/*
 * Copyright 2018 Allan Wang
 *
 * 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.
 *
 * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package com.pitchedapps.frost.activities

import android.content.Intent
import android.content.res.ColorStateList
import android.graphics.Color
import android.net.Uri
import android.os.Bundle
import android.view.View
import android.widget.ImageView
import androidx.customview.widget.ViewDragHelper
import ca.allanwang.kau.internal.KauBaseActivity
import ca.allanwang.kau.logging.KauLoggerExtension
import ca.allanwang.kau.utils.adjustAlpha
import ca.allanwang.kau.utils.colorToForeground
import ca.allanwang.kau.utils.fadeIn
import ca.allanwang.kau.utils.fadeOut
import ca.allanwang.kau.utils.gone
import ca.allanwang.kau.utils.invisible
import ca.allanwang.kau.utils.isHidden
import ca.allanwang.kau.utils.isVisible
import ca.allanwang.kau.utils.materialDialog
import ca.allanwang.kau.utils.scaleXY
import ca.allanwang.kau.utils.setIcon
import ca.allanwang.kau.utils.tint
import ca.allanwang.kau.utils.toast
import ca.allanwang.kau.utils.withAlpha
import ca.allanwang.kau.utils.withMinAlpha
import com.github.piasy.biv.loader.ImageLoader
import com.github.piasy.biv.view.ImageShownCallback
import com.google.android.material.bottomsheet.BottomSheetBehavior
import com.google.android.material.floatingactionbutton.FloatingActionButton
import com.mikepenz.iconics.typeface.IIcon
import com.mikepenz.iconics.typeface.library.googlematerial.GoogleMaterial
import com.pitchedapps.frost.R
import com.pitchedapps.frost.databinding.ActivityImageBinding
import com.pitchedapps.frost.facebook.requests.getFullSizedImageUrl
import com.pitchedapps.frost.injectors.ThemeProvider
import com.pitchedapps.frost.prefs.Prefs
import com.pitchedapps.frost.utils.ARG_COOKIE
import com.pitchedapps.frost.utils.ARG_IMAGE_URL
import com.pitchedapps.frost.utils.ARG_TEXT
import com.pitchedapps.frost.utils.ActivityThemer
import com.pitchedapps.frost.utils.frostDownload
import com.pitchedapps.frost.utils.frostSnackbar
import com.pitchedapps.frost.utils.frostUriFromFile
import com.pitchedapps.frost.utils.isIndirectImageUrl
import com.pitchedapps.frost.utils.logFrostEvent
import dagger.hilt.android.AndroidEntryPoint
import kotlinx.coroutines.CoroutineExceptionHandler
import kotlinx.coroutines.Deferred
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.async
import kotlinx.coroutines.launch
import java.io.File
import java.io.FileNotFoundException
import javax.inject.Inject
import kotlin.math.abs
import kotlin.math.max

/**
 * Created by Allan Wang on 2017-07-15.
 */
@AndroidEntryPoint
class ImageActivity : KauBaseActivity() {

    @Inject
    lateinit var activityThemer: ActivityThemer

    @Inject
    lateinit var prefs: Prefs

    @Inject
    lateinit var themeProvider: ThemeProvider

    @Volatile
    internal var errorRef: Throwable? = null

    /**
     * Reference to the temporary file path
     */
    internal val tempFile: File? get() = binding.imagePhoto.currentImageFile

    private lateinit var dragHelper: ViewDragHelper

    private val cookie: String? by lazy { intent.getStringExtra(ARG_COOKIE) }

    val imageUrl: String by lazy { intent.getStringExtra(ARG_IMAGE_URL)?.trim('"') ?: "" }

    private lateinit var trueImageUrl: Deferred<String>

    private val imageText: String? by lazy { intent.getStringExtra(ARG_TEXT) }

    lateinit var binding: ActivityImageBinding
    private var bottomBehavior: BottomSheetBehavior<View>? = null

    private val baseBackgroundColor: Int
        get() = if (prefs.blackMediaBg) Color.BLACK
        else themeProvider.bgColor.withMinAlpha(235)

    private fun loadError(e: Throwable) {
        if (e.message?.contains("<!DOCTYPE html>") == true) {
            applicationContext.toast(R.string.image_not_found)
            finish()
            return
        }
        errorRef = e
        e.logFrostEvent("Image load error")
        with(binding) {
            if (imageProgress.isVisible)
                imageProgress.fadeOut()
        }
        tempFile?.delete()
        binding.error.fadeIn()
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        if (imageUrl.isEmpty()) {
            return finish()
        }
        L.i { "Displaying image" }
        trueImageUrl = async(Dispatchers.IO) {
            val result = if (!imageUrl.isIndirectImageUrl) imageUrl
            else cookie?.getFullSizedImageUrl(imageUrl) ?: imageUrl
            if (result != imageUrl)
                L.v { "Launching image with true url $result" }
            else
                L.v { "Launching image with url $result" }
            result
        }
        binding = ActivityImageBinding.inflate(layoutInflater)
        setContentView(binding.root)
        binding.init()
        launch(CoroutineExceptionHandler { _, throwable -> loadError(throwable) }) {
            binding.showImage(trueImageUrl.await())
        }
    }

    private fun ActivityImageBinding.showImage(url: String) {
        imagePhoto.showImage(Uri.parse(url))
        imagePhoto.setImageShownCallback(object : ImageShownCallback {
            override fun onThumbnailShown() {}

            override fun onMainImageShown() {
                imageProgress.fadeOut()
                imagePhoto.animate().alpha(1f).scaleXY(1f).start()
            }
        })
    }

    private fun ActivityImageBinding.init() {
        imageContainer.setBackgroundColor(baseBackgroundColor)
        toolbar.setBackgroundColor(baseBackgroundColor)
        this@ImageActivity.imageText.also { text ->
            if (text.isNullOrBlank()) {
                imageText.gone()
            } else {
                imageText.setTextColor(if (prefs.blackMediaBg) Color.WHITE else themeProvider.textColor)
                imageText.setBackgroundColor(
                    baseBackgroundColor.colorToForeground(0.2f).withAlpha(255)
                )
                imageText.text = text
                bottomBehavior = BottomSheetBehavior.from<View>(imageText).apply {
                    addBottomSheetCallback(object : BottomSheetBehavior.BottomSheetCallback() {
                        override fun onSlide(bottomSheet: View, slideOffset: Float) {
                            imageText.alpha = slideOffset / 2 + 0.5f
                        }

                        override fun onStateChanged(bottomSheet: View, newState: Int) {
                            // No op
                        }
                    })
                }
                imageText.bringToFront()
            }
        }
        val foregroundTint = if (prefs.blackMediaBg) Color.WHITE else themeProvider.accentColor

        fun ImageView.setState(state: FabStates) {
            setIcon(state.iicon, color = foregroundTint, sizeDp = 24)
            setOnClickListener { state.onClick(this@ImageActivity) }
        }

        imageProgress.tint(foregroundTint)
        error.apply {
            invisible()
            setState(FabStates.ERROR)
        }
        download.apply {
            setState(FabStates.DOWNLOAD)
        }
        share.apply {
            setState(FabStates.SHARE)
        }

        imagePhoto.setImageLoaderCallback(object : ImageLoader.Callback {
            override fun onCacheHit(imageType: Int, image: File?) {}

            override fun onCacheMiss(imageType: Int, image: File?) {}

            override fun onStart() {}

            override fun onProgress(progress: Int) {}

            override fun onFinish() {}

            override fun onSuccess(image: File) {}

            override fun onFail(error: Exception) {
                loadError(error)
            }
        })

        activityThemer.setFrostColors {
            themeWindow = false
        }
        dragHelper = ViewDragHelper.create(imageDrag, ViewDragCallback()).apply {
            setEdgeTrackingEnabled(ViewDragHelper.EDGE_TOP or ViewDragHelper.EDGE_BOTTOM)
        }
        imageDrag.dragHelper = dragHelper
        imageDrag.viewToIgnore = imageText
    }

    private inner class ViewDragCallback : ViewDragHelper.Callback() {
        private var scrollPercent: Float = 0f
        private var scrollThreshold = 0.5f
        private var scrollToTop = false

        override fun tryCaptureView(view: View, i: Int): Boolean {
            L.d { "Try capture ${view.id} $i ${binding.imagePhoto.id} ${binding.imageText.id}" }
            return view === binding.imagePhoto
        }

        override fun getViewHorizontalDragRange(child: View): Int = 0

        override fun getViewVerticalDragRange(child: View): Int = child.height

        override fun onViewPositionChanged(
            changedView: View,
            left: Int,
            top: Int,
            dx: Int,
            dy: Int
        ) {
            super.onViewPositionChanged(changedView, left, top, dx, dy)
            with(binding) {
                // make sure that we are using the proper axis
                scrollPercent = abs(top.toFloat() / imageContainer.height)
                scrollToTop = top < 0
                val multiplier = max(1f - scrollPercent, 0f)

                toolbar.alpha = multiplier
                bottomBehavior?.also {
                    imageText.alpha =
                        multiplier * (if (it.state == BottomSheetBehavior.STATE_COLLAPSED) 0.5f else 1f)
                }
                imageContainer.setBackgroundColor(baseBackgroundColor.adjustAlpha(multiplier))

                if (scrollPercent >= 1) {
                    if (!isFinishing) {
                        finish()
                        overridePendingTransition(0, 0)
                    }
                }
            }
        }

        override fun onViewReleased(releasedChild: View, xvel: Float, yvel: Float) {
            val overScrolled = scrollPercent > scrollThreshold
            val maxOffset = releasedChild.height + 10
            val finalTop = when {
                scrollToTop && (overScrolled || yvel < -dragHelper.minVelocity) -> -maxOffset
                !scrollToTop && (overScrolled || yvel > dragHelper.minVelocity) -> maxOffset
                else -> 0
            }
            dragHelper.settleCapturedViewAt(0, finalTop)
            binding.imageDrag.invalidate()
        }

        override fun clampViewPositionHorizontal(child: View, left: Int, dx: Int): Int = 0

        override fun clampViewPositionVertical(child: View, top: Int, dy: Int): Int = top
    }

    internal suspend fun saveImage() {
        frostDownload(cookie = cookie, url = trueImageUrl.await())
    }

    companion object {
        private val L = KauLoggerExtension("Image", com.pitchedapps.frost.utils.L)
    }
}

internal enum class FabStates(
    val iicon: IIcon,
    val iconColorProvider: (ThemeProvider) -> Int = { it.iconColor },
    val backgroundTint: Int = Int.MAX_VALUE
) {
    ERROR(GoogleMaterial.Icon.gmd_error, { Color.WHITE }, Color.RED) {
        override fun onClick(activity: ImageActivity) {
            val err =
                activity.errorRef?.takeIf { it !is FileNotFoundException && it.message != "Image failed to decode using JPEG decoder" }
                    ?: return
            activity.materialDialog {
                title(R.string.kau_error)
                message(text = err.message ?: err.javaClass.name)
            }
        }
    },
    NOTHING(GoogleMaterial.Icon.gmd_adjust) {
        override fun onClick(activity: ImageActivity) {}
    },
    DOWNLOAD(GoogleMaterial.Icon.gmd_file_download) {
        override fun onClick(activity: ImageActivity) {
            activity.launch {
                activity.binding.download.fadeOut()
                activity.saveImage()
            }
        }
    },
    SHARE(GoogleMaterial.Icon.gmd_share) {
        override fun onClick(activity: ImageActivity) {
            val file = activity.tempFile ?: return
            try {
                val photoURI = activity.frostUriFromFile(file)
                val intent = Intent(Intent.ACTION_SEND).apply {
                    flags = Intent.FLAG_ACTIVITY_NEW_TASK
                    putExtra(Intent.EXTRA_STREAM, photoURI)
                    type = "image/png"
                }
                activity.startActivity(intent)
            } catch (e: Exception) {
                activity.errorRef = e
                e.logFrostEvent("Image share failed")
                activity.frostSnackbar(R.string.image_share_failed, activity.themeProvider)
            }
        }
    };

    /**
     * Change the fab look
     * If it's in view, give it some animations
     *
     * TODO investigate what is wrong with fadeScaleTransition
     *
     * https://github.com/AllanWang/KAU/issues/184
     *
     */
    fun update(fab: FloatingActionButton, themeProvider: ThemeProvider) {
        val tint =
            if (backgroundTint != Int.MAX_VALUE) backgroundTint else themeProvider.accentColor
        val iconColor = iconColorProvider(themeProvider)
        if (fab.isHidden) {
            fab.setIcon(iicon, color = iconColor)
            fab.backgroundTintList = ColorStateList.valueOf(tint)
            fab.show()
        } else {
            fab.hide(object : FloatingActionButton.OnVisibilityChangedListener() {
                override fun onHidden(fab: FloatingActionButton) {
                    fab.setIcon(iicon, color = iconColor)
                    fab.show()
                }
            })
        }
    }

    abstract fun onClick(activity: ImageActivity)
}