import android.os.Handler
import android.os.Looper

class PendingProgressController @JvmOverloads constructor(private val progress: Progress,
                                                          private val showDelay: Long = 300L,
                                                          private val minShowTime: Long = 500L) : Progress {

    private var startTime: Long = -1
    private var postedHide = false
    private var postedShow = false
    private var dismissed = false

    private val delayedHide = Runnable {
        postedHide = false
        startTime = -1
        progress.hide()
    }

    private val delayedShow = Runnable {
        postedShow = false
        if (!dismissed) {
            startTime = System.currentTimeMillis()
            progress.show()
        }
    }

    override fun show() {
        startTime = -1
        dismissed = false
        MAIN_THREAD_HANDLER.removeCallbacks(delayedHide)
        postedHide = false
        if (!postedShow) {
            MAIN_THREAD_HANDLER.postDelayed(delayedShow, showDelay)
            postedShow = true
        }
    }

    override fun hide() {
        dismissed = true
        MAIN_THREAD_HANDLER.removeCallbacks(delayedShow)
        postedShow = false
        val diff = System.currentTimeMillis() - startTime
        if (diff >= minShowTime || startTime == -1L) {
            progress.hide()
        } else {
            if (!postedHide) {
                MAIN_THREAD_HANDLER.postDelayed(delayedHide, minShowTime - diff)
                postedHide = true
            }
        }
    }

    companion object {
        private val MAIN_THREAD_HANDLER = Handler(Looper.getMainLooper())
    }
}