/* Copyright 2017 Andrew Dawson
 *
 * This file is a part of Tusky.
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the
 * GNU General Public License as published by the Free Software Foundation; either version 3 of the
 * License, or (at your option) any later version.
 *
 * Tusky is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
 * Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with Tusky; if not,
 * see <http://www.gnu.org/licenses>. */

package com.keylesspalace.tusky.fragment

import android.animation.Animator
import android.animation.AnimatorListenerAdapter
import android.annotation.SuppressLint
import android.content.Context
import android.os.Bundle
import android.os.Handler
import android.os.Looper
import android.text.method.ScrollingMovementMethod
import android.view.GestureDetector
import android.view.KeyEvent
import android.view.LayoutInflater
import android.view.MotionEvent
import android.view.View
import android.view.ViewGroup
import android.widget.MediaController
import androidx.core.view.GestureDetectorCompat
import com.keylesspalace.tusky.ViewMediaActivity
import com.keylesspalace.tusky.databinding.FragmentViewVideoBinding
import com.keylesspalace.tusky.entity.Attachment
import com.keylesspalace.tusky.util.hide
import com.keylesspalace.tusky.util.visible
import com.keylesspalace.tusky.view.ExposedPlayPauseVideoView
import kotlin.math.abs

class ViewVideoFragment : ViewMediaFragment() {
    interface VideoActionsListener {
        fun onDismiss()
    }

    private var _binding: FragmentViewVideoBinding? = null
    private val binding get() = _binding!!

    private lateinit var videoActionsListener: VideoActionsListener
    private lateinit var toolbar: View
    private val handler = Handler(Looper.getMainLooper())
    private val hideToolbar = Runnable {
        // Hoist toolbar hiding to activity so it can track state across different fragments
        // This is explicitly stored as runnable so that we pass it to the handler later for cancellation
        mediaActivity.onPhotoTap()
        mediaController.hide()
    }
    private lateinit var mediaActivity: ViewMediaActivity
    private lateinit var mediaController: MediaController
    private var isAudio = false

    companion object {
        private const val TOOLBAR_HIDE_DELAY_MS = 3000L
    }

    override fun onAttach(context: Context) {
        super.onAttach(context)
        videoActionsListener = context as VideoActionsListener
    }

    override fun onResume() {
        super.onResume()

        if (_binding != null) {
            if (mediaActivity.isToolbarVisible && !isAudio) {
                hideToolbarAfterDelay(TOOLBAR_HIDE_DELAY_MS)
            }
            binding.videoView.start()
        }
    }

    override fun onPause() {
        super.onPause()

        if (_binding != null) {
            handler.removeCallbacks(hideToolbar)
            binding.videoView.pause()
            mediaController.hide()
        }
    }

    @SuppressLint("ClickableViewAccessibility")
    override fun setupMediaView(
        url: String,
        previewUrl: String?,
        description: String?,
        showingDescription: Boolean
    ) {
        binding.mediaDescription.text = description
        binding.mediaDescription.visible(showingDescription)
        binding.mediaDescription.movementMethod = ScrollingMovementMethod()

        // Ensure the description is visible over the video
        binding.mediaDescription.elevation = binding.videoView.elevation + 1

        binding.videoView.transitionName = url
        binding.videoView.setVideoPath(url)
        mediaController = object : MediaController(mediaActivity) {
            override fun show(timeout: Int) {
                // We're doing manual auto-close management.
                // Also, take focus back from the pause button so we can use the back button.
                super.show(0)
                mediaController.requestFocus()
            }

            override fun dispatchKeyEvent(event: KeyEvent?): Boolean {
                if (event?.keyCode == KeyEvent.KEYCODE_BACK) {
                    if (event.action == KeyEvent.ACTION_UP) {
                        hide()
                        activity?.supportFinishAfterTransition()
                    }
                    return true
                }
                return super.dispatchKeyEvent(event)
            }
        }

        mediaController.setMediaPlayer(binding.videoView)
        binding.videoView.setMediaController(mediaController)
        binding.videoView.requestFocus()
        binding.videoView.setPlayPauseListener(object : ExposedPlayPauseVideoView.PlayPauseListener {
            override fun onPlay() {
                if (!isAudio) {
                    hideToolbarAfterDelay(TOOLBAR_HIDE_DELAY_MS)
                }
            }

            override fun onPause() {
                if (!isAudio) {
                    handler.removeCallbacks(hideToolbar)
                }
            }
        })
        binding.videoView.setOnPreparedListener { mp ->
            val containerWidth = binding.videoContainer.measuredWidth.toFloat()
            val containerHeight = binding.videoContainer.measuredHeight.toFloat()
            val videoWidth = mp.videoWidth.toFloat()
            val videoHeight = mp.videoHeight.toFloat()

            if (isAudio) {
                binding.videoView.layoutParams.height = 1
                binding.videoView.layoutParams.width = ViewGroup.LayoutParams.MATCH_PARENT
            } else if (containerWidth / containerHeight > videoWidth / videoHeight) {
                binding.videoView.layoutParams.height = ViewGroup.LayoutParams.MATCH_PARENT
                binding.videoView.layoutParams.width = ViewGroup.LayoutParams.WRAP_CONTENT
            } else {
                binding.videoView.layoutParams.height = ViewGroup.LayoutParams.WRAP_CONTENT
                binding.videoView.layoutParams.width = ViewGroup.LayoutParams.MATCH_PARENT
            }

            // Wait until the media is loaded before accepting taps as we don't want toolbar to
            // be hidden until then.
            binding.videoView.setOnTouchListener { _, _ ->
                mediaActivity.onPhotoTap()
                false
            }

            // Audio doesn't cause the controller to show automatically
            if (isAudio) {
                mediaController.show()
            }

            binding.progressBar.hide()
            mp.isLooping = true
        }

        if (requireArguments().getBoolean(ARG_START_POSTPONED_TRANSITION)) {
            mediaActivity.onBringUp()
        }
    }

    private fun hideToolbarAfterDelay(delayMilliseconds: Long) {
        handler.postDelayed(hideToolbar, delayMilliseconds)
    }

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
        mediaActivity = activity as ViewMediaActivity
        toolbar = mediaActivity.toolbar
        _binding = FragmentViewVideoBinding.inflate(inflater, container, false)
        return binding.root
    }

    @SuppressLint("ClickableViewAccessibility")
    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        val attachment = arguments?.getParcelable<Attachment>(ARG_ATTACHMENT)
            ?: throw IllegalArgumentException("attachment has to be set")

        val url = attachment.url
        isAudio = attachment.type == Attachment.Type.AUDIO

        val gestureDetector = GestureDetectorCompat(
            requireContext(),
            object : GestureDetector.SimpleOnGestureListener() {
                override fun onDown(event: MotionEvent): Boolean {
                    return true
                }

                override fun onFling(
                    e1: MotionEvent,
                    e2: MotionEvent,
                    velocityX: Float,
                    velocityY: Float
                ): Boolean {
                    if (abs(velocityY) > abs(velocityX)) {
                        videoActionsListener.onDismiss()
                        return true
                    }
                    return false
                }
            }
        )

        var lastY = 0f
        binding.root.setOnTouchListener { _, event ->
            if (event.action == MotionEvent.ACTION_DOWN) {
                lastY = event.rawY
            } else if (event.pointerCount == 1 && event.action == MotionEvent.ACTION_MOVE) {
                val diff = event.rawY - lastY
                if (binding.videoView.translationY != 0f || abs(diff) > 40) {
                    binding.videoView.translationY += diff
                    val scale = (-abs(binding.videoView.translationY) / 720 + 1).coerceAtLeast(0.5f)
                    binding.videoView.scaleY = scale
                    binding.videoView.scaleX = scale
                    lastY = event.rawY
                    return@setOnTouchListener true
                }
            } else if (event.action == MotionEvent.ACTION_UP || event.action == MotionEvent.ACTION_CANCEL) {
                if (abs(binding.videoView.translationY) > 180) {
                    videoActionsListener.onDismiss()
                } else {
                    binding.videoView.animate().translationY(0f).scaleX(1f).scaleY(1f).start()
                }
            }

            gestureDetector.onTouchEvent(event)
        }

        finalizeViewSetup(url, attachment.previewUrl, attachment.description)
    }

    override fun onToolbarVisibilityChange(visible: Boolean) {
        if (_binding == null || !userVisibleHint) {
            return
        }

        isDescriptionVisible = showingDescription && visible
        val alpha = if (isDescriptionVisible) 1.0f else 0.0f
        if (isDescriptionVisible) {
            // If to be visible, need to make visible immediately and animate alpha
            binding.mediaDescription.alpha = 0.0f
            binding.mediaDescription.visible(isDescriptionVisible)
        }

        binding.mediaDescription.animate().alpha(alpha)
            .setListener(object : AnimatorListenerAdapter() {
                override fun onAnimationEnd(animation: Animator) {
                    if (_binding != null) {
                        binding.mediaDescription.visible(isDescriptionVisible)
                    }
                    animation.removeListener(this)
                }
            })
            .start()

        if (visible && binding.videoView.isPlaying && !isAudio) {
            hideToolbarAfterDelay(TOOLBAR_HIDE_DELAY_MS)
        } else {
            handler.removeCallbacks(hideToolbar)
        }
    }

    override fun onTransitionEnd() {
    }

    override fun onDestroyView() {
        super.onDestroyView()
        _binding = null
    }
}