From b11882c99372a95b61d8994fefdc6de506631b0a Mon Sep 17 00:00:00 2001
From: Janis Hutz <development@janishutz.com>
Date: Tue, 8 Sep 2026 11:20:17 +0200
Subject: [PATCH] feat: improve sync

---
 backend/src/manager/rooms/index.ts            |  9 ++--
 backend/src/manager/rooms/room.d.ts           |  1 +
 backend/src/routes/room/update.ts             |  3 +-
 web/src/components/player/PlayerControls.vue  |  3 ++
 web/src/components/player/ProgressBar.vue     |  7 ++-
 .../components/playlists/UserPlaylists.vue    | 11 +---
 web/src/components/shared/SharedQueue.vue     | 52 ++++++++++---------
 web/src/scss/components/progressbar.scss      |  4 ++
 web/src/ts/dtype/global.d.ts                  |  5 ++
 web/src/ts/messages/index.ts                  | 28 ++++++++--
 web/src/ts/player/index.ts                    |  6 +--
 web/src/ts/player/playlists/add.ts            |  6 +--
 web/src/ts/player/playlists/index.ts          |  5 +-
 web/src/ts/shared/index.ts                    |  4 ++
 web/src/ts/shared/messageHandler.ts           |  5 ++
 web/src/ts/shared/state.ts                    |  6 +++
 web/src/ts/userPlaylists/index.ts             | 13 +++++
 web/src/ts/userPlaylists/save.ts              |  6 ++-
 web/src/views/SharedView.vue                  | 41 ++++++++++++++-
 19 files changed, 160 insertions(+), 55 deletions(-)

diff --git a/backend/src/manager/rooms/index.ts b/backend/src/manager/rooms/index.ts
index 30f223b..aed0ea6 100644
--- a/backend/src/manager/rooms/index.ts
+++ b/backend/src/manager/rooms/index.ts
@@ -41,7 +41,8 @@ const create = ( name: string, uid: string ) => {
                 'index': 0,
                 'lastUpdate': new Date().getTime(),
                 'playing': false,
-                'start': new Date().getTime()
+                'start': new Date().getTime(),
+                'offset': 0
             }
         };
 
@@ -112,9 +113,10 @@ const close = ( name: string, uid: string ) => {
  * @param playing - Set to true if the player is playing currently
  * @param index - The current playback index
  * @param start - The timestamp where playback of the current song started
+ * @param offset - The playback offset from the start in seconds
  * @returns true if update succeeded
  */
-const updateState = ( room: string, uid: string, playing: boolean, index: number, start: number ) => {
+const updateState = ( room: string, uid: string, playing: boolean, index: number, start: number, offset: number ) => {
     if ( !rooms[room] || rooms[room].owner !== uid ) {
         return false;
     }
@@ -123,7 +125,8 @@ const updateState = ( room: string, uid: string, playing: boolean, index: number
         'playing': playing,
         'index': index,
         'lastUpdate': new Date().getTime(),
-        'start': start
+        'start': start,
+        'offset': offset
     };
 
     return sendUpdate( room, 'state' );
diff --git a/backend/src/manager/rooms/room.d.ts b/backend/src/manager/rooms/room.d.ts
index 3d85963..6c95162 100644
--- a/backend/src/manager/rooms/room.d.ts
+++ b/backend/src/manager/rooms/room.d.ts
@@ -20,6 +20,7 @@ export interface Room {
         'start': number;
         'playing': boolean;
         'lastUpdate': number;
+        'offset': number;
     };
     'owner': string;
     'clients': Client[];
diff --git a/backend/src/routes/room/update.ts b/backend/src/routes/room/update.ts
index ddf36d2..18b4c63 100644
--- a/backend/src/routes/room/update.ts
+++ b/backend/src/routes/room/update.ts
@@ -79,7 +79,8 @@ const routes = ( app: express.Application, foss: boolean, config: Config ) => {
                     sdk.getUID( request )!,
                     request.body.playing ?? false,
                     request.body.index ?? -1,
-                    request.body.start ?? new Date().getTime()
+                    request.body.start ?? new Date().getTime(),
+                    request.body.offset ?? 0
                 ) )
                     response.sendStatus( 200 );
                 else
diff --git a/web/src/components/player/PlayerControls.vue b/web/src/components/player/PlayerControls.vue
index d4f8277..6570030 100644
--- a/web/src/components/player/PlayerControls.vue
+++ b/web/src/components/player/PlayerControls.vue
@@ -8,6 +8,7 @@
     import {
         beautifyTime
     } from '@/ts/util/time';
+    import messages from '@/ts/messages';
     import player from '@/ts/player';
 
     const playbackPercentage = player.playbackPercentage;
@@ -42,6 +43,8 @@
     const duration = computed( () => {
         return beautifyTime( player.duration.value );
     } );
+
+    messages.useRoomWatchers();
 </script>
 
 <template>
diff --git a/web/src/components/player/ProgressBar.vue b/web/src/components/player/ProgressBar.vue
index 7b658ac..72f5bb3 100644
--- a/web/src/components/player/ProgressBar.vue
+++ b/web/src/components/player/ProgressBar.vue
@@ -12,8 +12,13 @@
     const offset = ref( -1 );
     const isMoving = ref( false );
     const bar = useTemplateRef( 'bar' );
+    const props = defineProps<{
+        'disallowMove'?: boolean
+    }>();
 
     const start = ( ev: MouseEvent ) => {
+        if ( props.disallowMove ) return;
+
         offset.value = bar.value!.getBoundingClientRect().x;
         isMoving.value = true;
         moveVal.value = ( ev.x - offset.value ) / bar.value!.clientWidth;
@@ -47,7 +52,7 @@
             <div :style="`width: ${ isMoving ? moveVal * 100 : val * 100 }%;`"></div>
         </div>
         <div
-            :class="['click-target', offset >= 0 ? 'active' : undefined]"
+            :class="['click-target', offset >= 0 ? 'active' : undefined, props.disallowMove ? 'disallowed' : undefined]"
             @mousedown="start"
             @mousemove="move"
             @mouseup="end"
diff --git a/web/src/components/playlists/UserPlaylists.vue b/web/src/components/playlists/UserPlaylists.vue
index 4eaf5db..42eb691 100644
--- a/web/src/components/playlists/UserPlaylists.vue
+++ b/web/src/components/playlists/UserPlaylists.vue
@@ -1,11 +1,11 @@
 <script setup lang="ts">
     import {
         addPlaylist,
-        removePlaylist
+        removePlaylist,
+        selectPlaylist
     } from '@/ts/userPlaylists';
     import {
         editingPlaylists,
-        playlistIdx as playlistIdx,
         playlists
     } from '@/ts/userPlaylists/state';
     import {
@@ -20,7 +20,6 @@
     import {
         UnownedError
     } from '@/ts/request';
-    import player from '@/ts/player';
     import router from '@/router';
 
     const checkingStatus = ref( true );
@@ -65,12 +64,6 @@
     const togglePlaylistEditing = ( idx: number ) => {
         editingPlaylists.value[ idx ] = !editingPlaylists.value[ idx ];
     };
-
-    const selectPlaylist = ( idx: number ) => {
-        playlistIdx.value = idx;
-        player.clearQueue();
-        player.loadPlaylist( playlists.value[ idx ]!.songs );
-    };
 </script>
 
 <template>
diff --git a/web/src/components/shared/SharedQueue.vue b/web/src/components/shared/SharedQueue.vue
index 0444426..6bd5219 100644
--- a/web/src/components/shared/SharedQueue.vue
+++ b/web/src/components/shared/SharedQueue.vue
@@ -1,16 +1,15 @@
 <script setup lang="ts">
-    import {
-        computed,
-        ref
-    } from 'vue';
     import {
         currentQueue,
-        currentQueueIdx
+        currentQueueIdx,
+        playbackTime,
+        showArtworks
     } from '@/ts/shared/state';
+    import {
+        computed
+    } from 'vue';
 
     const songs = computed( () => currentQueue.value?.slice( currentQueueIdx.value + 1 ) ?? [] );
-    // TODO: Move this out of this file
-    const showArtworks = ref( false );
     const timeToPlay = computed( () => {
         return ( idx: number ) => {
             let total = 0;
@@ -20,6 +19,7 @@
             }
 
             total += currentQueue.value[ currentQueueIdx.value ]?.duration ?? 0;
+            total -= playbackTime.value;
 
             return Math.round( total / 60 );
         };
@@ -27,24 +27,26 @@
 </script>
 
 <template>
-    <div class="queue-container">
-        <div v-for="(song, index) in songs" :key="index" class="song-list-element">
-            <div class="song-cover-wrapper">
-                <img
-                    v-if="song.artwork && showArtworks"
-                    :src="song.artwork"
-                    alt="Song cover"
-                    class="song-cover"
-                >
-                <i v-else class="fa-solid fa-music song-cover"></i>
-            </div>
-            <div class="song-details">
-                <h3>{{ song.name }}</h3>
-                <p>{{ song.artist }}</p>
-                <p>{{ song['additional-info'] }}</p>
-            </div>
-            <div class="song-actions">
-                <p>In {{ timeToPlay( index ) }}min</p>
+    <div class="queue-viewer">
+        <div class="queue-container">
+            <div v-for="(song, index) in songs" :key="index" class="song-list-element">
+                <div class="song-cover-wrapper">
+                    <img
+                        v-if="song.artwork && showArtworks"
+                        :src="song.artwork"
+                        alt="Song cover"
+                        class="song-cover"
+                    >
+                    <i v-else class="fa-solid fa-music song-cover"></i>
+                </div>
+                <div class="song-details">
+                    <h3>{{ song.name }}</h3>
+                    <p>{{ song.artist }}</p>
+                    <p>{{ song['additional-info'] }}</p>
+                </div>
+                <div class="song-actions">
+                    <p>In {{ timeToPlay( index ) }}min</p>
+                </div>
             </div>
         </div>
     </div>
diff --git a/web/src/scss/components/progressbar.scss b/web/src/scss/components/progressbar.scss
index 0778834..93504e3 100644
--- a/web/src/scss/components/progressbar.scss
+++ b/web/src/scss/components/progressbar.scss
@@ -33,5 +33,9 @@
       position: fixed;
       z-index: 10000;
     }
+
+    &.disallowed {
+      cursor: default;
+    }
   }
 }
diff --git a/web/src/ts/dtype/global.d.ts b/web/src/ts/dtype/global.d.ts
index a630514..9cab2e4 100644
--- a/web/src/ts/dtype/global.d.ts
+++ b/web/src/ts/dtype/global.d.ts
@@ -4,4 +4,9 @@ import type {
 
 declare global {
     var MusicKit: MusicKitObject;
+    interface GlobalEventHandlersEventMap {
+        'musicplayer:playpause': CustomEvent<void>;
+        'musicplayer:playindex': CustomEvent<void>;
+        'musicplayer:seek': CustomEvent<void>;
+    }
 }
diff --git a/web/src/ts/messages/index.ts b/web/src/ts/messages/index.ts
index 0f476a7..3349758 100644
--- a/web/src/ts/messages/index.ts
+++ b/web/src/ts/messages/index.ts
@@ -4,6 +4,8 @@ import {
     queueIdx
 } from '../player/state';
 import {
+    onMounted,
+    onUnmounted,
     ref,
     watch
 } from 'vue';
@@ -116,7 +118,8 @@ const sendStateData = () => {
         request.post( `/room/${ room.value }/update/state`, JSON.stringify( {
             'playing': isPlaying.value,
             'index': queueIdx.value,
-            'start': new Date().getTime() - ( playbackPercentage.value * ( queue.value[ queueIdx.value ]?.duration ?? 0 ) ) - 100
+            'start': new Date().getTime() - 100,
+            'offset': playbackPercentage.value * ( queue.value[ queueIdx.value ]?.duration ?? 0 )
         } ) );
 
         setTimeout( () => {
@@ -128,10 +131,25 @@ const sendStateData = () => {
 const useRoomWatchers = () => {
     watch( queue, sendPlaylistData );
 
-    watch( [
-        isPlaying,
-        queueIdx
-    ], sendStateData );
+    onMounted( () => {
+        document.addEventListener( 'musicplayer:playindex', sendStateData );
+        document.addEventListener( 'musicplayer:seek', sendStateData );
+        document.addEventListener( 'musicplayer:playpause', sendStateData );
+    } );
+
+    onUnmounted( () => {
+        try {
+            document.addEventListener( 'musicplayer:play', sendStateData );
+        } catch { /* empty */ }
+
+        try {
+            document.addEventListener( 'musicplayer:seek', sendStateData );
+        } catch { /* empty */ }
+
+        try {
+            document.addEventListener( 'musicplayer:playpause', sendStateData );
+        } catch { /* empty */ }
+    } );
 
     if ( room.value ) connect();
 };
diff --git a/web/src/ts/player/index.ts b/web/src/ts/player/index.ts
index 1360a7b..4130d97 100644
--- a/web/src/ts/player/index.ts
+++ b/web/src/ts/player/index.ts
@@ -29,7 +29,6 @@ import type {
 import {
     load
 } from './playlists/loader';
-import messages from '../messages';
 import {
     playIndex
 } from './playlists';
@@ -52,6 +51,7 @@ const play = () => {
 
     sources[currentSource.value]?.play();
     startTracking();
+    document.dispatchEvent( new CustomEvent( 'musicplayer:playpause' ) );
 };
 
 const pause = () => {
@@ -61,6 +61,7 @@ const pause = () => {
 
     sources[currentSource.value]?.pause();
     stopTracking();
+    document.dispatchEvent( new CustomEvent( 'musicplayer:playpause' ) );
 };
 
 /**
@@ -71,6 +72,7 @@ const seekTo = ( pos: number ) => {
     if ( currentSource.value === '' ) return;
 
     sources[currentSource.value]?.seekTo( pos );
+    document.dispatchEvent( new CustomEvent( 'musicplayer:seek' ) );
 };
 
 const skip10 = () => {
@@ -153,8 +155,6 @@ const addSongFromSource = async ( source: string, cb?: ( songs: Song[] ) => void
     return true;
 };
 
-messages.useRoomWatchers();
-
 export default {
     play,
     pause,
diff --git a/web/src/ts/player/playlists/add.ts b/web/src/ts/player/playlists/add.ts
index 8ce8fa7..9ffcc66 100644
--- a/web/src/ts/player/playlists/add.ts
+++ b/web/src/ts/player/playlists/add.ts
@@ -16,8 +16,8 @@ import type {
     Song
 } from '@/ts/dtype/playlist';
 import {
-    playlistIdx
-} from '@/ts/userPlaylists/state';
+    setPlaylistIdx
+} from '@/ts/userPlaylists';
 
 export const addSongList = ( songs: Song[] ) => {
     rawQueue.value = rawQueue.value.concat( songs );
@@ -25,7 +25,7 @@ export const addSongList = ( songs: Song[] ) => {
 };
 
 export const clearQueue = () => {
-    playlistIdx.value = -1;
+    setPlaylistIdx( 0 );
     queue.value = [];
     rawQueue.value = [];
     sources[currentSource.value]?.stop();
diff --git a/web/src/ts/player/playlists/index.ts b/web/src/ts/player/playlists/index.ts
index ee22a5e..46a8dcd 100644
--- a/web/src/ts/player/playlists/index.ts
+++ b/web/src/ts/player/playlists/index.ts
@@ -15,7 +15,7 @@ import {
  * Play a song at the given index of the queue. Wraps to 0 and end if index below 0 or above end
  * @param idx - The index in the queue to play at
  */
-export const playIndex = async ( idx: number ) => {
+export const playIndex = ( idx: number ) => {
     if ( idx >= queue.value.length ) {
         idx = repeat.value === 'all' ? 0 : -1;
     } else if ( idx < 0 ) {
@@ -42,4 +42,7 @@ export const playIndex = async ( idx: number ) => {
     startTracking();
 
     isPlaying.value = true;
+    setTimeout( () => {
+        document.dispatchEvent( new CustomEvent( 'musicplayer:playindex', {} ) );
+    }, 500 );
 };
diff --git a/web/src/ts/shared/index.ts b/web/src/ts/shared/index.ts
index 71e0c19..ec29d08 100644
--- a/web/src/ts/shared/index.ts
+++ b/web/src/ts/shared/index.ts
@@ -6,6 +6,8 @@ import {
     currentQueue,
     currentQueueIdx,
     isPlaying,
+    playbackOffset,
+    playbackTime,
     startTime
 } from './state';
 import type {
@@ -40,6 +42,8 @@ const connect = (): Promise<void> => {
             currentQueueIdx.value = data.state.index;
             isPlaying.value = data.state.playing;
             startTime.value = data.state.start;
+            playbackTime.value = data.state.offset;
+            playbackOffset.value = data.state.offset;
 
             resolve();
         };
diff --git a/web/src/ts/shared/messageHandler.ts b/web/src/ts/shared/messageHandler.ts
index 8e76b78..485a4cd 100644
--- a/web/src/ts/shared/messageHandler.ts
+++ b/web/src/ts/shared/messageHandler.ts
@@ -2,6 +2,8 @@ import {
     currentQueue,
     currentQueueIdx,
     isPlaying,
+    playbackOffset,
+    playbackTime,
     startTime
 } from './state';
 import type {
@@ -17,6 +19,7 @@ export interface StateUpdate {
     'playing': boolean;
     'index': number;
     'start': number;
+    'offset': number;
 }
 
 export const messageHandler = ( msg: string ) => {
@@ -36,6 +39,8 @@ export const messageHandler = ( msg: string ) => {
                 currentQueueIdx.value = state.index;
                 isPlaying.value = state.playing;
                 startTime.value = state.start;
+                playbackTime.value = state.offset;
+                playbackOffset.value = state.offset;
             } else {
                 console.log( '[SSE] Received unknown data', data.type );
             }
diff --git a/web/src/ts/shared/state.ts b/web/src/ts/shared/state.ts
index f2fc710..3cf4f6a 100644
--- a/web/src/ts/shared/state.ts
+++ b/web/src/ts/shared/state.ts
@@ -13,3 +13,9 @@ export const isPlaying = ref( false );
 export const currentQueueIdx = ref( -1 );
 
 export const startTime = ref( new Date().getTime() );
+
+export const showArtworks = ref( false );
+
+export const playbackTime = ref( 0 );
+
+export const playbackOffset = ref( 0 );
diff --git a/web/src/ts/userPlaylists/index.ts b/web/src/ts/userPlaylists/index.ts
index b8a6f84..ca86ad0 100644
--- a/web/src/ts/userPlaylists/index.ts
+++ b/web/src/ts/userPlaylists/index.ts
@@ -1,7 +1,10 @@
 import {
     editingPlaylists,
+    playlistIdx,
     playlists
 } from './state';
+import player from '../player';
+
 
 export const addPlaylist = ( name: string ) => {
     playlists.value.push( {
@@ -17,3 +20,13 @@ export const removePlaylist = ( idx: number ) => {
         editingPlaylists.value.splice( idx, 1 );
     }
 };
+
+export const selectPlaylist = ( idx: number ) => {
+    playlistIdx.value = idx;
+    player.clearQueue();
+    player.loadPlaylist( playlists.value[ idx ]!.songs );
+};
+
+export const setPlaylistIdx = ( idx: number ) => {
+    playlistIdx.value = idx;
+};
diff --git a/web/src/ts/userPlaylists/save.ts b/web/src/ts/userPlaylists/save.ts
index 2349a20..f3d00b7 100644
--- a/web/src/ts/userPlaylists/save.ts
+++ b/web/src/ts/userPlaylists/save.ts
@@ -16,15 +16,17 @@ import {
     useNotification
 } from '@kyvg/vue3-notification';
 
-export const savePlaylist = async () => {
+export const savePlaylist = () => {
     rawQueue.value = queue.value;
     shuffle.value = false;
 
-    if ( playlistIdx.value ) {
+    if ( playlistIdx.value < 0 ) {
         let name: null | string = '';
 
         while ( !name || name.length === 0 ) {
             name = prompt( 'You are trying to save a playlist that has not previously been created. Please enter a name for it' );
+
+            if ( !name ) return;
         }
 
         addPlaylist( name );
diff --git a/web/src/views/SharedView.vue b/web/src/views/SharedView.vue
index 497372d..a9fbe83 100644
--- a/web/src/views/SharedView.vue
+++ b/web/src/views/SharedView.vue
@@ -1,21 +1,49 @@
 <script setup lang="ts">
     import {
         type ComputedRef,
-        computed
+        computed,
+        onMounted,
+        ref
     } from 'vue';
     import {
         currentQueue,
-        currentQueueIdx
+        currentQueueIdx,
+        isPlaying,
+        playbackOffset,
+        playbackTime,
+        startTime
     } from '@/ts/shared/state';
     import CurrentSong from '@/components/player/CurrentSong.vue';
+    import ProgressBar from '@/components/player/ProgressBar.vue';
     import SharedQueue from '@/components/shared/SharedQueue.vue';
     import type {
         Song
     } from '@/ts/dtype/playlist';
+    import {
+        beautifyTime
+    } from '@/ts/util/time';
     import shared from '@/ts/shared';
 
     shared.connect();
+    const playbackProgress = ref( 0 );
 
+    onMounted( () => {
+        setInterval( () => {
+            if ( !isPlaying.value ) return;
+
+            playbackTime.value = ( ( new Date().getTime() - startTime.value ) / 1000 ) + playbackOffset.value;
+            playbackProgress.value = playbackTime.value / song.value.duration;
+
+            if ( playbackTime.value > song.value.duration ) {
+                playbackOffset.value -= song.value.duration;
+
+                if ( currentQueueIdx.value < currentQueue.value.length - 1 )
+                    currentQueueIdx.value++;
+                else
+                    isPlaying.value = false;
+            }
+        }, 250 );
+    } );
     const song: ComputedRef<Song> = computed( () => {
         if ( currentQueueIdx.value >= 0 )
             return currentQueue.value[currentQueueIdx.value]!;
@@ -37,6 +65,15 @@
         <div>
             <div>
                 <CurrentSong v-model="song" />
+                <div class="time">
+                    <p class="current">
+                        {{ beautifyTime( playbackTime ) }}
+                    </p>
+                    <p class="duration">
+                        {{ beautifyTime( song.duration ) }}
+                    </p>
+                </div>
+                <ProgressBar v-model="playbackProgress" :disallow-move="true" />
             </div>
             <div>
                 <SharedQueue />