#if UNITY_6000_3_OR_NEWER
using System;
using System.Collections.Generic;
using UnityEditor;
using UnityEditor.Toolbars;
using UnityEngine;
using UnityEngine.Scripting;

namespace Module.NavigationTool.Editor.Entities.Toolbar
{
    internal static class MainToolbarEntitiesElement
    {
        [Preserve]
        [MainToolbarElement("Toolbar/Entities", ussName = "", defaultDockIndex = 0, defaultDockPosition = MainToolbarDockPosition.Middle, menuPriority = 500)]
        public static IEnumerable<MainToolbarElement> Draw()
        {
            Styles.Initialize();
            
            return new List<MainToolbarElement>(5)
            {
                new MainToolbarButton(new MainToolbarContent(Styles.IconHierarchy, "Show/Hide entities hierarchy window"), () => ToggleWindow("HierarchyWindow")),
#if !UNITY_6000_5_OR_NEWER
                new MainToolbarButton(new MainToolbarContent(Styles.IconComponents, "Show/Hide entities components window"), () => ToggleWindow("ComponentsWindow")),
#endif
                new MainToolbarButton(new MainToolbarContent(Styles.IconSystems, "Show/Hide entities systems window"), () => ToggleWindow("SystemScheduleWindow")),
#if !UNITY_6000_5_OR_NEWER
                new MainToolbarButton(new MainToolbarContent(Styles.IconArchetypes, "Show/Hide entities archetypes window"), () => ToggleWindow("ArchetypesWindow")),
                new MainToolbarButton(new MainToolbarContent(Styles.IconJournaling, "Show/Hide entities journaling window"), () => ToggleWindow("EntitiesJournalingWindow"))
#endif
            };
        }
        
        private static void ToggleWindow(string typeName)
        {
            var fullname = $"{nameof(Unity)}.Entities.Editor.{typeName}, Unity.Entities.Editor";
            var type = Type.GetType(fullname, false, true);

            if (type != null)
            {
                var all = Resources.FindObjectsOfTypeAll(type);
                
                if (all.Length != 0)
                {
                    for (var i = 0; i < all.Length; i++)
                    {
                        if (all[i] is EditorWindow window)
                            window.Close();
                    }
                }
                else
                {
                    EditorWindow.GetWindow(type);
                }
            }
            else
            {
                Debug.LogWarningFormat("Failed to find type with name: {0}", fullname);
            }
        }

        private static class Styles
        {
            public static Texture2D IconHierarchy;
#if !UNITY_6000_5_OR_NEWER
            public static Texture2D IconComponents;
#endif
            public static Texture2D IconSystems;
#if !UNITY_6000_5_OR_NEWER
            public static Texture2D IconArchetypes;
            public static Texture2D IconJournaling;
#endif
            
            private static bool _isInitialized;
            
            private const string EditorDefaultResourcesPath = "Packages/com.unity.entities/Editor Default Resources/";
            private const string EditorIconsLightDirectory = EditorDefaultResourcesPath + "icons/light";
            private const string EditorIconsDarkDirectory = EditorDefaultResourcesPath + "icons/dark";

            public static void Initialize()
            {
                if (_isInitialized)
                    return;
                
                IconHierarchy = LoadIcon("EntityGroup/EntityGroup");
#if !UNITY_6000_5_OR_NEWER
                IconComponents = LoadIcon("Component/Component");
#endif
                IconSystems = LoadIcon("System/System");
#if !UNITY_6000_5_OR_NEWER
                IconArchetypes = LoadIcon("Archetype/Archetype");
                IconJournaling = LoadIcon("Journaling/Journaling");
#endif
                
                _isInitialized = true;
            }
            
            private static Texture2D LoadIcon(string name)
            {
                var iconsDirectory = EditorIconsLightDirectory;
                
                if (EditorGUIUtility.isProSkin)
                    iconsDirectory = EditorIconsDarkDirectory;
                
                var obj = AssetDatabase.LoadAssetAtPath($"{iconsDirectory}/{name}.png", typeof(Texture2D));
                return obj != null ? (Texture2D)obj : null;
            }
        }
    }
}
#endif