feat: initial JaniChat messenger — PWA, WebSocket, admin panel

frontend/src/api/ws.ts

@@ -0,0 +1,70 @@
+type Handler = (payload: any) => void;
+
+class WsClient {
+  private ws: WebSocket | null = null;
+  private handlers = new Map<string, Handler[]>();
+  private reconnectTimer: ReturnType<typeof setTimeout> | null = null;
+  private token: string | null = null;
+
+  connect(token: string) {
+    this.token = token;
+    const wsBase = import.meta.env.VITE_WS_URL || `${location.protocol === 'https:' ? 'wss' : 'ws'}://${location.host}`;
+    this.ws = new WebSocket(`${wsBase}/ws?token=${token}`);
+
+    this.ws.onopen = () => {
+      if (this.reconnectTimer) {
+        clearTimeout(this.reconnectTimer);
+        this.reconnectTimer = null;
+      }
+      this.emit('connected', null);
+    };
+
+    this.ws.onmessage = (event) => {
+      try {
+        const { type, payload } = JSON.parse(event.data);
+        const hs = this.handlers.get(type) || [];
+        hs.forEach(h => h(payload));
+      } catch {}
+    };
+
+    this.ws.onclose = () => {
+      this.emit('disconnected', null);
+      this.reconnectTimer = setTimeout(() => {
+        if (this.token) this.connect(this.token);
+      }, 3000);
+    };
+
+    this.ws.onerror = () => {
+      this.ws?.close();
+    };
+  }
+
+  on(type: string, handler: Handler) {
+    if (!this.handlers.has(type)) this.handlers.set(type, []);
+    this.handlers.get(type)!.push(handler);
+    return () => {
+      const hs = this.handlers.get(type) || [];
+      this.handlers.set(type, hs.filter(h => h !== handler));
+    };
+  }
+
+  private emit(type: string, payload: any) {
+    const hs = this.handlers.get(type) || [];
+    hs.forEach(h => h(payload));
+  }
+
+  send(type: string, payload: any) {
+    if (this.ws?.readyState === WebSocket.OPEN) {
+      this.ws.send(JSON.stringify({ type, payload }));
+    }
+  }
+
+  disconnect() {
+    this.token = null;
+    if (this.reconnectTimer) clearTimeout(this.reconnectTimer);
+    this.ws?.close();
+    this.ws = null;
+  }
+}
+
+export const wsClient = new WsClient();