/** The folder door picks FIRST — the phone's own document-tree picker — so
 *  the review only opens for a folder that was actually chosen. The tree has
 *  to be on this phone's storage: the backend walks a path, and a cloud
 *  provider's tree has none. Returns null when the picker was dismissed. */
export async function pickImportFolder() {
    let picked;
    try { picked = await api.pickLibraryFolder(); }
    catch (e) { if (/cancelled/.test(String(e))) return null; throw e; }
    if (!picked?.path) throw new Error("That folder has no path the phone can read — pick one on this phone's storage.");
    return picked.path;
}
/** Stage a folder of audio files. The backend walks the folder and its disc
 *  subfolders, orders by the files' own track numbers when every one carries
 *  a distinct one and by natural filename order otherwise, and matches each
 *  file against the library by path. Every row comes back local, so there is
 *  nothing for the catalog pass to verify. */
export async function startFolder(path) {
    const g = ++gen;
    Object.assign(importer, { door: "folder", source: path, busy: true, error: "", progress: null, draft: null, name: "", includeUnresolved: true, checks: {}, committing: false, links: false });
    try {
        const draft = await api.playlistImportFolder(path);
        if (g !== gen) return;
        importer.busy = false;
        if (!draft) { importer.error = "Nothing came back from that folder."; return; }
        importer.draft = draft;
        importer.name = draft.name ?? "";
    } catch (e) {
        if (g === gen) { importer.error = String(e); importer.busy = false; }
    }
}