/**
 * Singleton WebSocket Service
 */
import { io, Socket } from "socket.io-client";

const BASE_URL = import.meta.env.DEV
  ? "http://localhost:5137"
  : (import.meta.env.VITE_WEBSOCKET_URL || window.location.origin);

const SOCKET_PATH = import.meta.env.VITE_WEBSOCKET_PATH || "/semblance_back/socket.io/";

let socket: Socket | null = null;
let currentRoom: string | null = null;
let coreListenersBound = false;

export function initSocket(getToken: () => string): Socket {
  if (socket) {
    socket.io.opts.auth = { token: getToken() };
    return socket;
  }

  socket = io(BASE_URL, {
    path: SOCKET_PATH,
    transports: ["websocket"],
    reconnection: true,
    autoConnect: false,
    timeout: 60000,
    pingInterval: 45000,
    pingTimeout: 120000,
    auth: (cb) => cb({ token: getToken() }),
  });

  socket.io.on("reconnect_attempt", () => {
    socket!.io.opts.auth = { token: getToken() };
  });

  socket.on("connect", () => {
    bindCoreListeners();
    if (currentRoom) rejoinRoom();
  });

  socket.onAny((event, ...args) => {
    const payload = args[0];

    switch (event) {
      case 'joined_focus_group':
        window.dispatchEvent(new CustomEvent("ws:joined_focus_group", { detail: payload }));
        break;
      case 'left_focus_group':
        window.dispatchEvent(new CustomEvent("ws:left_focus_group", { detail: payload }));
        break;
      case 'message_update':
        window.dispatchEvent(new CustomEvent("ws:message_update", { detail: payload }));
        break;
      case 'ai_status_update':
        window.dispatchEvent(new CustomEvent("ws:ai_status_update", { detail: payload }));
        break;
      case 'moderator_status_update':
        window.dispatchEvent(new CustomEvent("ws:moderator_status_update", { detail: payload }));
        break;
      case 'theme_update':
        window.dispatchEvent(new CustomEvent("ws:theme_update", { detail: payload }));
        break;
      case 'focus_group_update':
        window.dispatchEvent(new CustomEvent("ws:focus_group_update", { detail: payload }));
        break;
      case 'mode_event_update':
        window.dispatchEvent(new CustomEvent("ws:mode_event_update", { detail: payload }));
        break;
      case 'task_started':
        window.dispatchEvent(new CustomEvent("ws:task_started", { detail: payload }));
        break;
      case 'task_cancelled':
        window.dispatchEvent(new CustomEvent("ws:task_cancelled", { detail: payload }));
        break;
      case 'task_completed':
        window.dispatchEvent(new CustomEvent("ws:task_completed", { detail: payload }));
        break;
      case 'task_failed':
        window.dispatchEvent(new CustomEvent("ws:task_failed", { detail: payload }));
        break;
      case 'bulk_export_progress':
        window.dispatchEvent(new CustomEvent("ws:bulk_export_progress", { detail: payload }));
        break;
      case 'quota_warning':
        window.dispatchEvent(new CustomEvent("quota_warning", { detail: payload }));
        break;
      case 'quota_exceeded':
        window.dispatchEvent(new CustomEvent("quota_exceeded", { detail: payload }));
        break;
      case 'error':
        console.error('[WebSocket] Error:', payload);
        break;
      case 'auth_error':
        console.error('[WebSocket] Auth error');
        window.dispatchEvent(new CustomEvent("ws:auth_error", { detail: payload }));
        break;
    }
  });

  socket.on("connect_error", (error) => {
    console.error('[WebSocket] Connect error:', error.message);
  });

  socket.on("disconnect", (_reason) => {
  });

  return socket;
}

export function connectSocket() {
  if (socket && !socket.connected) {
    socket.connect();
  }
}

export function disconnectSocket() {
  if (socket) {
    socket.disconnect();
    currentRoom = null;
  }
}

export function joinFocusGroup(focus_group_id: string, ack?: (resp: any) => void) {
  currentRoom = focus_group_id;

  if (!socket?.connected) {
    connectSocket();
    setTimeout(() => {
      if (socket?.connected) {
        socket.emit("join_focus_group", { focus_group_id }, (resp: any) => ack?.(resp));
      }
    }, 1000);
    return;
  }

  socket.emit("join_focus_group", { focus_group_id }, (resp: any) => ack?.(resp));
}

export function leaveFocusGroup(focus_group_id: string) {
  if (currentRoom === focus_group_id) {
    currentRoom = null;
  }
  if (socket?.connected) {
    socket.emit("leave_focus_group", { focus_group_id });
  }
}

function rejoinRoom() {
  if (!socket?.connected || !currentRoom) return;
  socket.emit("join_focus_group", { focus_group_id: currentRoom });
}

function bindCoreListeners() {
  if (!socket) return;

  // Already bound — listeners are re-added via onAny, no need to duplicate
  if (coreListenersBound) return;

  socket.on("auth_error", (payload: any) => {
    console.error('[WebSocket] Auth error');
    window.dispatchEvent(new CustomEvent("ws:auth_error", { detail: payload }));
  });

  socket.on("error", (error: any) => {
    console.error('[WebSocket] Socket error:', error?.message || error);
  });

  coreListenersBound = true;
}

export function getSocket() {
  return socket;
}

export function getSocketId() {
  return socket?.id;
}

export function isConnected() {
  return socket?.connected ?? false;
}