const http = require('http')

const WebSocket = require('ws')
const finalHttpHandler = require('finalhandler')
const serveStatic = require('serve-static')

const logger = require('./logger')

function getRemoteAddr (req) {
  return req.headers['cf-connecting-ip'] || req.headers['x-forwarded-for'] || req.connection.remoteAddress
}

class Server {
  constructor (clientSocketHandler) {
    this.createHttpServer()
    this.createWebSocketServer(clientSocketHandler)
  }

  createHttpServer () {
    const distServeStatic = serveStatic('dist/')
    const faviconsServeStatic = serveStatic('favicons/')

    this._http = http.createServer((req, res) => {
      logger.log('info', '%s requested: %s', getRemoteAddr(req), req.url)

      // Attempt to handle req using distServeStatic, otherwise fail over to faviconServeStatic
      // If faviconServeStatic fails, pass to finalHttpHandler to terminate
      distServeStatic(req, res, () => {
        faviconsServeStatic(req, res, finalHttpHandler(req, res))
      })
    })
  }

  createWebSocketServer (proxyClientSocketHandler) {
    this._wss = new WebSocket.Server({
      server: this._http
    })

    this._wss.on('connection', (client, req) => {
      logger.log('info', '%s connected, total clients: %d', getRemoteAddr(req), this.getConnectedClients())

      // Bind disconnect event for logging
      client.on('close', () => {
        logger.log('info', '%s disconnected, total clients: %d', getRemoteAddr(req), this.getConnectedClients())
      })

      // Pass client off to proxy handler
      proxyClientSocketHandler(client)
    })
  }

  listen (host, port) {
    this._http.listen(port, host)

    logger.log('info', 'Started on %s:%d', host, port)
  }

  broadcast (payload) {
    this._wss.clients.forEach(client => {
      if (client.readyState === WebSocket.OPEN) {
        client.send(payload)
      }
    })
  }

  getConnectedClients () {
    let count = 0
    this._wss.clients.forEach(client => {
      if (client.readyState === WebSocket.OPEN) {
        count++
      }
    })
    return count
  }
}

module.exports = Server