const HERMES_WS_URL = 'ws://143.198.27.163/api/world/ws';

export class WebSocketClient {
  constructor(url = HERMES_WS_URL) {
    this.url = url;
    this.reconnectAttempts = 0;
    this.maxReconnectAttempts = 10;
    this.reconnectBaseDelay = 1000;
    this.maxReconnectDelay = 30000;
    this.socket = null;
    this.connected = false;
    this.reconnectTimeout = null;
    this.messageQueue = [];
  }

  connect() {
    if (this.socket && (this.socket.readyState === WebSocket.OPEN || this.socket.readyState === WebSocket.CONNECTING)) {
      return;
    }

    try {
      this.socket = new WebSocket(this.url);
    } catch (err) {
      console.error('[hermes] WebSocket construction failed:', err);
      this._scheduleReconnect();
      return;
    }

    this.socket.onopen = () => {
      console.log('[hermes] Connected to Hermes gateway');
      this.connected = true;
      this.reconnectAttempts = 0;
      this.messageQueue.forEach(msg => this._send(msg));
      this.messageQueue = [];
      window.dispatchEvent(new CustomEvent('ws-connected', { detail: { url: this.url } }));
    };

    this.socket.onmessage = (event) => {
      let data;
      try {
        data = JSON.parse(event.data);
      } catch (err) {
        console.warn('[hermes] Unparseable message:', event.data);
        return;
      }
      this._route(data);
    };

    this.socket.onclose = (event) => {
      this.connected = false;
      this.socket = null;
      console.warn(`[hermes] Connection closed (code=${event.code})`);
      window.dispatchEvent(new CustomEvent('ws-disconnected', { detail: { code: event.code } }));
      this._scheduleReconnect();
    };

    this.socket.onerror = () => {
      // onclose fires after onerror; logging here would be redundant noise
      console.warn('[hermes] WebSocket error — waiting for close event');
    };
  }

  _route(data) {
    switch (data.type) {
      case 'chat':
      case 'chat-message':
        window.dispatchEvent(new CustomEvent('chat-message', { detail: data }));
        break;

      case 'status-update':
        window.dispatchEvent(new CustomEvent('status-update', { detail: data }));
        break;

      case 'pr-notification':
        window.dispatchEvent(new CustomEvent('pr-notification', { detail: data }));
        break;

      case 'player-joined':
        window.dispatchEvent(new CustomEvent('player-joined', { detail: data }));
        break;

      case 'player-left':
        window.dispatchEvent(new CustomEvent('player-left', { detail: data }));
        break;

      default:
        console.debug('[hermes] Unhandled message type:', data.type, data);
    }
  }

  _scheduleReconnect() {
    if (this.reconnectAttempts >= this.maxReconnectAttempts) {
      console.warn('[hermes] Max reconnection attempts reached — giving up');
      window.dispatchEvent(new CustomEvent('ws-failed'));
      return;
    }

    const delay = Math.min(
      this.reconnectBaseDelay * Math.pow(2, this.reconnectAttempts),
      this.maxReconnectDelay
    );
    console.log(`[hermes] Reconnecting in ${delay}ms (attempt ${this.reconnectAttempts + 1}/${this.maxReconnectAttempts})`);
    this.reconnectTimeout = setTimeout(() => {
      this.reconnectAttempts++;
      this.connect();
    }, delay);
  }

  _send(message) {
    this.socket.send(JSON.stringify(message));
  }

  send(message) {
    if (this.connected && this.socket && this.socket.readyState === WebSocket.OPEN) {
      this._send(message);
    } else {
      this.messageQueue.push(message);
    }
  }

  disconnect() {
    if (this.reconnectTimeout) {
      clearTimeout(this.reconnectTimeout);
      this.reconnectTimeout = null;
    }
    this.maxReconnectAttempts = 0; // prevent auto-reconnect after intentional disconnect
    if (this.socket) {
      this.socket.close();
      this.socket = null;
    }
  }
}

export const wsClient = new WebSocketClient();