import { connectedUsers } from './state';
import { ConnectedUser } from './types';
import { broadcastToServer, findUserByOderId } from './broadcast';

interface WsMessage {
  [key: string]: unknown;
  type: string;
}

/** Sends the current user list for a given server to a single connected user. */
function sendServerUsers(user: ConnectedUser, serverId: string): void {
  const users = Array.from(connectedUsers.values())
    .filter(cu => cu.serverIds.has(serverId) && cu.oderId !== user.oderId && cu.displayName)
    .map(cu => ({ oderId: cu.oderId, displayName: cu.displayName ?? 'Anonymous' }));

  user.ws.send(JSON.stringify({ type: 'server_users', serverId, users }));
}

function handleIdentify(user: ConnectedUser, message: WsMessage, connectionId: string): void {
  user.oderId = String(message['oderId'] || connectionId);
  user.displayName = String(message['displayName'] || 'Anonymous');
  connectedUsers.set(connectionId, user);
  console.log(`User identified: ${user.displayName} (${user.oderId})`);
}

function handleJoinServer(user: ConnectedUser, message: WsMessage, connectionId: string): void {
  const sid = String(message['serverId']);
  const isNew = !user.serverIds.has(sid);

  user.serverIds.add(sid);
  user.viewedServerId = sid;
  connectedUsers.set(connectionId, user);
  console.log(`User ${user.displayName ?? 'Anonymous'} (${user.oderId}) joined server ${sid} (new=${isNew})`);

  sendServerUsers(user, sid);

  if (isNew) {
    broadcastToServer(sid, {
      type: 'user_joined',
      oderId: user.oderId,
      displayName: user.displayName ?? 'Anonymous',
      serverId: sid
    }, user.oderId);
  }
}

function handleViewServer(user: ConnectedUser, message: WsMessage, connectionId: string): void {
  const viewSid = String(message['serverId']);

  user.viewedServerId = viewSid;
  connectedUsers.set(connectionId, user);
  console.log(`User ${user.displayName ?? 'Anonymous'} (${user.oderId}) viewing server ${viewSid}`);

  sendServerUsers(user, viewSid);
}

function handleLeaveServer(user: ConnectedUser, message: WsMessage, connectionId: string): void {
  const leaveSid = (message['serverId'] as string | undefined) ?? user.viewedServerId;

  if (!leaveSid)
    return;

  user.serverIds.delete(leaveSid);

  if (user.viewedServerId === leaveSid)
    user.viewedServerId = undefined;

  connectedUsers.set(connectionId, user);

  broadcastToServer(leaveSid, {
    type: 'user_left',
    oderId: user.oderId,
    displayName: user.displayName ?? 'Anonymous',
    serverId: leaveSid
  }, user.oderId);
}

function forwardRtcMessage(user: ConnectedUser, message: WsMessage): void {
  const targetUserId = String(message['targetUserId'] || '');

  console.log(`Forwarding ${message.type} from ${user.oderId} to ${targetUserId}`);

  const targetUser = findUserByOderId(targetUserId);

  if (targetUser) {
    targetUser.ws.send(JSON.stringify({ ...message, fromUserId: user.oderId }));
    console.log(`Successfully forwarded ${message.type} to ${targetUserId}`);
  } else {
    console.log(
      `Target user ${targetUserId} not found. Connected users:`,
      Array.from(connectedUsers.values()).map(cu => ({ oderId: cu.oderId, displayName: cu.displayName }))
    );
  }
}

function handleChatMessage(user: ConnectedUser, message: WsMessage): void {
  const chatSid = (message['serverId'] as string | undefined) ?? user.viewedServerId;

  if (chatSid && user.serverIds.has(chatSid)) {
    broadcastToServer(chatSid, {
      type: 'chat_message',
      serverId: chatSid,
      message: message['message'],
      senderId: user.oderId,
      senderName: user.displayName,
      timestamp: Date.now()
    });
  }
}

function handleTyping(user: ConnectedUser, message: WsMessage): void {
  const typingSid = (message['serverId'] as string | undefined) ?? user.viewedServerId;

  if (typingSid && user.serverIds.has(typingSid)) {
    broadcastToServer(typingSid, {
      type: 'user_typing',
      serverId: typingSid,
      oderId: user.oderId,
      displayName: user.displayName
    }, user.oderId);
  }
}

export function handleWebSocketMessage(connectionId: string, message: WsMessage): void {
  const user = connectedUsers.get(connectionId);

  if (!user)
    return;

  switch (message.type) {
    case 'identify':
      handleIdentify(user, message, connectionId);
      break;

    case 'join_server':
      handleJoinServer(user, message, connectionId);
      break;

    case 'view_server':
      handleViewServer(user, message, connectionId);
      break;

    case 'leave_server':
      handleLeaveServer(user, message, connectionId);
      break;

    case 'offer':
    case 'answer':
    case 'ice_candidate':
      forwardRtcMessage(user, message);
      break;

    case 'chat_message':
      handleChatMessage(user, message);
      break;

    case 'typing':
      handleTyping(user, message);
      break;

    default:
      console.log('Unknown message type:', message.type);
  }
}