fix(queue): Lucky Mix uses one undo snapshot for Ctrl+Z (#728)

Many prune/play/enqueue steps exhausted QUEUE_UNDO_MAX and dropped the
pre-mix snapshot. Push undo once before the macro rebuild; add skipQueueUndo
for enqueue and pruneUpcomingToCurrent; Lucky Mix playTrack uses manual=false.

CHANGELOG: document fix under 1.46.0 Fixed (PR #728).

CHANGELOG.md

@@ -540,6 +540,12 @@ Foundational work: faster reviews, narrower diffs, and a safety net under the pa
 
 * The three header dropdowns (Orbit launch, Server picker, Live listeners) each had their own container styling. Live in particular used a glass / backdrop-filter utility that read poorly on many themes. All three now share the **`.nav-library-dropdown-panel`** container — same background, border, shadow and radius via the existing semantic tokens. Item layouts per dropdown stay case-specific.
 
+### Queue — Lucky Mix coalesced into one Ctrl+Z / Cmd+Z undo step
+
+**By [@cucadmuh](https://github.com/cucadmuh), PR [#728](https://github.com/Psychotoxical/psysonic/pull/728)**
+
+* **Lucky Mix** ran many queue edits (`pruneUpcomingToCurrent`, **`playTrack`**, **`enqueue`** batches). Each pushed onto the bounded **`QUEUE_UNDO_MAX`** stack, so the snapshot taken **before** Lucky Mix was usually shifted off — Ctrl+Z only stepped through small edits or could not restore the prior queue. The mix flow now pushes **one** undo snapshot up-front and skips intermediate **`enqueue`** / prune snapshots (**`skipQueueUndo`**) so a single undo restores the queue from immediately **before** Lucky Mix.
+
 ## [1.45.0] - 2026-05-04
 
 ## Added

src/store/playerStoreTypes.ts

@@ -107,7 +107,8 @@ export interface PlayerState {
    updateReplayGainForCurrentTrack: () => void;
    reanalyzeLoudnessForTrack: (trackId: string) => Promise<void>;
    setProgress: (t: number, duration: number) => void;
-  enqueue: (tracks: Track[], _orbitConfirmed?: boolean) => void;
+  /** `_orbitConfirmed` bypasses the bulk-append gate. `skipQueueUndo` skips the undo snapshot (macro builders such as Lucky Mix push once up-front). */
+  enqueue: (tracks: Track[], _orbitConfirmed?: boolean, skipQueueUndo?: boolean) => void;
   enqueueAt: (tracks: Track[], insertIndex: number, _orbitConfirmed?: boolean) => void;
   /** "Play Next" — inserts after the current track. When
    *  `preservePlayNextOrder` is on, appends to the existing Play-Next streak
@@ -117,8 +118,9 @@ export interface PlayerState {
   playNext: (tracks: Track[]) => void;
   enqueueRadio: (tracks: Track[], artistId?: string) => void;
   setRadioArtistId: (artistId: string) => void;
-  /** For Lucky Mix: drop upcoming tail; keep the currently playing item only. */
+  /** For Lucky Mix: drop upcoming tail; keep the currently playing item only.
-  pruneUpcomingToCurrent: () => void;
+   * When `skipQueueUndo` is true, callers must push undo separately (macro rebuild). */
+  pruneUpcomingToCurrent: (skipQueueUndo?: boolean) => void;
   clearQueue: () => void;
 
   isQueueVisible: boolean;

src/store/queueMutationActions.ts

@@ -36,6 +36,8 @@ function blockCrossServerEnqueue(): boolean {
  * Eleven queue-mutation actions. Shared invariant: every action except
  * `setRadioArtistId` pushes a queue-undo snapshot and calls
  * `syncQueueToServer` so the Navidrome `savePlayQueue` stays in sync.
+ * Exceptions: `enqueue`'s optional third argument **`skipQueueUndo`** and
+ * **`pruneUpcomingToCurrent(true)`** — Lucky Mix pushes one snapshot up-front.
  */
 export function createQueueMutationActions(set: SetState, get: GetState): Pick<
   PlayerState,
@@ -52,15 +54,15 @@ export function createQueueMutationActions(set: SetState, get: GetState): Pick<
   | 'removeTrack'
 > {
   return {
-    enqueue: (tracks, _orbitConfirmed = false) => {
+    enqueue: (tracks, _orbitConfirmed = false, skipQueueUndo = false) => {
       if (blockCrossServerEnqueue()) return;
       if (!_orbitConfirmed && tracks.length > 1) {
         void orbitBulkGuard(tracks.length).then(ok => {
-          if (ok) get().enqueue(tracks, true);
+          if (ok) get().enqueue(tracks, true, skipQueueUndo);
         });
         return;
       }
-      pushQueueUndoFromGetter(get);
+      if (!skipQueueUndo) pushQueueUndoFromGetter(get);
       set(state => {
         // Insert before the first upcoming auto-added track so the
         // "Added automatically" separator always stays at the boundary.
@@ -181,17 +183,17 @@ export function createQueueMutationActions(set: SetState, get: GetState): Pick<
       get().enqueueAt(tagged, insertIdx);
     },
 
-    pruneUpcomingToCurrent: () => {
+    pruneUpcomingToCurrent: (skipQueueUndo = false) => {
       const s = get();
       if (s.currentRadio) return;
       if (!s.currentTrack) {
         if (s.queue.length === 0) return;
-        pushQueueUndoFromGetter(get);
+        if (!skipQueueUndo) pushQueueUndoFromGetter(get);
         set({ queue: [], queueIndex: 0 });
         syncQueueToServer([], null, 0);
         return;
       }
-      pushQueueUndoFromGetter(get);
+      if (!skipQueueUndo) pushQueueUndoFromGetter(get);
       const at = s.queue.findIndex(t => t.id === s.currentTrack!.id);
       const newQueue: Track[] =
         at >= 0

src/utils/mix/luckyMix.ts

@@ -6,6 +6,7 @@ import { songToTrack } from '../playback/songToTrack';
 import { invoke } from '@tauri-apps/api/core';
 import i18n from '../../i18n';
 import { useAuthStore } from '../../store/authStore';
+import { pushQueueUndoFromGetter } from '../../store/queueUndo';
 import { usePlayerStore } from '../../store/playerStore';
 import { useLuckyMixStore } from '../../store/luckyMixStore';
 import { isLuckyMixAvailable } from '../../hooks/useLuckyMixAvailable';
@@ -89,18 +90,20 @@ export async function buildAndPlayLuckyMix(): Promise<void> {
     queueIndex: playerStateBefore.queueIndex,
   };
 
-  // Drop the old "upcoming" tail immediately so the queue UI does not show stale
+  // One undo step for the whole Lucky Mix run — internal prune/play/enqueue
-  // next tracks while the mix is still building (first playTrack may be delayed).
+  // batches must not each push (QUEUE_UNDO_MAX would drop this snapshot).
-  usePlayerStore.getState().pruneUpcomingToCurrent();
+  pushQueueUndoFromGetter(() => usePlayerStore.getState());
 
-  lucky.start();
-  // Per-run handles. Live outside the try so `finally`/`catch` can read
-  // `startedPlayback` (drives the queue-restore decision) and clean up the
-  // player-store subscription unconditionally.
   let unsubPlayer: (() => void) | null = null;
-  let startedPlayback = false;
   try {
-    let allSeedSongs: SubsonicSong[] = [];
+    // Drop the old "upcoming" tail immediately so the queue UI does not show stale
+    // next tracks while the mix is still building (first playTrack may be delayed).
+    usePlayerStore.getState().pruneUpcomingToCurrent(true);
+
+    lucky.start();
+    let startedPlayback = false;
+    try {
+      let allSeedSongs: SubsonicSong[] = [];
 
     const mixQueueSize = () => usePlayerStore.getState().queue.length;
     const mixQueueTrackIds = () => new Set(usePlayerStore.getState().queue.map(t => t.id));
@@ -117,7 +120,7 @@ export async function buildAndPlayLuckyMix(): Promise<void> {
       const play = allowed[0];
       startedPlayback = true;
       const track = songToTrack(play);
-      usePlayerStore.getState().playTrack(track, [track], true);
+      usePlayerStore.getState().playTrack(track, [track], false);
       logStep('start_immediate_playback', {
         source,
         song: songDebug([play])[0],
@@ -160,7 +163,7 @@ export async function buildAndPlayLuckyMix(): Promise<void> {
       const toAdd = sampleRandom(candidates, Math.min(remaining, candidates.length));
       if (!toAdd.length) return 0;
       const before = mixQueueSize();
-      usePlayerStore.getState().enqueue(toAdd.map(songToTrack), true);
+      usePlayerStore.getState().enqueue(toAdd.map(songToTrack), true, true);
       const added = mixQueueSize() - before;
       logStep('append_queue_batch', {
         reason,
@@ -373,6 +376,7 @@ export async function buildAndPlayLuckyMix(): Promise<void> {
       });
     }
     showToast(i18n.t('luckyMix.failed'), 5000, 'error');
+  }
   } finally {
     if (unsubPlayer) { try { unsubPlayer(); } catch { /* noop */ } }
     useLuckyMixStore.getState().stop();