package io.heckel.ntfy.msg

import android.app.*
import android.content.ActivityNotFoundException
import android.content.BroadcastReceiver
import android.content.Context
import android.content.Intent
import android.media.RingtoneManager
import android.net.Uri
import android.os.Build
import android.os.Bundle
import android.widget.Toast
import androidx.core.app.NotificationCompat
import androidx.core.content.ContextCompat
import io.heckel.ntfy.R
import io.heckel.ntfy.db.*
import io.heckel.ntfy.db.Notification
import io.heckel.ntfy.ui.Colors
import io.heckel.ntfy.ui.DetailActivity
import io.heckel.ntfy.ui.MainActivity
import io.heckel.ntfy.util.*
import java.util.*


class NotificationService(val context: Context) {
    private val notificationManager = context.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager

    fun display(subscription: Subscription, notification: Notification) {
        Log.d(TAG, "Displaying notification $notification")
        displayInternal(subscription, notification)
    }

    fun update(subscription: Subscription, notification: Notification) {
        val active = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            notificationManager.activeNotifications.find { it.id == notification.notificationId } != null
        } else {
            true
        }
        if (active) {
            Log.d(TAG, "Updating notification $notification")
            displayInternal(subscription, notification, update = true)
        }
    }

    fun cancel(notification: Notification) {
        if (notification.notificationId != 0) {
            Log.d(TAG, "Cancelling notification ${notification.id}: ${decodeMessage(notification)}")
            notificationManager.cancel(notification.notificationId)
        }
    }

    fun cancel(notificationId: Int) {
        if (notificationId != 0) {
            Log.d(TAG, "Cancelling notification ${notificationId}")
            notificationManager.cancel(notificationId)
        }
    }

    fun createNotificationChannels() {
        (1..5).forEach { priority -> maybeCreateNotificationChannel(priority) }
    }

    private fun displayInternal(subscription: Subscription, notification: Notification, update: Boolean = false) {
        val title = formatTitle(subscription, notification)
        val channelId = toChannelId(notification.priority)
        val builder = NotificationCompat.Builder(context, channelId)
            .setSmallIcon(R.drawable.ic_notification)
            .setColor(ContextCompat.getColor(context, Colors.notificationIcon(context)))
            .setContentTitle(title)
            .setOnlyAlertOnce(true) // Do not vibrate or play sound if already showing (updates!)
            .setAutoCancel(true) // Cancel when notification is clicked
        setStyleAndText(builder, subscription, notification) // Preview picture or big text style
        setClickAction(builder, subscription, notification)
        maybeSetSound(builder, update)
        maybeSetProgress(builder, notification)
        maybeAddOpenAction(builder, notification)
        maybeAddBrowseAction(builder, notification)
        maybeAddDownloadAction(builder, notification)
        maybeAddCancelAction(builder, notification)
        maybeAddUserActions(builder, notification)

        maybeCreateNotificationChannel(notification.priority)
        notificationManager.notify(notification.notificationId, builder.build())
    }

    private fun maybeSetSound(builder: NotificationCompat.Builder, update: Boolean) {
        if (!update) {
            val defaultSoundUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION)
            builder.setSound(defaultSoundUri)
        } else {
            builder.setSound(null)
        }
    }

    private fun setStyleAndText(builder: NotificationCompat.Builder, subscription: Subscription, notification: Notification) {
        val contentUri = notification.attachment?.contentUri
        val isSupportedImage = supportedImage(notification.attachment?.type)
        val subscriptionIcon = if (subscription.icon != null) subscription.icon.readBitmapFromUriOrNull(context) else null
        val notificationIcon = if (notification.icon != null) notification.icon.contentUri?.readBitmapFromUriOrNull(context) else null
        val largeIcon = notificationIcon ?: subscriptionIcon
        if (contentUri != null && isSupportedImage) {
            try {
                val attachmentBitmap = contentUri.readBitmapFromUri(context)
                builder
                    .setContentText(maybeAppendActionErrors(formatMessage(notification), notification))
                    .setLargeIcon(attachmentBitmap)
                    .setStyle(NotificationCompat.BigPictureStyle()
                        .bigPicture(attachmentBitmap)
                        .bigLargeIcon(largeIcon)) // May be null
            } catch (_: Exception) {
                val message = maybeAppendActionErrors(formatMessageMaybeWithAttachmentInfos(notification), notification)
                builder
                    .setContentText(message)
                    .setStyle(NotificationCompat.BigTextStyle().bigText(message))
            }
        } else {
            val message = maybeAppendActionErrors(formatMessageMaybeWithAttachmentInfos(notification), notification)
            builder
                .setContentText(message)
                .setStyle(NotificationCompat.BigTextStyle().bigText(message))
                .setLargeIcon(largeIcon) // May be null
        }
    }

    private fun formatMessageMaybeWithAttachmentInfos(notification: Notification): String {
        val message = formatMessage(notification)
        val attachment = notification.attachment ?: return message
        val attachmentInfos = if (attachment.size != null) {
            "${attachment.name}, ${formatBytes(attachment.size)}"
        } else {
            attachment.name
        }
        if (attachment.progress in 0..99) {
            return context.getString(R.string.notification_popup_file_downloading, attachmentInfos, attachment.progress, message)
        }
        if (attachment.progress == ATTACHMENT_PROGRESS_DONE) {
            return context.getString(R.string.notification_popup_file_download_successful, message, attachmentInfos)
        }
        if (attachment.progress == ATTACHMENT_PROGRESS_FAILED) {
            return context.getString(R.string.notification_popup_file_download_failed, message, attachmentInfos)
        }
        return context.getString(R.string.notification_popup_file, message, attachmentInfos)
    }

    private fun setClickAction(builder: NotificationCompat.Builder, subscription: Subscription, notification: Notification) {
        if (notification.click == "") {
            builder.setContentIntent(detailActivityIntent(subscription))
        } else {
            try {
                val uri = Uri.parse(notification.click)
                val viewIntent = PendingIntent.getActivity(context, Random().nextInt(), Intent(Intent.ACTION_VIEW, uri), PendingIntent.FLAG_IMMUTABLE)
                builder.setContentIntent(viewIntent)
            } catch (e: Exception) {
                builder.setContentIntent(detailActivityIntent(subscription))
            }
        }
    }

    private fun maybeSetProgress(builder: NotificationCompat.Builder, notification: Notification) {
        val progress = notification.attachment?.progress
        if (progress in 0..99) {
            builder.setProgress(100, progress!!, false)
        } else {
            builder.setProgress(0, 0, false) // Remove progress bar
        }
    }

    private fun maybeAddOpenAction(builder: NotificationCompat.Builder, notification: Notification) {
        if (notification.attachment?.contentUri != null) {
            val contentUri = Uri.parse(notification.attachment.contentUri)
            val intent = Intent(Intent.ACTION_VIEW, contentUri).apply {
                setDataAndType(contentUri, notification.attachment.type ?: "application/octet-stream") // Required for Android <= P
                addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
            }
            val pendingIntent = PendingIntent.getActivity(context, Random().nextInt(), intent, PendingIntent.FLAG_IMMUTABLE)
            builder.addAction(NotificationCompat.Action.Builder(0, context.getString(R.string.notification_popup_action_open), pendingIntent).build())
        }
    }

    private fun maybeAddBrowseAction(builder: NotificationCompat.Builder, notification: Notification) {
        if (notification.attachment?.contentUri != null) {
            val intent = Intent(android.app.DownloadManager.ACTION_VIEW_DOWNLOADS).apply {
                addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
            }
            val pendingIntent = PendingIntent.getActivity(context, Random().nextInt(), intent, PendingIntent.FLAG_IMMUTABLE)
            builder.addAction(NotificationCompat.Action.Builder(0, context.getString(R.string.notification_popup_action_browse), pendingIntent).build())
        }
    }

    private fun maybeAddDownloadAction(builder: NotificationCompat.Builder, notification: Notification) {
        if (notification.attachment?.contentUri == null && listOf(ATTACHMENT_PROGRESS_NONE, ATTACHMENT_PROGRESS_FAILED).contains(notification.attachment?.progress)) {
            val intent = Intent(context, UserActionBroadcastReceiver::class.java).apply {
                putExtra(BROADCAST_EXTRA_TYPE, BROADCAST_TYPE_DOWNLOAD_START)
                putExtra(BROADCAST_EXTRA_NOTIFICATION_ID, notification.id)
            }
            val pendingIntent = PendingIntent.getBroadcast(context, Random().nextInt(), intent, PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE)
            builder.addAction(NotificationCompat.Action.Builder(0, context.getString(R.string.notification_popup_action_download), pendingIntent).build())
        }
    }

    private fun maybeAddCancelAction(builder: NotificationCompat.Builder, notification: Notification) {
        if (notification.attachment?.contentUri == null && notification.attachment?.progress in 0..99) {
            val intent = Intent(context, UserActionBroadcastReceiver::class.java).apply {
                putExtra(BROADCAST_EXTRA_TYPE, BROADCAST_TYPE_DOWNLOAD_CANCEL)
                putExtra(BROADCAST_EXTRA_NOTIFICATION_ID, notification.id)
            }
            val pendingIntent = PendingIntent.getBroadcast(context, Random().nextInt(), intent, PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE)
            builder.addAction(NotificationCompat.Action.Builder(0, context.getString(R.string.notification_popup_action_cancel), pendingIntent).build())
        }
    }

    private fun maybeAddUserActions(builder: NotificationCompat.Builder, notification: Notification) {
        notification.actions?.forEach { action ->
            val actionType = action.action.lowercase(Locale.getDefault())
            if (actionType == ACTION_VIEW) {
                // Hack: Action "view" with "clear=true" is a special case, because it's apparently impossible to start a
                // URL activity from PendingIntent.getActivity() and also close the notification. To clear it, we
                // launch our own Activity (ViewActionWithClearActivity) which then calls the actual activity

                if (action.clear == true) {
                    addViewUserActionWithClear(builder, notification, action)
                } else {
                    addViewUserActionWithoutClear(builder, action)
                }
            } else {
                addHttpOrBroadcastUserAction(builder, notification, action)
            }
        }
    }

    /**
     * Open the URL and do NOT cancel the notification (clear=false). This uses a normal Intent with the given URL.
     * The other case is much more interesting.
     */
    private fun addViewUserActionWithoutClear(builder: NotificationCompat.Builder, action: Action) {
        try {
            val url = action.url ?: return
            val intent = Intent(Intent.ACTION_VIEW, Uri.parse(url)).apply {
                addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK)
            }
            val pendingIntent = PendingIntent.getActivity(context, Random().nextInt(), intent, PendingIntent.FLAG_IMMUTABLE)
            builder.addAction(NotificationCompat.Action.Builder(0, action.label, pendingIntent).build())
        } catch (e: Exception) {
            Log.w(TAG, "Unable to add open user action", e)
        }
    }

    /**
     * HACK: Open the URL and CANCEL the notification (clear=true). This is a SPECIAL case with a horrible workaround.
     * We call our own activity ViewActionWithClearActivity and open the URL from there.
     */
    private fun addViewUserActionWithClear(builder: NotificationCompat.Builder, notification: Notification, action: Action) {
        try {
            val url = action.url ?: return
            val intent = Intent(context, ViewActionWithClearActivity::class.java).apply {
                addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK)
                putExtra(VIEW_ACTION_EXTRA_URL, url)
                putExtra(VIEW_ACTION_EXTRA_NOTIFICATION_ID, notification.notificationId)
            }
            val pendingIntent = PendingIntent.getActivity(context, Random().nextInt(), intent, PendingIntent.FLAG_IMMUTABLE)
            builder.addAction(NotificationCompat.Action.Builder(0, action.label, pendingIntent).build())
        } catch (e: Exception) {
            Log.w(TAG, "Unable to add open user action", e)
        }
    }

    private fun addHttpOrBroadcastUserAction(builder: NotificationCompat.Builder, notification: Notification, action: Action) {
        val intent = Intent(context, UserActionBroadcastReceiver::class.java).apply {
            putExtra(BROADCAST_EXTRA_TYPE, BROADCAST_TYPE_USER_ACTION)
            putExtra(BROADCAST_EXTRA_NOTIFICATION_ID, notification.id)
            putExtra(BROADCAST_EXTRA_ACTION_ID, action.id)
        }
        val pendingIntent = PendingIntent.getBroadcast(context, Random().nextInt(), intent, PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE)
        val label = formatActionLabel(action)
        builder.addAction(NotificationCompat.Action.Builder(0, label, pendingIntent).build())
    }

    /**
     * Receives the broadcast from
     * - the "http" and "broadcast" action button (the "view" action is handled differently)
     * - the "download"/"cancel" action button
     *
     * Then queues a Worker via WorkManager to execute the action in the background
     */
    class UserActionBroadcastReceiver : BroadcastReceiver() {
        override fun onReceive(context: Context, intent: Intent) {
            val type = intent.getStringExtra(BROADCAST_EXTRA_TYPE) ?: return
            val notificationId = intent.getStringExtra(BROADCAST_EXTRA_NOTIFICATION_ID) ?: return
            when (type) {
                BROADCAST_TYPE_DOWNLOAD_START -> DownloadManager.enqueue(context, notificationId, userAction = true, DownloadType.ATTACHMENT)
                BROADCAST_TYPE_DOWNLOAD_CANCEL -> DownloadManager.cancel(context, notificationId)
                BROADCAST_TYPE_USER_ACTION -> {
                    val actionId = intent.getStringExtra(BROADCAST_EXTRA_ACTION_ID) ?: return
                    UserActionManager.enqueue(context, notificationId, actionId)
                }
            }
        }
    }

    private fun detailActivityIntent(subscription: Subscription): PendingIntent? {
        val intent = Intent(context, DetailActivity::class.java).apply {
            putExtra(MainActivity.EXTRA_SUBSCRIPTION_ID, subscription.id)
            putExtra(MainActivity.EXTRA_SUBSCRIPTION_BASE_URL, subscription.baseUrl)
            putExtra(MainActivity.EXTRA_SUBSCRIPTION_TOPIC, subscription.topic)
            putExtra(MainActivity.EXTRA_SUBSCRIPTION_DISPLAY_NAME, displayName(subscription))
            putExtra(MainActivity.EXTRA_SUBSCRIPTION_INSTANT, subscription.instant)
            putExtra(MainActivity.EXTRA_SUBSCRIPTION_MUTED_UNTIL, subscription.mutedUntil)
        }
        return TaskStackBuilder.create(context).run {
            addNextIntentWithParentStack(intent) // Add the intent, which inflates the back stack
            getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE) // Get the PendingIntent containing the entire back stack
        }
    }

    private fun maybeCreateNotificationChannel(priority: Int) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            // Note: To change a notification channel, you must delete the old one and create a new one!

            val pause = 300L
            val channel = when (priority) {
                1 -> NotificationChannel(CHANNEL_ID_MIN, context.getString(R.string.channel_notifications_min_name), NotificationManager.IMPORTANCE_MIN)
                2 -> NotificationChannel(CHANNEL_ID_LOW, context.getString(R.string.channel_notifications_low_name), NotificationManager.IMPORTANCE_LOW)
                4 -> {
                    val channel = NotificationChannel(CHANNEL_ID_HIGH, context.getString(R.string.channel_notifications_high_name), NotificationManager.IMPORTANCE_HIGH)
                    channel.enableVibration(true)
                    channel.vibrationPattern = longArrayOf(
                        pause, 100, pause, 100, pause, 100,
                        pause, 2000
                    )
                    channel
                }
                5 -> {
                    val channel = NotificationChannel(CHANNEL_ID_MAX, context.getString(R.string.channel_notifications_max_name), NotificationManager.IMPORTANCE_HIGH) // IMPORTANCE_MAX does not exist
                    channel.enableLights(true)
                    channel.enableVibration(true)
                    channel.vibrationPattern = longArrayOf(
                        pause, 100, pause, 100, pause, 100,
                        pause, 2000,
                        pause, 100, pause, 100, pause, 100,
                        pause, 2000,
                        pause, 100, pause, 100, pause, 100,
                        pause, 2000
                    )
                    channel
                }
                else -> NotificationChannel(CHANNEL_ID_DEFAULT, context.getString(R.string.channel_notifications_default_name), NotificationManager.IMPORTANCE_DEFAULT)
            }
            notificationManager.createNotificationChannel(channel)
        }
    }

    private fun toChannelId(priority: Int): String {
        return when (priority) {
            1 -> CHANNEL_ID_MIN
            2 -> CHANNEL_ID_LOW
            4 -> CHANNEL_ID_HIGH
            5 -> CHANNEL_ID_MAX
            else -> CHANNEL_ID_DEFAULT
        }
    }

    /**
     * Activity used to launch a URL.
     * .
     * Horrible hack: Action "view" with "clear=true" is a special case, because it's apparently impossible to start a
     * URL activity from PendingIntent.getActivity() and also close the notification. To clear it, we
     * launch this activity which then calls the actual activity.
     */
    class ViewActionWithClearActivity : Activity() {
        override fun onCreate(savedInstanceState: Bundle?) {
            super.onCreate(savedInstanceState)
            Log.d(TAG, "Created $this")
            val url = intent.getStringExtra(VIEW_ACTION_EXTRA_URL)
            val notificationId = intent.getIntExtra(VIEW_ACTION_EXTRA_NOTIFICATION_ID, 0)
            if (url == null) {
                finish()
                return
            }

            // Immediately start the actual activity
            try {
                val intent = Intent(Intent.ACTION_VIEW, Uri.parse(url)).apply {
                    addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
                }
                startActivity(intent)
            } catch (e: Exception) {
                Log.w(TAG, "Unable to start activity from URL $url", e)
                val message = if (e is ActivityNotFoundException) url else e.message
                Toast
                    .makeText(this, getString(R.string.detail_item_cannot_open_url, message), Toast.LENGTH_LONG)
                    .show()
            }

            // Cancel notification
            val notifier = NotificationService(this)
            notifier.cancel(notificationId)

            // Close this activity
            finish()
        }
    }

    companion object {
        const val ACTION_VIEW = "view"
        const val ACTION_HTTP = "http"
        const val ACTION_BROADCAST = "broadcast"

        const val BROADCAST_EXTRA_TYPE = "type"
        const val BROADCAST_EXTRA_NOTIFICATION_ID = "notificationId"
        const val BROADCAST_EXTRA_ACTION_ID = "actionId"

        const val BROADCAST_TYPE_DOWNLOAD_START = "io.heckel.ntfy.DOWNLOAD_ACTION_START"
        const val BROADCAST_TYPE_DOWNLOAD_CANCEL = "io.heckel.ntfy.DOWNLOAD_ACTION_CANCEL"
        const val BROADCAST_TYPE_USER_ACTION = "io.heckel.ntfy.USER_ACTION_RUN"

        private const val TAG = "NtfyNotifService"

        private const val CHANNEL_ID_MIN = "ntfy-min"
        private const val CHANNEL_ID_LOW = "ntfy-low"
        private const val CHANNEL_ID_DEFAULT = "ntfy"
        private const val CHANNEL_ID_HIGH = "ntfy-high"
        private const val CHANNEL_ID_MAX = "ntfy-max"

        private const val VIEW_ACTION_EXTRA_URL = "url"
        private const val VIEW_ACTION_EXTRA_NOTIFICATION_ID = "notificationId"
    }
}