frontend: Finish interactivity

frontend/src/api/player.tsx

@@ -0,0 +1,82 @@
+export interface NowPlayingResponse {
+  success: boolean;
+  nowPlaying: string;
+  isPaused: boolean;
+  volume: number;
+  isIdle: boolean;
+  currentFile: string;
+}
+
+export interface PlaylistItem {
+  filename: string;
+  title: string | null;
+  id: number;
+  playing: boolean | null;
+}
+
+export const API = {
+  async getPlaylist(): Promise<PlaylistItem[]> {
+    const response = await fetch('/api/playlist');
+    return response.json();
+  },
+  
+  async addToPlaylist(url: string): Promise<void> {
+    await fetch('/api/playlist', {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify({ url }),
+    });
+  },
+  
+  async removeFromPlaylist(index: number): Promise<void> {
+    await fetch(`/api/playlist/${index}`, {
+      method: 'DELETE',
+    });
+  },
+  
+  async play(): Promise<void> {
+    await fetch('/api/play', { method: 'POST' });
+  },
+  
+  async pause(): Promise<void> {
+    await fetch('/api/pause', { method: 'POST' });
+  },
+  
+  async skip(): Promise<void> {
+    await fetch('/api/skip', { method: 'POST' });
+  },
+
+  async skipTo(index: number): Promise<void> {
+    await fetch(`/api/skip/${index}`, { method: 'POST' });
+  },
+  
+  async previous(): Promise<void> {
+    await fetch('/api/previous', { method: 'POST' });
+  },
+  
+  async getNowPlaying(): Promise<NowPlayingResponse> {
+    const response = await fetch('/api/nowplaying');
+    return response.json();
+  },
+  
+  async setVolume(volume: number): Promise<void> {
+    await fetch('/api/volume', {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify({ volume }),
+    });
+  },
+  
+  subscribeToEvents(onMessage: (event: any) => void): WebSocket {
+    const ws = new WebSocket(`ws://${window.location.host}/api/events`);
+    ws.onmessage = (event) => {
+      onMessage(JSON.parse(event.data));
+    };
+
+    return ws;
+  }
+};