feat(library): smart subfolder auto-link and instant handle reconnection

docker/frontend/src/Library.tsx

@@ -20,6 +20,7 @@ import {
   pickFolder,
   readPhotoFile,
   readPhotos,
+  reconnectPhotosForFolders,
   removeFolder,
   renameFolder,
   scanAsked,
@@ -713,6 +714,7 @@ export function Library() {
     async (folder: LibraryFolder) => {
       if (await ensurePermission(folder.handle)) {
         setReady((prev) => new Set(prev).add(folder.name));
+        await reconnectPhotosForFolders(folder.handle);
         await scan(folder);
       } else {
         setNote(t('lib.failed'));

docker/frontend/src/engine/library.ts

@@ -283,6 +283,86 @@ export async function listFolders(): Promise<LibraryFolder[]> {
   }
 }
 
+export async function reconnectPhotosForFolders(
+  newFolderHandle: FileSystemDirectoryHandle
+): Promise<{ reconnectedFolders: number; reconnectedPhotos: number }> {
+  const existingFolders = await listFolders();
+  const allPhotos = (await readPhotos()) ?? [];
+  let reconnectedFolders = 0;
+  let reconnectedPhotos = 0;
+
+  const folderTargets: { name: string; handle: FileSystemDirectoryHandle }[] = [];
+  folderTargets.push({ name: newFolderHandle.name, handle: newFolderHandle });
+
+  const knownFolderNames = new Set([
+    ...existingFolders.map((f) => f.name),
+    ...allPhotos.map((p) => p.folder),
+  ]);
+
+  for (const name of knownFolderNames) {
+    if (folderTargets.some((t) => t.name === name)) continue;
+    try {
+      const sub = await openAt(newFolderHandle, name);
+      if (sub) {
+        folderTargets.push({ name, handle: sub });
+      }
+    } catch {}
+  }
+
+  const db = await openDb();
+  await new Promise<void>((resolve, reject) => {
+    const tx = db.transaction(FOLDERS, 'readwrite');
+    const store = tx.objectStore(FOLDERS);
+    for (const target of folderTargets) {
+      store.put({ name: target.name, handle: target.handle });
+      reconnectedFolders++;
+    }
+    tx.oncomplete = () => resolve();
+    tx.onerror = () => reject(tx.error);
+  });
+
+  const photosToUpdate: LibraryPhoto[] = [];
+  for (const target of folderTargets) {
+    const matchingPhotos = allPhotos.filter((p) => p.folder === target.name && !p.handle);
+    if (!matchingPhotos.length) continue;
+
+    const dirCache = new Map<string, FileSystemDirectoryHandle>();
+    dirCache.set('', target.handle);
+
+    for (const p of matchingPhotos) {
+      try {
+        let dirHandle = dirCache.get(p.dir);
+        if (!dirHandle) {
+          const opened = await openAt(target.handle, p.dir);
+          if (!opened) continue;
+          dirCache.set(p.dir, opened);
+          dirHandle = opened;
+        }
+        const fileHandle = await dirHandle.getFileHandle(p.name);
+        if (fileHandle) {
+          p.handle = fileHandle;
+          photosToUpdate.push(p);
+          reconnectedPhotos++;
+        }
+      } catch {}
+    }
+  }
+
+  if (photosToUpdate.length) {
+    await new Promise<void>((resolve, reject) => {
+      const tx = db.transaction(PHOTOS, 'readwrite');
+      const store = tx.objectStore(PHOTOS);
+      for (const p of photosToUpdate) {
+        store.put(p);
+      }
+      tx.oncomplete = () => resolve();
+      tx.onerror = () => reject(tx.error);
+    });
+  }
+
+  return { reconnectedFolders, reconnectedPhotos };
+}
+
 // The picker's own dialog; `id` makes the browser reopen at the folder this page
 // was last pointed at, which is what makes a second visit one click.
 export async function pickFolder(): Promise<LibraryFolder | null> {
@@ -292,6 +372,7 @@ export async function pickFolder(): Promise<LibraryFolder | null> {
   ).showDirectoryPicker({ mode: 'readwrite', id: 'recipescam-library' });
   const folder: LibraryFolder = { name: handle.name, handle };
   await ask(FOLDERS, 'readwrite', (s) => s.put(folder));
+  await reconnectPhotosForFolders(handle);
   return folder;
 }