Android VoIP Development with Kotlin: PJSIP, ConnectionService & Push

class SipService : Service(), PjSipObserver {
  private lateinit var endpoint: Endpoint
  private lateinit var account: SipAccount

  override fun onCreate() {
    super.onCreate()
    endpoint = Endpoint()
    endpoint.libCreate()
    val epConfig = EpConfig()
    epConfig.logConfig.level = 4u
    endpoint.libInit(epConfig)

    val tcfg = TransportConfig()
    tcfg.port = 5060u
    endpoint.transportCreate(pjsip_transport_type_e.PJSIP_TRANSPORT_UDP, tcfg)
    endpoint.libStart()

    val acfg = AccountConfig()
    acfg.idUri = "sip:[email protected]"
    acfg.regConfig.registrarUri = "sip:example.com"
    acfg.sipConfig.proxies.add("<sip:example.com;lr>")
    val authCreds = AuthCredInfo("digest", "*", "alice", 0, "secret")
    acfg.sipConfig.authCreds.add(authCreds)

    account = SipAccount(this)
    account.create(acfg)
  }

  override fun onIncomingCall(prm: OnIncomingCallParam) {
    // Notify via ConnectionService
    startActivity(IncomingCallActivity.intent(this, prm.callId))
  }
}