using System;
using System.Linq;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Android;

#if UNITY_2022_2_OR_NEWER
using JniMethodID = System.IntPtr;
using JniFieldID = System.IntPtr;
#else
using JniMethodID = System.String;
using JniFieldID = System.String;
#endif

namespace Unity.Notifications.Android
{
    /// <summary>
    /// Current status of a scheduled notification, can be queried using CheckScheduledNotificationStatus.
    /// </summary>
    public enum NotificationStatus
    {
        /// <summary>
        /// Status of a specified notification cannot be determined. This is only supported on Android Marshmallow (6.0) and above.
        /// </summary>
        Unavailable = -1,

        /// <summary>
        /// A notification with a specified id could not be found.
        /// </summary>
        Unknown = 0,

        /// <summary>
        /// A notification with a specified id is scheduled but not yet delivered.
        /// </summary>
        Scheduled = 1,

        /// <summary>
        /// A notification with a specified id was already delivered.
        /// </summary>
        Delivered = 2,
    }

    struct NotificationManagerJni
    {
        private AndroidJavaClass klass;
        private AndroidJavaObject self;

        public AndroidJavaObject KEY_FIRE_TIME;
        public AndroidJavaObject KEY_ID;
        public AndroidJavaObject KEY_INTENT_DATA;
        public AndroidJavaObject KEY_LARGE_ICON;
        public AndroidJavaObject KEY_REPEAT_INTERVAL;
        public AndroidJavaObject KEY_NOTIFICATION;
        public AndroidJavaObject KEY_SMALL_ICON;
        public AndroidJavaObject KEY_SHOW_IN_FOREGROUND;

        private JniMethodID getNotificationFromIntent;
        private JniMethodID setNotificationIcon;
        private JniMethodID setNotificationColor;
        private JniMethodID getNotificationColor;
        private JniMethodID setNotificationUsesChronometer;
        private JniMethodID setNotificationGroupAlertBehavior;
        private JniMethodID getNotificationGroupAlertBehavior;
        private JniMethodID getNotificationChannelId;
        private JniMethodID scheduleNotification;
        private JniMethodID createNotificationBuilder;


        public NotificationManagerJni(AndroidJavaClass clazz, AndroidJavaObject obj)
        {
            klass = clazz;
            self = obj;

            getNotificationFromIntent = default;
            setNotificationIcon = default;
            setNotificationColor = default;
            getNotificationColor = default;
            setNotificationUsesChronometer = default;
            setNotificationGroupAlertBehavior = default;
            getNotificationGroupAlertBehavior = default;
            getNotificationChannelId = default;
            scheduleNotification = default;
            createNotificationBuilder = default;

#if UNITY_ANDROID && !UNITY_EDITOR
            KEY_FIRE_TIME = clazz.GetStatic<AndroidJavaObject>("KEY_FIRE_TIME");
            KEY_ID = clazz.GetStatic<AndroidJavaObject>("KEY_ID");
            KEY_INTENT_DATA = clazz.GetStatic<AndroidJavaObject>("KEY_INTENT_DATA");
            KEY_LARGE_ICON = clazz.GetStatic<AndroidJavaObject>("KEY_LARGE_ICON");
            KEY_REPEAT_INTERVAL = clazz.GetStatic<AndroidJavaObject>("KEY_REPEAT_INTERVAL");
            KEY_NOTIFICATION = clazz.GetStatic<AndroidJavaObject>("KEY_NOTIFICATION");
            KEY_SMALL_ICON = clazz.GetStatic<AndroidJavaObject>("KEY_SMALL_ICON");
            KEY_SHOW_IN_FOREGROUND = clazz.GetStatic<AndroidJavaObject>("KEY_SHOW_IN_FOREGROUND");

            CollectMethods(clazz);
#else
            KEY_FIRE_TIME = null;
            KEY_ID = null;
            KEY_INTENT_DATA = null;
            KEY_LARGE_ICON = null;
            KEY_REPEAT_INTERVAL = null;
            KEY_NOTIFICATION = null;
            KEY_SMALL_ICON = null;
            KEY_SHOW_IN_FOREGROUND = null;
#endif
        }

        void CollectMethods(AndroidJavaClass clazz)
        {
            getNotificationFromIntent = JniApi.FindMethod(clazz, "getNotificationFromIntent", "(Landroid/content/Intent;)Landroid/app/Notification;", false);
            setNotificationIcon = JniApi.FindMethod(clazz, "setNotificationIcon", "(Landroid/app/Notification$Builder;Ljava/lang/String;Ljava/lang/String;)V", true);
            setNotificationColor = JniApi.FindMethod(clazz, "setNotificationColor", "(Landroid/app/Notification$Builder;I)V", true);
            getNotificationColor = JniApi.FindMethod(clazz, "getNotificationColor", "(Landroid/app/Notification;)Ljava/lang/Integer;", true);
            setNotificationUsesChronometer = JniApi.FindMethod(clazz, "setNotificationUsesChronometer", "(Landroid/app/Notification$Builder;Z)V", true);
            setNotificationGroupAlertBehavior = JniApi.FindMethod(clazz, "setNotificationGroupAlertBehavior", "(Landroid/app/Notification$Builder;I)V", true);
            getNotificationGroupAlertBehavior = JniApi.FindMethod(clazz, "getNotificationGroupAlertBehavior", "(Landroid/app/Notification;)I", true);
            getNotificationChannelId = JniApi.FindMethod(clazz, "getNotificationChannelId", "(Landroid/app/Notification;)Ljava/lang/String;", true);
            scheduleNotification = JniApi.FindMethod(clazz, "scheduleNotification", "(Landroid/app/Notification$Builder;Z)I", false);
            createNotificationBuilder = JniApi.FindMethod(clazz, "createNotificationBuilder", "(Ljava/lang/String;)Landroid/app/Notification$Builder;", false);
        }

        public AndroidJavaObject GetNotificationFromIntent(AndroidJavaObject intent)
        {
            return self.Call<AndroidJavaObject>(getNotificationFromIntent, intent);
        }

        public void SetNotificationIcon(AndroidJavaObject builder, AndroidJavaObject keyName, string icon)
        {
            klass.CallStatic(setNotificationIcon, builder, keyName, icon);
        }

        public void SetNotificationColor(AndroidJavaObject builder, int color)
        {
            klass.CallStatic(setNotificationColor, builder, color);
        }

        public Color? GetNotificationColor(AndroidJavaObject notification)
        {
            using (var color = klass.CallStatic<AndroidJavaObject>(getNotificationColor, notification))
            {
                if (color == null)
                    return null;
#if UNITY_2022_2_OR_NEWER
                int val;
                AndroidJNIHelper.Unbox(color.GetRawObject(), out val);
                return val.ToColor();
#else
                return color.Call<int>("intValue").ToColor();
#endif
            }
        }

        public void SetNotificationUsesChronometer(AndroidJavaObject builder, bool usesStopwatch)
        {
            klass.CallStatic(setNotificationUsesChronometer, builder, usesStopwatch);
        }

        public void SetNotificationGroupAlertBehavior(AndroidJavaObject builder, int groupAlertBehaviour)
        {
            klass.CallStatic(setNotificationGroupAlertBehavior, builder, groupAlertBehaviour);
        }

        public int GetNotificationGroupAlertBehavior(AndroidJavaObject notification)
        {
            return klass.CallStatic<int>(getNotificationGroupAlertBehavior, notification);
        }

        public string GetNotificationChannelId(AndroidJavaObject notification)
        {
            return klass.CallStatic<string>(getNotificationChannelId, notification);
        }

        public void RegisterNotificationChannel(AndroidNotificationChannel channel)
        {
            self.Call("registerNotificationChannel",
                channel.Id,
                channel.Name,
                (int)channel.Importance,
                channel.Description,
                channel.EnableLights,
                channel.EnableVibration,
                channel.CanBypassDnd,
                channel.CanShowBadge,
                channel.VibrationPattern,
                (int)channel.LockScreenVisibility
            );
        }

        public AndroidJavaObject[] GetNotificationChannels()
        {
            return self.Call<AndroidJavaObject[]>("getNotificationChannels");
        }

        public void DeleteNotificationChannel(string channelId)
        {
            self.Call("deleteNotificationChannel", channelId);
        }

        public int ScheduleNotification(AndroidJavaObject notificationBuilder, bool customized)
        {
            return self.Call<int>(scheduleNotification, notificationBuilder, customized);
        }

        public bool CheckIfPendingNotificationIsRegistered(int id)
        {
            return self.Call<bool>("checkIfPendingNotificationIsRegistered", id);
        }

        public void CancelPendingNotification(int id)
        {
            self.Call("cancelPendingNotification", id);
        }

        public void CancelDisplayedNotification(int id)
        {
            self.Call("cancelDisplayedNotification", id);
        }

        public void CancelAllPendingNotificationIntents()
        {
            self.Call("cancelAllPendingNotificationIntents");
        }

        public void CancelAllNotifications()
        {
            self.Call("cancelAllNotifications");
        }

        public int CheckNotificationStatus(int id)
        {
            return self.Call<int>("checkNotificationStatus", id);
        }

        public void ShowNotificationSettings(string channelId)
        {
            self.Call("showNotificationSettings", channelId);
        }

        public AndroidJavaObject CreateNotificationBuilder(String channelId)
        {
            return self.Call<AndroidJavaObject>(createNotificationBuilder, channelId);
        }
    }

    struct NotificationJni
    {
        public AndroidJavaObject EXTRA_TITLE;
        public AndroidJavaObject EXTRA_TEXT;
        public AndroidJavaObject EXTRA_SHOW_CHRONOMETER;
        public AndroidJavaObject EXTRA_BIG_TEXT;
        public AndroidJavaObject EXTRA_SHOW_WHEN;
        public int FLAG_AUTO_CANCEL;
        public int FLAG_GROUP_SUMMARY;

        JniMethodID getGroup;
        JniMethodID getSortKey;

        JniFieldID extras;
        JniFieldID flags;
        JniFieldID number;
        JniFieldID when;

        public void CollectJni()
        {
            using (var notificationClass = new AndroidJavaClass("android.app.Notification"))
            {
                CollectConstants(notificationClass);
                CollectMethods(notificationClass);
                CollectFields(notificationClass);
            }
        }

        void CollectConstants(AndroidJavaClass clazz)
        {
            EXTRA_TITLE = clazz.GetStatic<AndroidJavaObject>("EXTRA_TITLE");
            EXTRA_TEXT = clazz.GetStatic<AndroidJavaObject>("EXTRA_TEXT");
            EXTRA_SHOW_CHRONOMETER = clazz.GetStatic<AndroidJavaObject>("EXTRA_SHOW_CHRONOMETER");
            EXTRA_BIG_TEXT = clazz.GetStatic<AndroidJavaObject>("EXTRA_BIG_TEXT");
            EXTRA_SHOW_WHEN = clazz.GetStatic<AndroidJavaObject>("EXTRA_SHOW_WHEN");
            FLAG_AUTO_CANCEL = clazz.GetStatic<int>("FLAG_AUTO_CANCEL");
            FLAG_GROUP_SUMMARY = clazz.GetStatic<int>("FLAG_GROUP_SUMMARY");
        }

        void CollectMethods(AndroidJavaClass clazz)
        {
            getGroup = JniApi.FindMethod(clazz, "getGroup", "()Ljava/lang/String;", false);
            getSortKey = JniApi.FindMethod(clazz, "getSortKey", "()Ljava/lang/String;", false);
        }

        void CollectFields(AndroidJavaClass clazz)
        {
            extras = JniApi.FindField(clazz, "extras", "Landroid/os/Bundle;", false);
            flags = JniApi.FindField(clazz, "flags", "I", false);
            number = JniApi.FindField(clazz, "number", "I", false);
            when = JniApi.FindField(clazz, "when", "J", false);
        }

        public AndroidJavaObject Extras(AndroidJavaObject notification)
        {
            return notification.Get<AndroidJavaObject>(extras);
        }

        public int Flags(AndroidJavaObject notification)
        {
            return notification.Get<int>(flags);
        }

        public int Number(AndroidJavaObject notification)
        {
            return notification.Get<int>(number);
        }

        public string GetGroup(AndroidJavaObject notification)
        {
            return notification.Call<string>(getGroup);
        }

        public string GetSortKey(AndroidJavaObject notification)
        {
            return notification.Call<string>(getSortKey);
        }

        internal long When(AndroidJavaObject notification)
        {
            return notification.Get<long>(when);
        }
    }

    struct NotificationBuilderJni
    {
        JniMethodID getExtras;
        JniMethodID setContentTitle;
        JniMethodID setContentText;
        JniMethodID setAutoCancel;
        JniMethodID setNumber;
        JniMethodID setStyle;
        JniMethodID setWhen;
        JniMethodID setGroup;
        JniMethodID setGroupSummary;
        JniMethodID setSortKey;
        JniMethodID setShowWhen;

        public void CollectJni()
        {
            using (var clazz = new AndroidJavaClass("android.app.Notification$Builder"))
            {
                getExtras = JniApi.FindMethod(clazz, "getExtras", "()Landroid/os/Bundle;", false);
                setContentTitle = JniApi.FindMethod(clazz, "setContentTitle", "(Ljava/lang/CharSequence;)Landroid/app/Notification$Builder;", false);
                setContentText = JniApi.FindMethod(clazz, "setContentText", "(Ljava/lang/CharSequence;)Landroid/app/Notification$Builder;", false);
                setAutoCancel = JniApi.FindMethod(clazz, "setAutoCancel", "(Z)Landroid/app/Notification$Builder;", false);
                setNumber = JniApi.FindMethod(clazz, "setNumber", "(I)Landroid/app/Notification$Builder;", false);
                setStyle = JniApi.FindMethod(clazz, "setStyle", "(Landroid/app/Notification$Style;)Landroid/app/Notification$Builder;", false);
                setWhen = JniApi.FindMethod(clazz, "setWhen", "(J)Landroid/app/Notification$Builder;", false);
                setGroup = JniApi.FindMethod(clazz, "setGroup", "(Ljava/lang/String;)Landroid/app/Notification$Builder;", false);
                setGroupSummary = JniApi.FindMethod(clazz, "setGroupSummary", "(Z)Landroid/app/Notification$Builder;", false);
                setSortKey = JniApi.FindMethod(clazz, "setSortKey", "(Ljava/lang/String;)Landroid/app/Notification$Builder;", false);
                setShowWhen = JniApi.FindMethod(clazz, "setShowWhen", "(Z)Landroid/app/Notification$Builder;", false);
            }
        }

        public AndroidJavaObject GetExtras(AndroidJavaObject builder)
        {
            return builder.Call<AndroidJavaObject>(getExtras);
        }

        public void SetContentTitle(AndroidJavaObject builder, string title)
        {
            builder.Call<AndroidJavaObject>(setContentTitle, title).Dispose();
        }

        public void SetContentText(AndroidJavaObject builder, string text)
        {
            builder.Call<AndroidJavaObject>(setContentText, text).Dispose();
        }

        public void SetAutoCancel(AndroidJavaObject builder, bool shouldAutoCancel)
        {
            builder.Call<AndroidJavaObject>(setAutoCancel, shouldAutoCancel).Dispose();
        }

        public void SetNumber(AndroidJavaObject builder, int number)
        {
            builder.Call<AndroidJavaObject>(setNumber, number).Dispose();
        }

        public void SetStyle(AndroidJavaObject builder, AndroidJavaObject style)
        {
            builder.Call<AndroidJavaObject>(setStyle, style).Dispose();
        }

        public void SetWhen(AndroidJavaObject builder, long timestamp)
        {
            builder.Call<AndroidJavaObject>(setWhen, timestamp).Dispose();
        }

        public void SetGroup(AndroidJavaObject builder, string group)
        {
            builder.Call<AndroidJavaObject>(setGroup, group).Dispose();
        }

        public void SetGroupSummary(AndroidJavaObject builder, bool groupSummary)
        {
            builder.Call<AndroidJavaObject>(setGroupSummary, groupSummary).Dispose();
        }

        public void SetSortKey(AndroidJavaObject builder, string sortKey)
        {
            builder.Call<AndroidJavaObject>(setSortKey, sortKey).Dispose();
        }

        public void SetShowWhen(AndroidJavaObject builder, bool showTimestamp)
        {
            builder.Call<AndroidJavaObject>(setShowWhen, showTimestamp).Dispose();
        }
    }

    struct BundleJni
    {
        JniMethodID containsKey;
        JniMethodID getBoolean;
        JniMethodID getInt;
        JniMethodID getLong;
        JniMethodID getString;
        JniMethodID putBoolean;
        JniMethodID putInt;
        JniMethodID putLong;
        JniMethodID putString;

        public void CollectJni()
        {
            using (var clazz = new AndroidJavaClass("android/os/Bundle"))
            {
                containsKey = JniApi.FindMethod(clazz, "containsKey", "(Ljava/lang/String;)Z", false);
                getBoolean = JniApi.FindMethod(clazz, "getBoolean", "(Ljava/lang/String;Z)Z", false);
                getInt = JniApi.FindMethod(clazz, "getInt", "(Ljava/lang/String;I)I", false);
                getLong = JniApi.FindMethod(clazz, "getLong", "(Ljava/lang/String;J)J", false);
                getString = JniApi.FindMethod(clazz, "getString", "(Ljava/lang/String;)Ljava/lang/String;", false);
                putBoolean = JniApi.FindMethod(clazz, "putBoolean", "(Ljava/lang/String;Z)V", false);
                putInt = JniApi.FindMethod(clazz, "putInt", "(Ljava/lang/String;I)V", false);
                putLong = JniApi.FindMethod(clazz, "putLong", "(Ljava/lang/String;J)V", false);
                putString = JniApi.FindMethod(clazz, "putString", "(Ljava/lang/String;Ljava/lang/String;)V", false);
            }
        }

        public bool ContainsKey(AndroidJavaObject bundle, AndroidJavaObject key)
        {
            return bundle.Call<bool>(containsKey, key);
        }

        public bool GetBoolean(AndroidJavaObject bundle, AndroidJavaObject key, bool defaultValue)
        {
            return bundle.Call<bool>(getBoolean, key, defaultValue);
        }

        public int GetInt(AndroidJavaObject bundle, AndroidJavaObject key, int defaultValue)
        {
            return bundle.Call<int>(getInt, key, defaultValue);
        }

        public long GetLong(AndroidJavaObject bundle, AndroidJavaObject key, long defaultValue)
        {
            return bundle.Call<long>(getLong, key, defaultValue);
        }

        public string GetString(AndroidJavaObject bundle, AndroidJavaObject key)
        {
            return bundle.Call<string>(getString, key);
        }

        public void PutBoolean(AndroidJavaObject bundle, AndroidJavaObject key, bool value)
        {
            bundle.Call(putBoolean, key, value);
        }

        public void PutInt(AndroidJavaObject bundle, AndroidJavaObject key, int value)
        {
            bundle.Call(putInt, key, value);
        }

        public void PutLong(AndroidJavaObject bundle, AndroidJavaObject key, long value)
        {
            bundle.Call(putLong, key, value);
        }

        public void PutString(AndroidJavaObject bundle, AndroidJavaObject key, string value)
        {
            bundle.Call(putString, key, value);
        }
    }

    struct JniApi
    {
        public NotificationManagerJni NotificationManager;
        public NotificationJni Notification;
        public NotificationBuilderJni NotificationBuilder;
        public BundleJni Bundle;

        public JniApi(AndroidJavaClass notificationManagerClass, AndroidJavaObject notificationManager)
        {
            NotificationManager = new NotificationManagerJni(notificationManagerClass, notificationManager);
            Notification = default;
            Notification.CollectJni();
            NotificationBuilder = default;
            NotificationBuilder.CollectJni();
            Bundle = default;
            Bundle.CollectJni();
        }

        public static JniFieldID FindField(AndroidJavaClass clazz, string name, string signature, bool isStatic)
        {
#if UNITY_2022_2_OR_NEWER
            var field = AndroidJNIHelper.GetFieldID(clazz.GetRawClass(), name, signature, isStatic);
            if (field == IntPtr.Zero)
                throw new Exception($"Field {name} with signature {signature} not found");
            return field;
#else
            return name;
#endif
        }

        public static JniMethodID FindMethod(AndroidJavaClass clazz, string name, string signature, bool isStatic)
        {
#if UNITY_2022_2_OR_NEWER
            var method = AndroidJNIHelper.GetMethodID(clazz.GetRawClass(), name, signature, isStatic);
            if (method == IntPtr.Zero)
                throw new Exception($"Method {name} with signature {signature} not found");
            return method;
#else
            return name;
#endif
        }
    }

    /// <summary>
    /// Use the AndroidNotificationCenter to register notification channels and schedule local notifications.
    /// </summary>
    public class AndroidNotificationCenter
    {
        private static int API_POST_NOTIFICATIONS_PERMISSION_REQUIRED = 33;
        internal static string PERMISSION_POST_NOTIFICATIONS = "android.permission.POST_NOTIFICATIONS";

        /// <summary>
        /// A PlayerPrefs key used to save users reply to POST_NOTIFICATIONS request (integer value of the PermissionStatus).
        /// </summary>
        /// <see cref="PermissionStatus"/>
        public static string SETTING_POST_NOTIFICATIONS_PERMISSION = "com.unity.androidnotifications.PostNotificationsPermission";

        /// <summary>
        /// The delegate type for the notification received callbacks.
        /// </summary>
        public delegate void NotificationReceivedCallback(AndroidNotificationIntentData data);

        /// <summary>
        /// Subscribe to this event to receive callbacks whenever a scheduled notification is shown to the user.
        /// </summary>
        public static event NotificationReceivedCallback OnNotificationReceived = delegate { };

        private static AndroidJavaObject s_CurrentActivity;
        private static JniApi s_Jni;
        private static int s_DeviceApiLevel;
        private static int s_TargetApiLevel;
        private static bool s_Initialized = false;

        /// <summary>
        /// Initialize the AndroidNotificationCenter class.
        /// Can be safely called multiple times
        /// </summary>
        /// <returns>True if has been successfully initialized</returns>
        public static bool Initialize()
        {
            if (s_Initialized)
                return true;

            if (AndroidReceivedNotificationMainThreadDispatcher.GetInstance() == null)
            {
                var receivedNotificationDispatcher = new GameObject("AndroidReceivedNotificationMainThreadDispatcher");
                receivedNotificationDispatcher.AddComponent<AndroidReceivedNotificationMainThreadDispatcher>();
            }

#if UNITY_EDITOR || !UNITY_ANDROID
            s_CurrentActivity = null;
#elif UNITY_ANDROID
            using (var unityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer"))
                s_CurrentActivity = unityPlayer.GetStatic<AndroidJavaObject>("currentActivity");

            var notificationManagerClass = new AndroidJavaClass("com.unity.androidnotifications.UnityNotificationManager");
            var notificationManager = notificationManagerClass.CallStatic<AndroidJavaObject>("getNotificationManagerImpl", s_CurrentActivity, new NotificationCallback());
            s_Jni = new JniApi(notificationManagerClass, notificationManager);

            using (var version = new AndroidJavaClass("android/os/Build$VERSION"))
                s_DeviceApiLevel = version.GetStatic<int>("SDK_INT");
            s_TargetApiLevel = notificationManager.Call<int>("getTargetSdk");

            s_Initialized = true;
#endif
            return s_Initialized;
        }

        internal static void SetPostPermissionSetting(PermissionStatus status)
        {
            PlayerPrefs.SetInt(SETTING_POST_NOTIFICATIONS_PERMISSION, (int)status);
        }

        /// <summary>
        /// Has user given permission to post notifications.
        /// Before Android 13 (API 33) no permission is required.
        /// </summary>
        public static PermissionStatus UserPermissionToPost
        {
            get
            {
                if (!Initialize())
                    return PermissionStatus.Denied;
                if (s_DeviceApiLevel < API_POST_NOTIFICATIONS_PERMISSION_REQUIRED)
                    return PermissionStatus.Allowed;

                var permissionStatus = (PermissionStatus)PlayerPrefs.GetInt(SETTING_POST_NOTIFICATIONS_PERMISSION, (int)PermissionStatus.NotRequested);
                var allowed = Permission.HasUserAuthorizedPermission(PERMISSION_POST_NOTIFICATIONS);
                if (allowed)
                {
                    if (permissionStatus != PermissionStatus.Allowed)
                        SetPostPermissionSetting(PermissionStatus.Allowed);
                    return PermissionStatus.Allowed;
                }

                switch (permissionStatus)
                {
                    case PermissionStatus.NotRequested:
                        break;
                    case PermissionStatus.Allowed:
                        permissionStatus = PermissionStatus.Denied;
                        SetPostPermissionSetting(permissionStatus);
                        break;
                    case PermissionStatus.DeniedDontAskAgain:  // no longer used, revert to Denied
                        permissionStatus = PermissionStatus.Denied;
                        break;
                }

                return permissionStatus;
            }
        }

        /// <summary>
        ///  Creates a notification channel that notifications can be posted to.
        ///  Notification channel settings can be changed by users on devices running Android 8.0 and above.
        ///  On older Android versions settings set on the notification channel struct will still be applied to the notification
        ///  if they are supported to by the Android version the app is running on.
        /// </summary>
        /// <param name="channel">Channel parameters</param>
        /// <remarks>
        ///  When a channel is deleted and recreated, all of the previous settings are restored. In order to change any settings
        ///  besides the name or description an entirely new channel (with a different channel ID) must be created.
        /// </remarks>
        public static void RegisterNotificationChannel(AndroidNotificationChannel channel)
        {
            if (!Initialize())
                return;

            if (string.IsNullOrEmpty(channel.Id))
            {
                throw new Exception("Cannot register notification channel, the channel ID is not specified.");
            }
            if (string.IsNullOrEmpty(channel.Name))
            {
                throw new Exception(string.Format("Cannot register notification channel: {0} , the channel Name is not set.", channel.Id));
            }
            if (string.IsNullOrEmpty(channel.Description))
            {
                throw new Exception(string.Format("Cannot register notification channel: {0} , the channel Description is not set.", channel.Id));
            }

            s_Jni.NotificationManager.RegisterNotificationChannel(channel);
        }

        /// <summary>
        /// Returns the notification channel with the specified id.
        /// The notification channel struct fields might not be identical to the channel struct used to initially register the channel if they were changed by the user.
        /// </summary>
        /// <param name="channelId">ID of the channel to retrieve</param>
        /// <returns>Channel with given ID or empty struct if such channel does not exist</returns>
        public static AndroidNotificationChannel GetNotificationChannel(string channelId)
        {
            return GetNotificationChannels().SingleOrDefault(channel => channel.Id == channelId);
        }

        /// <summary>
        /// Returns all notification channels that were created by the app.
        /// </summary>
        /// <returns>All existing channels</returns>
        public static AndroidNotificationChannel[] GetNotificationChannels()
        {
            if (!Initialize())
                return new AndroidNotificationChannel[0];

            var androidChannels = s_Jni.NotificationManager.GetNotificationChannels();
            var channels = new AndroidNotificationChannel[androidChannels == null ? 0 : androidChannels.Length];

            for (int i = 0; i < channels.Length; ++i)
            {
                var channel = androidChannels[i];
                var ch = new AndroidNotificationChannel();
                ch.Id = channel.Get<string>("id");
                ch.Name = channel.Get<string>("name");
                ch.Importance = channel.Get<int>("importance").ToImportance();
                ch.Description = channel.Get<string>("description");
                ch.EnableLights = channel.Get<bool>("enableLights");
                ch.EnableVibration = channel.Get<bool>("enableVibration");
                ch.CanBypassDnd = channel.Get<bool>("canBypassDnd");
                ch.CanShowBadge = channel.Get<bool>("canShowBadge");
                ch.VibrationPattern = channel.Get<long[]>("vibrationPattern");
                ch.LockScreenVisibility = channel.Get<int>("lockscreenVisibility").ToLockScreenVisibility();

                channels[i] = ch;
            }

            return channels;
        }

        /// <summary>
        /// Delete the specified notification channel.
        /// </summary>
        /// <param name="channelId">ID of the channel to delete</param>
        public static void DeleteNotificationChannel(string channelId)
        {
            if (Initialize())
                s_Jni.NotificationManager.DeleteNotificationChannel(channelId);
        }

        /// <summary>
        /// Schedule a notification which will be shown at the time specified in the notification struct.
        /// The returned id can later be used to update the notification before it's triggered, it's current status can be tracked using CheckScheduledNotificationStatus.
        /// </summary>
        /// <param name="notification">Data for the notification</param>
        /// <param name="channelId">ID of the channel to send notification to</param>
        /// <returns>The generated ID for the notification</returns>
        public static int SendNotification(AndroidNotification notification, string channelId)
        {
            if (!Initialize())
                return -1;

            using (var builder = CreateNotificationBuilder(notification, channelId))
                return ScheduleNotification(builder, false);
        }

        /// <summary>
        /// Schedule a notification which will be shown at the time specified in the notification struct.
        /// The specified id can later be used to update the notification before it's triggered, it's current status can be tracked using CheckScheduledNotificationStatus.
        /// </summary>
        /// <param name="notification">Data for the notification</param>
        /// <param name="channelId">ID of the channel to send notification to</param>
        /// <param name="id">A unique ID for the notification</param>
        public static void SendNotificationWithExplicitID(AndroidNotification notification, string channelId, int id)
        {
            if (Initialize())
                using (var builder = CreateNotificationBuilder(id, notification, channelId))
                    ScheduleNotification(builder, false);
        }

        /// <summary>
        /// Schedule a notification created using the provided Notification.Builder object.
        /// Notification builder should be created by calling CreateNotificationBuilder.
        /// </summary>
        public static void SendNotification(AndroidJavaObject notificationBuilder)
        {
            if (Initialize())
                ScheduleNotification(notificationBuilder, true);
        }

        /// <summary>
        /// Schedule a notification created using the provided Notification.Builder object.
        /// Notification builder should be created by calling CreateNotificationBuilder.
        /// Stores the notification id to the second argument
        /// </summary>
        public static void SendNotification(AndroidJavaObject notificationBuilder, out int id)
        {
            id = -1;
            if (Initialize())
                id = ScheduleNotification(notificationBuilder, true);
        }

        static int ScheduleNotification(AndroidJavaObject notificationBuilder, bool customized)
        {
            return s_Jni.NotificationManager.ScheduleNotification(notificationBuilder, customized);
        }

        /// <summary>
        /// Update an already scheduled notification.
        /// If a notification with the specified id was already scheduled it will be overridden with the information from the passed notification struct.
        /// </summary>
        /// <param name="id">ID of the notification to update</param>
        /// <param name="notification">Data for the notification</param>
        /// <param name="channelId">ID of the channel to send notification to</param>
        public static void UpdateScheduledNotification(int id, AndroidNotification notification, string channelId)
        {
            if (!Initialize())
                return;

            if (s_Jni.NotificationManager.CheckIfPendingNotificationIsRegistered(id))
            {
                using (var builder = CreateNotificationBuilder(id, notification, channelId))
                {
                    SendNotification(builder);
                }
            }
        }

        /// <summary>
        /// Cancel a scheduled or previously shown notification.
        /// The notification will no longer be displayed on it's scheduled time. If it's already delivered it will be removed from the status bar.
        /// </summary>
        /// <param name="id">ID of the notification to cancel</param>
        public static void CancelNotification(int id)
        {
            if (!Initialize())
                return;

            CancelScheduledNotification(id);
            CancelDisplayedNotification(id);
        }

        /// <summary>
        /// Cancel a scheduled notification.
        /// The notification will no longer be displayed on it's scheduled time. It it will not be removed from the status bar if it's already delivered.
        /// </summary>
        /// <param name="id">ID of the notification to cancel</param>
        public static void CancelScheduledNotification(int id)
        {
            if (Initialize())
                s_Jni.NotificationManager.CancelPendingNotification(id);
        }

        /// <summary>
        /// Cancel a previously shown notification.
        /// The notification will be removed from the status bar.
        /// </summary>
        /// <param name="id">ID of the notification to cancel</param>
        public static void CancelDisplayedNotification(int id)
        {
            if (Initialize())
                s_Jni.NotificationManager.CancelDisplayedNotification(id);
        }

        /// <summary>
        /// Cancel all notifications scheduled or previously shown by the app.
        /// All scheduled notifications will be canceled. All notifications shown by the app will be removed from the status bar.
        /// </summary>
        public static void CancelAllNotifications()
        {
            if (!Initialize())
                return;

            CancelAllScheduledNotifications();
            CancelAllDisplayedNotifications();
        }

        /// <summary>
        /// Cancel all notifications scheduled by the app.
        /// All scheduled notifications will be canceled. Notifications will not be removed from the status bar if they are already shown.
        /// </summary>
        public static void CancelAllScheduledNotifications()
        {
            if (Initialize())
                s_Jni.NotificationManager.CancelAllPendingNotificationIntents();
        }

        /// <summary>
        /// Cancel all previously shown notifications.
        /// All notifications shown by the app will be removed from the status bar. All scheduled notifications will still be shown on their scheduled time.
        /// </summary>
        public static void CancelAllDisplayedNotifications()
        {
            if (Initialize())
                s_Jni.NotificationManager.CancelAllNotifications();
        }

        /// <summary>
        /// Return the status of a scheduled notification.
        /// </summary>
        /// <param name="id">ID of the notification to check</param>
        /// <returns>The status of the notification</returns>
        public static NotificationStatus CheckScheduledNotificationStatus(int id)
        {
            if (!Initialize())
                return NotificationStatus.Unavailable;

            var status = s_Jni.NotificationManager.CheckNotificationStatus(id);
            return (NotificationStatus)status;
        }

        /// <summary>
        /// Allows retrieving the notification used to open the app. You can save arbitrary string data in the 'AndroidNotification.IntentData' field.
        /// </summary>
        /// <returns>
        /// Returns the AndroidNotification used to open the app, returns null if the app was not opened with a notification.
        /// </returns>
        public static AndroidNotificationIntentData GetLastNotificationIntent()
        {
            if (!Initialize())
                return null;

            var intent = s_CurrentActivity.Call<AndroidJavaObject>("getIntent");
            var notification = s_Jni.NotificationManager.GetNotificationFromIntent(intent);
            if (notification == null)
                return null;
            return GetNotificationData(notification);
        }

        /// <summary>
        /// Opens settings.
        /// On Android versions lower than 8.0 opens settings for the application.
        /// On Android 8.0 and later opens notification settings for the specified channel, or for the application, if channelId is null.
        /// Note, that opening settings will suspend the application and switch to settings app.
        /// </summary>
        /// <param name="channelId">ID for the channel to open or null to open notification settings for the application.</param>
        public static void OpenNotificationSettings(string channelId = null)
        {
            if (!Initialize())
                return;

            s_Jni.NotificationManager.ShowNotificationSettings(channelId);
        }

        /// <summary>
        /// Create Notification.Builder.
        /// Will automatically generate the ID for notification.
        /// <see cref="CreateNotificationBuilder(int, AndroidNotification, string)"/>
        /// </summary>
        public static AndroidJavaObject CreateNotificationBuilder(AndroidNotification notification, string channelId)
        {
            AndroidJavaObject builder, extras;
            CreateNotificationBuilder(notification, channelId, out builder, out extras);
            if (extras != null)
                extras.Dispose();
            return builder;
        }

        /// <summary>
        /// Create Notification.Builder object on Java side using privided AndroidNotification.
        /// </summary>
        /// <param name="id">ID for the notification</param>
        /// <param name="notification">Struct with notification data</param>
        /// <param name="channelId">Channel id</param>
        /// <returns>A proxy object for created Notification.Builder</returns>
        public static AndroidJavaObject CreateNotificationBuilder(int id, AndroidNotification notification, string channelId)
        {
            AndroidJavaObject builder, extras;
            CreateNotificationBuilder(notification, channelId, out builder, out extras);
            if (extras != null)
            {
                s_Jni.Bundle.PutInt(extras, s_Jni.NotificationManager.KEY_ID, id);
                extras.Dispose();
            }
            return builder;
        }

        static void CreateNotificationBuilder(AndroidNotification notification, string channelId, out AndroidJavaObject notificationBuilder, out AndroidJavaObject extras)
        {
            if (!Initialize())
            {
                notificationBuilder = extras = null;
                return;
            }

            long fireTime = notification.FireTime.ToLong();
            if (fireTime < 0L)
            {
                Debug.LogError("Failed to schedule notification, it did not contain a valid FireTime");
            }

            // NOTE: JNI calls are expensive, so we avoid calls that set something that is also a default

            notificationBuilder = s_Jni.NotificationManager.CreateNotificationBuilder(channelId);
            s_Jni.NotificationManager.SetNotificationIcon(notificationBuilder, s_Jni.NotificationManager.KEY_SMALL_ICON, notification.SmallIcon);
            if (!string.IsNullOrEmpty(notification.LargeIcon))
                s_Jni.NotificationManager.SetNotificationIcon(notificationBuilder, s_Jni.NotificationManager.KEY_LARGE_ICON, notification.LargeIcon);
            if (!string.IsNullOrEmpty(notification.Title))
                s_Jni.NotificationBuilder.SetContentTitle(notificationBuilder, notification.Title);
            if (!string.IsNullOrEmpty(notification.Text))
                s_Jni.NotificationBuilder.SetContentText(notificationBuilder, notification.Text);
            if (notification.ShouldAutoCancel)
                s_Jni.NotificationBuilder.SetAutoCancel(notificationBuilder, notification.ShouldAutoCancel);
            if (notification.Number >= 0)
                s_Jni.NotificationBuilder.SetNumber(notificationBuilder, notification.Number);
            if (notification.Style == NotificationStyle.BigTextStyle)
            {
                using (var style = new AndroidJavaObject("android.app.Notification$BigTextStyle"))
                {
                    style.Call<AndroidJavaObject>("bigText", notification.Text).Dispose();
                    s_Jni.NotificationBuilder.SetStyle(notificationBuilder, style);
                }
            }
            long timestampValue = notification.ShowCustomTimestamp ? notification.CustomTimestamp.ToLong() : fireTime;
            s_Jni.NotificationBuilder.SetWhen(notificationBuilder, timestampValue);
            if (!string.IsNullOrEmpty(notification.Group))
                s_Jni.NotificationBuilder.SetGroup(notificationBuilder, notification.Group);
            if (notification.GroupSummary)
                s_Jni.NotificationBuilder.SetGroupSummary(notificationBuilder, notification.GroupSummary);
            if (!string.IsNullOrEmpty(notification.SortKey))
                s_Jni.NotificationBuilder.SetSortKey(notificationBuilder, notification.SortKey);
            if (notification.ShowTimestamp)
                s_Jni.NotificationBuilder.SetShowWhen(notificationBuilder, notification.ShowTimestamp);
            int color = notification.Color.ToInt();
            if (color != 0)
                s_Jni.NotificationManager.SetNotificationColor(notificationBuilder, color);
            if (notification.UsesStopwatch)
                s_Jni.NotificationManager.SetNotificationUsesChronometer(notificationBuilder, notification.UsesStopwatch);
            if (notification.GroupAlertBehaviour != GroupAlertBehaviours.GroupAlertAll)  // All is default value
                s_Jni.NotificationManager.SetNotificationGroupAlertBehavior(notificationBuilder, (int)notification.GroupAlertBehaviour);

            extras = s_Jni.NotificationBuilder.GetExtras(notificationBuilder);
            s_Jni.Bundle.PutLong(extras, s_Jni.NotificationManager.KEY_REPEAT_INTERVAL, notification.RepeatInterval.ToLong());
            s_Jni.Bundle.PutLong(extras, s_Jni.NotificationManager.KEY_FIRE_TIME, fireTime);
            s_Jni.Bundle.PutBoolean(extras, s_Jni.NotificationManager.KEY_SHOW_IN_FOREGROUND, notification.ShowInForeground);
            if (!string.IsNullOrEmpty(notification.IntentData))
                s_Jni.Bundle.PutString(extras, s_Jni.NotificationManager.KEY_INTENT_DATA, notification.IntentData);
        }

        internal static AndroidNotificationIntentData GetNotificationData(AndroidJavaObject notificationObj)
        {
            using (var extras = s_Jni.Notification.Extras(notificationObj))
            {
                var id = s_Jni.Bundle.GetInt(extras, s_Jni.NotificationManager.KEY_ID, -1);
                if (id == -1)
                    return null;

                var channelId = s_Jni.NotificationManager.GetNotificationChannelId(notificationObj);
                int flags = s_Jni.Notification.Flags(notificationObj);

                var notification = new AndroidNotification();
                notification.Title = s_Jni.Bundle.GetString(extras, s_Jni.Notification.EXTRA_TITLE);
                notification.Text = s_Jni.Bundle.GetString(extras, s_Jni.Notification.EXTRA_TEXT);
                notification.SmallIcon = s_Jni.Bundle.GetString(extras, s_Jni.NotificationManager.KEY_SMALL_ICON);
                notification.LargeIcon = s_Jni.Bundle.GetString(extras, s_Jni.NotificationManager.KEY_LARGE_ICON);
                notification.ShouldAutoCancel = 0 != (flags & s_Jni.Notification.FLAG_AUTO_CANCEL);
                notification.UsesStopwatch = s_Jni.Bundle.GetBoolean(extras, s_Jni.Notification.EXTRA_SHOW_CHRONOMETER, false);
                notification.FireTime = s_Jni.Bundle.GetLong(extras, s_Jni.NotificationManager.KEY_FIRE_TIME, -1L).ToDatetime();
                notification.RepeatInterval = s_Jni.Bundle.GetLong(extras, s_Jni.NotificationManager.KEY_REPEAT_INTERVAL, -1L).ToTimeSpan();
                notification.ShowInForeground = s_Jni.Bundle.GetBoolean(extras, s_Jni.NotificationManager.KEY_SHOW_IN_FOREGROUND, true);

                if (s_Jni.Bundle.ContainsKey(extras, s_Jni.Notification.EXTRA_BIG_TEXT))
                    notification.Style = NotificationStyle.BigTextStyle;
                else
                    notification.Style = NotificationStyle.None;

                notification.Color = s_Jni.NotificationManager.GetNotificationColor(notificationObj);
                notification.Number = s_Jni.Notification.Number(notificationObj);
                notification.IntentData = s_Jni.Bundle.GetString(extras, s_Jni.NotificationManager.KEY_INTENT_DATA);
                notification.Group = s_Jni.Notification.GetGroup(notificationObj);
                notification.GroupSummary = 0 != (flags & s_Jni.Notification.FLAG_GROUP_SUMMARY);
                notification.SortKey = s_Jni.Notification.GetSortKey(notificationObj);
                notification.GroupAlertBehaviour = s_Jni.NotificationManager.GetNotificationGroupAlertBehavior(notificationObj).ToGroupAlertBehaviours();
                var showTimestamp = s_Jni.Bundle.GetBoolean(extras, s_Jni.Notification.EXTRA_SHOW_WHEN, false);
                notification.ShowTimestamp = showTimestamp;
                if (showTimestamp)
                    notification.CustomTimestamp = s_Jni.Notification.When(notificationObj).ToDatetime();

                var data = new AndroidNotificationIntentData(id, channelId, notification);
                data.NativeNotification = notificationObj;
                return data;
            }
        }

        internal static void ReceivedNotificationCallback(AndroidJavaObject notification)
        {
            var data = GetNotificationData(notification);
            OnNotificationReceived(data);
        }
    }
}