/** Complex channel used by UWB ranging. */
public class UwbComplexChannel {

    @FiraParams.UwbChannel private final int mChannel;
    @FiraParams.UwbPreambleCodeIndex private final int mPreambleIndex;
}

// The coroutineScope responsible for handling uwb ranging.
// This will be initialized when startRanging is called.

var job: Job?

// A code snippet that initiates uwb ranging for a controlee.
suspend fun startRanging() {

    // Get the ranging parameter of a partnering controller using an OOB
    // mechanism of choice.
    val partnerAddress : Pair<UwbAddress, UwbComplexChannel> = listenForPartnersAddress()

    // Create the ranging parameters.
    val partnerParameters = RangingParameters(
        uwbConfigType = UwbRangingParamters.UWB_CONFIG_ID_1,
        // SessionKeyInfo is used to encrypt the ranging session.
        sessionKeyInfo = null,
        complexChannel = partnerAddress.second,
        peerDevices = listOf(UwbDevice.createForAddress(partnerAddress.first)),
        //自动更新率，屏幕常亮时为240ms周期，灭默认为4s
        updateRateType = UwbRangingParamters.RANGING_UPDATE_RATE_AUTOMATIC
    )

    // Initiate a session that will be valid for a single ranging session.
    val clientSession = uwbManager.clientSessionScope()

    // Share the localAddress of the current session to the partner device.
    broadcastMyParameters(clientSession.localAddress)
    val sessionFlow = clientSession.prepareSession(partnerParameters)
    
    // Start a coroutine(协程） scope that initiates ranging.
    CoroutineScope(Dispatchers.Main.immediate).launch {
        sessionFlow.collect {
            when(it) {
                is RangingResultPosition -> doSomethingWithPosition(it.position)
                is RangingResultPeerDisconnected -> peerDisconnected(it)
            }
        }
    }
}

// A code snippet that cancels uwb ranging.
fun cancelRanging() {
    // Canceling the CoroutineScope will stop the ranging.
    job?.let {
        it.cancel()
    }
}