android: a folder of audio files, and a paste of track links

The paste door now reads itself the way the desktop's does: one track link
in the paste and every line is looked up on its own public page
(playlist_import_track_links), which is the way past Spotify's 100-track
public ceiling — the wait screen counts them as they arrive. A fourth door
imports a folder of audio files off this phone, picked with the storage
plugin's own document-tree picker; playlist_import_folder grew a path
argument for it, because on Android it had no dialog to open and always
answered nothing. A YouTube playlist link needed no door at all — the link
one already dispatches it.

src/mobile/HalfSheet.svelte

@@ -13,7 +13,7 @@
     import { streamSong, saveSong, streamCatalogAlbum, saveCatalogAlbum } from "./resolve.svelte.js";
     import { catalog, yearOf } from "./catalog.svelte.js";
     import { pls, bulk, bulkable, runBulk, coverFor, queueable, entryOf, playFrom, shufflePlay, togglePin, renamePlaylist, describePlaylist, duplicatePlaylist, deletePlaylist, removeItems, addEntries, createPlaylist, moveItem, coverFromPhoto, coverClear } from "./playlists.svelte.js";
-    import { DOORS, start as startImport } from "./importer.svelte.js";
+    import { DOORS, start as startImport, pickImportFolder, startFolder } from "./importer.svelte.js";
     import { slsk, refreshRooms, disconnect, openThread, addBuddy, removeBuddy, leaveRoom } from "./slsk.svelte.js";
     import { lib, albumById, albumsBy, tracksOf, loadLibrary, refreshPlaylists, refreshRecents } from "./lib.svelte.js";
     import { lyr, nudge, searchCandidates, closeCandidates, chooseCandidate, forgetLyrics, pasteLyrics, setAutoSync, openTapSync, tapProgress, reduceVocals, backToOriginal } from "./lyrics.svelte.js";
@@ -146,6 +146,17 @@
             onsubmit: (v) => { push("import", {}); void startImport(door, v); },
         });
     }
+    /* the folder door picks FIRST: the review only opens for a folder that
+       was chosen, and a tree with no path on this phone cannot be walked */
+    async function folderDoor() {
+        closeHalf();
+        try {
+            const path = await pickImportFolder();
+            if (!path) return;
+            push("import", {});
+            void startFolder(path);
+        } catch (e) { oops(e); }
+    }
     /* find a local match — the desktop's repair panel, on a sheet: the
        library searched by the row's name, a pick relinks the row (an
        unknown placeholder adopts the track's identity; the original line
@@ -494,10 +505,10 @@
             <div class="sheet-title">Import a playlist</div>
             <div class="sheet-rows">
                 {#each DOORS as [door, icon, t, m] (door)}
-                    {@render row(icon, t, m, () => importPrompt(door))}
+                    {@render row(icon, t, m, () => (door === "folder" ? folderDoor() : importPrompt(door)))}
                 {/each}
             </div>
-            <div class="sec-note" style="padding-bottom: 14px">A playlist file or a folder of audio files imports on the desktop, where the files are.</div>
+            <div class="sec-note" style="padding-bottom: 14px">A playlist file — M3U, XSPF, PLS or CSV — imports on the desktop; the phone has no file picker for one yet.</div>
         {:else if kind === "plmatch" && shown?.arg?.item}
             {@const p = shown.arg.playlist}
             {@const item = shown.arg.item}

src/mobile/Mobile.svelte

@@ -47,7 +47,7 @@
     import { resolver, streamSong, streamCatalogAlbum } from "./resolve.svelte.js";
     import { notice, clearNote } from "./notice.svelte.js";
     import * as pls from "./playlists.svelte.js";
-    import { importer, bindImporter } from "./importer.svelte.js";
+    import { importer, bindImporter, startFolder } from "./importer.svelte.js";
     import { bindShare } from "./share.svelte.js";
     import { downloadsAllowed, cellular } from "./network.svelte.js";
     import { contacts, loadContacts, display } from "./contacts.svelte.js";
@@ -197,7 +197,7 @@
         setTimeout(() => { api.libraryArtPrewarm([360]).catch(() => {}); }, 8000);
         /* the probe handle — the desktop has __soulstream for the same reason:
            tests/mobile/smoke.mjs drives the real app through it */
-        window.__ss = { nav, top, go, push, back, openSheet, closeSheet, openHalf, closeHalf, player, lib, art, slsk, net, resolver, streamSong, streamCatalogAlbum, sources, api, transfers, pls, notice, importer, wifi: { downloadsAllowed, cellular }, next, prev, toggle, seekSecs, playQueueAt, patch, contacts, loadContacts };
+        window.__ss = { nav, top, go, push, back, openSheet, closeSheet, openHalf, closeHalf, player, lib, art, slsk, net, resolver, streamSong, streamCatalogAlbum, sources, api, transfers, pls, notice, importer, imp: { startFolder }, wifi: { downloadsAllowed, cellular }, next, prev, toggle, seekSecs, playQueueAt, patch, contacts, loadContacts };
         return () => { if (unlisten) unlisten(); };
     });
 </script>

src/mobile/importer.svelte.js

@@ -1,8 +1,9 @@
 /* Importing a playlist on the phone — the desktop's PlaylistImportModal's
-   rules, on the doors that need no tool and no file: a link (YouTube ·
-   Spotify · Apple Music · TIDAL · Deezer), a pasted tracklist (plain lines,
-   a timestamped setlist, or pasted track links), a YouTube DJ set's posted
-   tracklist. The backend stages a draft (parsing and resolution against
+   rules, on the doors that need no file picker: a link (YouTube · Spotify ·
+   Apple Music · TIDAL · Deezer), a pasted tracklist (plain lines, a
+   timestamped setlist, or track links — a paste holding one is read as
+   links), a YouTube DJ set's posted tracklist, and a folder of audio files
+   on this phone. The backend stages a draft (parsing and resolution against
    the library); nothing is written until commit. While the review is up
    the stream rows are verified against the catalog — the desktop's
    verifyStreams, verbatim: the ISRC first, then the hardened name walk —
@@ -13,7 +14,7 @@ import { findCatalogTrack } from "../lib/catalogMatch.js";
 import { refreshPlaylists } from "./lib.svelte.js";
 
 export const importer = $state({
-    door: null,        // "link" | "text" | "youtube"
+    door: null,        // "link" | "text" | "youtube" | "folder"
     source: "",        // what was pasted
     busy: false,
     error: "",
@@ -23,29 +24,44 @@ export const importer = $state({
     includeUnresolved: true,
     checks: {},        // ordinal → "checking" | { album, cover, anchored } | "none"
     committing: false,
+    links: false,      // the paste held track links: each read off its own page
 });
 
 export const FORMAT_LABEL = {
     m3u: "M3U", pls: "PLS", xspf: "XSPF", csv: "CSV", soulstream: "SoulStream backup",
     text: "Pasted text", folder: "Folder", youtube: "YouTube", "youtube-playlist": "YouTube playlist",
     spotify: "Spotify", "apple-music": "Apple Music", tidal: "TIDAL", deezer: "Deezer",
+    links: "Pasted links",
 };
-/** [door, icon, title, hint] — the desktop's Import menu, minus the file
- *  and folder doors (the files are on the desktop). */
+
+/* Mirrors the backend's detector closely enough to CHOOSE a door; the
+   backend decides for real. A paste holding even one track link takes the
+   link path, so a list copied out of Spotify never parses as track names. */
+const TRACK_LINK = /(?:spotify:track:[A-Za-z0-9]{22})|(?:\/\/(?:open\.spotify\.com\/(?:[\w-]+\/)*track\/|(?:www\.)?deezer\.com\/(?:[\w-]+\/)*track\/|(?:[\w-]+\.)?tidal\.com\/(?:[\w-]+\/)*track\/|music\.apple\.com\/[^\s]*(?:\/song\/|[?&]i=)))/i;
+
+/** [door, icon, title, hint] — the desktop's Import menu, minus the
+ *  playlist-file door (that one still wants a file picker). A YouTube
+ *  playlist link goes through "link": the backend dispatches it. */
 export const DOORS = [
     ["link", "link", "Playlist from a link…", "YouTube · Spotify · Apple Music · TIDAL · Deezer"],
     ["text", "pencil", "Paste a tracklist…", "plain lines, a timestamped setlist, or track links"],
     ["youtube", "brand-youtube", "YouTube DJ set…", "tracks from chapters, description or comments"],
+    ["folder", "folder-open", "Folder of audio files…", "tag or natural order"],
 ];
 
 let gen = 0;
 /** Open a door: the backend reads and resolves, the review shows the draft. */
 export async function start(door, source) {
     const g = ++gen;
-    Object.assign(importer, { door, source, busy: true, error: "", progress: null, draft: null, name: "", includeUnresolved: true, checks: {}, committing: false });
+    /* the paste reads itself: one track link in it and every line is
+       looked up on its own public page — the desktop's rule, and the way
+       past Spotify's 100-track public ceiling */
+    const links = door === "text" && TRACK_LINK.test(source || "");
+    Object.assign(importer, { door, source, busy: true, error: "", progress: null, draft: null, name: "", includeUnresolved: true, checks: {}, committing: false, links });
     try {
         const draft = door === "link" ? await api.playlistImportLink(source)
             : door === "youtube" ? await api.playlistImportYoutube(source)
+            : links ? await api.playlistImportTrackLinks(source, null)
             : await api.playlistImportText(source);
         if (g !== gen) return;
         importer.draft = draft;
@@ -56,6 +72,36 @@ export async function start(door, source) {
         if (g === gen) { importer.error = String(e); importer.busy = false; }
     }
 }
+/** 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; }
+    }
+}
 /** The rows commit will send: streams are first-class; the switch only
  *  gates the TRUE unknowns. */
 export function kept() {

src/mobile/screens/Import.svelte

@@ -42,7 +42,11 @@
         if (r) replace("playlist", { id: r.id });
     }
     function leave() { cancel(); back(); }
-    const waitLine = $derived(importer.door === "link" ? "Reading the link…" : importer.door === "youtube" ? "Reading the set's tracklist…" : "Reading the tracklist…");
+    const waitLine = $derived(importer.door === "link" ? "Reading the link…"
+        : importer.door === "youtube" ? "Reading the set's tracklist…"
+        : importer.door === "folder" ? "Reading the folder…"
+        : importer.links ? "Reading the pasted links…"
+        : "Reading the tracklist…");
 </script>
 
 {#if importer.busy}