subject-two/entry/src/main/ets/utils/UdpUtils.ets

import socket from '@ohos.net.socket'

type DealMethod = (value: ArrayBuffer) => string

class UdpClient {
  private localIp: string = ''
  private localIpPort: string = ''
  private oppositeIp: string = ''
  private oppositeIpPort: string = ''
  private messageEvents: Array<Function> = []
  private udp: socket.UDPSocket = null
  private disconnectEvents: Array<Function> = []
  private dealMethod: DealMethod

  private dealMessage() {
    this.udp?.on("message", value => {
      let result = this?.dealMethod(value.message)
      this.messageEvents.forEach(cb => {
        cb(result)
      })
    })
  }

  init(udpLocalIp: string, udpLocalIpPort: string, udpOppositeIp: string, udpOppositeIpPort: string) {
    this.localIp = udpLocalIp
    this.oppositeIp = udpOppositeIp
    this.localIpPort = udpLocalIpPort
    this.oppositeIpPort = udpOppositeIpPort
    this.udp = socket.constructUDPSocketInstance();
  }

  bindUdp(): Promise<void> {
    return this.udp.bind({ address: this.localIp, port: parseInt(this.localIpPort), family: 1 }).then(() => {
      try {
        this.dealMessage()
        return Promise.resolve()
      } catch (e) {
        return Promise.reject(e)
      }
    })
  }

  async reBind() {
    await this.close()
    this.udp = socket.constructUDPSocketInstance();
    await this.bindUdp()
  }

  close(): Promise<void> {
    return this.udp?.close()
  }

  setDealMethod(fun: DealMethod) {
    this.dealMethod = fun
  }

  onMessage(callback: Function) {
    this.messageEvents.push(callback)
  }

  onDisconnect(callback: Function) {
    this.disconnectEvents.push(callback)
  }

  sendMsg(data: string): Promise<void> {
    return this.udp?.getState().then(() => {
      return this.udp.send({
        data,
        address: { address: this.oppositeIp, port: parseInt(this.oppositeIpPort), family: 1 }
      })
    })
  }
}

export const objUDPClient = new UdpClient()

export const centerUDPClient = new UdpClient()

export const lightUDPClient = new UdpClient()

export const judgeUDPClient = new UdpClient()