using UnityEditor;
using UnityEngine;
using UnityEngine.UIElements;
using System.Linq;
using System;
using System.IO;
using System.Collections.Generic;
using UnityEditor.SceneManagement;
using UXScroller = UnityEngine.UIElements.Scroller;

namespace AlicizaX.UXTool
{
    public static class PrefabTabs
    {
        public static readonly int m_maxCharacters = 20;
        public static readonly int m_minCharacters = 13;
        public static readonly int m_maxWidth = 150;
        public static readonly int m_minWidth = 100;

        public static VisualElement prefabTabsPanel;
        private static ScrollView TabsList;
        private static List<string> m_tabs;
        private static string m_selectedTab;
        private static SceneView sceneView = SceneView.lastActiveSceneView;
        private static int width;

        public static string SelectedGuid
        {
            get { return m_selectedTab; }
            set
            {
                m_selectedTab = value;
                EditorPrefs.SetString("AlicizaUXTool_SelectedTab", value); // 记录当前选中的Tab
            }
        }

        [InitializeOnLoadMethod]
        public static void Initialize()
        {
            UXDesinUtil.OnEnterDesignMode += RegisterEvents;
            UXDesinUtil.OnExitDesignMode += UnRegisterEvents;

            if (UXDesinUtil.InDesign)
            {
                RegisterEvents();
            }
            else
            {
                UnRegisterEvents();
            }
        }

        private static void RegisterEvents()
        {
            PrefabStageUtils.OnEditRootReplaced += OnEditRootReplaced;
            EditorApplication.delayCall += OnEditorLoaded;
            UXPrefabTabsConfig.Instance.SyncTabs();
        }

        private static void UnRegisterEvents()
        {
            PrefabStageUtils.OnEditRootReplaced -= OnEditRootReplaced;
            EditorApplication.delayCall -= OnEditorLoaded;
        }

        private static void OnEditorLoaded()
        {
            if (UXDesinUtil.InDesign)
            {
                CreateGUI();
                RefreshTabs(false, 0);
                OpenOrFallbackToLastValidTab();
            }
        }

        private static void OnEditRootReplaced(string assetPath)
        {
            string guid = AssetDatabase.AssetPathToGUID(assetPath);
            SelectedGuid = guid;
            RefreshTabs(false, 0);
        }

        private static void CreateGUI()
        {
            sceneView = SceneView.lastActiveSceneView;

            if (sceneView == null) return;

            prefabTabsPanel = new VisualElement();
            prefabTabsPanel.name = "Tabs";
            prefabTabsPanel.style.height = new StyleLength(new Length(100, LengthUnit.Percent));
            prefabTabsPanel.style.position = Position.Relative;
            prefabTabsPanel.style.top = 0;
            prefabTabsPanel.style.right = 0;
            prefabTabsPanel.style.left = 0;
            prefabTabsPanel.style.backgroundColor = new Color(48f / 255f, 48f / 255f, 48f / 255f); // rgb(48, 48, 48)
            prefabTabsPanel.style.flexGrow = 0;
            prefabTabsPanel.style.paddingRight = 0;
            prefabTabsPanel.style.marginRight = 160;

            TabsList = new ScrollView(ScrollViewMode.Horizontal);
            TabsList.name = "TabsList";
            TabsList.horizontalScrollerVisibility = ScrollerVisibility.AlwaysVisible;
            TabsList.verticalScrollerVisibility = ScrollerVisibility.Hidden;


            prefabTabsPanel.Add(TabsList);

            prefabTabsPanel.style.flexGrow = 1;
            prefabTabsPanel.style.height = Length.Percent(50);
            prefabTabsPanel.contentContainer.RegisterCallback<MouseLeaveEvent>((e) =>
            {
                Vector2 old = TabsList.scrollOffset;
                TabsList.scrollOffset = old;
                width = m_tabs.Count == 0 ? m_minWidth : Math.Min(Math.Max(m_minWidth, (int)sceneView.position.width / m_tabs.Count), m_maxWidth);
                RefreshTabs(false, 0);
            });
            UXScroller scroller = TabsList.horizontalScroller;
            scroller.Remove(scroller.lowButton);
            scroller.Remove(scroller.highButton);
            scroller.slider.style.height = 4;
            scroller.slider.style.marginBottom = 0;
            scroller.slider.style.paddingBottom = 0;
            scroller.slider.style.marginLeft = scroller.slider.style.marginRight = 0;
            scroller.style.height = 5;
            scroller.style.bottom = 0;
            scroller.style.marginBottom = 0;

            var parent = sceneView.rootVisualElement.parent.parent.parent.parent.parent.Q<IMGUIContainer>();
            if (parent != null) parent.Add(prefabTabsPanel);
            parent.style.flexShrink = 1;
            parent.style.width = Length.Percent(100);
            parent.style.flexGrow = 0.08f;
            parent.style.height = Length.Percent(5);

            m_tabs = UXPrefabTabsConfig.Instance.tabs;
            m_selectedTab = EditorPrefs.GetString("AlicizaUXTool_SelectedTab", string.Empty);
            if (m_tabs.Find(p => p == m_selectedTab) == null) m_selectedTab = string.Empty;
            RefreshTabs(false, 0); // 初始化时刷新 Tabs
        }

        public static void RefreshTabs(bool isclose, int width)
        {
            if (prefabTabsPanel == null) return;
#if UNITY_2021_3_OR_NEWER
            prefabTabsPanel.style.top = 0;
#else
            prefabTabsPanel.style.top = string.IsNullOrEmpty(m_selectedTab) ? 21 : 46;
#endif
            bool flag = TabsList.contentContainer.childCount == m_tabs.Count;
            TabsList.Clear();
            Button selectButton = null;
            foreach (var item in m_tabs)
            {
                string path = AssetDatabase.GUIDToAssetPath(item);
                if (path != "" && File.Exists(path))
                {
                    var tab = new PrefabSingleTab(new FileInfo(path), item, m_tabs.Count, isclose, width);
                    if (item == m_selectedTab)
                    {
                        tab.visual.style.backgroundColor = new Color(95f / 255, 95f / 255, 95f / 255, 1);
                        selectButton = tab.visual;
                    }
                    else
                    {
                        tab.visual.style.backgroundColor = new Color(60f / 255, 60f / 255, 60f / 255, 1);
                    }

                    TabsList.Add(tab.visual);
                }
            }

            if (selectButton != null)
            {
                if (flag)
                {
                    selectButton.RegisterCallback<GeometryChangedEvent, VisualElement>(FirstLayoutCallback, selectButton);
                }
                else
                {
                    TabsList.contentContainer.RegisterCallback<GeometryChangedEvent, VisualElement>(FirstLayoutCallback, selectButton);
                }
            }

            UXPrefabTabsConfig.Instance.tabs = m_tabs; // 保存当前 Tabs 状态
            UXPrefabTabsConfig.Save(); // 保存到磁盘
        }

        private static void OpenOrFallbackToLastValidTab()
        {
            // 尝试打开当前选中的GUID
            if (!string.IsNullOrEmpty(m_selectedTab) && m_tabs.Contains(m_selectedTab))
            {
                PrefabStageUtils.SwitchStage(AssetDatabase.GUIDToAssetPath(m_selectedTab));
            }
            else
            {
                // 移除不存在的GUID并选中最后一个有效的
                m_tabs.RemoveAll(guid =>
                {
                    string path = AssetDatabase.GUIDToAssetPath(guid);
                    return string.IsNullOrEmpty(path) || !File.Exists(path);
                });

                if (m_tabs.Count > 0)
                {
                    m_selectedTab = m_tabs.Last();
                    PrefabStageUtils.SwitchStage(AssetDatabase.GUIDToAssetPath(m_selectedTab));
                }
                else
                {
                    m_selectedTab = string.Empty;
                    PrefabStageUtils.OpenDefaultStage();
                }
            }

            RefreshTabs(false, 0);
        }


        public static void OpenTab(string guid, bool replaceRoot)
        {
            SelectedGuid = guid;
            if (replaceRoot)
            {
                PrefabStageUtils.SwitchStage(AssetDatabase.GUIDToAssetPath(guid));
            }

            if (!m_tabs.Contains(guid))
            {
                m_tabs.Add(guid);
                width = Math.Min(Math.Max(m_minWidth, (int)sceneView.position.width / m_tabs.Count), m_maxWidth);
            }

            RefreshTabs(false, 0);
        }

        public static void CloseTab(string guid)
        {
            m_tabs.Remove(guid);
            OpenOrFallbackToLastValidTab();
        }

        private static void FirstLayoutCallback(GeometryChangedEvent evt, VisualElement v)
        {
            if (!TabsList.Contains(v)) return;
            TabsList.ScrollTo(v);
        }
    }
}