abstract class UseCase<in P, R>(private val ioDispatcher: CoroutineDispatcher) {
    suspend operator fun invoke(parameters: P): Result<R> {
        return withContext(ioDispatcher) {
            return@withContext executeNow(parameters)
        }
    }
    /**
     * 同步執行程式，回傳 [Result]
     */
    suspend fun executeNow(parameters: P): Result<R> {
        return try {
            execute(parameters)
        } catch (e: Exception) {
            Result.Error(e)
        }
    }
    /**
     * override 此方法並把邏輯寫在這裡
     */
    @Throws(RuntimeException::class)
    protected abstract suspend fun execute(parameters: P): Result<R>
}
suspend operator fun <R> UseCase<Unit, R>.invoke(): Result<R> = this(Unit)