using System;
using System.Collections.Generic;
using UnityEngine;
using static UnityEditor.Toast;

namespace UnityEditor
{
    internal static class ToastManager
    {
        private const float NOTIFICATION_MARGIN = 5f;
        private const double TARGET_FRAME_TIME = 1.0 / 30.0;

        private static readonly List<Toast> topLeftNotifications = new();
        private static readonly List<Toast> topRightNotifications = new();
        private static readonly List<Toast> topCenterNotifications = new();
        private static readonly List<Toast> bottomLeftNotifications = new();
        private static readonly List<Toast> bottomRightNotifications = new();
        private static readonly List<Toast> bottomCenterNotifications = new();

        private static int notificationCount = 0;

        [InitializeOnLoadMethod]
        private static void Init()
        {
            AssemblyReloadEvents.beforeAssemblyReload += OnBeforeDomainReload;

            EnsureUpdateHook();

            EditorApplication.QueuePlayerLoopUpdate();
        }

        private static void EnsureUpdateHook()
        {
            EditorApplication.update -= CustomUpdateLoop;
            EditorApplication.update += CustomUpdateLoop;
        }

        private static void OnBeforeDomainReload()
        {
            //close all notifications on domain reload
            EditorApplication.update -= CustomUpdateLoop;

            for (var index = topLeftNotifications.Count - 1; index >= 0; index--)
            {
                var notification = topLeftNotifications[index];
                RemoveNotification(notification);
                notification.Close();
            }

            for (var index = topRightNotifications.Count - 1; index >= 0; index--)
            {
                var notification = topRightNotifications[index];
                RemoveNotification(notification);
                notification.Close();
            }

            for (var index = topCenterNotifications.Count - 1; index >= 0; index--)
            {
                var notification = topCenterNotifications[index];
                RemoveNotification(notification);
                notification.Close();
            }

            for (var index = bottomLeftNotifications.Count - 1; index >= 0; index--)
            {
                var notification = bottomLeftNotifications[index];
                RemoveNotification(notification);
                notification.Close();
            }

            for (var index = bottomRightNotifications.Count - 1; index >= 0; index--)
            {
                var notification = bottomRightNotifications[index];
                RemoveNotification(notification);
                notification.Close();
            }

            for (var index = bottomCenterNotifications.Count - 1; index >= 0; index--)
            {
                var notification = bottomCenterNotifications[index];
                RemoveNotification(notification);
                notification.Close();
            }
        }

        private static void CustomUpdateLoop()
        {
            if (notificationCount <= 0) return;

            UpdateNotifications(TARGET_FRAME_TIME);

            if (!EditorApplication.isPlaying || notificationCount > 0)
            {
                EditorApplication.delayCall += () =>
                {
                    EditorWindow.focusedWindow?.Repaint();
                    SceneView.RepaintAll();
                };
            }
        }

        private static void UpdateNotifications(double deltaTime)
        {
            CheckNotificationLifetimes();

            UpdateNotificationPositions(deltaTime);
        }

        private static void CheckNotificationLifetimes()
        {
            for (var index = topLeftNotifications.Count - 1; index >= 0; index--)
            {
                var notification = topLeftNotifications[index];
                if (!notification.IsLifetimeOver()) continue;
                RemoveNotification(notification);
                notification.Close();
            }

            for (var index = topRightNotifications.Count - 1; index >= 0; index--)
            {
                var notification = topRightNotifications[index];
                if (!notification.IsLifetimeOver()) continue;
                RemoveNotification(notification);
                notification.Close();
            }

            for (var index = topCenterNotifications.Count - 1; index >= 0; index--)
            {
                var notification = topCenterNotifications[index];
                if (!notification.IsLifetimeOver()) continue;
                RemoveNotification(notification);
                notification.Close();
            }

            for (var index = bottomLeftNotifications.Count - 1; index >= 0; index--)
            {
                var notification = bottomLeftNotifications[index];
                if (!notification.IsLifetimeOver()) continue;
                RemoveNotification(notification);
                notification.Close();
            }

            for (var index = bottomRightNotifications.Count - 1; index >= 0; index--)
            {
                var notification = bottomRightNotifications[index];
                if (!notification.IsLifetimeOver()) continue;
                RemoveNotification(notification);
                notification.Close();
            }

            for (var index = bottomCenterNotifications.Count - 1; index >= 0; index--)
            {
                var notification = bottomCenterNotifications[index];
                if (!notification.IsLifetimeOver()) continue;
                RemoveNotification(notification);
                notification.Close();
            }
        }

        private static void UpdateNotificationPositions(double deltaTime)
        {
            UpdateNotificationPositions(ToastPosition.TopLeft, deltaTime);
            UpdateNotificationPositions(ToastPosition.TopRight, deltaTime);
            UpdateNotificationPositions(ToastPosition.TopCenter, deltaTime);
            UpdateNotificationPositions(ToastPosition.BottomLeft, deltaTime);
            UpdateNotificationPositions(ToastPosition.BottomRight, deltaTime);
            UpdateNotificationPositions(ToastPosition.BottomCenter, deltaTime);
        }

        public static void ShowNotification(ToastArgs toastArgs, Vector2 windowSize = default)
        {
            EnsureUpdateHook();

            //Create the window
            var notification = ScriptableObject.CreateInstance<Toast>();

            notification.titleContent = new GUIContent($"Notification - {toastArgs.Title}");
            notification.minSize = windowSize == default ? new Vector2(250, 100) : windowSize;
            notification.maxSize = notification.minSize;
            notification.position = new Rect(0, 0, notification.minSize.x, notification.minSize.y);
            notification.ShowPopup();

            notification.OnClose += RemoveNotification;

            //Set position
            notification.SetupWindow(new ToastData
            {
                ToastArgs = toastArgs,
                TimeCreated = Time.time,
            });

            //Update other notifications
            AddNotification(notification);

        }

        private static void AddNotification(Toast toast)
        {
            switch (toast.Args.ToastPosition)
            {
                case ToastPosition.TopLeft:
                    topLeftNotifications.Insert(0, toast);
                    break;
                case ToastPosition.TopRight:
                    topRightNotifications.Insert(0, toast);
                    break;
                case ToastPosition.TopCenter:
                    topCenterNotifications.Insert(0, toast);
                    break;
                case ToastPosition.BottomLeft:
                    bottomLeftNotifications.Insert(0, toast);
                    break;
                case ToastPosition.BottomRight:
                    bottomRightNotifications.Insert(0, toast);
                    break;
                case ToastPosition.BottomCenter:
                    bottomCenterNotifications.Insert(0, toast);
                    break;
                default:
                    throw new ArgumentOutOfRangeException(null);
            }

            notificationCount++;
        }

        private static void RemoveNotification(Toast toast)
        {
            toast.OnClose -= RemoveNotification;
            switch (toast.Args.ToastPosition)
            {
                case ToastPosition.TopLeft:
                    topLeftNotifications.Remove(toast);
                    break;
                case ToastPosition.TopRight:
                    topRightNotifications.Remove(toast);
                    break;
                case ToastPosition.TopCenter:
                    topCenterNotifications.Remove(toast);
                    break;
                case ToastPosition.BottomLeft:
                    bottomLeftNotifications.Remove(toast);
                    break;
                case ToastPosition.BottomRight:
                    bottomRightNotifications.Remove(toast);
                    break;
                case ToastPosition.BottomCenter:
                    bottomCenterNotifications.Remove(toast);
                    break;
                default:
                    throw new ArgumentOutOfRangeException(null);
            }

            notificationCount--;
        }

        private static void UpdateNotificationPositions(ToastPosition toastPosition, double deltaTime)
        {
            var currentHeightOffset = 0f;
            switch (toastPosition)
            {
                case ToastPosition.TopLeft:
                    foreach (var currentNotification in topLeftNotifications)
                    {
                        var positionRect = currentNotification.GetEditorWindowPosition(toastPosition);
                        currentNotification.UpdatePosition(positionRect, currentHeightOffset, deltaTime);
                        currentHeightOffset += currentNotification.GetHeight() + NOTIFICATION_MARGIN;
                    }
                    break;
                case ToastPosition.TopRight:
                    foreach (var currentNotification in topRightNotifications)
                    {
                        var positionRect = currentNotification.GetEditorWindowPosition(toastPosition);
                        currentNotification.UpdatePosition(positionRect, currentHeightOffset, deltaTime);
                        currentHeightOffset += currentNotification.GetHeight() + NOTIFICATION_MARGIN;
                    }
                    break;
                case ToastPosition.TopCenter:
                    foreach (var currentNotification in topCenterNotifications)
                    {
                        var positionRect = currentNotification.GetEditorWindowPosition(toastPosition);
                        currentNotification.UpdatePosition(positionRect, currentHeightOffset, deltaTime);
                        currentHeightOffset += currentNotification.GetHeight() + NOTIFICATION_MARGIN;
                    }
                    break;
                case ToastPosition.BottomLeft:
                    foreach (var currentNotification in bottomLeftNotifications)
                    {
                        var positionRect = currentNotification.GetEditorWindowPosition(toastPosition);
                        currentNotification.UpdatePosition(positionRect, currentHeightOffset, deltaTime);
                        currentHeightOffset -= currentNotification.GetHeight() + NOTIFICATION_MARGIN;
                    }
                    break;
                case ToastPosition.BottomRight:
                    foreach (var currentNotification in bottomRightNotifications)
                    {
                        var positionRect = currentNotification.GetEditorWindowPosition(toastPosition);
                        currentNotification.UpdatePosition(positionRect, currentHeightOffset, deltaTime);
                        currentHeightOffset -= currentNotification.GetHeight() + NOTIFICATION_MARGIN;
                    }
                    break;
                case ToastPosition.BottomCenter:
                    foreach (var currentNotification in bottomCenterNotifications)
                    {
                        var positionRect = currentNotification.GetEditorWindowPosition(toastPosition);
                        currentNotification.UpdatePosition(positionRect, currentHeightOffset, deltaTime);
                        currentHeightOffset -= currentNotification.GetHeight() + NOTIFICATION_MARGIN;
                    }
                    break;
                default:
                    throw new ArgumentOutOfRangeException(nameof(toastPosition), toastPosition, null);
            }
        }
    }
}