request.kt

abstract class Request(val target: Target = HostTarget) {

    /**
     * Some requests require a device serial to be passed to the request itself by means of <host-prefix>
     * @see https://android.googlesource.com/platform/system/core/+/refs/heads/master/adb/SERVICES.TXT
     */
    abstract fun serialize(): ByteArray

    open suspend fun handshake(readChannel: AndroidReadChannel, writeChannel: AndroidWriteChannel) {
        val request = serialize()
        writeChannel.write(request)
        val response = readChannel.read()
        if (!response.okay) {
            log.warn { "adb server rejected command ${String(request, Const.DEFAULT_TRANSPORT_ENCODING)}" }
            throw RequestRejectedException(response.message ?: "no message received")
        }
    }

    protected fun createBaseRequest(request: String): ByteArray {
        val fullRequest = target.serialize() + request
        return String.format("%04X%s", fullRequest.length, fullRequest)
            .toByteArray(Const.DEFAULT_TRANSPORT_ENCODING)
    }
}