// external imports
import * as WebSocket from 'ws';
import * as jwt from 'jsonwebtoken';
import * as url from 'url';

// internal imports
const app = require('./config/app');
const logger = require('./logger');

import ClientManager from './clientManager';
import ChannelManager from './channelManager';
import PublicClient from './clients/types/publicClient';
import PrivateClient from './clients/types/privateClient';
import CustomClient from './clients/types/customClient';

const wss = new WebSocket.Server({ maxPayload: 250000, port: app.port });
const clientManager = new ClientManager();
const channelManager = new ChannelManager();

function connectionManager() {
  wss.on('connection', (ws: WebSocket, request: any, args: string) => {
    const result = JSON.parse(validateJWT(request));

    if (result.error) {
      ws.send(`Unable to validate JWT, please try again or contact support...`);
      ws.close();
    } else {
      const data = result.data;
      let client: PublicClient|PrivateClient|CustomClient|null;
      logger.accessLog.info(`Client Connected: ${data.user_id}`);

      if (!channelManager.channelExists(data.channel)) channelManager.createChannel(data);

      if (clientManager.clientExists(data.user_id)) {
        client = clientManager.getClient(data.user_id);

        if (client != null) {
          client.replaceWebSocket(ws);
        }
      } else {
        client = clientManager.addClient(data, channelManager, ws);
      }

      if (client != null) channelManager.addClientToChannel(client, data.channel);

      logger.accessLog.info(`Purging empty channels...`);
      channelManager.purgeEmptyChannels();

      ws.send(`Hi there, welcome to braid, Measures Web Socket server. Connecting all our services!\nYou are currently in channel: ${data.channel}`);
    }
  });
}

function validateJWT(request: any) {
  try {
    const query = url.parse(request.url, true).query;
    const token = query.token || (app.environment === 'development' ? app.devToken : '');
    return JSON.stringify(jwt.verify(token, app.secret, app.signOptions));
  } catch (e) {
    console.log(e);
    return JSON.stringify({error: e});
  }
}

function startServer() {
  connectionManager();
}

startServer();

module.exports = {
  clientManager,
  channelManager,
  connectionManager
};