refactor(web): folders store (#14305)

* refactor(web): folders store

* use typescript private

web/src/lib/stores/folders.svelte.ts

@@ -0,0 +1,45 @@
+import {
+  getAssetsByOriginalPath,
+  getUniqueOriginalPaths,
+  /**
+   * TODO: Incorrect type
+   */
+  type AssetResponseDto,
+} from '@immich/sdk';
+
+type AssetCache = {
+  [path: string]: AssetResponseDto[];
+};
+
+class FoldersStore {
+  private initialized = false;
+  uniquePaths = $state<string[]>([]);
+  assets = $state<AssetCache>({});
+
+  async fetchUniquePaths() {
+    if (this.initialized) {
+      return;
+    }
+    this.initialized = true;
+
+    const uniquePaths = await getUniqueOriginalPaths();
+    this.uniquePaths.push(...uniquePaths);
+    this.uniquePaths.sort();
+  }
+
+  async fetchAssetsByPath(path: string) {
+    if (this.assets[path]) {
+      return;
+    }
+
+    this.assets[path] = await getAssetsByOriginalPath({ path });
+  }
+
+  clearCache() {
+    this.initialized = false;
+    this.uniquePaths = [];
+    this.assets = {};
+  }
+}
+
+export const foldersStore = new FoldersStore();