Smarter/more granular event handling

backend/src/MediaPlayer.ts

@@ -4,11 +4,21 @@ import { WebSocket } from "ws";
 import { getLinkPreview } from "link-preview-js";
 import { PlaylistItem, LinkMetadata } from './types';
 import { FavoritesStore } from "./FavoritesStore";
+
 interface PendingCommand {
     resolve: (value: any) => void;
     reject: (reason: any) => void;
 }
 
+enum UserEvent {
+    PlaylistUpdate      = "playlist_update",
+    NowPlayingUpdate    = "now_playing_update",
+    VolumeUpdate        = "volume_update",
+    FavoritesUpdate     = "favorites_update",
+    MetadataUpdate      = "metadata_update",
+    MPDUpdate           = "mpd_update",
+}
+
 export class MediaPlayer { 
     private playerProcess: ChildProcess;
     private socket: Socket;
@@ -43,7 +53,7 @@ export class MediaPlayer {
 
         this.favoritesStore = new FavoritesStore();
         this.favoritesStore.onFavoritesChanged = (favorites) => {
-            this.handleEvent("favorites_update", { favorites });
+            this.handleEvent(UserEvent.FavoritesUpdate, { favorites });
         };
     }
 
@@ -123,31 +133,31 @@ export class MediaPlayer {
     }
 
     public async play() {
-        return this.modify(() => this.writeCommand("set_property", ["pause", false]));
+        return this.modify(UserEvent.NowPlayingUpdate, () => this.writeCommand("set_property", ["pause", false]));
     }
 
     public async pause() {
-        return this.modify(() => this.writeCommand("set_property", ["pause", true]));
+        return this.modify(UserEvent.NowPlayingUpdate, () => this.writeCommand("set_property", ["pause", true]));
     }
 
     public async skip() {
-        return this.modify(() => this.writeCommand("playlist-next", []));
+        return this.modify(UserEvent.PlaylistUpdate, () => this.writeCommand("playlist-next", []));
     }
 
     public async skipTo(index: number) {
-        return this.modify(() => this.writeCommand("playlist-play-index", [index]));
+        return this.modify(UserEvent.PlaylistUpdate, () => this.writeCommand("playlist-play-index", [index]));
     }
 
     public async previous() {
-        return this.modify(() => this.writeCommand("playlist-prev", []));
+        return this.modify(UserEvent.PlaylistUpdate, () => this.writeCommand("playlist-prev", []));
     }
 
     public async deletePlaylistItem(index: number) {
-        return this.modify(() => this.writeCommand("playlist-remove", [index]));
+        return this.modify(UserEvent.PlaylistUpdate, () => this.writeCommand("playlist-remove", [index]));
     }
         
     public async setVolume(volume: number) {
-        return this.modify(() => this.writeCommand("set_property", ["volume", volume]));
+        return this.modify(UserEvent.VolumeUpdate, () => this.writeCommand("set_property", ["volume", volume]));
     }
 
     public subscribe(ws: WebSocket) {
@@ -175,18 +185,18 @@ export class MediaPlayer {
     }
 
     private async loadFile(url: string, mode: string) {
-        this.modify(() => this.writeCommand("loadfile", [url, mode]));
+        this.modify(UserEvent.PlaylistUpdate, () => this.writeCommand("loadfile", [url, mode]));
 
         this.fetchMetadataAndNotify(url).catch(error => {
             console.warn(`Failed to fetch metadata for ${url}:`, error);
         });
     }
 
-    private async modify<T>(func: () => Promise<T>): Promise<T> {
+    private async modify<T>(event: UserEvent, func: () => Promise<T>): Promise<T> {
         return func()
             .then((result) => {
                 // Notify all subscribers
-                this.handleEvent("user_modify", {});
+                this.handleEvent(event, {});
                 return result;
         });
     }
@@ -230,7 +240,7 @@ export class MediaPlayer {
             console.log(this.metadata.get(url));
             
             // Notify clients that metadata has been updated
-            this.handleEvent("metadata_update", {
+            this.handleEvent(UserEvent.MetadataUpdate, {
                 url,
                 metadata: this.metadata.get(url)
             });
@@ -272,7 +282,7 @@ export class MediaPlayer {
                             this.pendingCommands.delete(response.request_id);
                         }
                     } else if (response.event) {
-                        this.handleEvent(response.event, response);
+                        this.handleEvent(UserEvent.MPDUpdate, response);
                     } else {
                         console.log(response);
                     }

frontend/src/api/player.tsx

@@ -46,6 +46,15 @@ export interface SearchResponse {
   results: SearchResult[];
 }
 
+export enum ServerEvent {
+  PlaylistUpdate      = "playlist_update",
+  NowPlayingUpdate    = "now_playing_update",
+  VolumeUpdate        = "volume_update",
+  FavoritesUpdate     = "favorites_update",
+  MetadataUpdate      = "metadata_update",
+  MPDUpdate           = "mpd_update",
+}
+
 export const API = {
   async getPlaylist(): Promise<PlaylistItem[]> {
     const response = await fetch('/api/playlist');

frontend/src/components/App.tsx

@@ -3,9 +3,9 @@ import SongTable from './SongTable';
 import NowPlaying from './NowPlaying';
 import AddSongPanel from './AddSongPanel';
 import { TabView, Tab } from './TabView';
-import { API, getDisplayTitle, PlaylistItem } from '../api/player';
-import { useEventWebSocket } from '../hooks/useEventWebsocket';
+import { API, getDisplayTitle, PlaylistItem, ServerEvent } from '../api/player';
 import { FaMusic, FaHeart } from 'react-icons/fa';
+import useWebSocket from 'react-use-websocket';
 
 enum Tabs {
   Playlist = "playlist",
@@ -96,14 +96,17 @@ const App: React.FC = () => {
   }, []);
 
   const fetchNowPlaying = useCallback(async () => {
+    if (volumeSettingIsLocked) {
+      // We are actively changing the volume, which we do actually want to send events
+      // continuously to the server, but we don't want to refresh our state while doing that. 
+      return;
+    }
+
     const nowPlaying = await API.getNowPlaying();
     setNowPlayingSong(getDisplayTitle(nowPlaying.playingItem));
     setNowPlayingFileName(nowPlaying.playingItem.filename);
     setIsPlaying(!nowPlaying.isPaused);
-
-    if (!volumeSettingIsLocked) {
-      setVolume(nowPlaying.volume);
-    }
+    setVolume(nowPlaying.volume);
   }, [volumeSettingIsLocked]);
 
   const handleAddURL = async (url: string) => {
@@ -148,23 +151,41 @@ const App: React.FC = () => {
     await API.setVolume(volume);
   };
 
-  const handleWebSocketEvent = useCallback((event: any) => {
+  const handleWebSocketEvent = useCallback((message: MessageEvent) => {
+    const event = JSON.parse(message.data);
     switch (event.event) {
-      case 'user_modify':
-      case 'end-file':
-      case 'playback-restart':
-      case 'metadata_update':
+      case ServerEvent.PlaylistUpdate:
+      case ServerEvent.NowPlayingUpdate:
+      case ServerEvent.MetadataUpdate:
+      case ServerEvent.MPDUpdate:
         fetchPlaylist();
         fetchNowPlaying();
         break;
-      case 'favorites_update':
+      case ServerEvent.VolumeUpdate:
+        if (!volumeSettingIsLocked) {
+          fetchNowPlaying();
+        }
+
+        break;
+      case ServerEvent.FavoritesUpdate:
         fetchFavorites();
         break;
     }
   }, [fetchPlaylist, fetchNowPlaying, fetchFavorites]);
 
-  // Use the hook
-  useEventWebSocket(handleWebSocketEvent);
+  useWebSocket('/api/events', {
+    onOpen: () => {
+      console.log('WebSocket connected');
+    },
+    onClose: () => {
+      console.log('WebSocket disconnected');
+    },
+    onError: (error) => {
+      console.error('WebSocket error:', error);
+    },
+    onMessage: handleWebSocketEvent,
+    shouldReconnect: () => true,
+  });
 
   // Handle visibility changes
   useEffect(() => {

frontend/src/hooks/useEventWebsocket.ts

@@ -1,70 +0,0 @@
-import { useState, useEffect, useCallback } from 'react';
-import { API } from '../api/player';
-
-export const useEventWebSocket = (onEvent: (event: any) => void) => {
-  const [ws, setWs] = useState<WebSocket | null>(null);
-  const [wsReconnectTimeout, setWsReconnectTimeout] = useState<number | null>(null);
-
-  const connectWebSocket = useCallback(() => {
-    // Clear any existing reconnection timeout
-    if (wsReconnectTimeout) {
-      window.clearTimeout(wsReconnectTimeout);
-      setWsReconnectTimeout(null);
-    }
-
-    // Close existing websocket if it exists
-    if (ws) {
-      ws.close();
-    }
-
-    const websocket = API.subscribeToEvents(onEvent);
-    
-    websocket.addEventListener('close', () => {
-      console.log('WebSocket closed. Attempting to reconnect...');
-
-      // Attempt to reconnect after 2 seconds
-      const timeout = window.setTimeout(() => {
-        connectWebSocket();
-      }, 2000);
-
-      setWsReconnectTimeout(timeout);
-    });
-
-    websocket.addEventListener('error', (error) => {
-      console.error('WebSocket error:', error);
-      websocket.close();
-    });
-
-    setWs(websocket);
-  }, [wsReconnectTimeout, onEvent]);
-
-  // Check WebSocket health periodically
-  useEffect(() => {
-    const healthCheck = setInterval(() => {
-      if (!ws || ws.readyState === WebSocket.CLOSED || ws.readyState === WebSocket.CLOSING) {
-        console.log('WebSocket unhealthy, reconnecting...');
-        connectWebSocket();
-      }
-    }, 5000);
-
-    return () => {
-      clearInterval(healthCheck);
-    };
-  }, [ws, connectWebSocket]);
-
-  // Initial WebSocket connection
-  useEffect(() => {
-    connectWebSocket();
-
-    return () => {
-      if (ws) {
-        ws.close();
-      }
-      if (wsReconnectTimeout) {
-        window.clearTimeout(wsReconnectTimeout);
-      }
-    };
-  }, [connectWebSocket]);
-
-  return ws;
-}; 

package-lock.json

@@ -10,7 +10,10 @@
             "workspaces": [
                 "backend",
                 "frontend"
-            ]
+            ],
+            "dependencies": {
+                "react-use-websocket": "^4.13.0"
+            }
         },
         "backend": {
             "name": "mpvqueue",
@@ -4685,6 +4688,12 @@
                 "node": ">=0.10.0"
             }
         },
+        "node_modules/react-use-websocket": {
+            "version": "4.13.0",
+            "resolved": "https://registry.npmjs.org/react-use-websocket/-/react-use-websocket-4.13.0.tgz",
+            "integrity": "sha512-anMuVoV//g2N76Wxqvqjjo1X48r9Np3y1/gMl7arX84tAPXdy5R7sB5lO5hvCzQRYjqXwV8XMAiEBOUbyrZFrw==",
+            "license": "MIT"
+        },
         "node_modules/readdirp": {
             "version": "3.6.0",
             "resolved": "https://registry.npmjs.org/readdirp/-/readdirp-3.6.0.tgz",

package.json

@@ -8,5 +8,8 @@
     "workspaces": [
         "backend",
         "frontend"
-    ]
+    ],
+    "dependencies": {
+        "react-use-websocket": "^4.13.0"
+    }
 }