package com.pitchedapps.frost.activities

import android.content.Context
import android.content.Intent
import android.content.res.ColorStateList
import android.graphics.Bitmap
import android.graphics.Color
import android.graphics.drawable.Drawable
import android.net.Uri
import android.os.Bundle
import android.os.Environment
import android.support.design.widget.FloatingActionButton
import android.view.View
import android.view.ViewGroup
import android.widget.ProgressBar
import android.widget.TextView
import ca.allanwang.kau.internal.KauBaseActivity
import ca.allanwang.kau.logging.KauLoggerExtension
import ca.allanwang.kau.mediapicker.scanMedia
import ca.allanwang.kau.permissions.PERMISSION_WRITE_EXTERNAL_STORAGE
import ca.allanwang.kau.permissions.kauRequestPermissions
import ca.allanwang.kau.utils.*
import com.bumptech.glide.Glide
import com.bumptech.glide.RequestManager
import com.bumptech.glide.request.target.BaseTarget
import com.bumptech.glide.request.target.SizeReadyCallback
import com.bumptech.glide.request.target.Target
import com.bumptech.glide.request.transition.Transition
import com.davemorrissey.labs.subscaleview.ImageSource
import com.davemorrissey.labs.subscaleview.SubsamplingScaleImageView
import com.mikepenz.google_material_typeface_library.GoogleMaterial
import com.mikepenz.iconics.typeface.IIcon
import com.pitchedapps.frost.R
import com.pitchedapps.frost.facebook.requests.call
import com.pitchedapps.frost.utils.*
import com.sothree.slidinguppanel.SlidingUpPanelLayout
import okhttp3.Request
import org.jetbrains.anko.activityUiThreadWithContext
import org.jetbrains.anko.doAsync
import java.io.File
import java.io.IOException
import java.text.SimpleDateFormat
import java.util.*

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

    val progress: ProgressBar by bindView(R.id.image_progress)
    val container: ViewGroup by bindView(R.id.image_container)
    val panel: SlidingUpPanelLayout? by bindOptionalView(R.id.image_panel)
    val photo: SubsamplingScaleImageView by bindView(R.id.image_photo)
    val caption: TextView? by bindOptionalView(R.id.image_text)
    val fab: FloatingActionButton by bindView(R.id.image_fab)
    var errorRef: Throwable? = null

    private val tempDir: File by lazy { File(cacheDir, IMAGE_FOLDER) }

    /**
     * Reference to the temporary file path
     * Should be nonnull if the image is successfully loaded
     * As this is temporary, the image is deleted upon exit
     */
    internal var tempFile: File? = null
    /**
     * Reference to path for downloaded image
     * Nonnull once the image is downloaded by the user
     */
    internal var savedFile: File? = null
    /**
     * Indicator for fab's click result
     */
    internal var fabAction: FabStates = FabStates.NOTHING
        set(value) {
            if (field == value) return
            field = value
            value.update(fab)
        }

    companion object {
        /**
         * Cache folder to store images
         * Linked to the uri provider
         */
        private const val IMAGE_FOLDER = "images"
        private const val TIME_FORMAT = "yyyyMMdd_HHmmss"
        private const val IMG_TAG = "Frost"
        private const val IMG_EXTENSION = ".png"
        private val L = KauLoggerExtension("Image", com.pitchedapps.frost.utils.L)
    }

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

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

    private val glide: RequestManager by lazy { Glide.with(this) }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        intent?.extras ?: return finish()
        L.i { "Displaying image" }
        val layout = if (!text.isNullOrBlank()) R.layout.activity_image else R.layout.activity_image_textless
        setContentView(layout)
        container.setBackgroundColor(Prefs.bgColor.withMinAlpha(222))
        caption?.setTextColor(Prefs.textColor)
        caption?.setBackgroundColor(Prefs.bgColor.colorToForeground(0.2f).withAlpha(255))
        caption?.text = text
        progress.tint(Prefs.accentColor)
        panel?.addPanelSlideListener(object : SlidingUpPanelLayout.SimplePanelSlideListener() {
            override fun onPanelSlide(panel: View, slideOffset: Float) {
                if (slideOffset == 0f && !fab.isShown) fab.show()
                else if (slideOffset != 0f && fab.isShown) fab.hide()
                caption?.alpha = slideOffset / 2 + 0.5f
            }
        })
        fab.setOnClickListener { fabAction.onClick(this) }
        photo.setOnImageEventListener(object : SubsamplingScaleImageView.DefaultOnImageEventListener() {
            override fun onImageLoadError(e: Exception?) {
                errorRef = e
                e.logFrostAnswers("Image load error")
                imageCallback(null, false)
            }
        })
        glide.asBitmap().load(imageUrl).into(PhotoTarget(this::imageCallback))
        setFrostColors {
            themeWindow = false
        }
    }

    /**
     * Callback to add image to view
     * [resource] is guaranteed to be nonnull when [success] is true
     * and null when it is false
     */
    private fun imageCallback(resource: Bitmap?, success: Boolean) {
        if (progress.isVisible) progress.fadeOut()
        if (success) {
            saveTempImage(resource!!, {
                if (it == null) {
                    imageCallback(null, false)
                } else {
                    photo.setImage(ImageSource.uri(it))
                    fabAction = FabStates.DOWNLOAD
                    photo.animate().alpha(1f).scaleXY(1f).withEndAction(fab::show).start()
                }
            })
        } else {
            fabAction = FabStates.ERROR
            fab.show()
        }
    }

    /**
     * Bitmap load handler
     */
    class PhotoTarget(val callback: (resource: Bitmap?, success: Boolean) -> Unit) : BaseTarget<Bitmap>() {

        override fun removeCallback(cb: SizeReadyCallback?) {}

        override fun onResourceReady(resource: Bitmap, transition: Transition<in Bitmap>?) =
                callback(resource, true)

        override fun onLoadFailed(errorDrawable: Drawable?) =
                callback(null, false)

        override fun getSize(cb: SizeReadyCallback) =
                cb.onSizeReady(Target.SIZE_ORIGINAL, Target.SIZE_ORIGINAL)

    }

    private fun saveTempImage(resource: Bitmap, callback: (uri: Uri?) -> Unit) {
        var photoFile: File? = null
        try {
            photoFile = createPrivateMediaFile()
        } catch (e: IOException) {
            errorRef = e
            logImage(e)
        } finally {
            if (photoFile == null) {
                callback(null)
            } else {
                tempFile = photoFile
                L.d { "Temp image path ${tempFile?.absolutePath}" }
                // File created; proceed with request
                val photoURI = frostUriFromFile(photoFile)
                photoFile.outputStream().use { resource.compress(Bitmap.CompressFormat.PNG, 100, it) }
                callback(photoURI)
            }
        }
    }

    private fun logImage(e: Exception?) {
        if (!Prefs.analytics) return
        val error = e ?: IOException("$imageUrl failed to load")
        L.e(error) { "$imageUrl failed to load" }
    }

    @Throws(IOException::class)
    private fun createPrivateMediaFile(): File {
        val timeStamp = SimpleDateFormat(TIME_FORMAT, Locale.getDefault()).format(Date())
        val imageFileName = "${IMG_TAG}_${timeStamp}_"
        if (!tempDir.exists())
            tempDir.mkdirs()
        return File.createTempFile(imageFileName, IMG_EXTENSION, tempDir)
    }

    @Throws(IOException::class)
    private fun createPublicMediaFile(): File {
        val timeStamp = SimpleDateFormat(TIME_FORMAT, Locale.getDefault()).format(Date())
        val imageFileName = "${IMG_TAG}_${timeStamp}_"
        val storageDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES)
        val frostDir = File(storageDir, IMG_TAG)
        if (!frostDir.exists()) frostDir.mkdirs()
        return File.createTempFile(imageFileName, IMG_EXTENSION, frostDir)
    }

    @Throws(IOException::class)
    private fun downloadImageTo(file: File) {
        val body = Request.Builder()
                .url(imageUrl)
                .get()
                .call()
                .execute()
                .body() ?: throw IOException("Failed to retrieve image body")
        body.byteStream().use { input ->
            file.outputStream().use { output ->
                input.copyTo(output)
            }
        }
    }

    internal fun saveImage() {
        kauRequestPermissions(PERMISSION_WRITE_EXTERNAL_STORAGE) { granted, _ ->
            L.d { "Download image callback granted: $granted" }
            if (granted) {
                doAsync {
                    val destination = createPublicMediaFile()
                    var success = true
                    try {
                        val temp = tempFile
                        if (temp != null)
                            temp.copyTo(destination, true)
                        else
                            downloadImageTo(destination)
                    } catch (e: Exception) {
                        errorRef = e
                        success = false
                    } finally {
                        L.d { "Download image async finished: $success" }
                        if (success) {
                            scanMedia(destination)
                            savedFile = destination
                        } else {
                            try {
                                destination.delete()
                            } catch (ignore: Exception) {
                            }
                        }
                        activityUiThreadWithContext {
                            val text = if (success) R.string.image_download_success else R.string.image_download_fail
                            frostSnackbar(text)
                            if (success) fabAction = FabStates.SHARE
                        }
                    }
                }
            }
        }
    }

    override fun onDestroy() {
        tempFile = null
        tempDir.deleteRecursively()
        L.d { "Closing $localClassName" }
        super.onDestroy()
    }
}

internal enum class FabStates(val iicon: IIcon, val iconColor: Int = Prefs.iconColor, val backgroundTint: Int = Int.MAX_VALUE) {
    ERROR(GoogleMaterial.Icon.gmd_error, Color.WHITE, Color.RED) {
        override fun onClick(activity: ImageActivity) {
            activity.materialDialogThemed {
                title(R.string.kau_error)
                content(R.string.bad_image_overlay)
                positiveText(R.string.kau_yes)
                onPositive { _, _ ->
                    if (activity.errorRef != null)
                        L.e(activity.errorRef) { "ImageActivity error report" }
                    activity.sendFrostEmail(R.string.debug_image_link_subject) {
                        addItem("Url", activity.imageUrl)
                        addItem("Message", activity.errorRef?.message ?: "Null")
                    }
                }
                negativeText(R.string.kau_no)
            }
        }
    },
    NOTHING(GoogleMaterial.Icon.gmd_adjust) {
        override fun onClick(activity: ImageActivity) {}
    },
    DOWNLOAD(GoogleMaterial.Icon.gmd_file_download) {
        override fun onClick(activity: ImageActivity) = activity.saveImage()
    },
    SHARE(GoogleMaterial.Icon.gmd_share) {
        override fun onClick(activity: ImageActivity) {
            try {
                val photoURI = activity.frostUriFromFile(activity.savedFile!!)
                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.logFrostAnswers("Image share failed")
                activity.frostSnackbar(R.string.image_share_failed)
            }
        }
    };

    /**
     * Change the fab look
     * If it's in view, give it some animations
     */
    fun update(fab: FloatingActionButton) {
        val tint = if (backgroundTint != Int.MAX_VALUE) backgroundTint else Prefs.accentColor
        if (fab.isHidden) {
            fab.setIcon(iicon, color = iconColor)
            fab.backgroundTintList = ColorStateList.valueOf(tint)
            fab.show()
        } else {
            fab.fadeScaleTransition {
                setIcon(iicon, color = iconColor)
                backgroundTintList = ColorStateList.valueOf(tint)
            }
        }
    }

    abstract fun onClick(activity: ImageActivity)

}