fix: recover hidden areas from map canvas

frontend/src/components/maps/LocationMapCanvas.jsx

@@ -22,7 +22,9 @@ export default function LocationMapCanvas({
   svgRef,
   dragState,
   editingLocked = false,
+  hiddenAreaCount = 0,
   onShowZones,
+  onShowHiddenAreas,
   setDragState,
   setSelectedObjectKey,
   remember,
@@ -35,6 +37,9 @@ export default function LocationMapCanvas({
     ? objects.filter((object) => object.visible).length
     : 0;
   const hasNoVisibleObjects = objects.length > 0 && filters.showZones && visibleObjectCount === 0;
+  const canRecoverHiddenAreas =
+    mode === "edit" && hasNoVisibleObjects && hiddenAreaCount > 0 && typeof onShowHiddenAreas === "function";
+  const hasEmptyCanvasAction = hiddenByZonesLayer || canRecoverHiddenAreas;
   const emptyCanvasMessage = objects.length === 0
     ? "No map areas yet"
     : hiddenByZonesLayer
@@ -155,6 +160,11 @@ export default function LocationMapCanvas({
     onShowZones?.();
   };
 
+  const handleShowHiddenAreas = (event) => {
+    event.stopPropagation();
+    onShowHiddenAreas?.();
+  };
+
   const clearSelection = () => {
     if (suppressPanClickRef.current) {
       suppressPanClickRef.current = false;
@@ -392,7 +402,7 @@ export default function LocationMapCanvas({
           <div
             className={[
               "location-map-empty-canvas",
-              hiddenByZonesLayer ? "has-action" : "",
+              hasEmptyCanvasAction ? "has-action" : "",
             ].filter(Boolean).join(" ")}
           >
             <span>{emptyCanvasMessage}</span>
@@ -404,6 +414,14 @@ export default function LocationMapCanvas({
               >
                 Show Zones
               </button>
+            ) : canRecoverHiddenAreas ? (
+              <button
+                type="button"
+                onPointerDown={(event) => event.stopPropagation()}
+                onClick={handleShowHiddenAreas}
+              >
+                Show Hidden
+              </button>
             ) : null}
           </div>
         ) : null}

frontend/src/pages/LocationMapManager.jsx

@@ -558,6 +558,7 @@ export default function LocationMapManager() {
               svgRef={svgRef}
               dragState={dragState}
               editingLocked={saving}
+              hiddenAreaCount={hiddenAreaCount}
               setDragState={setDragState}
               setSelectedObjectKey={setSelectedObjectKey}
               remember={remember}
@@ -568,6 +569,7 @@ export default function LocationMapManager() {
                   showZones: true,
                 }))
               }
+              onShowHiddenAreas={handleShowHiddenAreas}
             />
             <LocationMapBottomSheet
               mode={mode}

frontend/tests/location-map-manager.spec.ts

@@ -596,7 +596,7 @@ test("admin selecting an object does not mark a draft dirty until it changes", a
   await expect(page.getByRole("button", { name: "Undo" })).toBeEnabled();
 });
 
-test("admin can recover hidden map areas from the edit sheet", async ({ page }) => {
+test("admin can recover hidden map areas from the empty canvas", async ({ page }) => {
   await mockMapShell(page);
 
   let savedPayload: Record<string, unknown> | null = null;
@@ -655,11 +655,13 @@ test("admin can recover hidden map areas from the edit sheet", async ({ page })
   await expect(page.getByRole("button", { name: "Map area Bakery" })).toHaveCount(0);
   await expect(page.locator(".location-map-sheet-header strong")).toHaveText("Edit Objects");
   await expect(page.getByText("No visible map areas")).toBeVisible();
+  await expect(page.locator(".location-map-empty-canvas").getByRole("button", { name: "Show Hidden" })).toBeVisible();
   await expect(page.getByRole("button", { name: "Show Hidden Areas (1)" })).toBeVisible();
   await expect(page.locator(".location-map-status")).toHaveText("Unsaved Draft");
 
-  await page.getByRole("button", { name: "Show Hidden Areas (1)" }).click();
+  await page.locator(".location-map-empty-canvas").getByRole("button", { name: "Show Hidden" }).click();
   await expect(page.getByRole("button", { name: "Map area Bakery" })).toBeVisible();
+  await expect(page.locator(".location-map-empty-canvas").getByRole("button", { name: "Show Hidden" })).toHaveCount(0);
   await expect(page.getByRole("button", { name: "Show Hidden Areas (1)" })).toHaveCount(0);
 
   await page.getByRole("button", { name: "Save Draft" }).click();