feat: implement comprehensive map editing system with advanced geometry tools, replay management, and project session state modules.

src/uhm/lib/editor/background/backgroundVisibilityStorage.ts

@@ -0,0 +1,59 @@
+import {
+    BACKGROUND_LAYER_OPTIONS,
+    BackgroundLayerVisibility,
+    DEFAULT_BACKGROUND_LAYER_VISIBILITY,
+} from "@/uhm/lib/map/styles/backgroundLayers";
+
+const BACKGROUND_LAYER_VISIBILITY_STORAGE_KEY = "uhm.backgroundLayerVisibility.v2";
+
+export function loadBackgroundLayerVisibilityFromStorage(): BackgroundLayerVisibility {
+    if (typeof window === "undefined") {
+        return { ...DEFAULT_BACKGROUND_LAYER_VISIBILITY };
+    }
+
+    try {
+        const raw = window.localStorage.getItem(BACKGROUND_LAYER_VISIBILITY_STORAGE_KEY);
+        if (!raw) {
+            return { ...DEFAULT_BACKGROUND_LAYER_VISIBILITY };
+        }
+
+        const parsed = JSON.parse(raw) as unknown;
+        const normalized = normalizeBackgroundLayerVisibility(parsed);
+        return normalized || { ...DEFAULT_BACKGROUND_LAYER_VISIBILITY };
+    } catch (err) {
+        console.warn("Load background layer visibility from storage failed", err);
+        return { ...DEFAULT_BACKGROUND_LAYER_VISIBILITY };
+    }
+}
+
+export function persistBackgroundLayerVisibility(visibility: BackgroundLayerVisibility) {
+    if (typeof window === "undefined") return;
+    try {
+        window.localStorage.setItem(
+            BACKGROUND_LAYER_VISIBILITY_STORAGE_KEY,
+            JSON.stringify(visibility)
+        );
+    } catch (err) {
+        console.warn("Persist background layer visibility failed", err);
+    }
+}
+
+function normalizeBackgroundLayerVisibility(raw: unknown): BackgroundLayerVisibility | null {
+    if (!raw || typeof raw !== "object") return null;
+
+    const source = raw as Partial<Record<string, boolean>>;
+
+
+    const next: BackgroundLayerVisibility = {
+        ...DEFAULT_BACKGROUND_LAYER_VISIBILITY,
+    };
+
+    for (const layer of BACKGROUND_LAYER_OPTIONS) {
+        const value = source[layer.id];
+        if (typeof value === "boolean") {
+            next[layer.id] = value;
+        }
+    }
+
+    return next;
+}