let data = {
  clients: {},

  // Key: Controller
  // Value: Controlee
  // Music is played on Value's device.
  control: {}
}

function getSocketByDevice (devid) {
  for (let id in data.clients) {
    let sock = data.clients[i]
    if (sock.device && sock.device === devid) {
      return sock
    }
  }

  return null
}

function getControlling (sockid) {
  for (let id in data.control) {
    let cl = data.control[id]
    if (cl === sockid) return id
  }

  return null
}

function start (io) {
  io.on('connection', function (socket) {
    let sockid = socket.id

    socket.on('auth', function (device) {
      if (getSocketByDevice(device) != null) {
        return socket.emit('cerr', {error: 'devexists', code: 0})
      }

      socket.device = device
      data.clients[sockid] = socket
    })

    socket.on('req:devs', function () {
      let devices = []

      for (let i in data.clients) {
        let cl = data.clients[i]
        if (cl.device === socket.device) continue
        devices.push(devices)
      }

      socket.emit('res:devs', devices)
    })

    // Controller wants to take control of Controlee
    socket.on('ctrl:connect', function (ctrlee) {
      let dev = getSocketByDevice(ctrlee)
      if (!dev) return socket.emit('cerr', {error: 'devnull', code: 1})

      // Device is already controlling/being controlled
      if (data.control[sockid] || getControlling(dev.id)) return socket.emit('cerr', {error: 'devctrl', code: 2})

      dev.emit('ctrl:connect', { device: socket.device })
      socket.emit('targ:success', { device: ctrlee })
    })

    // Disconnect
    socket.on('ctrl:disconnect', function (ctrlee) {
      let id, ctrl
      if (getControlling(sockid)) {
        // If this is a controlee, disconnect from controller
        id = getControlling(sockid)
        ctrl = data.clients[id]

        delete data.control[id]
      } else if (data.control[sockid]) {
        // If this is a controller, disconnect from controlee
        id = data.control[sockid]
        ctrl = data.clients[id]

        delete data.control[sockid]
      }

      if (!ctrl) return

      ctrl.emit('targ:disconnect', {})
    })

    let directpass = ['track', 'pause', 'seek', 'volume', 'mute', 'queue', 'req:queue', 'res:queue']
    for (let i in directpass) {
      let syn = 'sync:' + directpass[i]

      // Set pause/play state
      // Sent from controlee to controller
      socket.on(syn, function (data) {
        let ctrl

        if (getControlling(sockid)) {
          // If this is a controlee, send to controller
          ctrl = data.clients[getControlling(sockid)]
        } else if (data.control[sockid]) {
          // If this is a controller, send to controlee
          ctrl = data.clients[data.control[sockid]]
        }

        ctrl && ctrl.emit('set:' + directpass[i], data)
      })
    }

    // Synchronize timestamp
    socket.on('sync:time', function (data) {
      if (!getControlling(sockid)) return
      let ctrl = data.clients[getControlling(sockid)]
      ctrl && ctrl.emit('sync:time', data)
    })

    socket.on('disconnect', function () {
      if (data.clients[sockid]) {
        let dev = data.clients[sockid]

        // Controller loses connection
        // Emit to controlee
        if (data.control[sockid]) {
          let clt = data.clients[sockid]
          clt && clt.emit('ctrl:disconnect', {})

        // Controlee loses connection
        // Emit to controller
        } else if (getControlling(sockid)) {
          let clt = data.clients[getControlling(sockid)]
          clt && clt.emit('targ:disconnect', {})
        }

        delete data.clients[sockid]
      }
    })
  })
}

module.exports = { start }