border-width: 2px;
+      border-color: #555;
+      font-size: 1rem;
+    }
+
+    /* Fieldwork: bolder map controls (ol-ext) */
+    .fieldwork-mode .ol-control button {
+      font-size: 1.3rem;
+      width: 2.2em;
+      height: 2.2em;
+    }
+
+    /* Fieldwork: scale bar text legibility */
+    .fieldwork-mode .ol-scale-bar .ol-scale-step-text,
+    .fieldwork-mode .ol-scale-bar .ol-scale-text {
+      font-size: 12px;
+      font-weight: 700;
+      text-shadow: 0 0 4px #fff, 0 0 8px #fff;
+    }
+
+    /* ─── Dark Mode ─── reversed colour scheme ─── */
+    .dark-mode {
+      --foreground: #e0dff0;
+      --background: #131325;
+      --card: #1e1e38;
+      --card-foreground: #e0dff0;
+      --primary: #4d9de6;
+      --primary-foreground: #fff;
+      --primary-hover: #6fb3f0;
+      --muted: #272745;
+      --muted-foreground: #9594a8;
+      --accent: #1e3a5f;
+      --accent-foreground: #e0dff0;
+      --border: rgba(255,255,255,0.12);
+      --ring: #4d9de6;
+      --success: #2dd46a;
+      --success-foreground: #131325;
+      --warning: #ffb84d;
+      --warning-foreground: #131325;
+      --destructive: #f04040;
+      --destructive-foreground: #fff;
+      --bs-body-color: #e0dff0;
+      --bs-body-bg: #131325;
+      --bs-tertiary-bg: #1e1e38;
+      color-scheme: dark;
+    }
+
+    /* Dark: navbar */
+    .dark-mode .navbar {
+      background-color: #1a1a30 !important;
+      box-shadow: 0 1px 6px rgba(0,0,0,0.4);
+    }
+
+    /* Dark: bottom dock */
+    .dark-mode .bottom-dock {
+      background-color: #1a1a30;
+      box-shadow: 0 -2px 10px rgba(0,0,0,0.3);
+    }
+    .dark-mode .dock-btn {
+      border-color: var(--primary);
+      color: var(--foreground);
+    }
+    .dark-mode .dock-btn:hover {
+      background-color: var(--muted);
+    }
+    .dark-mode .dock-btn.active {
+      background-color: var(--primary);
+      color: var(--primary-foreground);
+    }
+
+    /* Dark: offcanvas panels */
+    .dark-mode .offcanvas {
+      background-color: var(--background) !important;
+      color: var(--foreground) !important;
+    }
+    .dark-mode .offcanvas-header {
+      border-bottom-color: var(--border) !important;
+    }
+    .dark-mode .btn-close {
+      filter: invert(1) grayscale(100%) brightness(200%);
+    }
+
+    /* Dark: cards */
+    .dark-mode .card {
+      background-color: var(--card) !important;
+      color: var(--card-foreground) !important;
+      border-color: var(--border) !important;
+    }
+
+    /* Dark: offcanvas toggle buttons */
+    .dark-mode .offcanvas-toggle {
+      background-color: var(--card);
+      color: var(--foreground);
+      border-color: var(--border);
+    }
+    .dark-mode .offcanvas-toggle:hover {
+      background-color: var(--primary);
+      color: var(--primary-foreground);
+    }
+
+    /* Dark: form controls */
+    .dark-mode .form-control,
+    .dark-mode .form-select {
+      background-color: var(--muted) !important;
+      color: var(--foreground) !important;
+      border-color: var(--border) !important;
+    }
+    .dark-mode .form-check-input {
+      background-color: var(--muted);
+      border-color: var(--muted-foreground);
+    }
+    .dark-mode .form-check-input:checked {
+      background-color: var(--primary);
+      border-color: var(--primary);
+    }
+
+    /* Dark: list groups */
+    .dark-mode .list-group-item {
+      background-color: var(--card) !important;
+      color: var(--card-foreground) !important;
+      border-color: var(--border) !important;
+    }
+
+    /* Dark: buttons */
+    .dark-mode .btn-outline-primary {
+      color: var(--primary);
+      border-color: var(--primary);
+    }
+    .dark-mode .btn-outline-danger {
+      color: var(--destructive);
+      border-color: var(--destructive);
+    }
+
+    /* Dark: text utilities */
+    .dark-mode .text-muted {
+      color: var(--muted-foreground) !important;
+    }
+
+    /* Dark: measurement tooltips */
+    .dark-mode .measure-tooltip {
+      background: rgba(30, 30, 56, 0.95);
+      color: var(--foreground);
+      border-color: var(--primary);
+    }
+    .dark-mode .measure-tooltip::before {
+      border-right-color: var(--primary);
+    }
+
+    /* Dark: OL controls */
+    .dark-mode .ol-control button {
+      background-color: var(--card) !important;
+      color: var(--foreground) !important;
+    }
+    .dark-mode .ol-control button:hover {
+      background-color: var(--primary) !important;
+      color: var(--primary-foreground) !important;
+    }
+    .dark-mode .ol-attribution,
+    .dark-mode .ol-attribution a {
+      color: var(--muted-foreground) !important;
+    }
+
+    /* Dark: scale bar */
+    .dark-mode .ol-scale-bar .ol-scale-step-text,
+    .dark-mode .ol-scale-bar .ol-scale-text {
+      color: #fff !important;
+      text-shadow: 0 0 4px #000, 0 0 8px #000 !important;
+    }
+    .dark-mode .ol-scale-bar .ol-scale-singlebar-even {
+      background-color: #fff !important;
+    }
+    .dark-mode .ol-scale-bar .ol-scale-singlebar-odd {
+      background-color: #999 !important;
+    }
+
+    /* Dark: map drop overlay */
+    .dark-mode .map-drop-overlay {
+      background: rgba(19, 19, 37, 0.85);
+      border-color: var(--primary);
+      color: var(--foreground);
+    }
+
+    /* Dark: ol-ext LayerSwitcher */
+    .dark-mode .ol-layerswitcher {
+      background-color: var(--card) !important;
+    }
+    .dark-mode .ol-layerswitcher .panel {
+      background-color: var(--card) !important;
+      color: var(--foreground) !important;
+    }
+    .dark-mode .ol-layerswitcher .panel li {
+      color: var(--foreground);
+    }
+    .dark-mode .ol-layerswitcher .ol-switchertopdiv,
+    .dark-mode .ol-layerswitcher .ol-switcherbottomdiv {
+      background: var(--card) !important;
+    }
+
+    /* Dark: alert boxes */
+    .dark-mode .alert-danger {
+      background-color: rgba(240, 64, 64, 0.15) !important;
+      color: var(--destructive) !important;
+      border-color: var(--destructive) !important;
+    }
+    .dark-mode .alert-success {
+      background-color: rgba(45, 212, 106, 0.15) !important;
+      color: var(--success) !important;
+      border-color: var(--success) !important;
+    }
+
    /* Full height layout */
    html, body {
      height: 100%;
@ -214,9 +548,12 @@
      font-family: var(--font-body);
    }

-    /* Main container - full height */
+    /* Main container - full height.
+       100dvh accounts for mobile browser chrome and OS nav bars.
+       Falls back to 100vh for older browsers. */
    .app-container {
      height: 100vh;
+      height: 100dvh;
      display: flex;
      flex-direction: column;
    }
@ -244,6 +581,35 @@
      height: 100%;
    }

+    /* Drag-and-drop overlay shown when files are dragged over the map */
+    .map-drop-overlay {
+      position: absolute;
+      inset: 0;
+      z-index: 9999;
+      display: flex;
+      align-items: center;
+      justify-content: center;
+      background: rgba(0, 94, 184, 0.15);
+      border: 3px dashed var(--primary, #005eb8);
+      border-radius: 8px;
+      pointer-events: none;
+      opacity: 0;
+      transition: opacity 0.15s ease;
+    }
+    .map-container.drag-over .map-drop-overlay {
+      opacity: 1;
+    }
+    .map-drop-overlay span {
+      font-family: var(--font-body, 'Exo', sans-serif);
+      font-size: 1.15rem;
+      font-weight: 600;
+      color: var(--primary, #005eb8);
+      background: var(--card, #fff);
+      padding: 0.6rem 1.4rem;
+      border-radius: 6px;
+      box-shadow: 0 2px 8px rgba(0,0,0,0.12);
+    }
+
    /* Offline indicator */
    #offline-indicator {
      display: none;
@ -301,9 +667,14 @@
      z-index: 1050;
    }

-    /* Fix ol-ext LayerSwitcher z-index */
-    .ol-layerswitcher {
-      z-index: 100;
+    /* OL controls stacking context fix — OpenLayers sets z-index:0 on
+       .ol-overlaycontainer-stopevent, trapping all controls below the
+       offcanvas-toggle buttons (z-index:500).  Raising the container
+       to 501 lets the LayerSwitcher dropdown render above the toggles.
+       pointer-events:none on the container still lets clicks through
+       to the toggle buttons underneath. */
+    .ol-overlaycontainer-stopevent {
+      z-index: 501 !important;
    }

    /* Alert hint box */
@ -419,7 +790,7 @@
    }

    .offcanvas-toggle-bottom {
-      bottom: 80px; /* Above the dock */
+      bottom: calc(80px + env(safe-area-inset-bottom, 0px)); /* Above the dock */
      left: 50%;
      transform: translateX(-50%);
    }
@ -432,7 +803,10 @@
      transform: translateX(-50%) scale(0.95);
    }

-    /* Bottom Dock — white card style with blue-strong accent */
+    /* Bottom Dock — white card style with blue-strong accent.
+       env(safe-area-inset-bottom) adds padding on devices with a
+       home indicator / gesture bar (e.g. iPhone notch models).
+       The value is 0 on devices without an inset. */
    .bottom-dock {
      position: absolute;
      bottom: 0;
@ -441,7 +815,7 @@
      z-index: 600;
      background-color: var(--card);
      border-top: 3px solid var(--primary);
-      padding: 8px 16px;
+      padding: 8px 16px calc(8px + env(safe-area-inset-bottom, 0px));
      display: flex;
      justify-content: space-around;
      align-items: center;
@ -503,6 +877,13 @@
      justify-content: center;
    }

+    /* Snap-guides toggle — highlighted when active */
+    .ol-snap-toggle.ol-active button {
+      background: var(--primary) !important;
+      color: var(--primary-foreground, #fff) !important;
+      border-radius: 3px;
+    }
+
    /* Touch-friendly improvements for forms and buttons */
    .form-control, .form-select {
      min-height: 44px;
@ -541,6 +922,18 @@
      color: var(--foreground);
    }

+    /* Message log in the right panel */
+    .message-log {
+      max-height: 260px;
+      overflow-y: auto;
+    }
+
+    .message-log-entry {
+      font-size: 0.82rem;
+      border-color: var(--border, #eee) !important;
+      background: transparent;
+    }
+
    /* ol-ext GeolocationButton styling */
    .ol-geobt {
      top: auto !important;
@ -830,6 +1223,7 @@
    /* Locations list in offcanvas - can be taller now without form */
    .offcanvas-end .locations-list {
      max-height: calc(100vh - 280px);
+      max-height: calc(100dvh - 280px);
      overflow-y: auto;
    }

@ -921,17 +1315,32 @@
      font-size: 18px;
    }

-    /* ScaleLine - position above the bottom dock */
-    .ol-scale-line {
-      bottom: 76px !important;
+    /* ScaleBar - position above the bottom dock with 4px gap */
+    .ol-scale-bar {
+      bottom: calc(85px + env(safe-area-inset-bottom, 0px)) !important;
      left: 10px !important;
    }

-    .ol-scale-line-inner {
-      border-color: var(--foreground) !important;
+    .ol-scale-bar .ol-scale-step-text {
      color: var(--foreground) !important;
      font-family: var(--font-body) !important;
      font-size: 11px !important;
+      text-shadow: 0 0 3px var(--background), 0 0 6px var(--background) !important;
+    }
+
+    .ol-scale-bar .ol-scale-text {
+      color: var(--foreground) !important;
+      font-family: var(--font-body) !important;
+      font-size: 11px !important;
+      text-shadow: 0 0 3px var(--background), 0 0 6px var(--background) !important;
+    }
+
+    .ol-scale-bar .ol-scale-singlebar-even {
+      background-color: var(--foreground) !important;
+    }
+
+    .ol-scale-bar .ol-scale-singlebar-odd {
+      background-color: var(--muted-foreground) !important;
    }

    /* ol-ext Bar overrides */
@ -980,6 +1389,7 @@
          </span>
        </div>
        <div id="map"></div>
+        <div class="map-drop-overlay"><span><i class="bi bi-file-earmark-arrow-up me-2"></i>Drop file to import (.shp .geojson .kml)</span></div>

        <!-- Offcanvas toggle buttons -->
        <button class="offcanvas-toggle offcanvas-toggle-left"
@ -1104,17 +1514,40 @@
      <button type="button" class="btn btn-outline-primary w-100 mb-3" id="local-data-btn">
        <i class="bi bi-database me-2"></i>Local Data
      </button>
+      <button type="button" class="btn btn-outline-primary w-100 mb-3" id="import-shp-btn">
+        <i class="bi bi-file-earmark-arrow-up me-2"></i>Import .shp
+      </button>
+      <input type="file" id="shp-file-input" accept=".zip,.shp,.dbf,.shx,.prj" multiple class="d-none">
+      <button type="button" class="btn btn-outline-primary w-100 mb-3" id="import-geojson-btn">
+        <i class="bi bi-file-earmark-arrow-up me-2"></i>Import GeoJSON
+      </button>
+      <input type="file" id="geojson-file-input" accept=".geojson,.json" class="d-none">
+      <button type="button" class="btn btn-outline-primary w-100 mb-3" id="import-kml-btn">
+        <i class="bi bi-file-earmark-arrow-up me-2"></i>Import KML
+      </button>
+      <input type="file" id="kml-file-input" accept=".kml,.kmz" class="d-none">
+      <div id="file-import-alert" class="alert alert-danger alert-dismissible fade show d-none mb-3" role="alert">
+        <small class="message-text"></small>
+        <button type="button" class="btn-close btn-close-sm" data-bs-dismiss="alert" aria-label="Close"></button>
+      </div>
+      <div id="imported-layers-info" class="d-none mb-3"></div>
      <div id="local-data-stats" class="d-none">
        <div class="card">
-          <div class="card-header bg-primary py-2">
+          <div class="card-header bg-primary py-2 d-flex justify-content-between align-items-center">
            <h6 class="mb-0"><i class="bi bi-database me-2"></i>Local Database Tables</h6>
+            <button type="button" class="btn btn-sm btn-outline-light"
+                    id="clear-all-cached-btn"
+                    title="Delete all cached map layers. They will be re-downloaded on next app start.">
+              <i class="bi bi-arrow-clockwise me-1"></i>Refresh cached layers
+            </button>
          </div>
          <div class="card-body p-0">
            <table class="table table-sm table-striped mb-0">
              <thead>
                <tr>
                  <th class="ps-3">Table</th>
-                  <th class="text-end pe-3">Records</th>
+                  <th class="text-end">Records</th>
+                  <th class="text-end pe-3" style="width:3rem;"></th>
                </tr>
              </thead>
              <tbody id="local-data-tbody">
@ -1142,6 +1575,10 @@
            <span class="message-text"></span>
            <button type="button" class="btn-close" data-bs-dismiss="alert" aria-label="Close"></button>
          </div>
+          <div id="warning-message" class="alert alert-warning alert-dismissible fade show d-none" role="alert">
+            <span class="message-text"></span>
+            <button type="button" class="btn-close" data-bs-dismiss="alert" aria-label="Close"></button>
+          </div>

      <!-- Tip -->
          <div class="alert alert-light border-start border-4 border-primary py-2 mb-3" role="alert">
@ -1181,20 +1618,268 @@
              </div>
            </div>
          </div>
+
+          <!-- Message Log -->
+          <div class="card mt-3" id="message-log-card">
+            <div class="card-header bg-transparent py-2 d-flex justify-content-between align-items-center">
+              <h6 class="mb-0" style="font-family:var(--font-body);font-weight:700;"><i class="bi bi-journal-text me-1"></i> Messages</h6>
+              <button class="btn btn-sm btn-link text-muted p-0" id="clear-message-log" title="Clear messages">
+                <i class="bi bi-trash3"></i>
+              </button>
+            </div>
+            <div class="card-body p-0">
+              <div id="message-log" class="message-log list-group list-group-flush">
+                <div class="text-center text-muted py-3">
+                  <small>No messages yet.</small>
+                </div>
+              </div>
+            </div>
+          </div>
+
        </div>
    </div>

  <!-- Bottom Offcanvas -->
  <div class="offcanvas offcanvas-bottom" tabindex="-1" id="offcanvasBottom" aria-labelledby="offcanvasBottomLabel">
    <div class="offcanvas-header">
-      <h5 class="offcanvas-title" id="offcanvasBottomLabel"><i class="bi bi-chevron-down me-2"></i>Bottom Panel</h5>
+      <h5 class="offcanvas-title" id="offcanvasBottomLabel"><i class="bi bi-gear me-2"></i>Settings</h5>
      <button type="button" class="btn-close" data-bs-dismiss="offcanvas" aria-label="Close"></button>
-        </div>
+    </div>
    <div class="offcanvas-body">
-      <p>This is the bottom offcanvas panel.</p>
-      <p>You can add a data table, charts, or other wide content here.</p>
+      <div class="row g-3">
+        <!-- Fieldwork Mode -->
+        <div class="col-12 col-md-6 col-lg-4">
+          <div class="card">
+            <div class="card-body">
+              <div class="d-flex align-items-center justify-content-between">
+                <div>
+                  <h6 class="mb-1" style="font-family:var(--font-body);font-weight:700;">Fieldwork Mode</h6>
+                  <small class="text-muted">High-contrast colours and larger touch targets for bright sunlight and field conditions.</small>
+                </div>
+                <div class="form-check form-switch ms-3">
+                  <input class="form-check-input" type="checkbox" role="switch" id="fieldwork-mode-toggle" style="width:3rem;height:1.5rem;cursor:pointer;">
+                </div>
              </div>
            </div>
+          </div>
+        </div>
+        <!-- Dark Mode -->
+        <div class="col-12 col-md-6 col-lg-4">
+          <div class="card">
+            <div class="card-body">
+              <div class="d-flex align-items-center justify-content-between">
+                <div>
+                  <h6 class="mb-1" style="font-family:var(--font-body);font-weight:700;">Dark Mode</h6>
+                  <small class="text-muted">Reduce glare and save battery with a dark colour scheme.</small>
+                </div>
+                <div class="form-check form-switch ms-3">
+                  <input class="form-check-input" type="checkbox" role="switch" id="dark-mode-toggle" style="width:3rem;height:1.5rem;cursor:pointer;">
+                </div>
+              </div>
+            </div>
+          </div>
+        </div>
+        <!-- Measurement System -->
+        <div class="col-12 col-md-6 col-lg-4">
+          <div class="card">
+            <div class="card-body">
+              <div class="d-flex align-items-center justify-content-between">
+                <div>
+                  <h6 class="mb-1" style="font-family:var(--font-body);font-weight:700;">Measurement System</h6>
+                  <small class="text-muted">Switch between Metric (m, km) and Imperial (ft, mi, acres) units.</small>
+                </div>
+                <div class="form-check form-switch ms-3">
+                  <input class="form-check-input" type="checkbox" role="switch" id="measurement-system-toggle" style="width:3rem;height:1.5rem;cursor:pointer;">
+                  <label class="form-check-label ms-1" id="measurement-system-label" for="measurement-system-toggle" style="font-size:0.8rem;font-weight:600;min-width:55px;">Metric</label>
+                </div>
+              </div>
+            </div>
+          </div>
+        </div>
+        <!-- Default Base Map -->
+        <div class="col-12 col-md-6 col-lg-4">
+          <div class="card">
+            <div class="card-body">
+              <div class="d-flex align-items-center justify-content-between">
+                <div style="flex:1;min-width:0;">
+                  <h6 class="mb-1" style="font-family:var(--font-body);font-weight:700;">Default Base Map</h6>
+                  <small class="text-muted">Base map shown on app start. Saved on this device.</small>
+                </div>
+                <div class="ms-3" style="min-width:140px;">
+                  <select class="form-select form-select-sm" id="default-basemap-select" aria-label="Default base map">
+                    <option value="topo">Topographic</option>
+                    <option value="osm">OpenStreetMap</option>
+                    <option value="satellite">Satellite</option>
+                    <option value="googlesat">Google Sat</option>
+                    <option value="carto-light">Carto Light</option>
+                    <option value="carto-dark">Carto Dark</option>
+                  </select>
+                </div>
+              </div>
+            </div>
+          </div>
+        </div>
+        <!-- Offline Map Tiles -->
+        <div class="col-12 col-md-6 col-lg-8">
+          <div class="card">
+            <div class="card-body">
+              <div class="d-flex align-items-start justify-content-between mb-2">
+                <div style="flex:1;min-width:0;">
+                  <h6 class="mb-1" style="font-family:var(--font-body);font-weight:700;">
+                    <i class="bi bi-map me-1"></i>Offline Map Tiles
+                  </h6>
+                  <small class="text-muted">
+                    Map tiles you've already viewed are cached on this device so they work offline.
+                    Tiles are cached automatically as you browse, or you can pre-download a region.
+                  </small>
+                </div>
+                <div class="ms-3 d-flex gap-2 flex-shrink-0">
+                  <button type="button" class="btn btn-sm btn-primary"
+                          id="download-tiles-btn" style="white-space:nowrap;">
+                    <i class="bi bi-cloud-download me-1"></i>Download offline map
+                  </button>
+                  <button type="button" class="btn btn-sm btn-outline-danger"
+                          id="clear-tiles-btn" style="white-space:nowrap;">
+                    <i class="bi bi-trash3 me-1"></i>Clear cached tiles
+                  </button>
+                </div>
+              </div>
+              <div id="tile-cache-stats" class="small">
+                <div class="text-muted fst-italic">Loading…</div>
+              </div>
+            </div>
+          </div>
+        </div>
+      </div>
+    </div>
+  </div>
+
+  <!-- Download Offline Map modal -->
+  <div class="modal fade" id="offline-download-modal" tabindex="-1" aria-labelledby="offline-download-title" aria-hidden="true">
+    <div class="modal-dialog modal-dialog-centered modal-lg">
+      <div class="modal-content">
+        <div class="modal-header">
+          <h5 class="modal-title" id="offline-download-title">
+            <i class="bi bi-cloud-download me-2"></i>Download Offline Map
+          </h5>
+          <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close" id="offline-download-close-btn"></button>
+        </div>
+
+        <!-- Form view (shown until Start is clicked) -->
+        <div class="modal-body" id="offline-download-form-view">
+          <p class="text-muted small mb-3">
+            Pre-fetch map tiles so they're available when you're offline.
+            Only the OpenStreetMap and Topographic base maps can be downloaded;
+            other providers don't permit bulk caching.
+          </p>
+
+          <!-- Base map -->
+          <div class="mb-3">
+            <label for="offline-basemap-select" class="form-label fw-bold">Base map</label>
+            <select class="form-select form-select-sm" id="offline-basemap-select">
+              <option value="topo">Topographic</option>
+              <option value="osm">OpenStreetMap</option>
+            </select>
+          </div>
+
+          <!-- Area -->
+          <div class="mb-3">
+            <label class="form-label fw-bold mb-1">Area to download</label>
+            <div class="form-check">
+              <input class="form-check-input" type="radio" name="offline-area" id="offline-area-view" value="view" checked>
+              <label class="form-check-label" for="offline-area-view">
+                Current map view
+                <span class="text-muted small" id="offline-area-view-info"></span>
+              </label>
+            </div>
+            <div class="form-check">
+              <input class="form-check-input" type="radio" name="offline-area" id="offline-area-district" value="district">
+              <label class="form-check-label" for="offline-area-district">
+                District boundary
+                <span class="text-muted small" id="offline-area-district-info"></span>
+              </label>
+            </div>
+            <div class="form-check">
+              <input class="form-check-input" type="radio" name="offline-area" id="offline-area-ghana" value="ghana">
+              <label class="form-check-label" for="offline-area-ghana">
+                Entire Ghana <span class="text-muted small">(very large — only attempt over fast Wi-Fi)</span>
+              </label>
+            </div>
+          </div>
+
+          <!-- Zoom range -->
+          <div class="mb-3">
+            <label class="form-label fw-bold mb-1">Zoom levels</label>
+            <div class="row g-2 align-items-center">
+              <div class="col-auto"><label for="offline-min-zoom" class="form-label small mb-0">Min</label></div>
+              <div class="col-auto">
+                <input type="number" class="form-control form-control-sm" id="offline-min-zoom" min="6" max="19" value="10" style="width:5em;">
+              </div>
+              <div class="col-auto"><label for="offline-max-zoom" class="form-label small mb-0">Max</label></div>
+              <div class="col-auto">
+                <input type="number" class="form-control form-control-sm" id="offline-max-zoom" min="6" max="19" value="15" style="width:5em;">
+              </div>
+              <div class="col text-muted small">10 = regional · 13 = neighbourhood · 16 = building</div>
+            </div>
+          </div>
+
+          <!-- Estimate -->
+          <div class="alert alert-info py-2 px-3 mb-3" id="offline-estimate" style="font-size:0.9em;">
+            <strong>Estimated download:</strong>
+            <span id="offline-estimate-detail">Calculating…</span>
+          </div>
+
+          <!-- Acknowledgement -->
+          <div class="form-check mb-2">
+            <input class="form-check-input" type="checkbox" id="offline-ack-check">
+            <label class="form-check-label small" for="offline-ack-check">
+              I understand this counts against the tile provider's usage quota
+              and will use mobile data if I'm not on Wi-Fi.
+            </label>
+          </div>
+        </div>
+
+        <!-- Progress view (shown during download) -->
+        <div class="modal-body d-none" id="offline-download-progress-view">
+          <div class="text-center mb-3">
+            <div class="fs-5 fw-bold" id="offline-progress-percent">0%</div>
+            <div class="small text-muted" id="offline-progress-counts">0 of 0 tiles</div>
+          </div>
+          <div class="progress mb-3" style="height:1.25em;">
+            <div class="progress-bar progress-bar-striped progress-bar-animated"
+                 role="progressbar" id="offline-progress-bar"
+                 aria-valuemin="0" aria-valuemax="100" style="width:0%;"></div>
+          </div>
+          <div class="row text-center small text-muted">
+            <div class="col"><div class="fw-bold text-body" id="offline-progress-ok">0</div>fetched</div>
+            <div class="col"><div class="fw-bold text-body" id="offline-progress-failed">0</div>failed</div>
+            <div class="col"><div class="fw-bold text-body" id="offline-progress-eta">—</div>remaining</div>
+          </div>
+        </div>
+
+        <!-- Done view (shown after completion) -->
+        <div class="modal-body d-none" id="offline-download-done-view">
+          <div class="text-center py-3">
+            <i class="bi bi-check-circle-fill text-success" style="font-size:3rem;"></i>
+            <div class="fs-5 fw-bold mt-2" id="offline-done-title">Download complete</div>
+            <div class="text-muted" id="offline-done-detail"></div>
+          </div>
+        </div>
+
+        <div class="modal-footer">
+          <button type="button" class="btn btn-secondary" data-bs-dismiss="modal" id="offline-download-cancel-btn">
+            Cancel
+          </button>
+          <button type="button" class="btn btn-primary" id="offline-download-start-btn" disabled>
+            <i class="bi bi-cloud-download me-1"></i>Start download
+          </button>
+          <button type="button" class="btn btn-primary d-none" id="offline-download-close-done-btn" data-bs-dismiss="modal">
+            Close
+          </button>
+        </div>
+      </div>
+    </div>
+  </div>

  <!-- Polyfill crypto.randomUUID for non-secure contexts (HTTP) -->
  <!-- Must run before module imports (SQLocal/coincident require it) -->
--- a/main.js
+++ b/main.js
--- a/package-lock.json
+++ b/package-lock.json
@ -1,18 +1,21 @@
 {
-  "name": "lupmis-pwa",
+  "name": "lupmis2-pwa",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
-      "name": "lupmis-pwa",
+      "name": "lupmis2-pwa",
      "version": "1.0.0",
      "dependencies": {
        "@popperjs/core": "^2.11.8",
        "bootstrap": "^5.3.3",
        "bootstrap-icons": "^1.11.3",
+        "jspdf": "^4.2.1",
+        "jspdf-autotable": "^5.0.7",
        "ol": "^10.3.0",
        "ol-ext": "^4.0.24",
+        "shpjs": "^6.2.0",
        "sqlocal": "^0.16.0"
      },
      "devDependencies": {
@ -22,6 +25,15 @@
        "node": ">=18.0.0"
      }
    },
+    "node_modules/@babel/runtime": {
+      "version": "7.29.2",
+      "resolved": "https://registry.npmjs.org/@babel/runtime/-/runtime-7.29.2.tgz",
+      "integrity": "sha512-JiDShH45zKHWyGe4ZNVRrCjBz8Nh9TMmZG1kh4QTK8hCBTWBi8Da+i7s1fJw7/lYpM4ccepSNfqzZ/QvABBi5g==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=6.9.0"
+      }
+    },
    "node_modules/@esbuild/aix-ppc64": {
      "version": "0.25.12",
      "resolved": "https://registry.npmjs.org/@esbuild/aix-ppc64/-/aix-ppc64-0.25.12.tgz",
@ -795,12 +807,32 @@
      "devOptional": true,
      "license": "MIT"
    },
+    "node_modules/@types/pako": {
+      "version": "2.0.4",
+      "resolved": "https://registry.npmjs.org/@types/pako/-/pako-2.0.4.tgz",
+      "integrity": "sha512-VWDCbrLeVXJM9fihYodcLiIv0ku+AlOa/TQ1SvYOaBuyrSKgEcro95LJyIsJ4vSo6BXIxOKxiJAat04CmST9Fw==",
+      "license": "MIT"
+    },
+    "node_modules/@types/raf": {
+      "version": "3.4.3",
+      "resolved": "https://registry.npmjs.org/@types/raf/-/raf-3.4.3.tgz",
+      "integrity": "sha512-c4YAvMedbPZ5tEyxzQdMoOhhJ4RD3rngZIdwC2/qDN3d7JpEhB6fiBRKVY1lg5B7Wk+uPBjn5f39j1/2MY1oOw==",
+      "license": "MIT",
+      "optional": true
+    },
    "node_modules/@types/rbush": {
      "version": "4.0.0",
      "resolved": "https://registry.npmjs.org/@types/rbush/-/rbush-4.0.0.tgz",
      "integrity": "sha512-+N+2H39P8X+Hy1I5mC6awlTX54k3FhiUmvt7HWzGJZvF+syUAAxP/stwppS8JE84YHqFgRMv6fCy31202CMFxQ==",
      "license": "MIT"
    },
+    "node_modules/@types/trusted-types": {
+      "version": "2.0.7",
+      "resolved": "https://registry.npmjs.org/@types/trusted-types/-/trusted-types-2.0.7.tgz",
+      "integrity": "sha512-ScaPdn1dQczgbl0QFTeTOmVHFULt394XJgOQNoyVhZ6r2vLnMLJfBPd53SB52T/3G36VI1/g2MZaX0cwDuXsfw==",
+      "license": "MIT",
+      "optional": true
+    },
    "node_modules/@ungap/structured-clone": {
      "version": "1.3.0",
      "resolved": "https://registry.npmjs.org/@ungap/structured-clone/-/structured-clone-1.3.0.tgz",
@ -813,6 +845,16 @@
      "integrity": "sha512-g7f0IkJdPW2xhY7H4iE72DAsIyfuwEFc6JWc2tYFwKDMWWAF699vGjrM348cwQuOXgHpe1gWFe+Eiyjx/ewvvw==",
      "license": "ISC"
    },
+    "node_modules/base64-arraybuffer": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/base64-arraybuffer/-/base64-arraybuffer-1.0.2.tgz",
+      "integrity": "sha512-I3yl4r9QB5ZRY3XuJVEPfc2XhZO6YweFPI+UovAzn+8/hb3oJ6lnysaFcjVpkCPfVWFUDvoZ8kmVDP7WyRtYtQ==",
+      "license": "MIT",
+      "optional": true,
+      "engines": {
+        "node": ">= 0.6.0"
+      }
+    },
    "node_modules/bootstrap": {
      "version": "5.3.8",
      "resolved": "https://registry.npmjs.org/bootstrap/-/bootstrap-5.3.8.tgz",
@ -848,6 +890,32 @@
      ],
      "license": "MIT"
    },
+    "node_modules/but-unzip": {
+      "version": "0.1.10",
+      "resolved": "https://registry.npmjs.org/but-unzip/-/but-unzip-0.1.10.tgz",
+      "integrity": "sha512-hLfQ9WlUimmv/okzsRl6AYG3Ew5HNWhWgUslSR93FsDdeL0MAoQvmC/BJfs35lqEAO5t/QD7Y4vCFcPJtijt3A==",
+      "license": "Apache-2.0"
+    },
+    "node_modules/canvg": {
+      "version": "3.0.11",
+      "resolved": "https://registry.npmjs.org/canvg/-/canvg-3.0.11.tgz",
+      "integrity": "sha512-5ON+q7jCTgMp9cjpu4Jo6XbvfYwSB2Ow3kzHKfIyJfaCAOHLbdKPQqGKgfED/R5B+3TFFfe8pegYA+b423SRyA==",
+      "license": "MIT",
+      "optional": true,
+      "dependencies": {
+        "@babel/runtime": "^7.12.5",
+        "@types/raf": "^3.4.0",
+        "core-js": "^3.8.3",
+        "raf": "^3.4.1",
+        "regenerator-runtime": "^0.13.7",
+        "rgbcolor": "^1.0.1",
+        "stackblur-canvas": "^2.0.0",
+        "svg-pathdata": "^6.0.3"
+      },
+      "engines": {
+        "node": ">=10.0.0"
+      }
+    },
    "node_modules/coincident": {
      "version": "1.2.3",
      "resolved": "https://registry.npmjs.org/coincident/-/coincident-1.2.3.tgz",
@ -863,6 +931,38 @@
        "ws": "^8.16.0"
      }
    },
+    "node_modules/core-js": {
+      "version": "3.49.0",
+      "resolved": "https://registry.npmjs.org/core-js/-/core-js-3.49.0.tgz",
+      "integrity": "sha512-es1U2+YTtzpwkxVLwAFdSpaIMyQaq0PBgm3YD1W3Qpsn1NAmO3KSgZfu+oGSWVu6NvLHoHCV/aYcsE5wiB7ALg==",
+      "hasInstallScript": true,
+      "license": "MIT",
+      "optional": true,
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/core-js"
+      }
+    },
+    "node_modules/css-line-break": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/css-line-break/-/css-line-break-2.1.0.tgz",
+      "integrity": "sha512-FHcKFCZcAha3LwfVBhCQbW2nCNbkZXn7KVUJcsT5/P8YmfsVja0FMPJr0B903j/E69HUphKiV9iQArX8SDYA4w==",
+      "license": "MIT",
+      "optional": true,
+      "dependencies": {
+        "utrie": "^1.0.2"
+      }
+    },
+    "node_modules/dompurify": {
+      "version": "3.3.3",
+      "resolved": "https://registry.npmjs.org/dompurify/-/dompurify-3.3.3.tgz",
+      "integrity": "sha512-Oj6pzI2+RqBfFG+qOaOLbFXLQ90ARpcGG6UePL82bJLtdsa6CYJD7nmiU8MW9nQNOtCHV3lZ/Bzq1X0QYbBZCA==",
+      "license": "(MPL-2.0 OR Apache-2.0)",
+      "optional": true,
+      "optionalDependencies": {
+        "@types/trusted-types": "^2.0.7"
+      }
+    },
    "node_modules/earcut": {
      "version": "3.0.2",
      "resolved": "https://registry.npmjs.org/earcut/-/earcut-3.0.2.tgz",
@ -911,6 +1011,17 @@
        "@esbuild/win32-x64": "0.25.12"
      }
    },
+    "node_modules/fast-png": {
+      "version": "6.4.0",
+      "resolved": "https://registry.npmjs.org/fast-png/-/fast-png-6.4.0.tgz",
+      "integrity": "sha512-kAqZq1TlgBjZcLr5mcN6NP5Rv4V2f22z00c3g8vRrwkcqjerx7BEhPbOnWCPqaHUl2XWQBJQvOT/FQhdMT7X/Q==",
+      "license": "MIT",
+      "dependencies": {
+        "@types/pako": "^2.0.3",
+        "iobuffer": "^5.3.2",
+        "pako": "^2.1.0"
+      }
+    },
    "node_modules/fdir": {
      "version": "6.5.0",
      "resolved": "https://registry.npmjs.org/fdir/-/fdir-6.5.0.tgz",
@ -929,6 +1040,12 @@
        }
      }
    },
+    "node_modules/fflate": {
+      "version": "0.8.2",
+      "resolved": "https://registry.npmjs.org/fflate/-/fflate-0.8.2.tgz",
+      "integrity": "sha512-cPJU47OaAoCbg0pBvzsgpTPhmhqI5eJjh/JIu8tPj5q+T7iLvW/JAYUqmE7KOB4R1ZyEhzBaIQpQpardBF5z8A==",
+      "license": "MIT"
+    },
    "node_modules/fsevents": {
      "version": "2.3.3",
      "resolved": "https://registry.npmjs.org/fsevents/-/fsevents-2.3.3.tgz",
@ -968,12 +1085,64 @@
        "node": ">=10.19"
      }
    },
+    "node_modules/html2canvas": {
+      "version": "1.4.1",
+      "resolved": "https://registry.npmjs.org/html2canvas/-/html2canvas-1.4.1.tgz",
+      "integrity": "sha512-fPU6BHNpsyIhr8yyMpTLLxAbkaK8ArIBcmZIRiBLiDhjeqvXolaEmDGmELFuX9I4xDcaKKcJl+TKZLqruBbmWA==",
+      "license": "MIT",
+      "optional": true,
+      "dependencies": {
+        "css-line-break": "^2.1.0",
+        "text-segmentation": "^1.0.3"
+      },
+      "engines": {
+        "node": ">=8.0.0"
+      }
+    },
+    "node_modules/iobuffer": {
+      "version": "5.4.0",
+      "resolved": "https://registry.npmjs.org/iobuffer/-/iobuffer-5.4.0.tgz",
+      "integrity": "sha512-DRebOWuqDvxunfkNJAlc3IzWIPD5xVxwUNbHr7xKB8E6aLJxIPfNX3CoMJghcFjpv6RWQsrcJbghtEwSPoJqMA==",
+      "license": "MIT"
+    },
+    "node_modules/jspdf": {
+      "version": "4.2.1",
+      "resolved": "https://registry.npmjs.org/jspdf/-/jspdf-4.2.1.tgz",
+      "integrity": "sha512-YyAXyvnmjTbR4bHQRLzex3CuINCDlQnBqoSYyjJwTP2x9jDLuKDzy7aKUl0hgx3uhcl7xzg32agn5vlie6HIlQ==",
+      "license": "MIT",
+      "dependencies": {
+        "@babel/runtime": "^7.28.6",
+        "fast-png": "^6.2.0",
+        "fflate": "^0.8.1"
+      },
+      "optionalDependencies": {
+        "canvg": "^3.0.11",
+        "core-js": "^3.6.0",
+        "dompurify": "^3.3.1",
+        "html2canvas": "^1.0.0-rc.5"
+      }
+    },
+    "node_modules/jspdf-autotable": {
+      "version": "5.0.7",
+      "resolved": "https://registry.npmjs.org/jspdf-autotable/-/jspdf-autotable-5.0.7.tgz",
+      "integrity": "sha512-2wr7H6liNDBYNwt25hMQwXkEWFOEopgKIvR1Eukuw6Zmprm/ZcnmLTQEjW7Xx3FCbD3v7pflLcnMAv/h1jFDQw==",
+      "license": "MIT",
+      "peerDependencies": {
+        "jspdf": "^2 || ^3 || ^4"
+      }
+    },
    "node_modules/lerc": {
      "version": "3.0.0",
      "resolved": "https://registry.npmjs.org/lerc/-/lerc-3.0.0.tgz",
      "integrity": "sha512-Rm4J/WaHhRa93nCN2mwWDZFoRVF18G1f47C+kvQWyHGEZxFpTUi73p7lMVSAndyxGt6lJ2/CFbOcf9ra5p8aww==",
      "license": "Apache-2.0"
    },
+    "node_modules/mgrs": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/mgrs/-/mgrs-1.0.0.tgz",
+      "integrity": "sha512-awNbTOqCxK1DBGjalK3xqWIstBZgN6fxsMSiXLs9/spqWkF2pAhb2rrYCFSsr1/tT7PhcDGjZndG8SWYn0byYA==",
+      "license": "MIT"
+    },
    "node_modules/nanoid": {
      "version": "3.3.11",
      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.11.tgz",
@ -1031,6 +1200,12 @@
      "integrity": "sha512-Tz11t3uKztEW5FEVZnj1ox8GKblWn+PvHY9TmJV5Mll2uHEwRdR/5Li1OlXoECjLYkApdhWy44ocONwXLiKO5A==",
      "license": "MIT"
    },
+    "node_modules/parsedbf": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/parsedbf/-/parsedbf-2.0.0.tgz",
+      "integrity": "sha512-WNjKn/cwgGBkXqQLif+2VMEahcRHkBRU0/RfBWZ7Vj7snRNNW63yW1mVuuHRDyXTRxuGCzAHHBcr/Fn+U/bXjQ==",
+      "license": "MIT"
+    },
    "node_modules/pbf": {
      "version": "4.0.1",
      "resolved": "https://registry.npmjs.org/pbf/-/pbf-4.0.1.tgz",
@ -1043,6 +1218,13 @@
        "pbf": "bin/pbf"
      }
    },
+    "node_modules/performance-now": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/performance-now/-/performance-now-2.1.0.tgz",
+      "integrity": "sha512-7EAHlyLHI56VEIdK57uwHdHKIaAGbnXPiw0yWbarQZOKaKpvUIgW0jWRVLiatnM+XXlSwsanIBH/hzGMJulMow==",
+      "license": "MIT",
+      "optional": true
+    },
    "node_modules/picocolors": {
      "version": "1.1.1",
      "resolved": "https://registry.npmjs.org/picocolors/-/picocolors-1.1.1.tgz",
@ -1092,6 +1274,19 @@
        "node": "^10 || ^12 || >=14"
      }
    },
+    "node_modules/proj4": {
+      "version": "2.20.3",
+      "resolved": "https://registry.npmjs.org/proj4/-/proj4-2.20.3.tgz",
+      "integrity": "sha512-uKJXnf/RkHhExxnWHqQqy2J1bPc5Qo8XSGzrMSJTdPWUQDo1DkunIRBfAS0crQaP9bZCSKNjqYJdYWVov0hDXw==",
+      "license": "MIT",
+      "dependencies": {
+        "mgrs": "1.0.0",
+        "wkt-parser": "^1.5.3"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ahocevar"
+      }
+    },
    "node_modules/protocol-buffers-schema": {
      "version": "3.6.0",
      "resolved": "https://registry.npmjs.org/protocol-buffers-schema/-/protocol-buffers-schema-3.6.0.tgz",
@ -1122,6 +1317,16 @@
      "integrity": "sha512-XdjUArbK4Bm5fLLvlm5KpTFOiOThgfWWI4axAZDWg4E/0mKdZyI9tNEfds27qCi1ze/vwTR16kvmmGhRra3c2g==",
      "license": "ISC"
    },
+    "node_modules/raf": {
+      "version": "3.4.1",
+      "resolved": "https://registry.npmjs.org/raf/-/raf-3.4.1.tgz",
+      "integrity": "sha512-Sq4CW4QhwOHE8ucn6J34MqtZCeWFP2aQSmrlroYgqAV1PjStIhJXxYuTgUIfkEk7zTLjmIjLmU5q+fbD1NnOJA==",
+      "license": "MIT",
+      "optional": true,
+      "dependencies": {
+        "performance-now": "^2.1.0"
+      }
+    },
    "node_modules/rbush": {
      "version": "4.0.1",
      "resolved": "https://registry.npmjs.org/rbush/-/rbush-4.0.1.tgz",
@ -1131,6 +1336,13 @@
        "quickselect": "^3.0.0"
      }
    },
+    "node_modules/regenerator-runtime": {
+      "version": "0.13.11",
+      "resolved": "https://registry.npmjs.org/regenerator-runtime/-/regenerator-runtime-0.13.11.tgz",
+      "integrity": "sha512-kY1AZVr2Ra+t+piVaJ4gxaFaReZVH40AKNo7UCX6W+dEwBo/2oZJzqfuN1qLq1oL45o56cPaTXELwrTh8Fpggg==",
+      "license": "MIT",
+      "optional": true
+    },
    "node_modules/resolve-protobuf-schema": {
      "version": "2.1.0",
      "resolved": "https://registry.npmjs.org/resolve-protobuf-schema/-/resolve-protobuf-schema-2.1.0.tgz",
@ -1140,6 +1352,16 @@
        "protocol-buffers-schema": "^3.3.1"
      }
    },
+    "node_modules/rgbcolor": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/rgbcolor/-/rgbcolor-1.0.1.tgz",
+      "integrity": "sha512-9aZLIrhRaD97sgVhtJOW6ckOEh6/GnvQtdVNfdZ6s67+3/XwLS9lBcQYzEEhYVeUowN7pRzMLsyGhK2i/xvWbw==",
+      "license": "MIT OR SEE LICENSE IN FEEL-FREE.md",
+      "optional": true,
+      "engines": {
+        "node": ">= 0.8.15"
+      }
+    },
    "node_modules/rollup": {
      "version": "4.55.3",
      "resolved": "https://registry.npmjs.org/rollup/-/rollup-4.55.3.tgz",
@ -1185,6 +1407,17 @@
        "fsevents": "~2.3.2"
      }
    },
+    "node_modules/shpjs": {
+      "version": "6.2.0",
+      "resolved": "https://registry.npmjs.org/shpjs/-/shpjs-6.2.0.tgz",
+      "integrity": "sha512-8cR/RKYHQepmVyBMtzZQ+1bnSbWrtLXS6aoEJmpUlOSHtSUddterebVxYmIWq2g9kOEX9jm2kjHiikyPX7cNQA==",
+      "license": "MIT",
+      "dependencies": {
+        "but-unzip": "^0.1.4",
+        "parsedbf": "^2.0.0",
+        "proj4": "^2.1.4"
+      }
+    },
    "node_modules/source-map-js": {
      "version": "1.2.1",
      "resolved": "https://registry.npmjs.org/source-map-js/-/source-map-js-1.2.1.tgz",
@ -1237,6 +1470,36 @@
        }
      }
    },
+    "node_modules/stackblur-canvas": {
+      "version": "2.7.0",
+      "resolved": "https://registry.npmjs.org/stackblur-canvas/-/stackblur-canvas-2.7.0.tgz",
+      "integrity": "sha512-yf7OENo23AGJhBriGx0QivY5JP6Y1HbrrDI6WLt6C5auYZXlQrheoY8hD4ibekFKz1HOfE48Ww8kMWMnJD/zcQ==",
+      "license": "MIT",
+      "optional": true,
+      "engines": {
+        "node": ">=0.1.14"
+      }
+    },
+    "node_modules/svg-pathdata": {
+      "version": "6.0.3",
+      "resolved": "https://registry.npmjs.org/svg-pathdata/-/svg-pathdata-6.0.3.tgz",
+      "integrity": "sha512-qsjeeq5YjBZ5eMdFuUa4ZosMLxgr5RZ+F+Y1OrDhuOCEInRMA3x74XdBtggJcj9kOeInz0WE+LgCPDkZFlBYJw==",
+      "license": "MIT",
+      "optional": true,
+      "engines": {
+        "node": ">=12.0.0"
+      }
+    },
+    "node_modules/text-segmentation": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/text-segmentation/-/text-segmentation-1.0.3.tgz",
+      "integrity": "sha512-iOiPUo/BGnZ6+54OsWxZidGCsdU8YbE4PSpdPinp7DeMtUJNJBoJ/ouUSTJjHkh1KntHaltHl/gDs2FC4i5+Nw==",
+      "license": "MIT",
+      "optional": true,
+      "dependencies": {
+        "utrie": "^1.0.2"
+      }
+    },
    "node_modules/tinyglobby": {
      "version": "0.2.15",
      "resolved": "https://registry.npmjs.org/tinyglobby/-/tinyglobby-0.2.15.tgz",
@ -1254,6 +1517,16 @@
        "url": "https://github.com/sponsors/SuperchupuDev"
      }
    },
+    "node_modules/utrie": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/utrie/-/utrie-1.0.2.tgz",
+      "integrity": "sha512-1MLa5ouZiOmQzUbjbu9VmjLzn1QLXBhwpUa7kdLUQK+KQ5KA9I1vk5U4YHe/X2Ch7PYnJfWuWT+VbuxbGwljhw==",
+      "license": "MIT",
+      "optional": true,
+      "dependencies": {
+        "base64-arraybuffer": "^1.0.2"
+      }
+    },
    "node_modules/vite": {
      "version": "6.4.1",
      "resolved": "https://registry.npmjs.org/vite/-/vite-6.4.1.tgz",
@ -1335,6 +1608,12 @@
      "integrity": "sha512-RiMReJrTAiA+mBjGONMnjVDP2u3p9R1vkcGz6gDIrOMT3oGuYwX2WRMYI9ipkphSuE5XKEhydbhNEJh4NY9mlw==",
      "license": "Apache-2.0"
    },
+    "node_modules/wkt-parser": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/wkt-parser/-/wkt-parser-1.5.3.tgz",
+      "integrity": "sha512-myla+RrMj+WTlnHc8Y4HEwjBcBF9dqJ3vjff/zmlrn9V3OKOM1mZVIyNjlPEmOM9Jjr/PPut0tnaTs9NyHcK8Q==",
+      "license": "MIT"
+    },
    "node_modules/ws": {
      "version": "8.19.0",
      "resolved": "https://registry.npmjs.org/ws/-/ws-8.19.0.tgz",
--- a/package.json
+++ b/package.json
@ -9,11 +9,14 @@
    "preview": "vite preview"
  },
  "dependencies": {
+    "@popperjs/core": "^2.11.8",
    "bootstrap": "^5.3.3",
    "bootstrap-icons": "^1.11.3",
-    "@popperjs/core": "^2.11.8",
+    "jspdf": "^4.2.1",
+    "jspdf-autotable": "^5.0.7",
    "ol": "^10.3.0",
    "ol-ext": "^4.0.24",
+    "shpjs": "^6.2.0",
    "sqlocal": "^0.16.0"
  },
  "devDependencies": {
--- a/public/fonts/bebas-neue-latin-ext.woff2
+++ b/public/fonts/bebas-neue-latin-ext.woff2
--- a/public/fonts/bebas-neue-latin.woff2
+++ b/public/fonts/bebas-neue-latin.woff2
--- a/public/fonts/exo-latin-ext.woff2
+++ b/public/fonts/exo-latin-ext.woff2
--- a/public/fonts/exo-latin.woff2
+++ b/public/fonts/exo-latin.woff2
--- a/public/fonts/exo-vietnamese.woff2
+++ b/public/fonts/exo-vietnamese.woff2
--- a/public/icons/README.txt
+++ b/public/icons/README.txt
@ -1 +0,0 @@
-Place PWA icons here (icon-72.png, icon-96.png, icon-128.png, icon-144.png, icon-152.png, icon-192.png, icon-384.png, icon-512.png)
--- a/public/icons/luspa-128x128.png
+++ b/public/icons/luspa-128x128.png
--- a/public/icons/luspa-144x144.png
+++ b/public/icons/luspa-144x144.png
--- a/public/icons/luspa-152x152.png
+++ b/public/icons/luspa-152x152.png
--- a/public/icons/luspa-384x384.png
+++ b/public/icons/luspa-384x384.png
--- a/public/icons/luspa-72x72.png
+++ b/public/icons/luspa-72x72.png
--- a/public/icons/luspa-96x96.png
+++ b/public/icons/luspa-96x96.png
--- a/public/icons/luspa-pdf.jpg
+++ b/public/icons/luspa-pdf.jpg
--- a/public/icons/luspa.icon/Assets/luspalogo.png
+++ b/public/icons/luspa.icon/Assets/luspalogo.png
--- a/public/icons/luspa.icon/icon.json
+++ b/public/icons/luspa.icon/icon.json
@ -1,49 +0,0 @@
-{
-  "fill" : {
-    "linear-gradient" : [
-      "display-p3:0.10199,0.05884,0.32544,1.00000",
-      "display-p3:0.27051,0.49023,0.74121,1.00000"
-    ],
-    "orientation" : {
-      "start" : {
-        "x" : 0.5,
-        "y" : 0
-      },
-      "stop" : {
-        "x" : 0.5,
-        "y" : 0.7
-      }
-    }
-  },
-  "groups" : [
-    {
-      "layers" : [
-        {
-          "image-name" : "luspalogo.png",
-          "name" : "luspalogo",
-          "position" : {
-            "scale" : 1.8,
-            "translation-in-points" : [
-              0,
-              0
-            ]
-          }
-        }
-      ],
-      "shadow" : {
-        "kind" : "neutral",
-        "opacity" : 0.5
-      },
-      "translucency" : {
-        "enabled" : true,
-        "value" : 0.5
-      }
-    }
-  ],
-  "supported-platforms" : {
-    "circles" : [
-      "watchOS"
-    ],
-    "squares" : "shared"
-  }
-}
--- a/public/manifest.json
+++ b/public/manifest.json
@ -1,58 +1,58 @@
 {
  "name": "LUPMIS2 Drawing Tools",
-  "short_name": "LUPMIS",
+  "short_name": "LUPMIS2",
  "description": "Map and GIS functions for Land Use Planning in Ghana",
-  "start_url": "/",
-  "scope": "/",
+  "start_url": "./",
+  "scope": "./",
  "display": "standalone",
  "background_color": "#ffffff",
  "theme_color": "#005eb8",
  "orientation": "any",
  "icons": [
    {
-      "src": "/icons/icon-72.png",
+      "src": "./icons/luspa-72x72.png",
      "sizes": "72x72",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/icon-96.png",
+      "src": "./icons/luspa-96x96.png",
      "sizes": "96x96",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/icon-128.png",
+      "src": "./icons/luspa-128x128.png",
      "sizes": "128x128",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/icon-144.png",
+      "src": "./icons/luspa-144x144.png",
      "sizes": "144x144",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/icon-152.png",
+      "src": "./icons/luspa-152x152.png",
      "sizes": "152x152",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/luspa-192x192.png",
+      "src": "./icons/luspa-192x192.png",
      "sizes": "192x192",
      "type": "image/png",
      "purpose": "any maskable"
    },
    {
-      "src": "/icons/icon-384.png",
+      "src": "./icons/luspa-384x384.png",
      "sizes": "384x384",
      "type": "image/png",
      "purpose": "any"
    },
    {
-      "src": "/icons/luspa-512x512.png",
+      "src": "./icons/luspa-512x512.png",
      "sizes": "512x512",
      "type": "image/png",
      "purpose": "any maskable"
--- a/public/sw.js
+++ b/public/sw.js
@ -1,29 +1,81 @@
 /**
 * Service Worker
- * 
+ *
 * Handles caching of:
 * - App shell (HTML, CSS, JS)
- * - Map tiles (runtime caching)
+ * - Map tiles (passive runtime caching, per-host buckets)
 * - API responses (network-first)
- * 
+ *
 * Note: Database operations are handled by the SharedWorker (shared-db-worker.js),
 *       NOT by this service worker. They serve different purposes:
 *       - Service Worker: Caching, offline asset serving, push notifications
 *       - SharedWorker: Shared database connection across tabs
 */

-const CACHE_VERSION = 'v1';
-const SHELL_CACHE = `shell-${CACHE_VERSION}`;
-const TILES_CACHE = `tiles-${CACHE_VERSION}`;
+// v3: lower per-cache limits (5000 → 1500) and counter-based eviction to
+//     prevent Safari memory-pressure reloads.
+// v4: raise OSM and Topographic limits to 8000 to support active offline
+//     downloads (Phase 2). Other providers stay at 1500.
+const CACHE_VERSION = 'v4';
+const SHELL_CACHE   = `shell-${CACHE_VERSION}`;
 const MODULES_CACHE = `modules-${CACHE_VERSION}`;
-const API_CACHE = `api-${CACHE_VERSION}`;
+const API_CACHE     = `api-${CACHE_VERSION}`;

-// Maximum number of tiles to cache
-const MAX_TILES = 500;
+// ----------------------------------------------------------------------------
+// Tile caches — one per provider so users can clear them independently.
+// Limits are per-cache (not global). 5 000 tiles ≈ ~150 MB at ~30 KB/tile,
+// which covers a Ghana district at zoom 10–15 (typical field-work range).
+// ----------------------------------------------------------------------------
+const TILES_OSM         = `tiles-osm-${CACHE_VERSION}`;
+const TILES_TOPO        = `tiles-topo-${CACHE_VERSION}`;
+const TILES_SATELLITE   = `tiles-satellite-${CACHE_VERSION}`;
+const TILES_CARTO_LIGHT = `tiles-carto-light-${CACHE_VERSION}`;
+const TILES_CARTO_DARK  = `tiles-carto-dark-${CACHE_VERSION}`;

-// App shell assets - precached on install
-// Vite will generate hashed filenames, so we cache the entry points
-// and let the browser handle the hashed assets
+// Per-provider tile limits.
+//   • OSM and Topographic are the providers offered for active offline
+//     download (Phase 2 dialog), so they get a higher cap (~240 MB each at
+//     ~30 KB/tile) — enough for a typical Ghana district at zoom 10–15.
+//   • The other providers serve passive caching only (whatever the user has
+//     already viewed), so 1 500 tiles ≈ 45 MB is plenty.
+//
+// Total max ≈ 5 × ~150 MB = ~750 MB on disk in the worst case, but only the
+// two downloadable buckets are likely to fill. Eviction sweeps run every 100
+// inserts (see EVICTION_CHECK_INTERVAL) so memory pressure stays bounded.
+const TILE_LIMITS = {
+  [TILES_OSM]:         8000,
+  [TILES_TOPO]:        8000,
+  [TILES_SATELLITE]:   1500,
+  [TILES_CARTO_LIGHT]: 1500,
+  [TILES_CARTO_DARK]:  1500,
+};
+
+// Per-cache running insert counter, in memory. Avoids calling cache.keys()
+// (which materialises every Request object in the cache) on every put — that
+// was the cause of the Safari "reloaded due to memory pressure" failures.
+//
+// We only run a real eviction sweep every EVICTION_CHECK_INTERVAL inserts.
+const _tileInsertCounters = new Map(); // cacheName → number of inserts since last eviction
+const EVICTION_CHECK_INTERVAL = 100;
+
+// Friendly name shown in the UI (matches Settings card labels)
+const TILE_CACHE_LABELS = {
+  [TILES_OSM]:         'OpenStreetMap',
+  [TILES_TOPO]:        'Topographic',
+  [TILES_SATELLITE]:   'Satellite',
+  [TILES_CARTO_LIGHT]: 'Carto Light',
+  [TILES_CARTO_DARK]:  'Carto Dark',
+};
+
+const ALL_TILE_CACHES = Object.keys(TILE_LIMITS);
+
+// Approximate average tile size — used for storage estimation.
+// Real measurements: PNG tiles range 5–80 KB; 30 KB is a good middle ground.
+const AVG_TILE_BYTES = 30 * 1024;
+
+// ----------------------------------------------------------------------------
+// App shell assets — precached on install.
+// ----------------------------------------------------------------------------
 const SHELL_ASSETS = [
  '/',
  '/index.html',
@ -37,7 +89,7 @@ const SHELL_ASSETS = [

 self.addEventListener('install', (event) => {
  console.log('[SW] Installing...');
-  
+
  event.waitUntil(
    caches.open(SHELL_CACHE)
      .then((cache) => {
@ -54,18 +106,26 @@ self.addEventListener('install', (event) => {

 self.addEventListener('activate', (event) => {
  console.log('[SW] Activating...');
-  
+
  event.waitUntil(
    caches.keys()
      .then((cacheNames) => {
+        // Build the set of caches that should remain
+        const keep = new Set([SHELL_CACHE, MODULES_CACHE, API_CACHE, ...ALL_TILE_CACHES]);
+
        return Promise.all(
          cacheNames
+            // Delete anything that:
+            //  • belongs to one of our managed cache prefixes (shell-, tiles-, modules-, api-)
+            //  • but is NOT in the current keep set
+            // This includes the legacy "tiles-v1" single bucket.
            .filter((name) => {
-              // Delete old version caches
-              return (name.startsWith('shell-') && name !== SHELL_CACHE) ||
-                     (name.startsWith('tiles-') && name !== TILES_CACHE) ||
-                     (name.startsWith('modules-') && name !== MODULES_CACHE) ||
-                     (name.startsWith('api-') && name !== API_CACHE);
+              const isOurs =
+                name.startsWith('shell-') ||
+                name.startsWith('tiles-') ||
+                name.startsWith('modules-') ||
+                name.startsWith('api-');
+              return isOurs && !keep.has(name);
            })
            .map((name) => {
              console.log('[SW] Deleting old cache:', name);
@ -84,17 +144,28 @@ self.addEventListener('activate', (event) => {
 self.addEventListener('fetch', (event) => {
  const request = event.request;
  const url = new URL(request.url);
-  
+
  // Only handle GET requests
  if (request.method !== 'GET') return;
-  
+
  // Skip chrome-extension and other non-http(s) requests
  if (!url.protocol.startsWith('http')) return;
-  
-  // Route to appropriate caching strategy
-  if (isMapTile(url)) {
-    event.respondWith(cacheThenNetwork(request, TILES_CACHE, MAX_TILES));
-  } else if (isApiRequest(url)) {
+
+  // Skip worker files and Vite dev-server node_modules requests —
+  // intercepting these breaks module workers (e.g. SQLocal/SQLite).
+  if (url.pathname.includes('node_modules') ||
+      url.search.includes('worker_file') ||
+      request.destination === 'worker') return;
+
+  // ----- TILE REQUESTS — passive cache-then-network (per-host bucket) -----
+  const tileCache = getTileCacheName(url);
+  if (tileCache) {
+    event.respondWith(tileCacheThenNetwork(request, tileCache));
+    return;
+  }
+
+  // ----- OTHER ROUTES (unchanged) -----
+  if (isApiRequest(url)) {
    event.respondWith(networkFirst(request, API_CACHE));
  } else if (isModuleAsset(url)) {
    event.respondWith(staleWhileRevalidate(request, MODULES_CACHE));
@ -108,15 +179,36 @@ self.addEventListener('fetch', (event) => {
 // URL CLASSIFICATION
 // ============================================================================

-function isMapTile(url) {
-  // Common tile server patterns for all our base maps
-  return url.hostname.includes('tile.openstreetmap.org') ||
-         url.hostname.includes('opentopomap.org') ||
-         url.hostname.includes('arcgisonline.com') ||
-         url.hostname.includes('basemaps.cartocdn.com') ||
-         url.hostname.includes('tiles.') ||
-         url.pathname.match(/\/\d+\/\d+\/\d+\.(png|jpg|pbf)$/) ||
-         url.pathname.match(/\/tile\/\d+\/\d+\/\d+/);
+/**
+ * Classify a URL into the appropriate tile cache.
+ * Returns `null` for non-tile requests, or for tile providers we deliberately
+ * do NOT cache (e.g. Google — caching is forbidden by their ToS).
+ */
+function getTileCacheName(url) {
+  const host = url.hostname;
+
+  // OpenStreetMap — tile.openstreetmap.org and a/b/c subdomains
+  if (host.endsWith('tile.openstreetmap.org')) return TILES_OSM;
+
+  // OpenTopoMap — a/b/c.tile.opentopomap.org
+  if (host.endsWith('tile.opentopomap.org') || host.endsWith('opentopomap.org')) return TILES_TOPO;
+
+  // Carto Basemaps — light_all / dark_all distinguished by path
+  if (host.endsWith('basemaps.cartocdn.com')) {
+    if (url.pathname.includes('/light_all/')) return TILES_CARTO_LIGHT;
+    if (url.pathname.includes('/dark_all/'))  return TILES_CARTO_DARK;
+    return null; // unknown Carto style
+  }
+
+  // Esri — server.arcgisonline.com
+  if (host.endsWith('arcgisonline.com')) return TILES_SATELLITE;
+
+  // Google — caching forbidden by ToS, do not store
+  if (host.endsWith('google.com') || host.endsWith('googleapis.com')) return null;
+
+  // Other tile providers (WMS endpoints, OWS, custom) — not cached at this layer
+  // (the user's "online only" toast handles those).
+  return null;
 }

 function isApiRequest(url) {
@ -129,7 +221,6 @@ function isModuleAsset(url) {
 }

 function isAppAsset(url) {
-  // Same origin, common asset extensions
  return url.origin === self.location.origin &&
         (url.pathname.endsWith('.html') ||
          url.pathname.endsWith('.css') ||
@ -144,13 +235,13 @@ function isAppAsset(url) {
 // ============================================================================

 /**
- * Cache First - Use cache, fallback to network
- * Best for: App shell, static assets
+ * Cache First — Use cache, fallback to network.
+ * Best for: App shell, static assets.
 */
 async function cacheFirst(request, cacheName) {
  const cached = await caches.match(request);
  if (cached) return cached;
-  
+
  try {
    const response = await fetch(request);
    if (response.ok) {
@ -159,7 +250,6 @@ async function cacheFirst(request, cacheName) {
    }
    return response;
  } catch (error) {
-    // Return offline page for navigation requests
    if (request.mode === 'navigate') {
      return caches.match('/offline.html');
    }
@ -168,8 +258,8 @@ async function cacheFirst(request, cacheName) {
 }

 /**
- * Network First - Try network, fallback to cache
- * Best for: API requests, dynamic content
+ * Network First — Try network, fallback to cache.
+ * Best for: API requests, dynamic content.
 */
 async function networkFirst(request, cacheName) {
  try {
@ -187,89 +277,141 @@ async function networkFirst(request, cacheName) {
 }

 /**
- * Stale While Revalidate - Return cache immediately, update in background
- * Best for: Module assets, frequently updated content
+ * Stale While Revalidate — Return cache immediately, update in background.
+ * Best for: Module assets, frequently updated content.
 */
 async function staleWhileRevalidate(request, cacheName) {
  const cache = await caches.open(cacheName);
  const cached = await cache.match(request);
-  
+
  const fetchPromise = fetch(request).then((response) => {
    if (response.ok) {
      cache.put(request, response.clone());
    }
    return response;
  }).catch(() => cached);
-  
+
  return cached || fetchPromise;
 }

 /**
- * Cache Then Network with limit - Cache tiles with size limit
- * Best for: Map tiles
+ * Tile Cache then Network — Per-host bucket with size limit.
+ * Cache first; on miss, fetch from network and store.
+ *
+ * Memory-conservative eviction:
+ *   • Increments an in-memory counter on every successful insert
+ *   • Only calls cache.keys() (which materialises all Request objects) every
+ *     EVICTION_CHECK_INTERVAL inserts — so the cost is amortised
+ *   • Eviction drops the oldest 10 % when over the per-host limit
+ *
+ * On network failure (offline), serves a 408 so the map renders a blank tile
+ * rather than throwing.
 */
-async function cacheThenNetwork(request, cacheName, maxItems) {
+async function tileCacheThenNetwork(request, cacheName) {
  const cache = await caches.open(cacheName);
  const cached = await cache.match(request);
-  
  if (cached) return cached;
-  
+
  try {
    const response = await fetch(request);
-    
+
    if (response.ok) {
-      // Check cache size and trim if needed
-      const keys = await cache.keys();
-      if (keys.length >= maxItems) {
-        // Remove oldest entries (first 10%)
-        const toDelete = keys.slice(0, Math.ceil(maxItems * 0.1));
-        await Promise.all(toDelete.map(key => cache.delete(key)));
+      // Bump the counter; periodically run a real eviction sweep
+      const count = (_tileInsertCounters.get(cacheName) || 0) + 1;
+      _tileInsertCounters.set(cacheName, count);
+
+      if (count % EVICTION_CHECK_INTERVAL === 0) {
+        // Reset the counter — next sweep is another EVICTION_CHECK_INTERVAL away
+        _tileInsertCounters.set(cacheName, 0);
+        await maybeEvict(cache, cacheName);
      }
-      
-      cache.put(request, response.clone());
+
+      // Don't await put() — it can run after we return the response, keeping
+      // the fetch hot path lightweight.
+      cache.put(request, response.clone()).catch((err) => {
+        // QuotaExceededError → run an immediate eviction sweep and retry once
+        if (err && err.name === 'QuotaExceededError') {
+          maybeEvict(cache, cacheName, /* force */ true).catch(() => {});
+        }
+      });
    }
-    
+
    return response;
  } catch (error) {
-    // For tiles, just fail silently - map will show blank tile
+    // Offline — let the map renderer show a blank tile
    return new Response('', { status: 408, statusText: 'Offline' });
  }
 }

+/**
+ * Run an eviction sweep on a cache, dropping the oldest 10 % of entries
+ * when over the per-cache limit. Heavy: only call periodically.
+ */
+async function maybeEvict(cache, cacheName, force = false) {
+  try {
+    const limit = TILE_LIMITS[cacheName] || 1500;
+    const keys = await cache.keys();
+    if (force || keys.length >= limit) {
+      const drop = Math.max(1, Math.ceil(limit * 0.1));
+      const toDelete = keys.slice(0, drop);
+      await Promise.all(toDelete.map((k) => cache.delete(k)));
+    }
+  } catch (err) {
+    console.warn('[SW] eviction sweep failed for', cacheName, err);
+  }
+}
+
 // ============================================================================
 // MESSAGE HANDLING
 // ============================================================================

 self.addEventListener('message', (event) => {
  const { type, payload } = event.data || {};
-  
+
  switch (type) {
    case 'SKIP_WAITING':
      self.skipWaiting();
      break;
-      
+
    case 'CACHE_MODULES':
      cacheModules(payload.modules);
      break;
-      
+
    case 'CLEAR_USER_CACHE':
      clearUserCaches();
      break;
-      
+
    case 'GET_CACHE_STATUS':
-      getCacheStatus().then(status => {
+      getCacheStatus().then((status) => {
        event.source.postMessage({ type: 'CACHE_STATUS', status });
      });
      break;
+
+    // ----- Tile-cache management (Phase 1 offline maps) -----
+    case 'GET_TILE_STATS':
+      getTileStats().then((stats) => {
+        event.source.postMessage({ type: 'TILE_STATS', stats });
+      });
+      break;
+
+    case 'CLEAR_TILE_CACHES':
+      clearTileCaches().then(() => {
+        event.source.postMessage({ type: 'TILE_CACHES_CLEARED' });
+      });
+      break;
  }
 });

+// ============================================================================
+// HELPER FUNCTIONS
+// ============================================================================
+
 /**
- * Cache specific modules on demand
+ * Cache specific modules on demand.
 */
 async function cacheModules(moduleNames) {
  const cache = await caches.open(MODULES_CACHE);
-  
+
  for (const moduleName of moduleNames) {
    try {
      const moduleAssets = [
@ -277,9 +419,8 @@ async function cacheModules(moduleNames) {
        `/modules/${moduleName}/index.css`,
        `/modules/${moduleName}/index.html`
      ];
-      
+
      await cache.addAll(moduleAssets.filter(async (url) => {
-        // Only cache assets that exist
        try {
          const response = await fetch(url, { method: 'HEAD' });
          return response.ok;
@ -287,7 +428,7 @@ async function cacheModules(moduleNames) {
          return false;
        }
      }));
-      
+
      console.log('[SW] Cached module:', moduleName);
    } catch (error) {
      console.warn('[SW] Failed to cache module:', moduleName, error);
@ -296,7 +437,8 @@ async function cacheModules(moduleNames) {
 }

 /**
- * Clear user-specific caches (call on logout)
+ * Clear user-specific caches (call on logout).
+ * Tile caches are NOT cleared here — those belong to the device, not the user.
 */
 async function clearUserCaches() {
  await caches.delete(API_CACHE);
@ -305,17 +447,90 @@ async function clearUserCaches() {
 }

 /**
- * Get cache status information
+ * Get summary status of all caches (count of entries in each).
 */
 async function getCacheStatus() {
  const cacheNames = await caches.keys();
  const status = {};
-  
+
  for (const name of cacheNames) {
    const cache = await caches.open(name);
    const keys = await cache.keys();
    status[name] = keys.length;
  }
-  
+
  return status;
 }
+
+/**
+ * Get per-provider tile cache statistics.
+ *
+ * Returns shape:
+ *   {
+ *     totals: { count, estBytes },
+ *     byProvider: [{ key, label, count, limit, estBytes }, ...]
+ *   }
+ *
+ * estBytes is an approximation (count × AVG_TILE_BYTES). For an exact size,
+ * the caller can use navigator.storage.estimate() on the page side.
+ *
+ * Result is cached for STATS_TTL_MS so rapid re-queries (e.g. multiple
+ * Settings opens) don't re-enumerate every cache.
+ */
+const STATS_TTL_MS = 10 * 1000;
+let _cachedStats = null;
+let _cachedStatsAt = 0;
+
+async function getTileStats({ force = false } = {}) {
+  const now = Date.now();
+  if (!force && _cachedStats && (now - _cachedStatsAt) < STATS_TTL_MS) {
+    return _cachedStats;
+  }
+
+  const byProvider = [];
+  let totalCount = 0;
+
+  for (const cacheName of ALL_TILE_CACHES) {
+    let count = 0;
+    if (await caches.has(cacheName)) {
+      const cache = await caches.open(cacheName);
+      // matchAll returns a smaller payload than keys() on Safari, but neither
+      // is free. Done at most once per STATS_TTL_MS thanks to the cache above.
+      const keys = await cache.keys();
+      count = keys.length;
+    }
+    byProvider.push({
+      key:      cacheName,
+      label:    TILE_CACHE_LABELS[cacheName] || cacheName,
+      count,
+      limit:    TILE_LIMITS[cacheName] || 0,
+      estBytes: count * AVG_TILE_BYTES,
+    });
+    totalCount += count;
+  }
+
+  _cachedStats = {
+    totals: {
+      count:    totalCount,
+      estBytes: totalCount * AVG_TILE_BYTES,
+    },
+    byProvider,
+  };
+  _cachedStatsAt = now;
+  return _cachedStats;
+}
+
+/**
+ * Delete every tile cache. Frees the device storage used by cached map tiles.
+ * Does not affect app-shell, modules, or API caches.
+ */
+async function clearTileCaches() {
+  const results = await Promise.all(
+    ALL_TILE_CACHES.map((name) => caches.delete(name))
+  );
+  // Reset counters and invalidate stats cache
+  _tileInsertCounters.clear();
+  _cachedStats = null;
+  _cachedStatsAt = 0;
+  console.log('[SW] Cleared tile caches:', ALL_TILE_CACHES.filter((_, i) => results[i]));
+}
--- a/sql/create_landuse_parcels.sql
+++ b/sql/create_landuse_parcels.sql
@ -0,0 +1,207 @@
+-- ============================================================================
+-- LUPMIS — Land Use Parcels schema
+-- ============================================================================
+-- Source: "LAND USE INFORMATION FOR LUPMIS" (LUSPA, February 2026, revised)
+-- Implements the parcel-attribute table defined by Stephen / LUSPA, with a
+-- PostGIS geometry column and the indices needed for typical access patterns
+-- (spatial queries, lookup by zone / district / locality, time filtering).
+--
+-- Conventions:
+--   • Identifiers are unquoted (lowercase) — PostgreSQL folds them to lower
+--     case anyway, and this avoids the need for double-quotes in queries.
+--   • Source column names are PascalCase / Mixed_Case in the spec; their
+--     mapping to snake_case is shown in COMMENT ON COLUMN.
+--   • Geometry is stored in EPSG:4326 (WGS 84) for portability with the
+--     remote API. The MultiPolygon type accommodates parcels with islands
+--     or multi-part shapes.
+--
+-- Run as a database superuser (or a role with CREATEEXTENSION privilege)
+-- in the target database.
+-- ============================================================================
+
+-- PostGIS is required for the geometry column and spatial index.
+CREATE EXTENSION IF NOT EXISTS postgis;
+
+-- Drop existing table for clean re-runs in dev. Comment out for production.
+-- DROP TABLE IF EXISTS public.landuse_parcels CASCADE;
+
+-- ---------------------------------------------------------------------------
+-- Table: public.landuse_parcels
+-- ---------------------------------------------------------------------------
+CREATE TABLE IF NOT EXISTS public.landuse_parcels (
+    id              BIGSERIAL    PRIMARY KEY,
+
+    -- Spec field 1: UPN — Unique Parcel Number (Integer, up to 10 digits).
+    -- 10-digit integers can exceed INTEGER's max (2,147,483,647), hence BIGINT.
+    upn             BIGINT       NOT NULL,
+
+    -- Spec field 2: Style — Colour Assign ID (Integer, 2 digits).
+    -- References the colour palette defined in the Revised Zoning Guidelines
+    -- and Planning Standards (2025). Optional FK to a lookup table.
+    style           SMALLINT,
+
+    -- Spec field 3: Landuse — Broad land use (Text, 50).
+    landuse         VARCHAR(50),
+
+    -- Spec field 4: Zone_Code — Zone acronym (Text, 5), e.g. "Re A".
+    zone_code       VARCHAR(5),
+
+    -- Spec field 5: Zone_Name — Zone name (Text, 50), e.g. "Residential Zone A".
+    zone_name       VARCHAR(50),
+
+    -- Spec field 6: Sector — Sector number of plan area (Text, 5).
+    sector          VARCHAR(5),
+
+    -- Spec field 7: Block — Block name within the sector (Text, 3).
+    block           VARCHAR(3),
+
+    -- Spec field 8: Parcel_No — Plot number for land registration (Text, 5).
+    parcel_no       VARCHAR(5),
+
+    -- Spec field 9: Prop_No — Property number for street addressing (Text, 5).
+    prop_no         VARCHAR(5),
+
+    -- Spec field 10: St_Name — Street name (Text, 18). From the Street Naming
+    -- and Property Addressing System (SNPAS).
+    st_name         VARCHAR(18),
+
+    -- Spec field 11: Prop_Add — Property address (Text, 25).
+    prop_add        VARCHAR(25),
+
+    -- Spec field 12: Fac_Name — Facility name (Text, 100).
+    fac_name        VARCHAR(100),
+
+    -- Spec field 13: Min_Height — Minimum building height in storeys (Integer, 3).
+    min_height      SMALLINT,
+
+    -- Spec field 14: Max_Height — Maximum building height in storeys (Integer, 3).
+    max_height      SMALLINT,
+
+    -- Spec field 15: Eff_Date — Effective approval date by the District SPC.
+    eff_date        DATE,
+
+    -- Spec field 16: LP_Name — Local plan name (Text, 100).
+    lp_name         VARCHAR(100),
+
+    -- Spec field 17: Locality — Community / area name (Text, 50).
+    locality        VARCHAR(50),
+
+    -- Spec field 18: MMDA — Metropolitan / Municipal / District Assembly
+    --                       abbreviation (Text, 10), e.g. "LADMA".
+    mmda            VARCHAR(10),
+
+    -- Spec field 19: Last_Update — Last update on a parcel (e.g. change of
+    -- use approved by SPC).
+    last_update     DATE,
+
+    -- Spec field 20: Remarks — Additional info (Text, 200).
+    remarks         VARCHAR(200),
+
+    -- ------------------------------------------------------------------
+    -- Geometry — parcel polygon in WGS 84 (EPSG:4326).
+    -- MultiPolygon allows parcels with islands or disjoint parts.
+    -- ------------------------------------------------------------------
+    geom            geometry(MultiPolygon, 4326),
+
+    -- ------------------------------------------------------------------
+    -- Audit columns (not in the spec, added for change tracking)
+    -- ------------------------------------------------------------------
+    created_at      TIMESTAMPTZ  NOT NULL DEFAULT NOW(),
+    updated_at      TIMESTAMPTZ  NOT NULL DEFAULT NOW(),
+
+    -- ------------------------------------------------------------------
+    -- Constraints
+    -- ------------------------------------------------------------------
+    CONSTRAINT uq_landuse_parcels_upn        UNIQUE (upn),
+    CONSTRAINT ck_landuse_parcels_style      CHECK (style       IS NULL OR style      >= 0),
+    CONSTRAINT ck_landuse_parcels_min_height CHECK (min_height  IS NULL OR min_height >= 0),
+    CONSTRAINT ck_landuse_parcels_max_height CHECK (max_height  IS NULL OR max_height >= 0),
+    CONSTRAINT ck_landuse_parcels_height_order
+        CHECK (min_height IS NULL OR max_height IS NULL OR min_height <= max_height)
+);
+
+-- ---------------------------------------------------------------------------
+-- Column comments — preserve the source-document descriptions
+-- ---------------------------------------------------------------------------
+COMMENT ON TABLE  public.landuse_parcels IS 'Land use parcels — LUSPA spec, February 2026 (revised).';
+
+COMMENT ON COLUMN public.landuse_parcels.upn         IS 'UPN — Unique Parcel Number (Integer, 10 digits).';
+COMMENT ON COLUMN public.landuse_parcels.style       IS 'Style — Colour Assign ID per Revised Zoning Guidelines (2025).';
+COMMENT ON COLUMN public.landuse_parcels.landuse     IS 'Broad land use, e.g. Residential, Commercial, Mixed.';
+COMMENT ON COLUMN public.landuse_parcels.zone_code   IS 'Zone code (acronym), e.g. Re A.';
+COMMENT ON COLUMN public.landuse_parcels.zone_name   IS 'Zone name, e.g. Residential Zone A.';
+COMMENT ON COLUMN public.landuse_parcels.sector      IS 'Sector number of the plan area.';
+COMMENT ON COLUMN public.landuse_parcels.block       IS 'Block name within the sector.';
+COMMENT ON COLUMN public.landuse_parcels.parcel_no   IS 'Plot number for land registration.';
+COMMENT ON COLUMN public.landuse_parcels.prop_no     IS 'Property number for street addressing.';
+COMMENT ON COLUMN public.landuse_parcels.st_name     IS 'Street name (max 18 characters, per SNPAS).';
+COMMENT ON COLUMN public.landuse_parcels.prop_add    IS 'Property address of parcel.';
+COMMENT ON COLUMN public.landuse_parcels.fac_name    IS 'Facility name of property.';
+COMMENT ON COLUMN public.landuse_parcels.min_height  IS 'Minimum building height (storeys).';
+COMMENT ON COLUMN public.landuse_parcels.max_height  IS 'Maximum building height (storeys).';
+COMMENT ON COLUMN public.landuse_parcels.eff_date    IS 'Effective approval date by the District Spatial Planning Committee.';
+COMMENT ON COLUMN public.landuse_parcels.lp_name     IS 'Local plan name.';
+COMMENT ON COLUMN public.landuse_parcels.locality    IS 'Name of community or area.';
+COMMENT ON COLUMN public.landuse_parcels.mmda        IS 'Metropolitan/Municipal/District Assembly abbreviation, e.g. LADMA.';
+COMMENT ON COLUMN public.landuse_parcels.last_update IS 'Last update on a parcel (e.g. change of use approved by SPC).';
+COMMENT ON COLUMN public.landuse_parcels.remarks     IS 'Additional information on the parcel.';
+COMMENT ON COLUMN public.landuse_parcels.geom        IS 'Parcel boundary geometry (MultiPolygon, EPSG:4326).';
+COMMENT ON COLUMN public.landuse_parcels.created_at  IS 'Row-creation timestamp (audit).';
+COMMENT ON COLUMN public.landuse_parcels.updated_at  IS 'Row last-modified timestamp (audit, maintained by trigger).';
+
+-- ---------------------------------------------------------------------------
+-- Indices
+-- ---------------------------------------------------------------------------
+
+-- Spatial index — required for any ST_Intersects / ST_Within / map-bbox query.
+CREATE INDEX IF NOT EXISTS idx_landuse_parcels_geom
+    ON public.landuse_parcels
+    USING GIST (geom);
+
+-- B-tree indices for common attribute lookups.
+-- (uq_landuse_parcels_upn already creates an implicit index on upn.)
+CREATE INDEX IF NOT EXISTS idx_landuse_parcels_zone_code
+    ON public.landuse_parcels (zone_code);
+
+CREATE INDEX IF NOT EXISTS idx_landuse_parcels_mmda
+    ON public.landuse_parcels (mmda);
+
+CREATE INDEX IF NOT EXISTS idx_landuse_parcels_locality
+    ON public.landuse_parcels (locality);
+
+CREATE INDEX IF NOT EXISTS idx_landuse_parcels_lp_name
+    ON public.landuse_parcels (lp_name);
+
+CREATE INDEX IF NOT EXISTS idx_landuse_parcels_eff_date
+    ON public.landuse_parcels (eff_date);
+
+CREATE INDEX IF NOT EXISTS idx_landuse_parcels_last_update
+    ON public.landuse_parcels (last_update);
+
+-- Composite index for the very common "find all parcels in MMDA X with zone Y" query.
+CREATE INDEX IF NOT EXISTS idx_landuse_parcels_mmda_zone
+    ON public.landuse_parcels (mmda, zone_code);
+
+-- ---------------------------------------------------------------------------
+-- Trigger — keep updated_at fresh on every UPDATE
+-- ---------------------------------------------------------------------------
+CREATE OR REPLACE FUNCTION public.fn_landuse_parcels_set_updated_at()
+RETURNS TRIGGER
+LANGUAGE plpgsql
+AS $$
+BEGIN
+    NEW.updated_at := NOW();
+    RETURN NEW;
+END;
+$$;
+
+DROP TRIGGER IF EXISTS trg_landuse_parcels_set_updated_at ON public.landuse_parcels;
+
+CREATE TRIGGER trg_landuse_parcels_set_updated_at
+BEFORE UPDATE ON public.landuse_parcels
+FOR EACH ROW
+EXECUTE FUNCTION public.fn_landuse_parcels_set_updated_at();
+
+-- ============================================================================
+-- End of script
+-- ============================================================================
--- a/src/components/MapTools.js
+++ b/src/components/MapTools.js
@ -18,6 +18,7 @@ import { LineString, Circle, Polygon } from 'ol/geom';
 import { getLength, getArea } from 'ol/sphere';
 import Feature from 'ol/Feature';
 import { unByKey } from 'ol/Observable';
+import { formatLength, formatArea, formatCircleExtent } from '../units.js';

 // ol-ext imports
 import EditBar from 'ol-ext/control/EditBar';
@ -116,40 +117,6 @@ export class MapTools {
    });
  }
  
-  /**
-   * Format length output
-   */
-  formatLength(length) {
-    if (length > 1000) {
-      return (Math.round(length / 1000 * 100) / 100) + ' km';
-    } else {
-      return (Math.round(length * 100) / 100) + ' m';
-    }
-  }
-  
-  /**
-   * Format area output
-   */
-  formatArea(area) {
-    if (area > 1000000) {
-      return (Math.round(area / 1000000 * 100) / 100) + ' km²';
-    } else {
-      return (Math.round(area * 100) / 100) + ' m²';
-    }
-  }
-  
-  /**
-   * Format circle extent (bounding box area)
-   */
-  formatCircleExtent(radius) {
-    const area = Math.PI * radius * radius;
-    if (area > 1000000) {
-      return (Math.round(area / 1000000 * 100) / 100) + ' km²';
-    } else {
-      return (Math.round(area * 100) / 100) + ' m²';
-    }
-  }
-  
  /**
   * Create measurement tooltip overlay
   */
@ -231,8 +198,8 @@ export class MapTools {
        
        if (geom instanceof Circle) {
          const radius = geom.getRadius();
-          const area = this.formatCircleExtent(radius);
-          const radiusFormatted = this.formatLength(radius);
+          const area = formatCircleExtent(radius);
+          const radiusFormatted = formatLength(radius);
          
          const output = `<strong>${radiusFormatted}</strong><br><small>${area}</small>`;
          
@ -311,7 +278,7 @@ export class MapTools {
      listener = sketch.getGeometry().on('change', (e) => {
        const geom = e.target;
        const length = getLength(geom);
-        const output = this.formatLength(length);
+        const output = formatLength(length);
        
        this.measureTooltipElement.innerHTML = output;
        this.measureTooltip.setPosition(geom.getLastCoordinate());
@ -364,7 +331,7 @@ export class MapTools {
      listener = sketch.getGeometry().on('change', (e) => {
        const geom = e.target;
        const area = getArea(geom);
-        const output = this.formatArea(area);
+        const output = formatArea(area);
        
        this.measureTooltipElement.innerHTML = output;
        this.measureTooltip.setPosition(geom.getInteriorPoint().getCoordinates());
@ -376,6 +343,10 @@ export class MapTools {
      const geom = feature.getGeometry();
      const area = getArea(geom);

+      // Tag so the double-click handler can identify it
+      feature.set('_layerType', 'measure_area');
+      feature.set('_area', area);
+
      this.measureTooltipElement.className = 'measure-tooltip measure-tooltip-static';
      this.measureTooltipElement = null;
      this.createMeasureTooltip();
--- a/src/components/MapView.js
+++ b/src/components/MapView.js
--- a/src/database.js
+++ b/src/database.js
@ -196,6 +196,17 @@ export async function initSchema() {
      )
    `;

+    // Create osm_roads table for caching the OSM road network
+    console.log('[Database] Creating osm_roads table...');
+    await sql`
+      CREATE TABLE IF NOT EXISTS osm_roads (
+        osm_id INTEGER PRIMARY KEY,
+        geometry_wkt TEXT,
+        properties TEXT,
+        fetched_at TEXT DEFAULT CURRENT_TIMESTAMP
+      )
+    `;
+
    // Create indexes
    await sql`CREATE INDEX IF NOT EXISTS idx_locations_category ON locations(category)`;
    await sql`CREATE INDEX IF NOT EXISTS idx_locations_synced ON locations(synced)`;
@ -541,17 +552,20 @@ export async function getLocalCollectorZones() {
 export async function saveParcels(parcels) {
  try {
    await sql`DELETE FROM parcels`;
+    let saved = 0;
    for (const p of parcels) {
-      const props = JSON.stringify(p);
-      // API field names may vary — try common WKT field names
-      const wkt = p.polygon || p.boundary || p.geom || p.wkt || '';
      const id = p.id || p.parcelid || p.parcel_id || null;
+      if (id == null) continue; // skip rows without a usable ID
+      const props = JSON.stringify(p);
+      // API field names: 'boundary' (WKT), 'polygon', 'geom', 'wkt'
+      const wkt = p.boundary || p.polygon || p.geom || p.wkt || '';
      await sql`
-        INSERT INTO parcels (id, geometry_wkt, properties, fetched_at)
+        INSERT OR REPLACE INTO parcels (id, geometry_wkt, properties, fetched_at)
        VALUES (${id}, ${wkt}, ${props}, CURRENT_TIMESTAMP)
      `;
+      saved++;
    }
-    console.log('[Database] ✓ Saved', parcels.length, 'parcels');
+    console.log('[Database] ✓ Saved', saved, 'parcels (from', parcels.length, 'rows,', parcels.length - saved, 'duplicates replaced)');
  } catch (error) {
    console.error('[Database] ✗ Failed to save parcels:', error);
    throw error;
@ -680,6 +694,62 @@ export async function getLocalBuildingFootprints() {
  }
 }

+/**
+ * Save OSM roads to the local SQLite table.
+ * Replaces all existing rows.
+ *
+ * @param {Array} roads - Array of road objects from the API
+ */
+export async function saveOSMRoads(roads) {
+  try {
+    if (roads.length > 0) {
+      const first = roads[0];
+      const types = {};
+      for (const [k, v] of Object.entries(first)) {
+        types[k] = v === null ? 'null' : typeof v;
+      }
+      console.log('[Database] First road field types:', types);
+    }
+
+    await sql`DELETE FROM osm_roads`;
+    for (const r of roads) {
+      const props = JSON.stringify(r);
+
+      // Geometry — may arrive as WKT string or GeoJSON object
+      let rawWkt = r.geom || r.geometry || r.wkt || r.road || r.line || '';
+      const wkt = typeof rawWkt === 'object' ? JSON.stringify(rawWkt) : String(rawWkt);
+
+      // osm_id must be a primitive — fall back to null if missing or malformed
+      let rawId = r.osm_id ?? r.osmid ?? r.id ?? null;
+      const osmId = (rawId !== null && typeof rawId === 'object') ? null : rawId;
+
+      await sql`
+        INSERT OR REPLACE INTO osm_roads (osm_id, geometry_wkt, properties, fetched_at)
+        VALUES (${osmId}, ${wkt}, ${props}, CURRENT_TIMESTAMP)
+      `;
+    }
+    console.log('[Database] ✓ Saved', roads.length, 'OSM roads');
+  } catch (error) {
+    console.error('[Database] ✗ Failed to save OSM roads:', error);
+    throw error;
+  }
+}
+
+/**
+ * Load all cached OSM roads from the local table.
+ * @returns {Promise<Array|null>} Array of road objects, or null if empty
+ */
+export async function getLocalOSMRoads() {
+  try {
+    const rows = await sql`SELECT properties FROM osm_roads ORDER BY osm_id`;
+    if (rows.length === 0) return null;
+    return rows.map(r => JSON.parse(r.properties));
+  } catch (error) {
+    console.error('[Database] ✗ Failed to read local OSM roads:', error);
+    return null;
+  }
+}
+
 // ============================================================================
 // Export / Import
 // ============================================================================
@ -769,6 +839,90 @@ export async function getDatabaseStatus() {
 }
 }

+// ============================================================================
+// Cached-Layer Management
+// ============================================================================
+
+/**
+ * Tables that hold data fetched from the server.
+ *
+ * Clearing these is safe — the corresponding loaders (loadParcels,
+ * loadBuildingFootprints, loadOSMRoads, loadCollectorZones, …) will re-fetch
+ * the data from the API on the next app start.
+ *
+ * NOT included: user-created tables (`locations`, `pending_changes`) — those
+ * hold local work that must not be auto-deleted.
+ */
+export const CACHED_LAYER_TABLES = Object.freeze([
+  'parcels',
+  'building_footprints',
+  'osm_roads',
+  'collector_zones',
+  'remote_data',
+]);
+
+/**
+ * Check whether a table name is in the cleared-layer allow-list.
+ * @param {string} tableName
+ * @returns {boolean}
+ */
+export function isCachedLayerTable(tableName) {
+  return CACHED_LAYER_TABLES.includes(tableName);
+}
+
+/**
+ * Delete all rows from a single cached-layer table.
+ * Rejects unknown table names so this can't be abused to drop user data.
+ *
+ * @param {string} tableName - One of CACHED_LAYER_TABLES
+ * @returns {Promise<number>} Number of rows that were in the table before deletion
+ */
+export async function clearTable(tableName) {
+  if (!isCachedLayerTable(tableName)) {
+    throw new Error(`Refusing to clear "${tableName}" — not a known cached-layer table`);
+  }
+
+  const before = await sql(`SELECT COUNT(*) AS n FROM "${tableName}"`);
+  const count = before[0]?.n ?? 0;
+
+  await sql(`DELETE FROM "${tableName}"`);
+  console.log(`[Database] ✓ Cleared "${tableName}" (${count} rows)`);
+  broadcastChange(tableName, 'CLEAR', null);
+  return count;
+}
+
+/**
+ * Clear every cached-layer table (whatever exists in this database).
+ * Tables that don't exist yet are skipped silently.
+ *
+ * @returns {Promise<{ table: string, count: number }[]>} per-table report
+ */
+export async function clearAllCachedLayers() {
+  const existing = await sql`
+    SELECT name FROM sqlite_master
+    WHERE type='table' AND name IN (
+      'parcels', 'building_footprints', 'osm_roads', 'collector_zones', 'remote_data'
+    )
+  `;
+  const existingNames = new Set(existing.map((r) => r.name));
+
+  const results = [];
+  for (const tableName of CACHED_LAYER_TABLES) {
+    if (!existingNames.has(tableName)) continue;
+    try {
+      const count = await clearTable(tableName);
+      results.push({ table: tableName, count });
+    } catch (err) {
+      console.error(`[Database] Failed to clear ${tableName}:`, err);
+      results.push({ table: tableName, count: 0, error: err.message });
+    }
+  }
+
+  const total = results.reduce((s, r) => s + r.count, 0);
+  console.log(`[Database] ✓ Cleared all cached layers: ${total} rows across ${results.length} tables`);
+  return results;
+}
+
 /**
 * Get a list of all tables with their row counts.
 * @returns {Promise<Array<{name: string, count: number}>>}
@ -890,6 +1044,12 @@ export default {
  insertNewParcel,
  saveBuildingFootprints,
  getLocalBuildingFootprints,
+  saveOSMRoads,
+  getLocalOSMRoads,
+  CACHED_LAYER_TABLES,
+  isCachedLayerTable,
+  clearTable,
+  clearAllCachedLayers,
  exportDatabase,
  exportToGeoJSON,
  importDatabase,
--- a/src/geom/polygonDivide.js
+++ b/src/geom/polygonDivide.js
@ -0,0 +1,295 @@
+/**
+ * Pure geometry functions for dividing a polygon into N equal-area pieces.
+ *
+ * No OpenLayers dependency — operates on raw coordinate arrays.
+ *
+ * The algorithm finds the polygon's longest edge, then places N-1 cutting
+ * lines perpendicular to that edge.  Each cutting-line position is found
+ * via binary search so that the piece it cuts off has exactly 1/N of the
+ * remaining area.  The actual cut is delegated to `splitPolygonByLine()`.
+ */
+
+import { splitPolygonByLine } from './polygonSplit.js';
+
+// ── Utility helpers (self-contained) ─────────────────────────────────────────
+
+function dist2(a, b) {
+  return (a[0] - b[0]) ** 2 + (a[1] - b[1]) ** 2;
+}
+
+/**
+ * Signed area of a ring (shoelace formula).
+ */
+function signedArea(ring) {
+  let area = 0;
+  for (let i = 0, n = ring.length; i < n - 1; i++) {
+    area += ring[i][0] * ring[i + 1][1] - ring[i + 1][0] * ring[i][1];
+  }
+  return area / 2;
+}
+
+/**
+ * Absolute polygon area, accounting for holes.
+ */
+function polygonArea(coords) {
+  let area = Math.abs(signedArea(coords[0]));
+  for (let i = 1; i < coords.length; i++) {
+    area -= Math.abs(signedArea(coords[i]));
+  }
+  return area;
+}
+
+/**
+ * Find the longest edge of a ring and return direction vectors.
+ *
+ * @param {number[][]} ring  Closed ring
+ * @returns {{ p0: number[], p1: number[], along: number[], perp: number[] }}
+ *   `along` = unit vector along the longest edge,
+ *   `perp`  = unit vector perpendicular to `along` (rotated 90° CCW)
+ */
+function longestEdge(ring) {
+  const n = ring.length - 1; // unique vertices
+  let bestLen = -1;
+  let bestI = 0;
+
+  for (let i = 0; i < n; i++) {
+    const d = dist2(ring[i], ring[i + 1]);
+    if (d > bestLen) {
+      bestLen = d;
+      bestI = i;
+    }
+  }
+
+  const p0 = ring[bestI];
+  const p1 = ring[bestI + 1];
+  const len = Math.sqrt(bestLen);
+  const along = [(p1[0] - p0[0]) / len, (p1[1] - p0[1]) / len];
+  // Perpendicular: rotate 90° CCW
+  const perp = [-along[1], along[0]];
+
+  return { p0, p1, along, perp };
+}
+
+/**
+ * Build a cutting line perpendicular to `along` at parameter `t`.
+ *
+ * The line passes through `origin + t * along` and extends `extent` units
+ * in both `perp` directions — long enough to fully cross the polygon.
+ */
+function makeCuttingLine(origin, along, perp, t, extent) {
+  const cx = origin[0] + t * along[0];
+  const cy = origin[1] + t * along[1];
+  return [
+    [cx - extent * perp[0], cy - extent * perp[1]],
+    [cx + extent * perp[0], cy + extent * perp[1]],
+  ];
+}
+
+/**
+ * Project the centroid of a polygon's exterior ring onto the `along` axis.
+ * Returns the scalar parameter `t` relative to `origin`.
+ */
+function centroidT(coords, origin, along) {
+  const ring = coords[0];
+  const n = ring.length - 1;
+  let sx = 0, sy = 0;
+  for (let i = 0; i < n; i++) {
+    sx += ring[i][0];
+    sy += ring[i][1];
+  }
+  const cx = sx / n - origin[0];
+  const cy = sy / n - origin[1];
+  return cx * along[0] + cy * along[1];
+}
+
+// ── Main export ──────────────────────────────────────────────────────────────
+
+/**
+ * Divide a polygon into N equal-area pieces by parallel cuts perpendicular
+ * to a user-selected edge.
+ *
+ * @param {number[][][]} polygonCoords  Polygon coordinates [ring, ...holes]
+ * @param {number} n  Number of pieces (must be >= 1)
+ * @param {number[][]} edgeCoords  The selected edge `[p0, p1]` — cuts will be
+ *   perpendicular to this edge direction.
+ * @returns {{ pieces: number[][][][], error?: undefined } | { pieces: null, error: string }}
+ */
+export function dividePolygon(polygonCoords, n, edgeCoords) {
+  if (!Number.isInteger(n) || n < 1) {
+    return { pieces: null, error: 'Number of divisions must be a positive integer.' };
+  }
+  if (n === 1) {
+    return { pieces: [polygonCoords] };
+  }
+
+  const ring = polygonCoords[0];
+  const totalArea = polygonArea(polygonCoords);
+
+  if (totalArea < 1e-6) {
+    return { pieces: null, error: 'Polygon has no measurable area.' };
+  }
+
+  // 1. Determine cutting direction from the selected edge
+  let p0, along, perp;
+  if (edgeCoords && edgeCoords.length === 2) {
+    p0 = edgeCoords[0];
+    const dx = edgeCoords[1][0] - edgeCoords[0][0];
+    const dy = edgeCoords[1][1] - edgeCoords[0][1];
+    const len = Math.sqrt(dx * dx + dy * dy);
+    if (len < 1e-10) {
+      return { pieces: null, error: 'Selected edge has zero length.' };
+    }
+    along = [dx / len, dy / len];
+    perp = [-along[1], along[0]];
+  } else {
+    // Fallback: use longest edge
+    const edge = longestEdge(ring);
+    p0 = edge.p0;
+    along = edge.along;
+    perp = edge.perp;
+  }
+  const origin = p0;
+
+  // 2. Project all vertices onto the `along` axis to find extent
+  const nVerts = ring.length - 1;
+  let tMin = Infinity, tMax = -Infinity;
+  for (let i = 0; i < nVerts; i++) {
+    const dx = ring[i][0] - origin[0];
+    const dy = ring[i][1] - origin[1];
+    const t = dx * along[0] + dy * along[1];
+    if (t < tMin) tMin = t;
+    if (t > tMax) tMax = t;
+  }
+
+  // Cutting line extent: enough to cross the polygon in the `perp` direction
+  let perpMin = Infinity, perpMax = -Infinity;
+  for (let i = 0; i < nVerts; i++) {
+    const dx = ring[i][0] - origin[0];
+    const dy = ring[i][1] - origin[1];
+    const p = dx * perp[0] + dy * perp[1];
+    if (p < perpMin) perpMin = p;
+    if (p > perpMax) perpMax = p;
+  }
+  const extent = (perpMax - perpMin) * 1.5; // generous overshoot
+
+  // 3. Iteratively cut pieces
+  const pieces = [];
+  let remaining = polygonCoords;
+  let remainingCount = n;
+
+  for (let i = 0; i < n - 1; i++) {
+    const remainingArea = polygonArea(remaining);
+    const targetArea = remainingArea / remainingCount;
+
+    // Re-project the remaining polygon to get its current t-range
+    const remRing = remaining[0];
+    const remN = remRing.length - 1;
+    let rMin = Infinity, rMax = -Infinity;
+    for (let j = 0; j < remN; j++) {
+      const dx = remRing[j][0] - origin[0];
+      const dy = remRing[j][1] - origin[1];
+      const t = dx * along[0] + dy * along[1];
+      if (t < rMin) rMin = t;
+      if (t > rMax) rMax = t;
+    }
+
+    // Binary search for the cutting position
+    let lo = rMin;
+    let hi = rMax;
+    let bestT = (lo + hi) / 2;
+    let bestPiece = null;
+    let bestRemaining = null;
+    let bestError = Infinity;
+
+    for (let iter = 0; iter < 40; iter++) {
+      const mid = (lo + hi) / 2;
+      const line = makeCuttingLine(origin, along, perp, mid, extent);
+      const result = splitPolygonByLine(remaining, line);
+
+      if (!result) {
+        // Cutting line didn't produce a valid split — nudge and retry
+        // Try slightly shifted positions
+        const nudge = (hi - lo) * 0.01;
+        const lineA = makeCuttingLine(origin, along, perp, mid + nudge, extent);
+        const resultA = splitPolygonByLine(remaining, lineA);
+        if (resultA) {
+          const [halfA, halfB] = resultA;
+          const tA = centroidT(halfA, origin, along);
+          const tB = centroidT(halfB, origin, along);
+          const nearPiece = tA < tB ? halfA : halfB;
+          const farPiece = tA < tB ? halfB : halfA;
+          const nearArea = polygonArea(nearPiece);
+          const err = Math.abs(nearArea - targetArea);
+          if (err < bestError) {
+            bestError = err;
+            bestT = mid + nudge;
+            bestPiece = nearPiece;
+            bestRemaining = farPiece;
+          }
+        }
+        // Try the other direction
+        const lineB = makeCuttingLine(origin, along, perp, mid - nudge, extent);
+        const resultB = splitPolygonByLine(remaining, lineB);
+        if (resultB) {
+          const [halfA, halfB] = resultB;
+          const tA = centroidT(halfA, origin, along);
+          const tB = centroidT(halfB, origin, along);
+          const nearPiece = tA < tB ? halfA : halfB;
+          const farPiece = tA < tB ? halfB : halfA;
+          const nearArea = polygonArea(nearPiece);
+          const err = Math.abs(nearArea - targetArea);
+          if (err < bestError) {
+            bestError = err;
+            bestT = mid - nudge;
+            bestPiece = nearPiece;
+            bestRemaining = farPiece;
+          }
+        }
+        // Bisect anyway to keep converging
+        lo = mid;
+        continue;
+      }
+
+      const [halfA, halfB] = result;
+      const tA = centroidT(halfA, origin, along);
+      const tB = centroidT(halfB, origin, along);
+      const nearPiece = tA < tB ? halfA : halfB;
+      const farPiece = tA < tB ? halfB : halfA;
+      const nearArea = polygonArea(nearPiece);
+
+      const err = Math.abs(nearArea - targetArea);
+      if (err < bestError) {
+        bestError = err;
+        bestT = mid;
+        bestPiece = nearPiece;
+        bestRemaining = farPiece;
+      }
+
+      // Converged?
+      if (err / remainingArea < 0.001) break;
+
+      // Adjust search range
+      if (nearArea < targetArea) {
+        lo = mid; // need to cut farther out
+      } else {
+        hi = mid; // need to cut closer
+      }
+    }
+
+    if (!bestPiece || !bestRemaining) {
+      return {
+        pieces: null,
+        error: `Could not find a valid cut for piece ${i + 1} of ${n}. The polygon shape may be too irregular for equal division.`,
+      };
+    }
+
+    pieces.push(bestPiece);
+    remaining = bestRemaining;
+    remainingCount--;
+  }
+
+  // The last remaining piece is the Nth piece
+  pieces.push(remaining);
+
+  return { pieces };
+}
--- a/src/geom/polygonMerge.js
+++ b/src/geom/polygonMerge.js
@ -0,0 +1,407 @@
+/**
+ * Pure geometry functions for merging two adjacent polygons.
+ *
+ * No OpenLayers dependency — operates on raw coordinate arrays.
+ */
+
+/**
+ * Squared distance between two points.
+ */
+function dist2(a, b) {
+  return (a[0] - b[0]) ** 2 + (a[1] - b[1]) ** 2;
+}
+
+/**
+ * Signed area of a ring (shoelace formula).
+ * Positive = counter-clockwise, negative = clockwise.
+ */
+function signedArea(ring) {
+  let area = 0;
+  for (let i = 0, n = ring.length; i < n - 1; i++) {
+    area += (ring[i][0] * ring[i + 1][1]) - (ring[i + 1][0] * ring[i][1]);
+  }
+  return area / 2;
+}
+
+/**
+ * Test whether a point is inside a ring (ray-casting algorithm).
+ */
+function pointInRing(pt, ring) {
+  let inside = false;
+  for (let i = 0, j = ring.length - 2; i < ring.length - 1; j = i++) {
+    const xi = ring[i][0], yi = ring[i][1];
+    const xj = ring[j][0], yj = ring[j][1];
+    if (((yi > pt[1]) !== (yj > pt[1])) &&
+        (pt[0] < (xj - xi) * (pt[1] - yi) / (yj - yi) + xi)) {
+      inside = !inside;
+    }
+  }
+  return inside;
+}
+
+/**
+ * Ensure a ring has the desired winding order.
+ */
+function ensureWinding(ring, ccw) {
+  const area = signedArea(ring);
+  if ((ccw && area < 0) || (!ccw && area > 0)) {
+    return ring.slice().reverse();
+  }
+  return ring;
+}
+
+/**
+ * Close a ring (ensure first === last).
+ */
+function closeRing(coords) {
+  if (coords.length < 2) return coords;
+  if (dist2(coords[0], coords[coords.length - 1]) > 1e-10) {
+    return [...coords, coords[0].slice()];
+  }
+  return coords;
+}
+
+/**
+ * Perpendicular distance from a point to a segment.
+ *
+ * @param {number[]} pt
+ * @param {number[]} segA  Segment start
+ * @param {number[]} segB  Segment end
+ * @returns {number}  Squared distance
+ */
+function distToSegmentSq(pt, segA, segB) {
+  const dx = segB[0] - segA[0];
+  const dy = segB[1] - segA[1];
+  const lenSq = dx * dx + dy * dy;
+
+  if (lenSq < 1e-20) return dist2(pt, segA); // degenerate segment
+
+  // Parametric position of the projection
+  let t = ((pt[0] - segA[0]) * dx + (pt[1] - segA[1]) * dy) / lenSq;
+  t = Math.max(0, Math.min(1, t));
+
+  const projX = segA[0] + t * dx;
+  const projY = segA[1] + t * dy;
+  return (pt[0] - projX) ** 2 + (pt[1] - projY) ** 2;
+}
+
+/**
+ * Find the ring edge closest to a click coordinate.
+ *
+ * @param {number[][]} ring  Closed ring
+ * @param {number[]} clickCoord  [x, y]
+ * @returns {{ segIdx: number, distSq: number }}
+ */
+function findClosestEdge(ring, clickCoord) {
+  let bestIdx = 0;
+  let bestDist = Infinity;
+  const n = ring.length - 1; // unique vertices
+
+  for (let i = 0; i < n; i++) {
+    const d = distToSegmentSq(clickCoord, ring[i], ring[(i + 1) % n === 0 ? n : i + 1]);
+    if (d < bestDist) {
+      bestDist = d;
+      bestIdx = i;
+    }
+  }
+  return { segIdx: bestIdx, distSq: bestDist };
+}
+
+/**
+ * Check if two coordinates are equal within tolerance.
+ */
+function coordsEqual(a, b, tolSq) {
+  return dist2(a, b) < tolSq;
+}
+
+/**
+ * Test whether a point lies within tolerance of any edge of a ring.
+ *
+ * Unlike coordsEqual (vertex-to-vertex), this checks whether the point is
+ * close to the ring's *boundary* — it projects onto segments, so it works
+ * even when the two polygons have different vertex density along the shared
+ * edge or when vertices are slightly offset from separate digitisation.
+ *
+ * @param {number[]} pt         Point to test
+ * @param {number[][]} ring     Closed ring
+ * @param {number} tolSq        Squared distance tolerance
+ * @returns {boolean}
+ */
+function isVertexNearRing(pt, ring, tolSq) {
+  const n = ring.length - 1;
+  for (let i = 0; i < n; i++) {
+    if (distToSegmentSq(pt, ring[i], ring[i + 1]) < tolSq) {
+      return true;
+    }
+  }
+  return false;
+}
+
+/**
+ * Find the shared boundary between two polygon rings.
+ *
+ * Adjacent polygons share edges in reverse winding direction:
+ * if A walks P→Q along the shared boundary, B walks Q→P.
+ *
+ * The algorithm has two stages:
+ *
+ *   1. **Seed validation** — uses `isVertexNearRing` (vertex-to-edge proximity)
+ *      to confirm the user-clicked edges actually lie on a common boundary.
+ *      This is the forgiving check that handles offset vertices from separate
+ *      digitisation.
+ *
+ *   2. **Lockstep extension** — walks both rings together (A forward, B in
+ *      the opposite direction) and extends the shared boundary one vertex at
+ *      a time.  Three cases are tried at each step:
+ *        a) Both rings advance: vertex-to-vertex match (classic case).
+ *        b) Only A advances: A has an extra vertex that projects onto B's
+ *           frontier edge (different vertex density).
+ *        c) Only B advances: vice-versa.
+ *      Because extension is coupled to the *frontier edge* of the other ring
+ *      (not the entire ring), it cannot overshoot into non-shared territory,
+ *      even for small or closely-spaced polygons.
+ *
+ * @param {number[][]} ringA  Closed ring
+ * @param {number[][]} ringB  Closed ring
+ * @param {number} seedIdxA  Seed edge index on ring A
+ * @param {number} seedIdxB  Seed edge index on ring B
+ * @param {number} tolerance  Distance tolerance (in map units)
+ * @returns {{ startA: number, endA: number, startB: number, endB: number, reversed: boolean } | null}
+ */
+function findSharedBoundary(ringA, ringB, seedIdxA, seedIdxB, tolerance) {
+  const nA = ringA.length - 1; // unique vertices
+  const nB = ringB.length - 1;
+  const tolSq = tolerance * tolerance;
+
+  // ── Validate seed edges ─────────────────────────────────────────────
+  // Both vertices of the seed edge on A must be near ring B's boundary,
+  // or both vertices of the seed edge on B must be near ring A's boundary.
+  // This uses vertex-to-edge proximity so it handles offset digitisation.
+  const a0 = ringA[seedIdxA];
+  const a1 = ringA[(seedIdxA + 1) % nA];
+  const b0 = ringB[seedIdxB];
+  const b1 = ringB[(seedIdxB + 1) % nB];
+
+  const a0NearB = isVertexNearRing(a0, ringB, tolSq);
+  const a1NearB = isVertexNearRing(a1, ringB, tolSq);
+  const b0NearA = isVertexNearRing(b0, ringA, tolSq);
+  const b1NearA = isVertexNearRing(b1, ringA, tolSq);
+
+  if (!(a0NearB && a1NearB) && !(b0NearA && b1NearA)) {
+    console.warn('[polygonMerge] Seed edges are not on the shared boundary');
+    return null;
+  }
+
+  // ── Determine winding direction ─────────────────────────────────────
+  // Reversed (the normal case): A's a0 ≈ B's b1 and A's a1 ≈ B's b0.
+  let reversed;
+  if (coordsEqual(a0, b1, tolSq) && coordsEqual(a1, b0, tolSq)) {
+    reversed = true;
+  } else if (coordsEqual(a0, b0, tolSq) && coordsEqual(a1, b1, tolSq)) {
+    reversed = false;
+  } else {
+    // Vertices don't match exactly — use proximity to decide direction
+    reversed = dist2(a0, b1) < dist2(a0, b0);
+  }
+
+  // ── Initialise shared boundary ──────────────────────────────────────
+  let startA = seedIdxA;
+  let endA = (seedIdxA + 1) % nA;
+  let startB, endB;
+
+  if (reversed) {
+    // A walks startA → endA, B walks startB ← endB (reversed ring order)
+    startB = (seedIdxB + 1) % nB;
+    endB = seedIdxB;
+  } else {
+    startB = seedIdxB;
+    endB = (seedIdxB + 1) % nB;
+  }
+
+  // ── Extend forward (endA++, endB-- if reversed) ─────────────────────
+  // Walk both rings in lockstep.  At each step try three strategies:
+  //   1. Both advance — vertices match (vertex-to-vertex).
+  //   2. Only A advances — A's next vertex projects onto B's frontier edge.
+  //   3. Only B advances — B's next vertex projects onto A's frontier edge.
+  let safety = nA + nB;
+  while (safety-- > 0) {
+    const nextA = (endA + 1) % nA;
+    const nextB = reversed ? (endB - 1 + nB) % nB : (endB + 1) % nB;
+    if (nextA === startA || nextB === startB) break; // wrapped around
+
+    // Case 1: vertex-to-vertex match
+    if (coordsEqual(ringA[nextA], ringB[nextB], tolSq)) {
+      endA = nextA;
+      endB = nextB;
+      continue;
+    }
+
+    // Case 2: A has extra vertex — project onto B's frontier edge
+    if (distToSegmentSq(ringA[nextA], ringB[endB], ringB[nextB]) < tolSq) {
+      endA = nextA;
+      continue;
+    }
+
+    // Case 3: B has extra vertex — project onto A's frontier edge
+    if (distToSegmentSq(ringB[nextB], ringA[endA], ringA[nextA]) < tolSq) {
+      endB = nextB;
+      continue;
+    }
+
+    break; // no match — end of shared boundary
+  }
+
+  // ── Extend backward (startA--, startB++ if reversed) ────────────────
+  safety = nA + nB;
+  while (safety-- > 0) {
+    const prevA = (startA - 1 + nA) % nA;
+    const prevB = reversed ? (startB + 1) % nB : (startB - 1 + nB) % nB;
+    if (prevA === endA || prevB === endB) break;
+
+    // Case 1: vertex-to-vertex match
+    if (coordsEqual(ringA[prevA], ringB[prevB], tolSq)) {
+      startA = prevA;
+      startB = prevB;
+      continue;
+    }
+
+    // Case 2: A has extra vertex — project onto B's frontier edge
+    if (distToSegmentSq(ringA[prevA], ringB[startB], ringB[prevB]) < tolSq) {
+      startA = prevA;
+      continue;
+    }
+
+    // Case 3: B has extra vertex — project onto A's frontier edge
+    if (distToSegmentSq(ringB[prevB], ringA[startA], ringA[prevA]) < tolSq) {
+      startB = prevB;
+      continue;
+    }
+
+    break;
+  }
+
+  return { startA, endA, startB, endB, reversed };
+}
+
+/**
+ * Walk a ring from startIdx to endIdx (exclusive), going forward and wrapping.
+ * Skips startIdx and stops before reaching endIdx.
+ * Returns the vertices of the non-shared portion.
+ *
+ * @param {number[][]} ring  Closed ring
+ * @param {number} fromIdx  Start walking from this index (inclusive)
+ * @param {number} toIdx    Stop at this index (inclusive)
+ * @returns {number[][]}
+ */
+function walkRing(ring, fromIdx, toIdx) {
+  const n = ring.length - 1;
+  const result = [];
+  let idx = fromIdx;
+  while (true) {
+    result.push(ring[idx]);
+    if (idx === toIdx) break;
+    idx = (idx + 1) % n;
+    // Safety: prevent infinite loops
+    if (result.length > n + 1) break;
+  }
+  return result;
+}
+
+/**
+ * Merge two adjacent polygons along their shared boundary.
+ *
+ * @param {number[][][]} polygonCoordsA  Polygon A coordinates [exteriorRing, ...holes]
+ * @param {number[][][]} polygonCoordsB  Polygon B coordinates [exteriorRing, ...holes]
+ * @param {number[]} clickCoordA  Click coordinate on the shared edge of polygon A
+ * @param {number[]} clickCoordB  Click coordinate on the shared edge of polygon B
+ * @param {number} [tolerance=5]  Distance tolerance in map units (default 5 metres in EPSG:3857).
+ *   A larger tolerance handles polygons that were digitised separately and
+ *   whose shared vertices don't coincide exactly.
+ * @returns {{ coords: number[][][], error?: undefined } | { coords: null, error: string }}
+ *   On success: `{ coords: [...] }`.  On failure: `{ coords: null, error: 'reason' }`.
+ */
+export function mergePolygons(polygonCoordsA, polygonCoordsB, clickCoordA, clickCoordB, tolerance = 5) {
+  const ringA = polygonCoordsA[0];
+  const ringB = polygonCoordsB[0];
+  const holesA = polygonCoordsA.slice(1);
+  const holesB = polygonCoordsB.slice(1);
+
+  // 1. Find seed edges (closest to user clicks)
+  const seedA = findClosestEdge(ringA, clickCoordA);
+  const seedB = findClosestEdge(ringB, clickCoordB);
+
+  // 2. Find shared boundary
+  const shared = findSharedBoundary(ringA, ringB, seedA.segIdx, seedB.segIdx, tolerance);
+  if (!shared) {
+    console.warn('[polygonMerge] Could not find shared boundary between polygons — seed edges are not near the other ring');
+    return { coords: null, error: 'The selected edges are not on a shared boundary. Click edges that lie on the common border between the two polygons.' };
+  }
+
+  const { startA, endA, startB, endB, reversed } = shared;
+  const nA = ringA.length - 1;
+  const nB = ringB.length - 1;
+
+  // 3. Stitch the non-shared portions together
+  //    A's shared goes from startA → endA.  Non-shared: endA → startA (forward, wrapping).
+  //    B's shared (reversed case) goes from startB backward to endB.
+  //      Non-shared: startB → endB (forward).
+  //    B's shared (same-dir case) goes from startB → endB.
+  //      Non-shared: endB → startB (forward, wrapping).
+  //
+  //    The last vertex of partA (startA) must coincide with the first vertex
+  //    of partB for a clean join.
+
+  const partA = walkRing(ringA, endA, startA);
+
+  let partB;
+  if (reversed) {
+    // B's non-shared goes from startB forward to endB.
+    // startB vertex ≈ startA vertex (they meet at one end of the shared boundary).
+    partB = walkRing(ringB, startB, endB);
+  } else {
+    // B's non-shared goes from endB forward to startB.
+    partB = walkRing(ringB, endB, startB);
+  }
+
+  // partA ends at startA, partB starts at a vertex that should coincide.
+  // Skip the first vertex of partB to avoid the duplicate junction point.
+  const merged = [...partA, ...partB.slice(1)];
+
+  // Snap the closing junction.  With non-coincident vertices (separate
+  // digitisation) the last vertex of partB may be a few metres from the
+  // first vertex of partA (ringA[endA]).  Replace it to avoid a tiny
+  // sliver edge that closeRing would otherwise create.
+  const tolSq = tolerance * tolerance;
+  if (merged.length > 2 && dist2(merged[merged.length - 1], merged[0]) < tolSq) {
+    merged[merged.length - 1] = merged[0].slice();
+  }
+
+  const mergedRing = closeRing(merged);
+
+  // 4. Validate: the merged ring should have a reasonable area
+  const areaA = Math.abs(signedArea(ringA));
+  const areaB = Math.abs(signedArea(ringB));
+  const areaMerged = Math.abs(signedArea(mergedRing));
+  const expectedArea = areaA + areaB;
+
+  // Allow 10% tolerance for area mismatch (shared edges can cause slight differences)
+  if (areaMerged < expectedArea * 0.5 || areaMerged > expectedArea * 1.5) {
+    console.warn(`[polygonMerge] Area mismatch: A=${areaA.toFixed(1)}, B=${areaB.toFixed(1)}, merged=${areaMerged.toFixed(1)}, expected≈${expectedArea.toFixed(1)}`);
+    return { coords: null, error: 'Merge produced an invalid polygon (area mismatch). The polygons may not be truly adjacent — try clicking closer to the shared boundary.' };
+  }
+
+  // 5. Match winding order to original
+  const originalCCW = signedArea(ringA) > 0;
+  const finalRing = ensureWinding(mergedRing, originalCCW);
+
+  // 6. Collect holes from both polygons
+  const allHoles = [...holesA, ...holesB];
+  // Filter: only include holes that actually fall inside the merged ring
+  const validHoles = allHoles.filter(hole => {
+    const cx = hole.reduce((s, p) => s + p[0], 0) / (hole.length - 1);
+    const cy = hole.reduce((s, p) => s + p[1], 0) / (hole.length - 1);
+    return pointInRing([cx, cy], finalRing);
+  });
+
+  return { coords: [finalRing, ...validHoles] };
+}
--- a/src/geom/polygonSplit.js
+++ b/src/geom/polygonSplit.js
@ -0,0 +1,395 @@
+/**
+ * Pure geometry functions for splitting a polygon by a line.
+ *
+ * No OpenLayers dependency — operates on raw coordinate arrays.
+ */
+
+/**
+ * Compute the intersection point of two 2D line segments.
+ * Segment A: p1→p2, Segment B: p3→p4.
+ *
+ * @param {number[]} p1
+ * @param {number[]} p2
+ * @param {number[]} p3
+ * @param {number[]} p4
+ * @param {number} [eps=1e-10] tolerance for parallel check
+ * @returns {{ point: number[], t: number, u: number } | null}
+ *   t = parametric position on segment A (0–1),
+ *   u = parametric position on segment B (0–1)
+ */
+function segmentIntersection(p1, p2, p3, p4, eps = 1e-10) {
+  const dx1 = p2[0] - p1[0];
+  const dy1 = p2[1] - p1[1];
+  const dx2 = p4[0] - p3[0];
+  const dy2 = p4[1] - p3[1];
+
+  const denom = dx1 * dy2 - dy1 * dx2;
+  if (Math.abs(denom) < eps) return null; // parallel / collinear
+
+  const dx3 = p3[0] - p1[0];
+  const dy3 = p3[1] - p1[1];
+
+  const t = (dx3 * dy2 - dy3 * dx2) / denom;
+  const u = (dx3 * dy1 - dy3 * dx1) / denom;
+
+  if (t < -eps || t > 1 + eps || u < -eps || u > 1 + eps) return null;
+
+  return {
+    point: [p1[0] + t * dx1, p1[1] + t * dy1],
+    t: Math.max(0, Math.min(1, t)),
+    u: Math.max(0, Math.min(1, u)),
+  };
+}
+
+/**
+ * Signed area of a ring (shoelace formula).
+ * Positive = counter-clockwise, negative = clockwise.
+ */
+function signedArea(ring) {
+  let area = 0;
+  for (let i = 0, n = ring.length; i < n - 1; i++) {
+    area += (ring[i][0] * ring[i + 1][1]) - (ring[i + 1][0] * ring[i][1]);
+  }
+  return area / 2;
+}
+
+/**
+ * Test whether a point is inside a ring (ray-casting algorithm).
+ */
+function pointInRing(pt, ring) {
+  let inside = false;
+  for (let i = 0, j = ring.length - 2; i < ring.length - 1; j = i++) {
+    const xi = ring[i][0], yi = ring[i][1];
+    const xj = ring[j][0], yj = ring[j][1];
+    if (((yi > pt[1]) !== (yj > pt[1])) &&
+        (pt[0] < (xj - xi) * (pt[1] - yi) / (yj - yi) + xi)) {
+      inside = !inside;
+    }
+  }
+  return inside;
+}
+
+/**
+ * Squared distance between two points.
+ */
+function dist2(a, b) {
+  return (a[0] - b[0]) ** 2 + (a[1] - b[1]) ** 2;
+}
+
+/**
+ * Find all intersection points between a cutting line and a polygon ring.
+ *
+ * @param {number[][]} ring  Closed ring coordinates (first === last)
+ * @param {number[][]} line  LineString coordinates (2+ points)
+ * @returns {Array<{ point: number[], ringSegIdx: number, ringT: number, lineSegIdx: number, lineT: number }>}
+ */
+function findIntersections(ring, line) {
+  const hits = [];
+  const eps = 1e-10;
+
+  for (let li = 0; li < line.length - 1; li++) {
+    for (let ri = 0; ri < ring.length - 1; ri++) {
+      const ix = segmentIntersection(ring[ri], ring[ri + 1], line[li], line[li + 1], eps);
+      if (!ix) continue;
+
+      // Skip if intersection is at the very start of the ring segment
+      // but was already caught as the end of the previous segment
+      const pt = ix.point;
+
+      // Avoid duplicate hits at shared vertices
+      let isDup = false;
+      for (const h of hits) {
+        if (dist2(h.point, pt) < 1e-6) {
+          isDup = true;
+          break;
+        }
+      }
+      if (isDup) continue;
+
+      hits.push({
+        point: pt,
+        ringSegIdx: ri,
+        ringT: ix.t,
+        lineSegIdx: li,
+        lineT: ix.u,
+      });
+    }
+  }
+
+  // Sort by position along the cutting line
+  hits.sort((a, b) => {
+    if (a.lineSegIdx !== b.lineSegIdx) return a.lineSegIdx - b.lineSegIdx;
+    return a.lineT - b.lineT;
+  });
+
+  return hits;
+}
+
+/**
+ * Insert intersection points into a ring, returning the expanded ring
+ * and the new indices of the inserted points.
+ *
+ * @param {number[][]} ring  Closed ring (first === last)
+ * @param {Array<{ point: number[], ringSegIdx: number, ringT: number }>} hits
+ *   Sorted by ringSegIdx then ringT.
+ * @returns {{ ring: number[][], indices: number[] }}
+ */
+function insertPointsIntoRing(ring, hits) {
+  // Sort hits by ring position (segment index, then parametric t) so
+  // we can insert from back to front without shifting earlier indices.
+  const sorted = hits.map((h, i) => ({ ...h, origOrder: i }));
+  sorted.sort((a, b) => {
+    if (a.ringSegIdx !== b.ringSegIdx) return a.ringSegIdx - b.ringSegIdx;
+    return a.ringT - b.ringT;
+  });
+
+  const expanded = ring.slice(); // copy
+  const indices = new Array(sorted.length);
+
+  // Insert from the end so that earlier insertions don't shift later indices.
+  for (let k = sorted.length - 1; k >= 0; k--) {
+    const h = sorted[k];
+    const insertIdx = h.ringSegIdx + 1;
+
+    // Check if this point is essentially identical to an existing vertex
+    const snapDist = 1e-6;
+    if (dist2(h.point, expanded[h.ringSegIdx]) < snapDist) {
+      indices[h.origOrder] = h.ringSegIdx;
+      continue;
+    }
+    if (dist2(h.point, expanded[h.ringSegIdx + 1]) < snapDist) {
+      indices[h.origOrder] = h.ringSegIdx + 1;
+      continue;
+    }
+
+    // Insert the new point
+    expanded.splice(insertIdx, 0, h.point);
+    indices[h.origOrder] = insertIdx;
+
+    // Adjust indices for all previously recorded insertions
+    // that reference a position >= insertIdx
+    for (let j = k + 1; j < sorted.length; j++) {
+      if (indices[sorted[j].origOrder] >= insertIdx) {
+        indices[sorted[j].origOrder]++;
+      }
+    }
+  }
+
+  return { ring: expanded, indices };
+}
+
+/**
+ * Extract a slice of a ring from index i0 to i1 (going forward, wrapping).
+ * Both endpoints are included.
+ *
+ * @param {number[][]} ring  Closed ring (first === last); length includes closing vertex
+ * @param {number} i0  Start index (inclusive)
+ * @param {number} i1  End index (inclusive)
+ * @returns {number[][]}
+ */
+function ringSlice(ring, i0, i1) {
+  const n = ring.length - 1; // number of unique vertices (ring is closed)
+  // Normalise indices into the [0, n-1] range
+  const start = ((i0 % n) + n) % n;
+  const end = ((i1 % n) + n) % n;
+  const result = [];
+  let idx = start;
+  while (true) {
+    result.push(ring[idx]);
+    if (idx === end) break;
+    idx = (idx + 1) % n;
+  }
+  return result;
+}
+
+/**
+ * Extract the cutting line segment between two intersection points.
+ *
+ * @param {number[][]} line       Full cutting line coordinates
+ * @param {{ point: number[], lineSegIdx: number, lineT: number }} hit0
+ * @param {{ point: number[], lineSegIdx: number, lineT: number }} hit1
+ * @returns {number[][]}  Coordinates from hit0.point to hit1.point along the line
+ */
+function cuttingLineSlice(line, hit0, hit1) {
+  const result = [hit0.point];
+
+  // Include all intermediate line vertices between the two hit segments
+  const startSeg = hit0.lineSegIdx;
+  const endSeg = hit1.lineSegIdx;
+
+  for (let i = startSeg + 1; i <= endSeg; i++) {
+    result.push(line[i]);
+  }
+
+  // Add the end intersection point if it's not the same as the last vertex
+  if (dist2(result[result.length - 1], hit1.point) > 1e-10) {
+    result.push(hit1.point);
+  }
+
+  return result;
+}
+
+/**
+ * Ensure a ring has the desired winding order.
+ * @param {number[][]} ring  Closed ring
+ * @param {boolean} ccw  true for counter-clockwise
+ * @returns {number[][]}
+ */
+function ensureWinding(ring, ccw) {
+  const area = signedArea(ring);
+  if ((ccw && area < 0) || (!ccw && area > 0)) {
+    return ring.slice().reverse();
+  }
+  return ring;
+}
+
+/**
+ * Close a ring (ensure first === last).
+ */
+function closeRing(coords) {
+  if (coords.length < 2) return coords;
+  const first = coords[0];
+  const last = coords[coords.length - 1];
+  if (dist2(first, last) > 1e-10) {
+    return [...coords, first.slice()];
+  }
+  return coords;
+}
+
+/**
+ * Extend a cutting line so that both endpoints lie outside the polygon ring.
+ * If an endpoint is inside, we extend the first/last segment outward past the
+ * bounding box diagonal so it definitely exits.
+ *
+ * @param {number[][]} line  Cutting line coordinates
+ * @param {number[][]} ring  Closed polygon ring
+ * @returns {number[][]}  Extended line (may be the original if already outside)
+ */
+function extendLineOutsideRing(line, ring) {
+  // Compute bounding-box diagonal for a generous extension distance
+  let minX = Infinity, minY = Infinity, maxX = -Infinity, maxY = -Infinity;
+  for (const pt of ring) {
+    if (pt[0] < minX) minX = pt[0];
+    if (pt[1] < minY) minY = pt[1];
+    if (pt[0] > maxX) maxX = pt[0];
+    if (pt[1] > maxY) maxY = pt[1];
+  }
+  const diag = Math.sqrt((maxX - minX) ** 2 + (maxY - minY) ** 2) || 1;
+
+  const result = line.slice();
+
+  // Extend start if inside
+  if (pointInRing(result[0], ring)) {
+    const p0 = result[0];
+    const p1 = result[1];
+    const dx = p0[0] - p1[0];
+    const dy = p0[1] - p1[1];
+    const len = Math.sqrt(dx * dx + dy * dy) || 1;
+    const scale = diag * 2 / len;
+    result[0] = [p0[0] + dx * scale, p0[1] + dy * scale];
+  }
+
+  // Extend end if inside
+  const last = result.length - 1;
+  if (pointInRing(result[last], ring)) {
+    const pN = result[last];
+    const pN1 = result[last - 1];
+    const dx = pN[0] - pN1[0];
+    const dy = pN[1] - pN1[1];
+    const len = Math.sqrt(dx * dx + dy * dy) || 1;
+    const scale = diag * 2 / len;
+    result[last] = [pN[0] + dx * scale, pN[1] + dy * scale];
+  }
+
+  return result;
+}
+
+/**
+ * Split a polygon by a cutting line.
+ *
+ * The cutting line can start or end inside the polygon — the algorithm will
+ * automatically extend it outward so it crosses the boundary at exactly 2
+ * points.  Multi-vertex cutting lines (with corners or approximated arcs)
+ * are fully supported.
+ *
+ * @param {number[][][]} polygonCoords  Polygon coordinates:
+ *   [exteriorRing, ...holeRings] where each ring is closed (first === last)
+ * @param {number[][]} lineCoords  Cutting line coordinates (2+ points)
+ * @returns {number[][][][] | null}  Two polygon coordinate arrays, or null if split failed
+ */
+export function splitPolygonByLine(polygonCoords, lineCoords) {
+  const exteriorRing = polygonCoords[0];
+  const holes = polygonCoords.slice(1);
+
+  // Extend the cutting line if its endpoints are inside the polygon
+  const extendedLine = extendLineOutsideRing(lineCoords, exteriorRing);
+
+  // 1. Find intersections between cutting line and exterior ring
+  const hits = findIntersections(exteriorRing, extendedLine);
+
+  // We need exactly 2 intersection points for a simple split
+  if (hits.length !== 2) {
+    console.warn(`[polygonSplit] Expected 2 intersections, got ${hits.length}`);
+    return null;
+  }
+
+  const [hit0, hit1] = hits;
+
+  // 2. Insert intersection points into the ring
+  const { ring: expandedRing, indices } = insertPointsIntoRing(exteriorRing, hits);
+  const idx0 = indices[0];
+  const idx1 = indices[1];
+
+  // Ensure idx0 < idx1 for consistent traversal
+  const [iA, iB] = idx0 < idx1 ? [idx0, idx1] : [idx1, idx0];
+  const [hitA, hitB] = idx0 < idx1 ? [hit0, hit1] : [hit1, hit0];
+
+  // 3. Get the cutting line segment between the two intersection points
+  const cutForward = idx0 < idx1
+    ? cuttingLineSlice(extendedLine, hit0, hit1)
+    : cuttingLineSlice(extendedLine, hit1, hit0);
+  const cutReverse = cutForward.slice().reverse();
+
+  // 4. Build two polygon rings
+  //    Ring A: walk ring from iA to iB (forward), then cutting line reversed back to iA
+  const sliceAB = ringSlice(expandedRing, iA, iB);
+  const ringA = closeRing([...sliceAB, ...cutReverse.slice(1)]);
+
+  //    Ring B: walk ring from iB to iA (wrapping), then cutting line forward back to iB
+  const sliceBA = ringSlice(expandedRing, iB, iA);
+  const ringB = closeRing([...sliceBA, ...cutForward.slice(1)]);
+
+  // 5. Match winding order to original
+  const originalCCW = signedArea(exteriorRing) > 0;
+  const finalA = ensureWinding(ringA, originalCCW);
+  const finalB = ensureWinding(ringB, originalCCW);
+
+  // 6. Build polygon coordinate arrays, assigning holes to the correct piece
+  const polyA = [finalA];
+  const polyB = [finalB];
+
+  for (const hole of holes) {
+    // Use the centroid of the hole to determine containment
+    const centroid = holeCentroid(hole);
+    if (pointInRing(centroid, finalA)) {
+      polyA.push(hole);
+    } else {
+      polyB.push(hole);
+    }
+  }
+
+  return [polyA, polyB];
+}
+
+/**
+ * Compute the centroid of a closed ring.
+ */
+function holeCentroid(ring) {
+  let cx = 0, cy = 0;
+  const n = ring.length - 1; // exclude closing vertex
+  for (let i = 0; i < n; i++) {
+    cx += ring[i][0];
+    cy += ring[i][1];
+  }
+  return [cx / n, cy / n];
+}
--- a/src/interactions/PolygonDivideInteraction.js
+++ b/src/interactions/PolygonDivideInteraction.js
@ -0,0 +1,492 @@
+/**
+ * PolygonDivideInteraction
+ *
+ * A three-phase OpenLayers interaction for dividing a polygon into N
+ * equal-area pieces:
+ *   Phase 1 – SELECT: hover to highlight, click to select a polygon
+ *   Phase 2 – EDGE:   hover to highlight edges, click to pick the divide
+ *                      direction (cuts will be perpendicular to this edge)
+ *   Phase 3 – FORM:   wait for the popup form to call performDivide(n)
+ *
+ * After a successful divide the original feature is removed and N new
+ * coloured features are added.  The interaction fires `beforedivide` and
+ * `afterdivide` events compatible with ol-ext's UndoRedo.
+ */
+
+import ol_interaction_Interaction from 'ol/interaction/Interaction';
+import VectorSource from 'ol/source/Vector';
+import VectorLayer from 'ol/layer/Vector';
+import Feature from 'ol/Feature';
+import { Style, Stroke, Fill } from 'ol/style';
+import { LineString, Polygon as PolygonGeom } from 'ol/geom';
+import { dividePolygon } from '../geom/polygonDivide.js';
+import { showToast } from '../toast.js';
+
+// Highlight style for the selected polygon (phase 1)
+const HIGHLIGHT_STYLE = new Style({
+  stroke: new Stroke({ color: '#0ea5e9', width: 3 }),
+  fill: new Fill({ color: 'rgba(14,165,233,0.15)' }),
+});
+
+// Style for the hovered edge (phase 2)
+const EDGE_STYLE = new Style({
+  stroke: new Stroke({ color: '#8b5cf6', width: 4, lineDash: [10, 6] }),
+});
+
+/**
+ * Generate N visually distinct colours using evenly-spaced HSL hues.
+ */
+function pieceColors(n) {
+  const colors = [];
+  for (let i = 0; i < n; i++) {
+    const hue = Math.round((i * 360) / n);
+    colors.push({
+      stroke: `hsl(${hue}, 70%, 45%)`,
+      fill: `hsla(${hue}, 70%, 55%, 0.25)`,
+    });
+  }
+  return colors;
+}
+
+export class PolygonDivideInteraction extends ol_interaction_Interaction {
+  /**
+   * @param {Object} options
+   * @param {VectorSource|VectorSource[]} [options.sources]  Specific sources
+   *   to search.  If omitted the interaction searches all visible vector layers.
+   * @param {number} [options.snapDistance=25]  Pixel distance for hover.
+   */
+  constructor(options = {}) {
+    super({
+      handleEvent: (e) => this._handleEvent(e),
+    });
+
+    this.snapDistance_ = options.snapDistance || 25;
+    this._sources = options.sources
+      ? (Array.isArray(options.sources) ? options.sources : [options.sources])
+      : null;
+
+    // Phase: 'select' | 'edge' | 'form' | 'pick'
+    this._phase = 'select';
+    this._selectedFeature = null;
+    this._selectedSource = null;
+    this._selectedEdge = null; // [p0, p1] — the edge the user clicked
+    this._dividedFeatures = null; // features created after divide (for pick phase)
+
+    // Overlay layer for polygon highlight
+    this._overlaySource = new VectorSource({ useSpatialIndex: false });
+    this._overlayLayer = new VectorLayer({
+      source: this._overlaySource,
+      displayInLayerSwitcher: false,
+      style: HIGHLIGHT_STYLE,
+    });
+
+    // Overlay layer for edge highlight
+    this._edgeSource = new VectorSource({ useSpatialIndex: false });
+    this._edgeLayer = new VectorLayer({
+      source: this._edgeSource,
+      displayInLayerSwitcher: false,
+      style: EDGE_STYLE,
+    });
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Map lifecycle                                                      */
+  /* ------------------------------------------------------------------ */
+
+  setMap(map) {
+    if (this.getMap()) {
+      this.getMap().removeLayer(this._overlayLayer);
+      this.getMap().removeLayer(this._edgeLayer);
+    }
+    super.setMap(map);
+    if (map) {
+      this._overlayLayer.setMap(map);
+      this._edgeLayer.setMap(map);
+    }
+  }
+
+  setActive(active) {
+    super.setActive(active);
+    if (!active) {
+      this._reset();
+    }
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Source helpers                                                      */
+  /* ------------------------------------------------------------------ */
+
+  _getSources() {
+    if (this._sources) return this._sources;
+    if (!this.getMap()) return [];
+    const sources = [];
+    const collect = (layers) => {
+      layers.forEach((layer) => {
+        if (layer.getVisible()) {
+          if (layer.getSource && layer.getSource() instanceof VectorSource) {
+            sources.push(layer.getSource());
+          } else if (layer.getLayers) {
+            collect(layer.getLayers());
+          }
+        }
+      });
+    };
+    collect(this.getMap().getLayers());
+    return sources;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Event router                                                       */
+  /* ------------------------------------------------------------------ */
+
+  _handleEvent(e) {
+    if (!this.getActive()) return true;
+
+    // Escape cancels at any phase
+    if (e.type === 'keydown' && e.originalEvent?.key === 'Escape') {
+      if (this._phase === 'form') {
+        this.cancelDivide();
+      } else {
+        this._reset();
+      }
+      return false;
+    }
+
+    if (this._phase === 'select') {
+      if (e.type === 'pointermove') return this._onSelectMove(e);
+      if (e.type === 'singleclick') return this._onSelectClick(e);
+    }
+
+    if (this._phase === 'edge') {
+      if (e.type === 'pointermove') return this._onEdgeMove(e);
+      if (e.type === 'singleclick') return this._onEdgeClick(e);
+    }
+
+    if (this._phase === 'pick') {
+      if (e.type === 'pointermove') return this._onPickMove(e);
+      if (e.type === 'singleclick') return this._onPickClick(e);
+    }
+
+    return true;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Phase 1: SELECT polygon                                            */
+  /* ------------------------------------------------------------------ */
+
+  _onSelectMove(e) {
+    const map = this.getMap();
+    if (!map) return true;
+
+    this._overlaySource.clear();
+
+    const hit = this._closestPolygon(e);
+    if (hit) {
+      const clone = hit.feature.clone();
+      this._overlaySource.addFeature(clone);
+      map.getTargetElement().style.cursor = 'pointer';
+    } else {
+      map.getTargetElement().style.cursor = '';
+    }
+    return true;
+  }
+
+  _onSelectClick(e) {
+    const hit = this._closestPolygon(e);
+    if (!hit) return true;
+
+    this._selectedFeature = hit.feature;
+    this._selectedSource = hit.source;
+
+    // Keep polygon highlight visible during edge phase
+    this._overlaySource.clear();
+    const clone = hit.feature.clone();
+    clone.set('_permanent', true);
+    this._overlaySource.addFeature(clone);
+
+    this._phase = 'edge';
+    showToast('Click the edge to divide along.', 'info', 3000);
+    return false;
+  }
+
+  _closestPolygon(e) {
+    let best = null;
+    let bestDist = this.snapDistance_ + 1;
+
+    for (const source of this._getSources()) {
+      const feat = source.getClosestFeatureToCoordinate(e.coordinate);
+      if (!feat) continue;
+      const geom = feat.getGeometry();
+      if (!geom) continue;
+      const type = geom.getType();
+      if (type !== 'Polygon' && type !== 'MultiPolygon') continue;
+
+      const closest = geom.getClosestPoint(e.coordinate);
+      const line = new LineString([e.coordinate, closest]);
+      const distPx = line.getLength() / e.frameState.viewState.resolution;
+
+      if (distPx < bestDist) {
+        bestDist = distPx;
+        best = { feature: feat, source };
+      }
+    }
+    return best;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Phase 2: EDGE selection                                            */
+  /* ------------------------------------------------------------------ */
+
+  _onEdgeMove(e) {
+    const map = this.getMap();
+    if (!map) return true;
+
+    this._edgeSource.clear();
+
+    const edge = this._closestEdgeSegment(this._selectedFeature, e);
+    if (edge) {
+      const edgeFeat = new Feature(new LineString([edge.segStart, edge.segEnd]));
+      this._edgeSource.addFeature(edgeFeat);
+      map.getTargetElement().style.cursor = 'crosshair';
+    } else {
+      map.getTargetElement().style.cursor = '';
+    }
+    return true;
+  }
+
+  _onEdgeClick(e) {
+    const edge = this._closestEdgeSegment(this._selectedFeature, e);
+    if (!edge) return true;
+
+    this._selectedEdge = [edge.segStart, edge.segEnd];
+    this._edgeSource.clear();
+
+    this._phase = 'form';
+
+    // Dispatch divideform so MapView can show the popup
+    const geom = this._selectedFeature.getGeometry();
+    const ext = geom.getExtent();
+    const center = [(ext[0] + ext[2]) / 2, (ext[1] + ext[3]) / 2];
+
+    this.dispatchEvent({
+      type: 'divideform',
+      feature: this._selectedFeature,
+      source: this._selectedSource,
+      coordinate: center,
+    });
+
+    return false;
+  }
+
+  /**
+   * Find the closest edge segment of a polygon feature to the cursor.
+   */
+  _closestEdgeSegment(feature, e) {
+    const geom = feature.getGeometry();
+    let ring;
+    if (geom.getType() === 'Polygon') {
+      ring = geom.getCoordinates()[0];
+    } else if (geom.getType() === 'MultiPolygon') {
+      ring = geom.getCoordinates()[0][0];
+    } else {
+      return null;
+    }
+
+    const resolution = e.frameState.viewState.resolution;
+    let bestDist = Infinity;
+    let bestSeg = null;
+    const n = ring.length - 1;
+
+    for (let i = 0; i < n; i++) {
+      const a = ring[i];
+      const b = ring[i + 1];
+      const dx = b[0] - a[0], dy = b[1] - a[1];
+      const lenSq = dx * dx + dy * dy;
+      if (lenSq < 1e-20) continue;
+
+      let t = ((e.coordinate[0] - a[0]) * dx + (e.coordinate[1] - a[1]) * dy) / lenSq;
+      t = Math.max(0, Math.min(1, t));
+      const projX = a[0] + t * dx, projY = a[1] + t * dy;
+      const distPx = Math.sqrt((e.coordinate[0] - projX) ** 2 + (e.coordinate[1] - projY) ** 2) / resolution;
+
+      if (distPx < bestDist) {
+        bestDist = distPx;
+        bestSeg = { segStart: a, segEnd: b };
+      }
+    }
+    return bestDist <= this.snapDistance_ ? bestSeg : null;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Phase 3: FORM — called externally by the popup                     */
+  /* ------------------------------------------------------------------ */
+
+  /**
+   * Divide the selected polygon into `n` equal-area pieces.
+   * Called by the MapView popup's Confirm handler.
+   *
+   * @param {number} n  Number of pieces (>= 2)
+   */
+  performDivide(n) {
+    if (this._phase !== 'form' || !this._selectedFeature) return;
+
+    const feature = this._selectedFeature;
+    const source = this._selectedSource;
+    const geom = feature.getGeometry();
+
+    let polygonCoords;
+    if (geom.getType() === 'Polygon') {
+      polygonCoords = geom.getCoordinates();
+    } else if (geom.getType() === 'MultiPolygon') {
+      polygonCoords = geom.getCoordinates()[0];
+    }
+
+    const result = dividePolygon(polygonCoords, n, this._selectedEdge);
+
+    if (!result.pieces) {
+      showToast(result.error || 'Division failed.', 'error', 5000);
+      this._reset();
+      return;
+    }
+
+    // Create N new coloured features
+    const colors = pieceColors(n);
+    const newFeatures = result.pieces.map((coords, i) => {
+      const f = feature.clone();
+      f.setGeometry(new PolygonGeom(coords));
+      f.setStyle(new Style({
+        stroke: new Stroke({ color: colors[i].stroke, width: 2.5 }),
+        fill: new Fill({ color: colors[i].fill }),
+      }));
+      return f;
+    });
+
+    // Dispatch beforedivide (UndoRedo compatible)
+    const evtData = {
+      type: 'beforedivide',
+      original: feature,
+      features: newFeatures,
+    };
+    this.dispatchEvent(evtData);
+    source.dispatchEvent({ ...evtData });
+
+    // Replace original with pieces
+    source.removeFeature(feature);
+    for (const f of newFeatures) {
+      source.addFeature(f);
+    }
+
+    // Dispatch afterdivide
+    const afterEvt = {
+      type: 'afterdivide',
+      original: feature,
+      features: newFeatures,
+    };
+    this.dispatchEvent(afterEvt);
+    source.dispatchEvent({ ...afterEvt });
+
+    // If original was a parcel, enter pick phase for UPN assignment
+    const isParcel = feature.get('_layerType') === 'parcel';
+    if (isParcel) {
+      this._dividedFeatures = newFeatures;
+      this._phase = 'pick';
+      showToast('Click the polygon that should keep the original identifier.', 'info', 5000);
+
+      this.dispatchEvent({
+        type: 'dividedparcel',
+        features: newFeatures,
+        originalProps: feature.getProperties(),
+        source,
+      });
+    } else {
+      showToast(`Polygon divided into ${n} equal pieces.`, 'success');
+      this._reset();
+    }
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Phase 4: PICK — select which piece keeps the UPN                   */
+  /* ------------------------------------------------------------------ */
+
+  _onPickMove(e) {
+    const map = this.getMap();
+    if (!map) return true;
+
+    this._overlaySource.clear();
+
+    // Highlight whichever divided piece is under the cursor
+    const hit = this._closestDividedPiece(e);
+    if (hit) {
+      const clone = hit.clone();
+      this._overlaySource.addFeature(clone);
+      map.getTargetElement().style.cursor = 'pointer';
+    } else {
+      map.getTargetElement().style.cursor = '';
+    }
+    return true;
+  }
+
+  _onPickClick(e) {
+    const hit = this._closestDividedPiece(e);
+    if (!hit) return true;
+
+    this.dispatchEvent({
+      type: 'dividepick',
+      picked: hit,
+      features: this._dividedFeatures,
+    });
+
+    this._reset();
+    return false;
+  }
+
+  /**
+   * Find the closest divided piece to the cursor.
+   */
+  _closestDividedPiece(e) {
+    if (!this._dividedFeatures) return null;
+    let best = null;
+    let bestDist = this.snapDistance_ + 1;
+
+    for (const feat of this._dividedFeatures) {
+      const geom = feat.getGeometry();
+      if (!geom) continue;
+      const closest = geom.getClosestPoint(e.coordinate);
+      const line = new LineString([e.coordinate, closest]);
+      const distPx = line.getLength() / e.frameState.viewState.resolution;
+      if (distPx < bestDist) {
+        bestDist = distPx;
+        best = feat;
+      }
+    }
+    return best;
+  }
+
+  /**
+   * Cancel the divide operation and return to select phase.
+   * Called by the MapView popup's Cancel handler.
+   */
+  cancelDivide() {
+    this.dispatchEvent({ type: 'dividecancel' });
+    this._reset();
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Reset                                                              */
+  /* ------------------------------------------------------------------ */
+
+  _reset() {
+    this._phase = 'select';
+    this._selectedFeature = null;
+    this._selectedSource = null;
+    this._selectedEdge = null;
+    this._dividedFeatures = null;
+    this._overlaySource.clear();
+    this._edgeSource.clear();
+
+    const map = this.getMap();
+    if (map) {
+      map.getTargetElement().style.cursor = '';
+    }
+  }
+}
--- a/src/interactions/PolygonMergeInteraction.js
+++ b/src/interactions/PolygonMergeInteraction.js
@ -0,0 +1,475 @@
+/**
+ * PolygonMergeInteraction
+ *
+ * A four-phase OpenLayers interaction for merging two adjacent polygons:
+ *   Phase 1 – SELECT_A:     hover to highlight, click to select polygon A
+ *   Phase 2 – SELECT_B:     hover to highlight, click to select polygon B
+ *   Phase 3 – CLICK_EDGE_A: hover highlights edge, click to pick shared edge on A
+ *   Phase 4 – CLICK_EDGE_B: hover highlights edge, click to pick shared edge on B → merge
+ *
+ * After a successful merge the two original features are removed and one
+ * merged feature (coloured green) is added.  If both originals were parcels,
+ * a `mergedparcel` event is fired so external code can present a UPN chooser.
+ */
+
+import ol_interaction_Interaction from 'ol/interaction/Interaction';
+import VectorSource from 'ol/source/Vector';
+import VectorLayer from 'ol/layer/Vector';
+import Feature from 'ol/Feature';
+import { Style, Stroke, Fill, Text } from 'ol/style';
+import { LineString, Polygon as PolygonGeom } from 'ol/geom';
+import { mergePolygons } from '../geom/polygonMerge.js';
+import { showToast } from '../toast.js';
+
+// ── Styles ───────────────────────────────────────────────────────────────────
+
+const HIGHLIGHT_A = new Style({
+  stroke: new Stroke({ color: '#0ea5e9', width: 3 }),
+  fill: new Fill({ color: 'rgba(14,165,233,0.15)' }),
+});
+
+const HIGHLIGHT_B = new Style({
+  stroke: new Stroke({ color: '#f59e0b', width: 3 }),
+  fill: new Fill({ color: 'rgba(245,158,11,0.15)' }),
+});
+
+// Labelled versions for permanent highlights (shown after selection)
+const LABEL_A = new Style({
+  stroke: new Stroke({ color: '#0ea5e9', width: 3 }),
+  fill: new Fill({ color: 'rgba(14,165,233,0.15)' }),
+  text: new Text({
+    text: 'A',
+    font: 'bold 22px Exo, sans-serif',
+    fill: new Fill({ color: '#0ea5e9' }),
+    stroke: new Stroke({ color: '#fff', width: 4 }),
+    overflow: true,
+  }),
+});
+
+const LABEL_B = new Style({
+  stroke: new Stroke({ color: '#f59e0b', width: 3 }),
+  fill: new Fill({ color: 'rgba(245,158,11,0.15)' }),
+  text: new Text({
+    text: 'B',
+    font: 'bold 22px Exo, sans-serif',
+    fill: new Fill({ color: '#f59e0b' }),
+    stroke: new Stroke({ color: '#fff', width: 4 }),
+    overflow: true,
+  }),
+});
+
+const EDGE_STYLE = new Style({
+  stroke: new Stroke({ color: '#ec4899', width: 4, lineDash: [10, 6] }),
+});
+
+const MERGE_STYLE = new Style({
+  stroke: new Stroke({ color: '#10b981', width: 2.5 }),
+  fill: new Fill({ color: 'rgba(16,185,129,0.3)' }),
+});
+
+// ── Interaction ──────────────────────────────────────────────────────────────
+
+export class PolygonMergeInteraction extends ol_interaction_Interaction {
+  /**
+   * @param {Object} [options]
+   * @param {number} [options.snapDistance=25]  Pixel distance for hover detection.
+   * @param {number} [options.tolerance=5]     Map-unit tolerance for shared-edge matching.
+   */
+  constructor(options = {}) {
+    super({
+      handleEvent: (e) => this._handleEvent(e),
+    });
+
+    this.snapDistance_ = options.snapDistance || 25;
+    this.tolerance_ = options.tolerance || 5;
+
+    // Phase: 'select_a' | 'select_b' | 'click_edge_a' | 'click_edge_b'
+    this._phase = 'select_a';
+
+    // Selected features and their sources
+    this._featureA = null;
+    this._sourceA = null;
+    this._featureB = null;
+    this._sourceB = null;
+
+    // Clicked edge coordinates (map coords)
+    this._edgeClickA = null;
+    this._edgeClickB = null;
+
+    // Overlay for polygon highlights
+    this._highlightSource = new VectorSource({ useSpatialIndex: false });
+    this._highlightLayer = new VectorLayer({
+      source: this._highlightSource,
+      displayInLayerSwitcher: false,
+      style: (f) => f.get('_highlightStyle') || HIGHLIGHT_A,
+    });
+
+    // Overlay for edge highlights
+    this._edgeSource = new VectorSource({ useSpatialIndex: false });
+    this._edgeLayer = new VectorLayer({
+      source: this._edgeSource,
+      displayInLayerSwitcher: false,
+      style: EDGE_STYLE,
+    });
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Map lifecycle                                                      */
+  /* ------------------------------------------------------------------ */
+
+  setMap(map) {
+    if (this.getMap()) {
+      this.getMap().removeLayer(this._highlightLayer);
+      this.getMap().removeLayer(this._edgeLayer);
+    }
+    super.setMap(map);
+    if (map) {
+      this._highlightLayer.setMap(map);
+      this._edgeLayer.setMap(map);
+    }
+  }
+
+  setActive(active) {
+    super.setActive(active);
+    if (!active) this._reset();
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Source helpers                                                      */
+  /* ------------------------------------------------------------------ */
+
+  _getSources() {
+    if (!this.getMap()) return [];
+    const sources = [];
+    const collect = (layers) => {
+      layers.forEach((layer) => {
+        if (layer.getVisible()) {
+          if (layer.getSource && layer.getSource() instanceof VectorSource) {
+            sources.push(layer.getSource());
+          } else if (layer.getLayers) {
+            collect(layer.getLayers());
+          }
+        }
+      });
+    };
+    collect(this.getMap().getLayers());
+    return sources;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Event router                                                       */
+  /* ------------------------------------------------------------------ */
+
+  _handleEvent(e) {
+    if (!this.getActive()) return true;
+
+    // Escape cancels at any phase
+    if (e.type === 'keydown' && e.originalEvent?.key === 'Escape') {
+      this._reset();
+      return false;
+    }
+
+    switch (this._phase) {
+      case 'select_a':
+        if (e.type === 'pointermove') return this._onSelectMove(e, null);
+        if (e.type === 'singleclick') return this._onSelectAClick(e);
+        break;
+      case 'select_b':
+        if (e.type === 'pointermove') return this._onSelectMove(e, this._featureA);
+        if (e.type === 'singleclick') return this._onSelectBClick(e);
+        break;
+      case 'click_edge_a':
+        if (e.type === 'pointermove') return this._onEdgeMove(e, this._featureA);
+        if (e.type === 'singleclick') return this._onEdgeAClick(e);
+        break;
+      case 'click_edge_b':
+        if (e.type === 'pointermove') return this._onEdgeMove(e, this._featureB);
+        if (e.type === 'singleclick') return this._onEdgeBClick(e);
+        break;
+    }
+    return true;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Phase 1 & 2: SELECT polygons                                       */
+  /* ------------------------------------------------------------------ */
+
+  _onSelectMove(e, skipFeature) {
+    const map = this.getMap();
+    if (!map) return true;
+
+    // Keep existing highlights for already-selected polygons
+    this._highlightSource.clear();
+    this._edgeSource.clear();
+    this._rebuildHighlights();
+
+    const hit = this._closestPolygon(e, skipFeature);
+    if (hit) {
+      const style = this._phase === 'select_a' ? HIGHLIGHT_A : HIGHLIGHT_B;
+      const clone = hit.feature.clone();
+      clone.set('_highlightStyle', style);
+      this._highlightSource.addFeature(clone);
+      map.getTargetElement().style.cursor = 'pointer';
+    } else {
+      map.getTargetElement().style.cursor = '';
+    }
+    return true;
+  }
+
+  _onSelectAClick(e) {
+    const hit = this._closestPolygon(e, null);
+    if (!hit) return true;
+
+    this._featureA = hit.feature;
+    this._sourceA = hit.source;
+    this._phase = 'select_b';
+
+    this._rebuildHighlights();
+    return false;
+  }
+
+  _onSelectBClick(e) {
+    const hit = this._closestPolygon(e, this._featureA);
+    if (!hit) return true;
+
+    this._featureB = hit.feature;
+    this._sourceB = hit.source;
+    this._phase = 'click_edge_a';
+
+    this._rebuildHighlights();
+    this.getMap().getTargetElement().style.cursor = 'crosshair';
+    return false;
+  }
+
+  /**
+   * Find the closest polygon feature within snap distance.
+   * Optionally skip a feature (used in phase 2 to avoid re-selecting A).
+   */
+  _closestPolygon(e, skipFeature) {
+    let best = null;
+    let bestDist = this.snapDistance_ + 1;
+
+    for (const source of this._getSources()) {
+      const feat = source.getClosestFeatureToCoordinate(e.coordinate);
+      if (!feat) continue;
+      if (skipFeature && feat === skipFeature) continue;
+      const geom = feat.getGeometry();
+      if (!geom) continue;
+      const type = geom.getType();
+      if (type !== 'Polygon' && type !== 'MultiPolygon') continue;
+
+      const closest = geom.getClosestPoint(e.coordinate);
+      const line = new LineString([e.coordinate, closest]);
+      const distPx = line.getLength() / e.frameState.viewState.resolution;
+
+      if (distPx < bestDist) {
+        bestDist = distPx;
+        best = { feature: feat, source, coord: closest };
+      }
+    }
+    return best;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Phase 3 & 4: CLICK edges                                          */
+  /* ------------------------------------------------------------------ */
+
+  _onEdgeMove(e, feature) {
+    const map = this.getMap();
+    if (!map) return true;
+
+    this._edgeSource.clear();
+
+    const edge = this._closestEdgeSegment(feature, e);
+    if (edge) {
+      const edgeFeat = new Feature(new LineString([edge.segStart, edge.segEnd]));
+      this._edgeSource.addFeature(edgeFeat);
+      map.getTargetElement().style.cursor = 'crosshair';
+    }
+    return true;
+  }
+
+  _onEdgeAClick(e) {
+    this._edgeClickA = e.coordinate;
+    this._phase = 'click_edge_b';
+    this._edgeSource.clear();
+    return false;
+  }
+
+  _onEdgeBClick(e) {
+    this._edgeClickB = e.coordinate;
+    this._performMerge();
+    return false;
+  }
+
+  /**
+   * Find the closest edge segment of a polygon feature to the cursor.
+   */
+  _closestEdgeSegment(feature, e) {
+    const geom = feature.getGeometry();
+    let ring;
+    if (geom.getType() === 'Polygon') {
+      ring = geom.getCoordinates()[0];
+    } else if (geom.getType() === 'MultiPolygon') {
+      ring = geom.getCoordinates()[0][0];
+    } else {
+      return null;
+    }
+
+    const resolution = e.frameState.viewState.resolution;
+    let bestDist = Infinity;
+    let bestSeg = null;
+    const n = ring.length - 1;
+
+    for (let i = 0; i < n; i++) {
+      const a = ring[i];
+      const b = ring[i + 1];
+      const dx = b[0] - a[0], dy = b[1] - a[1];
+      const lenSq = dx * dx + dy * dy;
+      if (lenSq < 1e-20) continue;
+
+      let t = ((e.coordinate[0] - a[0]) * dx + (e.coordinate[1] - a[1]) * dy) / lenSq;
+      t = Math.max(0, Math.min(1, t));
+      const projX = a[0] + t * dx, projY = a[1] + t * dy;
+      const distPx = Math.sqrt((e.coordinate[0] - projX) ** 2 + (e.coordinate[1] - projY) ** 2) / resolution;
+
+      if (distPx < bestDist) {
+        bestDist = distPx;
+        bestSeg = { segStart: a, segEnd: b };
+      }
+    }
+    return bestDist <= this.snapDistance_ ? bestSeg : null;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Merge logic                                                        */
+  /* ------------------------------------------------------------------ */
+
+  _performMerge() {
+    const featureA = this._featureA;
+    const featureB = this._featureB;
+    const sourceA = this._sourceA;
+    const sourceB = this._sourceB;
+
+    // Extract polygon coordinates
+    const geomA = featureA.getGeometry();
+    const geomB = featureB.getGeometry();
+    const coordsA = geomA.getType() === 'Polygon' ? geomA.getCoordinates() : geomA.getCoordinates()[0];
+    const coordsB = geomB.getType() === 'Polygon' ? geomB.getCoordinates() : geomB.getCoordinates()[0];
+
+    const result = mergePolygons(coordsA, coordsB, this._edgeClickA, this._edgeClickB, this.tolerance_);
+
+    if (!result.coords) {
+      showToast(result.error || 'Merge failed — try clicking on the shared boundary.', 'error', 5000);
+      // Return to edge click phase for retry
+      this._edgeClickA = null;
+      this._edgeClickB = null;
+      this._phase = 'click_edge_a';
+      this._edgeSource.clear();
+      return;
+    }
+
+    // Create merged feature (clone A for default properties)
+    const mergedFeature = featureA.clone();
+    mergedFeature.setGeometry(new PolygonGeom(result.coords));
+    mergedFeature.setStyle(MERGE_STYLE);
+
+    // Dispatch beforemerge events
+    const evtData = {
+      type: 'beforemerge',
+      original: [featureA, featureB],
+      merged: mergedFeature,
+    };
+    this.dispatchEvent(evtData);
+    sourceA.dispatchEvent({ ...evtData });
+    if (sourceB !== sourceA) {
+      sourceB.dispatchEvent({ ...evtData });
+    }
+
+    // Replace originals with merged
+    sourceA.removeFeature(featureA);
+    sourceB.removeFeature(featureB);
+    sourceA.addFeature(mergedFeature);
+
+    // Dispatch aftermerge events
+    const afterEvt = {
+      type: 'aftermerge',
+      original: [featureA, featureB],
+      merged: mergedFeature,
+    };
+    this.dispatchEvent(afterEvt);
+    sourceA.dispatchEvent({ ...afterEvt });
+    if (sourceB !== sourceA) {
+      sourceB.dispatchEvent({ ...afterEvt });
+    }
+
+    // If both features were parcels, fire mergedparcel so MapView can show the UPN chooser
+    const isParcelA = featureA.get('_layerType') === 'parcel';
+    const isParcelB = featureB.get('_layerType') === 'parcel';
+    if (isParcelA && isParcelB) {
+      this.dispatchEvent({
+        type: 'mergedparcel',
+        merged: mergedFeature,
+        propsA: featureA.getProperties(),
+        propsB: featureB.getProperties(),
+        coordinate: this._edgeClickA,
+      });
+      showToast('Polygons merged — choose which identifier to keep.', 'success');
+    } else {
+      showToast('Polygons merged successfully.', 'success');
+    }
+
+    // Clean up
+    this._reset();
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Highlight management                                               */
+  /* ------------------------------------------------------------------ */
+
+  /**
+   * Rebuild the permanent highlights for already-selected polygons.
+   */
+  _rebuildHighlights() {
+    // Remove previous non-hover highlights
+    const toRemove = [];
+    this._highlightSource.getFeatures().forEach((f) => {
+      if (f.get('_permanent')) toRemove.push(f);
+    });
+    toRemove.forEach((f) => this._highlightSource.removeFeature(f));
+
+    if (this._featureA) {
+      const cloneA = this._featureA.clone();
+      cloneA.set('_highlightStyle', LABEL_A);
+      cloneA.set('_permanent', true);
+      this._highlightSource.addFeature(cloneA);
+    }
+    if (this._featureB) {
+      const cloneB = this._featureB.clone();
+      cloneB.set('_highlightStyle', LABEL_B);
+      cloneB.set('_permanent', true);
+      this._highlightSource.addFeature(cloneB);
+    }
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Reset                                                              */
+  /* ------------------------------------------------------------------ */
+
+  _reset() {
+    this._phase = 'select_a';
+    this._featureA = null;
+    this._sourceA = null;
+    this._featureB = null;
+    this._sourceB = null;
+    this._edgeClickA = null;
+    this._edgeClickB = null;
+    this._highlightSource.clear();
+    this._edgeSource.clear();
+
+    const map = this.getMap();
+    if (map) {
+      map.getTargetElement().style.cursor = '';
+    }
+  }
+}
--- a/src/interactions/PolygonSplitInteraction.js
+++ b/src/interactions/PolygonSplitInteraction.js
@ -0,0 +1,433 @@
+/**
+ * PolygonSplitInteraction
+ *
+ * A two-phase OpenLayers interaction for splitting polygons:
+ *   Phase 1 – SELECT: hover to highlight, click to select a polygon
+ *   Phase 2 – DRAW:   draw a cutting line, double-click to finish
+ *
+ * After a successful split the original feature is removed and two new
+ * coloured features are added.  The interaction fires `beforesplit` and
+ * `aftersplit` events compatible with ol-ext's UndoRedo.
+ */
+
+import ol_interaction_Interaction from 'ol/interaction/Interaction';
+import ol_interaction_Draw from 'ol/interaction/Draw';
+import VectorSource from 'ol/source/Vector';
+import VectorLayer from 'ol/layer/Vector';
+import Feature from 'ol/Feature';
+import { Style, Stroke, Fill, Circle as CircleStyle } from 'ol/style';
+import { LineString } from 'ol/geom';
+import { Polygon as PolygonGeom } from 'ol/geom';
+import { splitPolygonByLine } from '../geom/polygonSplit.js';
+import { showToast } from '../toast.js';
+
+// Marker colours for the two split pieces
+const SPLIT_COLORS = [
+  { stroke: '#ef4444', fill: 'rgba(239,68,68,0.25)' },   // red
+  { stroke: '#3b82f6', fill: 'rgba(59,130,246,0.25)' },   // blue
+];
+
+// Highlight style for the selected polygon (phase 1)
+const HIGHLIGHT_STYLE = new Style({
+  stroke: new Stroke({ color: '#0ea5e9', width: 3 }),
+  fill: new Fill({ color: 'rgba(14,165,233,0.15)' }),
+});
+
+// Style for the cutting-line sketch (phase 2)
+const SKETCH_STYLE = new Style({
+  stroke: new Stroke({ color: '#f43f5e', width: 2, lineDash: [8, 6] }),
+  image: new CircleStyle({
+    radius: 5,
+    fill: new Fill({ color: '#f43f5e' }),
+    stroke: new Stroke({ color: '#fff', width: 1.5 }),
+  }),
+});
+
+export class PolygonSplitInteraction extends ol_interaction_Interaction {
+  /**
+   * @param {Object} options
+   * @param {VectorSource|VectorSource[]} [options.sources]  Sources containing
+   *   polygons to split.  If omitted the interaction searches all visible
+   *   vector layers on the map.
+   * @param {number} [options.snapDistance=25]  Pixel distance for hover highlight.
+   */
+  constructor(options = {}) {
+    super({
+      handleEvent: (e) => this._handleEvent(e),
+    });
+
+    this.snapDistance_ = options.snapDistance || 25;
+    this._sources = options.sources
+      ? (Array.isArray(options.sources) ? options.sources : [options.sources])
+      : null;
+
+    // Phase: 'select' | 'draw' | 'pick'
+    this._phase = 'select';
+    this._selectedFeature = null;
+    this._selectedSource = null;
+    this._drawInteraction = null;
+    this._splitFeatures = null; // the two pieces (for pick phase)
+
+    // Overlay layer for highlighting the polygon under the cursor / selected
+    this._overlaySource = new VectorSource({ useSpatialIndex: false });
+    this._overlayLayer = new VectorLayer({
+      source: this._overlaySource,
+      displayInLayerSwitcher: false,
+      style: HIGHLIGHT_STYLE,
+    });
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Map lifecycle                                                      */
+  /* ------------------------------------------------------------------ */
+
+  setMap(map) {
+    if (this.getMap()) {
+      this.getMap().removeLayer(this._overlayLayer);
+      this._removeDrawInteraction();
+    }
+    super.setMap(map);
+    if (map) {
+      this._overlayLayer.setMap(map);
+    }
+  }
+
+  setActive(active) {
+    super.setActive(active);
+    if (!active) {
+      this._reset();
+    }
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Source helpers                                                      */
+  /* ------------------------------------------------------------------ */
+
+  _getSources() {
+    if (this._sources) return this._sources;
+    if (!this.getMap()) return [];
+    const sources = [];
+    const collect = (layers) => {
+      layers.forEach((layer) => {
+        if (layer.getVisible()) {
+          if (layer.getSource && layer.getSource() instanceof VectorSource) {
+            sources.push(layer.getSource());
+          } else if (layer.getLayers) {
+            collect(layer.getLayers());
+          }
+        }
+      });
+    };
+    collect(this.getMap().getLayers());
+    return sources;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Event router                                                       */
+  /* ------------------------------------------------------------------ */
+
+  _handleEvent(e) {
+    if (!this.getActive()) return true;
+
+    if (this._phase === 'select') {
+      if (e.type === 'pointermove') return this._onSelectMove(e);
+      if (e.type === 'singleclick') return this._onSelectClick(e);
+    }
+    // In 'draw' phase the Draw interaction handles events directly;
+    // we only intercept Escape to cancel.
+    if (this._phase === 'draw') {
+      if (e.type === 'keydown' && e.originalEvent?.key === 'Escape') {
+        this._cancelDraw();
+        return false;
+      }
+    }
+
+    // In 'pick' phase the user selects which split piece keeps the UPN
+    if (this._phase === 'pick') {
+      if (e.type === 'pointermove') return this._onPickMove(e);
+      if (e.type === 'singleclick') return this._onPickClick(e);
+      if (e.type === 'keydown' && e.originalEvent?.key === 'Escape') {
+        this._reset();
+        return false;
+      }
+    }
+
+    return true;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Phase 1: SELECT                                                    */
+  /* ------------------------------------------------------------------ */
+
+  _onSelectMove(e) {
+    const map = this.getMap();
+    if (!map) return true;
+
+    this._overlaySource.clear();
+
+    const hit = this._closestPolygon(e);
+    if (hit) {
+      // Show highlight copy
+      const clone = hit.feature.clone();
+      this._overlaySource.addFeature(clone);
+      map.getTargetElement().style.cursor = 'pointer';
+    } else {
+      map.getTargetElement().style.cursor = '';
+    }
+    return true;
+  }
+
+  _onSelectClick(e) {
+    const hit = this._closestPolygon(e);
+    if (!hit) return true;
+
+    this._selectedFeature = hit.feature;
+    this._selectedSource = hit.source;
+
+    // Keep highlight visible during draw phase
+    this._overlaySource.clear();
+    const clone = hit.feature.clone();
+    this._overlaySource.addFeature(clone);
+
+    this._startDrawPhase();
+    return false; // consume the click
+  }
+
+  /**
+   * Find the closest polygon feature within snap distance.
+   */
+  _closestPolygon(e) {
+    let best = null;
+    let bestDist = this.snapDistance_ + 1;
+
+    for (const source of this._getSources()) {
+      const feat = source.getClosestFeatureToCoordinate(e.coordinate);
+      if (!feat) continue;
+      const geom = feat.getGeometry();
+      if (!geom) continue;
+      const type = geom.getType();
+      if (type !== 'Polygon' && type !== 'MultiPolygon') continue;
+
+      const closest = geom.getClosestPoint(e.coordinate);
+      const line = new LineString([e.coordinate, closest]);
+      const distPx = line.getLength() / e.frameState.viewState.resolution;
+
+      if (distPx < bestDist) {
+        bestDist = distPx;
+        best = { feature: feat, source, coord: closest };
+      }
+    }
+    return best;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Phase 2: DRAW cutting line                                         */
+  /* ------------------------------------------------------------------ */
+
+  _startDrawPhase() {
+    this._phase = 'draw';
+    const map = this.getMap();
+    if (!map) return;
+
+    map.getTargetElement().style.cursor = 'crosshair';
+
+    this._drawInteraction = new ol_interaction_Draw({
+      type: 'LineString',
+      style: SKETCH_STYLE,
+    });
+
+    this._drawInteraction.on('drawend', (evt) => {
+      const cuttingLine = evt.feature.getGeometry().getCoordinates();
+      this._performSplit(cuttingLine);
+    });
+
+    map.addInteraction(this._drawInteraction);
+  }
+
+  _removeDrawInteraction() {
+    if (this._drawInteraction && this.getMap()) {
+      this.getMap().removeInteraction(this._drawInteraction);
+    }
+    this._drawInteraction = null;
+  }
+
+  _cancelDraw() {
+    this._removeDrawInteraction();
+    this._reset();
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Split logic                                                        */
+  /* ------------------------------------------------------------------ */
+
+  _performSplit(cuttingLineCoords) {
+    const feature = this._selectedFeature;
+    const source = this._selectedSource;
+    const geom = feature.getGeometry();
+
+    let polygonCoords;
+    if (geom.getType() === 'Polygon') {
+      polygonCoords = geom.getCoordinates();
+    } else if (geom.getType() === 'MultiPolygon') {
+      // For MultiPolygon, try to split each sub-polygon and use the
+      // first one that produces a valid result.
+      // For now, use the first polygon ring.
+      polygonCoords = geom.getCoordinates()[0];
+    }
+
+    const result = splitPolygonByLine(polygonCoords, cuttingLineCoords);
+
+    if (!result) {
+      console.warn('[PolygonSplit] Split failed — line must cross the polygon boundary at exactly 2 points.');
+      // Stay in draw phase so user can retry
+      this._removeDrawInteraction();
+      this._startDrawPhase();
+      return;
+    }
+
+    const [coordsA, coordsB] = result;
+
+    // Create two new features from the split result
+    const featureA = feature.clone();
+    featureA.setGeometry(new PolygonGeom(coordsA));
+    featureA.setStyle(new Style({
+      stroke: new Stroke({ color: SPLIT_COLORS[0].stroke, width: 2.5 }),
+      fill: new Fill({ color: SPLIT_COLORS[0].fill }),
+    }));
+
+    const featureB = feature.clone();
+    featureB.setGeometry(new PolygonGeom(coordsB));
+    featureB.setStyle(new Style({
+      stroke: new Stroke({ color: SPLIT_COLORS[1].stroke, width: 2.5 }),
+      fill: new Fill({ color: SPLIT_COLORS[1].fill }),
+    }));
+
+    // Dispatch beforesplit (compatible with ol-ext UndoRedo)
+    const splitFeatures = [featureA, featureB];
+    this.dispatchEvent({
+      type: 'beforesplit',
+      original: feature,
+      features: splitFeatures,
+    });
+    source.dispatchEvent({
+      type: 'beforesplit',
+      original: feature,
+      features: splitFeatures,
+    });
+
+    // Replace the original feature
+    source.removeFeature(feature);
+    source.addFeature(featureA);
+    source.addFeature(featureB);
+
+    // Dispatch aftersplit
+    this.dispatchEvent({
+      type: 'aftersplit',
+      original: feature,
+      features: splitFeatures,
+    });
+    source.dispatchEvent({
+      type: 'aftersplit',
+      original: feature,
+      features: splitFeatures,
+    });
+
+    // Clean up draw interaction
+    this._removeDrawInteraction();
+
+    // If the original was a parcel, enter pick phase for UPN assignment
+    const isParcel = feature.get('_layerType') === 'parcel';
+    if (isParcel) {
+      this._splitFeatures = splitFeatures;
+      this._phase = 'pick';
+      this._overlaySource.clear();
+      const map = this.getMap();
+      if (map) map.getTargetElement().style.cursor = '';
+      showToast('Click the polygon that should keep the original identifier.', 'info', 5000);
+
+      this.dispatchEvent({
+        type: 'splitparcel',
+        features: splitFeatures,
+        originalProps: feature.getProperties(),
+        source,
+      });
+    } else {
+      this._reset();
+    }
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Phase 3: PICK — select which split piece keeps the UPN             */
+  /* ------------------------------------------------------------------ */
+
+  _onPickMove(e) {
+    const map = this.getMap();
+    if (!map) return true;
+
+    this._overlaySource.clear();
+
+    const hit = this._closestSplitPiece(e);
+    if (hit) {
+      const clone = hit.clone();
+      this._overlaySource.addFeature(clone);
+      map.getTargetElement().style.cursor = 'pointer';
+    } else {
+      map.getTargetElement().style.cursor = '';
+    }
+    return true;
+  }
+
+  _onPickClick(e) {
+    const hit = this._closestSplitPiece(e);
+    if (!hit) return true;
+
+    this.dispatchEvent({
+      type: 'splitpick',
+      picked: hit,
+      features: this._splitFeatures,
+    });
+
+    this._reset();
+    return false;
+  }
+
+  /**
+   * Find the closest split piece to the cursor.
+   */
+  _closestSplitPiece(e) {
+    if (!this._splitFeatures) return null;
+    let best = null;
+    let bestDist = this.snapDistance_ + 1;
+
+    for (const feat of this._splitFeatures) {
+      const geom = feat.getGeometry();
+      if (!geom) continue;
+      const closest = geom.getClosestPoint(e.coordinate);
+      const line = new LineString([e.coordinate, closest]);
+      const distPx = line.getLength() / e.frameState.viewState.resolution;
+      if (distPx < bestDist) {
+        bestDist = distPx;
+        best = feat;
+      }
+    }
+    return best;
+  }
+
+  /* ------------------------------------------------------------------ */
+  /*  Reset                                                              */
+  /* ------------------------------------------------------------------ */
+
+  _reset() {
+    this._phase = 'select';
+    this._selectedFeature = null;
+    this._selectedSource = null;
+    this._splitFeatures = null;
+    this._overlaySource.clear();
+    this._removeDrawInteraction();
+
+    const map = this.getMap();
+    if (map) {
+      map.getTargetElement().style.cursor = '';
+    }
+  }
+}
--- a/src/offlineTiles.js
+++ b/src/offlineTiles.js
@ -0,0 +1,293 @@
+/**
+ * Offline Tile Downloader
+ *
+ * Pre-fetches map tiles for a given extent and zoom range so they are stored
+ * in the Service Worker's per-host tile cache for offline use.
+ *
+ * The downloader simply issues `fetch()` calls; the existing SW intercepts
+ * them and routes to the right cache bucket. No direct Cache API access is
+ * needed here — the SW is the single source of truth for storage.
+ *
+ * Throttling defaults are conservative to respect tile-server usage policies:
+ *   • 2 concurrent requests
+ *   • 50 ms inter-batch delay
+ *   • Standard browser User-Agent / Referer headers
+ *
+ * Usage:
+ *   const downloader = new OfflineTileDownloader({
+ *     baseMap:    'topo',
+ *     extent3857: [minX, minY, maxX, maxY],   // EPSG:3857
+ *     minZoom:    10,
+ *     maxZoom:    15,
+ *     onProgress: (s) => console.log(s),
+ *   });
+ *   await downloader.start();
+ *   downloader.cancel();   // any time
+ */
+
+// ============================================================================
+// Base-map URL templates
+// ============================================================================
+
+/**
+ * Tile URL templates for base maps that may be downloaded for offline use.
+ *
+ * The SW recognises these hosts in `getTileCacheName()` and routes them to
+ * the matching `tiles-*-vN` cache. If you add a new entry here, also add
+ * the host to the SW's classifier or the tiles will not be cached.
+ */
+export const BASEMAP_TEMPLATES = {
+  topo: {
+    url: 'https://a.tile.opentopomap.org/{z}/{x}/{y}.png',
+    label: 'Topographic',
+    maxZoom: 17,
+    cacheKey: 'tiles-topo',
+  },
+  osm: {
+    url: 'https://a.tile.openstreetmap.org/{z}/{x}/{y}.png',
+    label: 'OpenStreetMap',
+    maxZoom: 19,
+    cacheKey: 'tiles-osm',
+  },
+};
+
+// Approximate bytes per raster tile — used for storage estimates.
+export const AVG_TILE_BYTES = 30 * 1024;
+
+// ============================================================================
+// Tile coordinate math (Web Mercator XYZ scheme)
+// ============================================================================
+
+const ORIGIN_SHIFT = 2 * Math.PI * 6378137 / 2; // 20037508.342789244
+
+/** Convert Web Mercator metres → (lon, lat) in degrees. */
+function metersToLonLat(x, y) {
+  const lon = (x / ORIGIN_SHIFT) * 180;
+  let lat = (y / ORIGIN_SHIFT) * 180;
+  lat = 180 / Math.PI * (2 * Math.atan(Math.exp(lat * Math.PI / 180)) - Math.PI / 2);
+  return [lon, lat];
+}
+
+/** Tile (x, y) in XYZ scheme for a given lon/lat at zoom z. */
+function lonLatToTile(lon, lat, z) {
+  const n = Math.pow(2, z);
+  const x = Math.floor((lon + 180) / 360 * n);
+  const latRad = lat * Math.PI / 180;
+  const y = Math.floor(
+    (1 - Math.log(Math.tan(latRad) + 1 / Math.cos(latRad)) / Math.PI) / 2 * n
+  );
+  return { x, y };
+}
+
+/** Tile range covering an EPSG:3857 extent at a given zoom level. */
+export function tileRangeForExtent(extent3857, z) {
+  const [minX, minY, maxX, maxY] = extent3857;
+  const [minLon, minLat] = metersToLonLat(minX, minY);
+  const [maxLon, maxLat] = metersToLonLat(maxX, maxY);
+
+  const tl = lonLatToTile(minLon, maxLat, z); // top-left in XYZ (NW)
+  const br = lonLatToTile(maxLon, minLat, z); // bottom-right (SE)
+
+  const n = Math.pow(2, z);
+  const minTileX = Math.max(0, Math.min(tl.x, br.x));
+  const maxTileX = Math.min(n - 1, Math.max(tl.x, br.x));
+  const minTileY = Math.max(0, Math.min(tl.y, br.y));
+  const maxTileY = Math.min(n - 1, Math.max(tl.y, br.y));
+
+  return {
+    z,
+    minX: minTileX, maxX: maxTileX,
+    minY: minTileY, maxY: maxTileY,
+    count: (maxTileX - minTileX + 1) * (maxTileY - minTileY + 1),
+  };
+}
+
+/** Total tile count for an extent across a zoom range (inclusive). */
+export function countTiles(extent3857, minZ, maxZ) {
+  let total = 0;
+  for (let z = minZ; z <= maxZ; z++) {
+    total += tileRangeForExtent(extent3857, z).count;
+  }
+  return total;
+}
+
+/**
+ * Enumerate every tile in an extent across a zoom range.
+ * Returns an array of { z, x, y } objects. For very large ranges this can be
+ * large — the caller is expected to validate the count first.
+ */
+export function enumerateTiles(extent3857, minZ, maxZ) {
+  const out = [];
+  for (let z = minZ; z <= maxZ; z++) {
+    const r = tileRangeForExtent(extent3857, z);
+    for (let x = r.minX; x <= r.maxX; x++) {
+      for (let y = r.minY; y <= r.maxY; y++) {
+        out.push({ z, x, y });
+      }
+    }
+  }
+  return out;
+}
+
+/**
+ * Format a tile URL for a given coordinate using a {z}/{x}/{y} template.
+ */
+export function formatTileUrl(template, { z, x, y }) {
+  return template
+    .replace('{z}', z)
+    .replace('{x}', x)
+    .replace('{y}', y);
+}
+
+// ============================================================================
+// OfflineTileDownloader
+// ============================================================================
+
+/**
+ * Concurrent, throttled tile downloader. Issues `fetch()` per tile; the
+ * service worker handles caching transparently.
+ *
+ * Events via `onProgress` callback:
+ *   { phase: 'running' | 'done' | 'cancelled' | 'error',
+ *     done, total, ok, failed, cached,
+ *     elapsedMs, etaMs }
+ */
+export class OfflineTileDownloader {
+  constructor({
+    baseMap,             // 'topo' | 'osm'
+    extent3857,          // [minX, minY, maxX, maxY]
+    minZoom,
+    maxZoom,
+    concurrency = 2,     // OSM ToS-friendly default
+    interBatchDelayMs = 50,
+    onProgress = () => {},
+  }) {
+    const tpl = BASEMAP_TEMPLATES[baseMap];
+    if (!tpl) throw new Error(`Unknown base map: ${baseMap}`);
+    if (maxZoom > tpl.maxZoom) {
+      console.warn(`[OfflineTiles] ${baseMap}: maxZoom ${maxZoom} > supported ${tpl.maxZoom}; clamping`);
+      maxZoom = tpl.maxZoom;
+    }
+
+    this.baseMap          = baseMap;
+    this.template         = tpl.url;
+    this.extent           = extent3857;
+    this.minZoom          = minZoom;
+    this.maxZoom          = maxZoom;
+    this.concurrency      = Math.max(1, Math.min(concurrency, 6));
+    this.interBatchDelayMs = interBatchDelayMs;
+    this.onProgress       = onProgress;
+
+    this._abortCtrl       = null;
+    this._cancelled       = false;
+  }
+
+  /**
+   * Begin downloading. Returns a Promise that resolves with the final stats
+   * when complete, or when cancelled.
+   */
+  async start() {
+    if (this._abortCtrl) throw new Error('Downloader already started');
+    this._abortCtrl = new AbortController();
+    this._cancelled = false;
+
+    const tiles = enumerateTiles(this.extent, this.minZoom, this.maxZoom);
+    const total = tiles.length;
+    const startedAt = Date.now();
+
+    let done = 0, ok = 0, failed = 0, cached = 0;
+
+    const emit = (phase) => {
+      const elapsedMs = Date.now() - startedAt;
+      const etaMs = done > 0 ? Math.round((elapsedMs / done) * (total - done)) : null;
+      this.onProgress({ phase, done, total, ok, failed, cached, elapsedMs, etaMs });
+    };
+
+    emit('running');
+
+    // Process in chunks of `concurrency`
+    for (let i = 0; i < tiles.length; i += this.concurrency) {
+      if (this._cancelled) break;
+
+      const batch = tiles.slice(i, i + this.concurrency);
+      await Promise.all(batch.map(async (t) => {
+        if (this._cancelled) return;
+        const url = formatTileUrl(this.template, t);
+
+        try {
+          const res = await fetch(url, {
+            signal: this._abortCtrl.signal,
+            // Hint the SW that this is a passive prefetch
+            cache: 'default',
+          });
+
+          if (res.ok) {
+            ok++;
+            // Detect "served from SW cache" via headers — not reliable across
+            // implementations, so we just count all 200s as ok. Reading the body
+            // (or cancelling it) lets the browser GC the response promptly.
+            if (res.body) res.body.cancel().catch(() => {});
+          } else if (res.status === 408) {
+            // Our SW returns 408 when offline AND nothing cached. Treat as failed.
+            failed++;
+          } else {
+            failed++;
+          }
+        } catch (err) {
+          if (err.name === 'AbortError') {
+            // Cancellation — don't count
+          } else {
+            failed++;
+          }
+        }
+        done++;
+      }));
+
+      emit('running');
+
+      if (this.interBatchDelayMs > 0 && i + this.concurrency < tiles.length) {
+        await new Promise((r) => setTimeout(r, this.interBatchDelayMs));
+      }
+    }
+
+    emit(this._cancelled ? 'cancelled' : 'done');
+
+    return {
+      phase:    this._cancelled ? 'cancelled' : 'done',
+      done, total, ok, failed, cached,
+      elapsedMs: Date.now() - startedAt,
+    };
+  }
+
+  /**
+   * Cancel an in-flight download. Resolves on the next batch boundary.
+   */
+  cancel() {
+    this._cancelled = true;
+    if (this._abortCtrl) this._abortCtrl.abort();
+  }
+}
+
+// ============================================================================
+// Predefined extents
+// ============================================================================
+
+/**
+ * Whole-of-Ghana bounding box in EPSG:3857.
+ * Approximate: -3.3°W → 1.2°E, 4.5°N → 11.2°N.
+ */
+export const GHANA_EXTENT_3857 = (() => {
+  const lonLatToMeters = (lon, lat) => {
+    const x = lon * ORIGIN_SHIFT / 180;
+    const y = Math.log(Math.tan((90 + lat) * Math.PI / 360)) / (Math.PI / 180);
+    return [x, y * ORIGIN_SHIFT / 180];
+  };
+  const sw = lonLatToMeters(-3.3, 4.5);
+  const ne = lonLatToMeters(1.2, 11.2);
+  return [sw[0], sw[1], ne[0], ne[1]];
+})();
+
+// Useful for size estimates
+export function estimatedSizeBytes(tileCount) {
+  return tileCount * AVG_TILE_BYTES;
+}
--- a/src/pdf-export.js
+++ b/src/pdf-export.js
@ -0,0 +1,157 @@
+/**
+ * PDF Export Module
+ *
+ * Generates branded PDF reports from analysis data.
+ * Uses jspdf + jspdf-autotable, loaded on demand via dynamic import
+ * from the calling code so the library is only fetched when needed.
+ *
+ * Usage:
+ *   import { exportAnalysisPDF } from '../pdf-export.js';
+ *   await exportAnalysisPDF({ title: 'Circle Analysis', rows: [...] });
+ */
+
+import { jsPDF } from 'jspdf';
+import { applyPlugin } from 'jspdf-autotable';
+
+applyPlugin(jsPDF);
+
+// Cached logo data URL — fetched once, reused for subsequent exports
+let _logoDataUrl = null;
+
+/**
+ * Load the LUSPA logo, draw it onto a canvas to flatten alpha and
+ * produce a clean JPEG data URL that jsPDF can embed reliably.
+ * Caches the result so subsequent calls are instant.
+ */
+async function getLogoDataUrl() {
+  if (_logoDataUrl) return _logoDataUrl;
+
+  try {
+    const img = new Image();
+    img.crossOrigin = 'anonymous';
+
+    await new Promise((resolve, reject) => {
+      img.onload = resolve;
+      img.onerror = reject;
+      img.src = './icons/luspa-pdf.jpg';
+    });
+
+    // Draw onto a canvas to get a reliable JPEG data URL
+    const canvas = document.createElement('canvas');
+    canvas.width = img.naturalWidth;
+    canvas.height = img.naturalHeight;
+    const ctx = canvas.getContext('2d');
+    // White background to flatten any remaining alpha
+    ctx.fillStyle = '#ffffff';
+    ctx.fillRect(0, 0, canvas.width, canvas.height);
+    ctx.drawImage(img, 0, 0);
+
+    _logoDataUrl = canvas.toDataURL('image/jpeg', 0.92);
+    return _logoDataUrl;
+  } catch (err) {
+    console.warn('[PDF] Could not load logo:', err);
+    return null;
+  }
+}
+
+/**
+ * Generate and open a branded PDF report.
+ *
+ * @param {Object} options
+ * @param {string} options.title - Report title (e.g. "Circle Analysis")
+ * @param {Array<{label: string, value: string}>} options.rows - Table data
+ */
+export async function exportAnalysisPDF({ title, rows }) {
+  const doc = new jsPDF({ orientation: 'portrait', unit: 'mm', format: 'a4' });
+  const pageWidth = doc.internal.pageSize.getWidth();
+
+  // Brand colours
+  const navy = [30, 26, 75];  // #1e1a4b
+
+  // ---- Logo ----
+  const logo = await getLogoDataUrl();
+  const logoSize = 28;
+  const marginLeft = 14;
+  let cursorY = 14;
+
+  if (logo) {
+    doc.addImage(logo, 'JPEG', marginLeft, cursorY, logoSize, logoSize);
+  }
+
+  // ---- Header text (next to logo) ----
+  const textX = marginLeft + logoSize + 6;
+
+  doc.setFont('helvetica', 'bold');
+  doc.setFontSize(18);
+  doc.setTextColor(...navy);
+  doc.text('LUPMIS', textX, cursorY + 11);
+
+  doc.setFont('helvetica', 'normal');
+  doc.setFontSize(12);
+  doc.text(title, textX, cursorY + 19);
+
+  // ---- Date / time ----
+  const now = new Date();
+  const dateStr = now.toLocaleDateString(undefined, {
+    year: 'numeric', month: 'long', day: 'numeric',
+  });
+  const timeStr = now.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
+
+  doc.setFontSize(9);
+  doc.setTextColor(120, 120, 120);
+  doc.text(`${dateStr}  ${timeStr}`, pageWidth - marginLeft, cursorY + 11, { align: 'right' });
+
+  // ---- Divider line ----
+  cursorY += logoSize + 6;
+  doc.setDrawColor(...navy);
+  doc.setLineWidth(0.5);
+  doc.line(marginLeft, cursorY, pageWidth - marginLeft, cursorY);
+  cursorY += 6;
+
+  // ---- Analysis table ----
+  const tableBody = rows.map(r => [r.label, r.value]);
+
+  doc.autoTable({
+    startY: cursorY,
+    head: [['Property', 'Value']],
+    body: tableBody,
+    margin: { left: marginLeft, right: marginLeft },
+    styles: {
+      font: 'helvetica',
+      fontSize: 10,
+      cellPadding: 4,
+    },
+    headStyles: {
+      fillColor: navy,
+      textColor: [255, 255, 255],
+      fontStyle: 'bold',
+    },
+    alternateRowStyles: {
+      fillColor: [245, 245, 250],
+    },
+    columnStyles: {
+      0: { fontStyle: 'bold', cellWidth: 50 },
+    },
+  });
+
+  // ---- Footer ----
+  const finalY = doc.lastAutoTable.finalY + 10;
+  doc.setFontSize(8);
+  doc.setTextColor(160, 160, 160);
+  doc.text('Generated by LUPMIS2 Land Use Planning & Management Information System', marginLeft, finalY);
+
+  // ---- Open in browser ----
+  const blob = doc.output('blob');
+  const url = URL.createObjectURL(blob);
+
+  const win = window.open(url, '_blank');
+  if (!win) {
+    // Popup blocked (mobile) — fall back to download
+    const a = document.createElement('a');
+    a.href = url;
+    a.download = `${title.replace(/\s+/g, '_')}_${now.toISOString().slice(0, 10)}.pdf`;
+    document.body.appendChild(a);
+    a.click();
+    document.body.removeChild(a);
+  }
+}
--- a/src/pwa.js
+++ b/src/pwa.js
@ -276,6 +276,158 @@ export function clearUserCaches() {
  });
 }

+/**
+ * Get the Service Worker we can postMessage to. Resolves with:
+ *   • `navigator.serviceWorker.controller` if it's already in control of the
+ *     page (fastest path), or
+ *   • `registration.active` once `navigator.serviceWorker.ready` resolves
+ *     (covers the first-load case before the SW has claimed the page).
+ *
+ * Rejects after `timeoutMs` if no SW becomes available — which would only
+ * happen in a private/incognito context, an unsupported browser, or when
+ * registration genuinely failed.
+ *
+ * @param {{ timeoutMs?: number }} [opts]
+ * @returns {Promise<ServiceWorker>}
+ */
+export async function getActiveServiceWorker({ timeoutMs = 10000 } = {}) {
+  if (!('serviceWorker' in navigator)) {
+    throw new Error('Service Workers not supported in this browser');
+  }
+
+  // Fastest path — page is already SW-controlled
+  if (navigator.serviceWorker.controller) {
+    return navigator.serviceWorker.controller;
+  }
+
+  // Otherwise wait for the registration to become ready (active SW exists
+  // for this scope, even if it hasn't claimed THIS page yet)
+  const ready = navigator.serviceWorker.ready;
+  const timeout = new Promise((_, reject) =>
+    setTimeout(() => reject(new Error('Service-worker readiness timeout')), timeoutMs)
+  );
+
+  const registration = await Promise.race([ready, timeout]);
+
+  // The controller may have appeared while we were waiting; otherwise use
+  // the registration's active worker (we can still postMessage to it — caches
+  // are shared across the origin)
+  const sw = navigator.serviceWorker.controller || registration.active;
+  if (!sw) {
+    throw new Error('No active service worker available');
+  }
+  return sw;
+}
+
+/**
+ * Subscribe to controller-change events. The callback fires whenever a new
+ * Service Worker takes control of the page (e.g. after an SW update or first
+ * activation on initial load). Useful for re-querying SW-backed state once
+ * the SW has actually taken over.
+ *
+ * @param {() => void} callback
+ * @returns {() => void} unsubscribe function
+ */
+export function onServiceWorkerControllerChange(callback) {
+  if (!('serviceWorker' in navigator)) return () => {};
+  const handler = () => {
+    try { callback(); } catch (e) { console.error('[PWA] controllerchange handler error:', e); }
+  };
+  navigator.serviceWorker.addEventListener('controllerchange', handler);
+  return () => navigator.serviceWorker.removeEventListener('controllerchange', handler);
+}
+
+/**
+ * Send a message to the service worker and wait for a single reply with the
+ * given response type. Waits for the SW to become available if it isn't yet.
+ * Resolves with the reply payload, or rejects after a timeout.
+ *
+ * @template T
+ * @param {string} requestType   - Message type to send (e.g. 'GET_TILE_STATS')
+ * @param {string} responseType  - Message type expected back (e.g. 'TILE_STATS')
+ * @param {Object} [extra={}]    - Extra fields merged into the outgoing message
+ * @param {number} [timeoutMs=5000]   Reply timeout (after the SW is available)
+ * @param {number} [readyTimeoutMs=10000] Timeout for the SW to be available
+ * @returns {Promise<T>}
+ */
+async function requestFromServiceWorker(requestType, responseType, extra = {}, timeoutMs = 5000, readyTimeoutMs = 10000) {
+  const sw = await getActiveServiceWorker({ timeoutMs: readyTimeoutMs });
+
+  return new Promise((resolve, reject) => {
+    const channel = new MessageChannel();
+    const timer = setTimeout(() => {
+      channel.port1.close();
+      reject(new Error(`Service-worker reply "${responseType}" timed out`));
+    }, timeoutMs);
+
+    channel.port1.onmessage = (event) => {
+      if (event.data?.type === responseType) {
+        clearTimeout(timer);
+        channel.port1.close();
+        const { type, ...rest } = event.data;
+        resolve(rest);
+      }
+    };
+
+    sw.postMessage({ type: requestType, ...extra }, [channel.port2]);
+  });
+}
+
+/**
+ * Get statistics about tiles cached locally on this device, broken down by
+ * provider. Waits up to `readyTimeoutMs` for the service worker to become
+ * available. Returns null only if the SW genuinely cannot be reached
+ * (private mode, registration failure, or timeout).
+ *
+ * @returns {Promise<{
+ *   totals: { count: number, estBytes: number },
+ *   byProvider: Array<{ key: string, label: string, count: number, limit: number, estBytes: number }>
+ * } | null>}
+ */
+export async function getTileCacheStats() {
+  try {
+    const reply = await requestFromServiceWorker('GET_TILE_STATS', 'TILE_STATS');
+    return reply.stats;
+  } catch (err) {
+    console.warn('[PWA] getTileCacheStats failed:', err);
+    return null;
+  }
+}
+
+/**
+ * Delete every cached tile from this device. Doesn't touch the app shell,
+ * modules, or API caches — only the per-provider tile buckets.
+ * Waits for the SW to be available before sending the request.
+ *
+ * @returns {Promise<boolean>} true if the request was acknowledged
+ */
+export async function clearTileCaches() {
+  try {
+    await requestFromServiceWorker('CLEAR_TILE_CACHES', 'TILE_CACHES_CLEARED');
+    return true;
+  } catch (err) {
+    console.warn('[PWA] clearTileCaches failed:', err);
+    return false;
+  }
+}
+
+/**
+ * Get total disk used by this origin (Cache API + IndexedDB + OPFS).
+ * Returns null if the Storage API is not available.
+ *
+ * @returns {Promise<{ usage: number, quota: number } | null>}
+ */
+export async function getStorageEstimate() {
+  if (!navigator.storage?.estimate) return null;
+  try {
+    const { usage, quota } = await navigator.storage.estimate();
+    return { usage: usage || 0, quota: quota || 0 };
+  } catch (err) {
+    console.warn('[PWA] getStorageEstimate failed:', err);
+    return null;
+  }
+}
+
 // ============================================================================
 // Auto-initialization
 // ============================================================================
@ -313,5 +465,10 @@ export default {
  applyUpdate,
  postToServiceWorker,
  cacheModules,
-  clearUserCaches
+  clearUserCaches,
+  getTileCacheStats,
+  clearTileCaches,
+  getStorageEstimate,
+  getActiveServiceWorker,
+  onServiceWorkerControllerChange,
 };
--- a/src/remotedb.js
+++ b/src/remotedb.js
@ -21,13 +21,89 @@ const API_CREDENTIALS = {
  api_token: '1c46538c712e9b5b'
 };

+// ============================================================================
+// Server Reachability
+// ============================================================================
+
+/** Default timeout for API requests (ms) */
+const REQUEST_TIMEOUT = 30_000;
+
+/** Timeout for the fast reachability probe (ms) */
+const PING_TIMEOUT = 5_000;
+
+/** Cached result of the last reachability check */
+let _serverReachable = null;
+
+/**
+ * Quick probe to determine if the API server is responding.
+ * Sends a small POST to a lightweight endpoint with a short timeout.
+ * The result is cached so subsequent calls within the same page load
+ * return immediately.
+ *
+ * @param {boolean} [force=false] - Re-check even if a cached result exists
+ * @returns {Promise<boolean>} true if the server responded in time
+ */
+export async function checkServerReachable(force = false) {
+  if (_serverReachable !== null && !force) return _serverReachable;
+
+  const controller = new AbortController();
+  const timer = setTimeout(() => controller.abort(), PING_TIMEOUT);
+
+  try {
+    const response = await fetch(`${API_BASE}/get_layers.php`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json', 'Accept': 'application/json' },
+      body: JSON.stringify(API_CREDENTIALS),
+      signal: controller.signal,
+    });
+    _serverReachable = response.ok;
+  } catch {
+    _serverReachable = false;
+  } finally {
+    clearTimeout(timer);
+  }
+
+  console.log('[RemoteDB] Server reachable:', _serverReachable);
+  return _serverReachable;
+}
+
+/**
+ * Returns the cached server-reachability flag (synchronous).
+ * Returns null if checkServerReachable() has not been called yet.
+ * @returns {boolean|null}
+ */
+export function isServerReachable() {
+  return _serverReachable;
+}
+
 // ============================================================================
 // Core Request Helpers
 // ============================================================================

+/**
+ * Create an AbortController that auto-aborts after `ms` milliseconds.
+ * If the caller already supplied a signal in `options`, it is combined
+ * so that either the caller's abort or the timeout will cancel the request.
+ */
+function withTimeout(options, ms = REQUEST_TIMEOUT) {
+  const controller = new AbortController();
+  const timer = setTimeout(() => controller.abort(), ms);
+
+  // If the caller provided their own signal, chain it
+  if (options.signal) {
+    options.signal.addEventListener('abort', () => controller.abort());
+  }
+
+  return {
+    signal: controller.signal,
+    clear: () => clearTimeout(timer),
+  };
+}
+
 /**
 * Perform a GET request to the remote API.
 * Credentials are sent as URL query parameters.
+ * Automatically times out after REQUEST_TIMEOUT ms.
 *
 * @param {string} endpoint - API endpoint filename (e.g. 'get_district_boundary.php')
 * @param {Object} [params={}] - Additional query parameters
@ -45,13 +121,15 @@ export async function remoteGet(endpoint, params = {}, options = {}) {

  console.log('[RemoteDB] GET', url.toString());

+  const timeout = withTimeout(options);
  try {
    const response = await fetch(url.toString(), {
      method: 'GET',
      headers: {
        'Accept': 'application/json'
      },
-      ...options
+      ...options,
+      signal: timeout.signal,
    });

    if (!response.ok) {
@ -63,14 +141,21 @@ export async function remoteGet(endpoint, params = {}, options = {}) {
    return data;

  } catch (error) {
+    if (error.name === 'AbortError') {
+      console.error('[RemoteDB] GET timed out:', endpoint);
+      throw new Error(`Request timed out: ${endpoint}`);
+    }
    console.error('[RemoteDB] GET failed:', endpoint, error);
    throw error;
+  } finally {
+    timeout.clear();
  }
 }

 /**
 * Perform a POST request to the remote API.
 * Credentials are included in the JSON body.
+ * Automatically times out after REQUEST_TIMEOUT ms.
 *
 * @param {string} endpoint - API endpoint filename (e.g. 'some_endpoint.php')
 * @param {Object} [body={}] - Request payload (credentials are merged in)
@ -84,6 +169,7 @@ export async function remotePost(endpoint, body = {}, options = {}) {

  console.log('[RemoteDB] POST', url);

+  const timeout = withTimeout(options);
  try {
    const response = await fetch(url, {
      method: 'POST',
@ -92,7 +178,8 @@ export async function remotePost(endpoint, body = {}, options = {}) {
        'Accept': 'application/json'
      },
      body: JSON.stringify(payload),
-      ...options
+      ...options,
+      signal: timeout.signal,
    });

    if (!response.ok) {
@ -104,8 +191,14 @@ export async function remotePost(endpoint, body = {}, options = {}) {
    return data;

  } catch (error) {
+    if (error.name === 'AbortError') {
+      console.error('[RemoteDB] POST timed out:', endpoint);
+      throw new Error(`Request timed out: ${endpoint}`);
+    }
    console.error('[RemoteDB] POST failed:', endpoint, error);
    throw error;
+  } finally {
+    timeout.clear();
  }
 }

@ -170,16 +263,50 @@ export async function getBuildingFootprints() {
  return remotePost('get_all_footprint_per_district.php');
 }

+/**
+ * Fetch the Contours hillshade elevation layer from the server.
+ *
+ * Source: table `contours_hillshade` in the local PostgreSQL `public` schema
+ * (imported from OpenTopography's viz.hh_hillshade).
+ *
+ * Expected response:
+ * { success: true, data: [{ id, elevation, geom: "LINESTRING(...)" | "MULTILINESTRING(...)" | "POLYGON(...)", ... }, ...] }
+ *
+ * @returns {Promise<Object>} Contours hillshade list
+ */
+export async function getContoursHillshade() {
+  return remotePost('get_contours_hillshade.php');
+}
+
+/**
+ * Fetch the OSM roads layer from the server.
+ *
+ * Source: table `pi_osm_roads` in the local PostgreSQL `public` schema
+ * (imported from OpenStreetMap road network for the district).
+ *
+ * Expected response:
+ * { success: true, data: [{ id, ..., geom: "LINESTRING(...)" | "MULTILINESTRING(...)", ... }, ...] }
+ *
+ * @returns {Promise<Object>} OSM roads list
+ */
+export async function getOSMRoads() {
+  return remotePost('get_osm_roads.php');
+}
+
 // ============================================================================
 // Exports
 // ============================================================================

 export default {
+  checkServerReachable,
+  isServerReachable,
  remoteGet,
  remotePost,
  getDistrictBoundary,
  getLayers,
  getDistrictParcels,
  getCollectorZones,
-  getBuildingFootprints
+  getBuildingFootprints,
+  getContoursHillshade,
+  getOSMRoads,
 };
--- a/src/toast.js
+++ b/src/toast.js
@ -0,0 +1,98 @@
+/**
+ * Lightweight toast notification system.
+ *
+ * Usage:
+ *   import { showToast } from '../toast.js';
+ *
+ *   showToast('Something went wrong', 'error');
+ *   showToast('Merge successful!', 'success');
+ *   showToast('Select two adjacent polygons', 'info');
+ */
+
+// ── Palette ──────────────────────────────────────────────────────────────────
+
+const THEMES = {
+  success: { bg: '#10b981', icon: '\u2705' },  // green
+  error:   { bg: '#ef4444', icon: '\u274c' },  // red
+  warning: { bg: '#f59e0b', icon: '\u26a0\ufe0f' },  // amber
+  info:    { bg: '#0ea5e9', icon: '\u2139\ufe0f' },  // cyan
+};
+
+// ── Container (created once, appended to <body>) ────────────────────────────
+
+let container = null;
+
+function ensureContainer() {
+  if (container) return container;
+  container = document.createElement('div');
+  container.style.cssText = `
+    position: fixed;
+    top: 16px;
+    left: 50%;
+    transform: translateX(-50%);
+    z-index: 10000;
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    gap: 8px;
+    pointer-events: none;
+  `;
+  document.body.appendChild(container);
+  return container;
+}
+
+// ── Public API ──────────────────────────────────────────────────────────────
+
+/**
+ * Display a toast notification.
+ *
+ * @param {string} message  Plain-text message to show.
+ * @param {'success'|'error'|'warning'|'info'} [type='info']
+ * @param {number} [duration=4000]  Auto-dismiss time in ms.
+ */
+export function showToast(message, type = 'info', duration = 4000) {
+  const parent = ensureContainer();
+  const theme = THEMES[type] || THEMES.info;
+
+  const el = document.createElement('div');
+  el.style.cssText = `
+    background: ${theme.bg};
+    color: #fff;
+    padding: 10px 18px;
+    border-radius: 8px;
+    font-family: var(--font-body, 'Exo', sans-serif);
+    font-size: 13px;
+    font-weight: 600;
+    box-shadow: 0 4px 12px rgba(0,0,0,0.25);
+    pointer-events: auto;
+    cursor: pointer;
+    opacity: 0;
+    transition: opacity 0.25s ease, transform 0.25s ease;
+    transform: translateY(-8px);
+    max-width: 420px;
+    text-align: center;
+    line-height: 1.4;
+  `;
+  el.textContent = `${theme.icon}  ${message}`;
+
+  parent.appendChild(el);
+
+  // Animate in
+  requestAnimationFrame(() => {
+    el.style.opacity = '1';
+    el.style.transform = 'translateY(0)';
+  });
+
+  // Dismiss helper
+  const dismiss = () => {
+    el.style.opacity = '0';
+    el.style.transform = 'translateY(-8px)';
+    setTimeout(() => el.remove(), 300);
+  };
+
+  // Click to dismiss early
+  el.addEventListener('click', dismiss);
+
+  // Auto-dismiss
+  setTimeout(dismiss, duration);
+}
--- a/src/units.js
+++ b/src/units.js
@ -0,0 +1,123 @@
+/**
+ * Measurement unit formatting — Metric / Imperial.
+ *
+ * The active system is persisted in localStorage('measurement-system').
+ * Every formatter reads the current setting so the UI updates immediately
+ * after the user flips the toggle.
+ *
+ * All input values are in metres (length) or square metres (area).
+ */
+
+// ── Conversion constants ────────────────────────────────────────────────────
+const M_TO_FT   = 3.28084;
+const M_TO_MI   = 0.000621371;
+const SQM_TO_SQFT = 10.7639;
+const SQM_TO_ACRE = 0.000247105;
+const SQM_TO_SQMI = 3.861e-7;
+
+// ── System accessor ─────────────────────────────────────────────────────────
+
+/** @returns {'metric'|'imperial'} */
+export function getSystem() {
+  return localStorage.getItem('measurement-system') || 'metric';
+}
+
+// ── Length / distance ───────────────────────────────────────────────────────
+
+/**
+ * Format a length value (in metres) for display.
+ * Metric:   m / km
+ * Imperial: ft / mi
+ */
+export function formatLength(metres) {
+  if (getSystem() === 'imperial') {
+    const ft = metres * M_TO_FT;
+    if (ft >= 5280) {
+      return (Math.round(metres * M_TO_MI * 100) / 100) + ' mi';
+    }
+    return Math.round(ft) + ' ft';
+  }
+  // metric
+  if (metres > 1000) {
+    return (Math.round(metres / 1000 * 100) / 100) + ' km';
+  }
+  return (Math.round(metres * 100) / 100) + ' m';
+}
+
+/**
+ * Format a length with both large and small units (for info popups).
+ * Metric:   "1.23 km  (1,230 m)"   or   "456 m"
+ * Imperial: "1.23 mi  (6,494 ft)"   or   "456 ft"
+ */
+export function formatLengthFull(metres) {
+  if (getSystem() === 'imperial') {
+    const ft = metres * M_TO_FT;
+    const mi = metres * M_TO_MI;
+    if (ft >= 5280) {
+      return `${mi.toFixed(2)} mi  (${ft.toLocaleString('en', { maximumFractionDigits: 0 })} ft)`;
+    }
+    return `${ft.toLocaleString('en', { maximumFractionDigits: 1 })} ft`;
+  }
+  if (metres >= 1000) {
+    return `${(metres / 1000).toFixed(2)} km  (${metres.toLocaleString('en', { maximumFractionDigits: 0 })} m)`;
+  }
+  return `${metres.toLocaleString('en', { maximumFractionDigits: 1 })} m`;
+}
+
+// ── Area ────────────────────────────────────────────────────────────────────
+
+/**
+ * Format an area value (in square metres) for display.
+ * Metric:   m² / km²
+ * Imperial: ft² / acres / mi²
+ */
+export function formatArea(sqMetres) {
+  if (getSystem() === 'imperial') {
+    const acres = sqMetres * SQM_TO_ACRE;
+    if (acres >= 640) {
+      return (Math.round(sqMetres * SQM_TO_SQMI * 100) / 100) + ' mi²';
+    }
+    if (acres >= 1) {
+      return (Math.round(acres * 100) / 100) + ' acres';
+    }
+    return Math.round(sqMetres * SQM_TO_SQFT).toLocaleString('en') + ' ft²';
+  }
+  // metric
+  if (sqMetres > 1000000) {
+    return (Math.round(sqMetres / 1000000 * 100) / 100) + ' km²';
+  }
+  return (Math.round(sqMetres * 100) / 100) + ' m²';
+}
+
+/**
+ * Format an area with both large and small units (for info popups).
+ * Metric:   "1.23 km²  (1,230,000 m²)"   or   "456 m²"
+ * Imperial: "1.23 mi²  (787 acres)"   or   "2.5 acres"   or   "456 ft²"
+ */
+export function formatAreaFull(sqMetres) {
+  if (getSystem() === 'imperial') {
+    const sqft = sqMetres * SQM_TO_SQFT;
+    const acres = sqMetres * SQM_TO_ACRE;
+    const sqmi = sqMetres * SQM_TO_SQMI;
+    if (acres >= 640) {
+      return `${sqmi.toFixed(2)} mi²  (${acres.toLocaleString('en', { maximumFractionDigits: 0 })} acres)`;
+    }
+    if (acres >= 1) {
+      return `${acres.toLocaleString('en', { maximumFractionDigits: 1 })} acres  (${sqft.toLocaleString('en', { maximumFractionDigits: 0 })} ft²)`;
+    }
+    return `${sqft.toLocaleString('en', { maximumFractionDigits: 0 })} ft²`;
+  }
+  if (sqMetres > 1000000) {
+    return `${(sqMetres / 1000000).toFixed(2)} km²  (${sqMetres.toLocaleString('en', { maximumFractionDigits: 0 })} m²)`;
+  }
+  return `${sqMetres.toLocaleString('en', { maximumFractionDigits: 0 })} m²`;
+}
+
+// ── Circle helper ───────────────────────────────────────────────────────────
+
+/**
+ * Format the area of a circle given its radius (in metres).
+ */
+export function formatCircleExtent(radiusMetres) {
+  return formatArea(Math.PI * radiusMetres * radiusMetres);
+}
--- a/vite.config.js
+++ b/vite.config.js
@ -34,12 +34,25 @@ export default defineConfig({
    // Target modern browsers that support OPFS
    target: 'esnext',

+    // Raise the chunk-size warning threshold.
+    // Rationale: the two largest chunks are unavoidable —
+    //   • openlayers (~535 kB / ~152 kB gzipped) — the OL library itself,
+    //     used app-wide; further splitting just creates more HTTP round-trips
+    //   • sqlite3.wasm (~856 kB) — a runtime WASM binary, not a JS chunk;
+    //     code-splitting does not apply
+    // 900 kB silences the noise without hiding genuine regressions.
+    chunkSizeWarningLimit: 900,
+
    rollupOptions: {
      output: {
        manualChunks(id) {
          if (id.includes('node_modules/ol/')) return 'openlayers';
          if (id.includes('node_modules/ol-ext/')) return 'ol-ext';
          if (id.includes('node_modules/bootstrap/')) return 'bootstrap';
+          // shpjs (+ its jszip dependency) — dynamically imported at runtime,
+          // so this chunk is only fetched when the user imports a shapefile.
+          if (id.includes('node_modules/shpjs/') || id.includes('node_modules/jszip/')) return 'shpjs';
+          if (id.includes('node_modules/jspdf')) return 'jspdf';
        },
      },
    },
				`@ -1 +0,0 @@`
				`Place PWA icons here (icon-72.png, icon-96.png, icon-128.png, icon-144.png, icon-152.png, icon-192.png, icon-384.png, icon-512.png)`