using System.Collections.Generic;
using TyphoonGUIStyle;
using UnityEditor;
using UnityEditor.SceneManagement;
using UnityEngine;
using UnityEngine.SceneManagement;

namespace TyphoonUI
{
    [InitializeOnLoad]
    public class HierarchyDrawer
    {
        static HierarchyDrawer()
        {
            EditorApplication.hierarchyWindowItemOnGUI += OnHierarchyGUI;
            EditorSceneManager.activeSceneChangedInEditMode += OnSceneChanged;
            TyphoonUIEditorApplication.OnUIObjectOnNodesChanged += OnUIObjectOnNodesChanged;
            UIObject.OnInvokeAwake += AddUIObject;
            UIObject.OnInvokeDestroy += RemoveUIObject;
        }


        //清除缓存
        private static void OnSceneChanged(Scene arg0, Scene arg1)
        {
            _monitoring.Clear();
            _monitorUIObjectInstanceID.Clear();
            _monitorUIObjects.Clear();
            _status.Clear();
        }

        //导出状态
        private static Dictionary<int, HashSet<UIObject>> _status = new Dictionary<int, HashSet<UIObject>>();

        //监控队列
        private static HashSet<int> _monitoring = new HashSet<int>();

        //监控UIObject
        private static HashSet<UIObject> _monitorUIObjects = new HashSet<UIObject>();

        //监控的UIObject InstanceID
        private static HashSet<int> _monitorUIObjectInstanceID = new HashSet<int>();


        private static UIObject _focusObjs = null;
        private static int _focusObjsInstanceID = -1;

        private static void OnHierarchyGUI(int instanceID, Rect selectionRect)
        {
            if (EditorApplication.isPlaying && !Preferences.Default.DrawHierarchyInPlayingMode)
            {
                return;
            }

            if (EditorApplication.isCompiling)
            {
                return;
            }

            var target = EditorUtility.InstanceIDToObject(instanceID);
            if (target is GameObject)
            {
                var addMonitor = _monitoring.Add(instanceID);
                if (addMonitor)
                {
                    //添加成功，尝试获取UiObject
                    var go = (target as GameObject);
                    var com = go.GetComponent<UIObject>();
                    if (com != null)
                    {
                        AddUIObject(com);
                    }
                }

                //绘制gui
                var hasUIObject = HasUIObject(instanceID);
                var isExport = IsExportInstanceID(instanceID, out var match);
                if (hasUIObject || isExport)
                {
                    var isFocus = hasUIObject && (_focusObjs != null && instanceID == _focusObjsInstanceID);
                    isFocus |= isExport && (_focusObjs != null && match.Contains(_focusObjs));
                    if (isFocus)
                    {
                        GUI.DrawTexture(selectionRect, EditorIcons.focus_hierarchy);
                    }

                    var rectMark = selectionRect;
                    rectMark.width = rectMark.height;
                    rectMark.x = selectionRect.xMax - rectMark.width;
                    rectMark.x -= 2;
                    if (hasUIObject && Preferences.Default.DrawUIObjectHierarchy)
                    {
                        if (GUI.Button(rectMark, "", Styles.Btn))
                        {
                            var menu = new GenericMenu();
                            var obj = (target as GameObject).GetComponent<UIObject>();
                            if (_focusObjs == obj)
                            {
                                menu.AddItem(new GUIContent("关闭增强模式"), false,
                                    () =>
                                    {
                                        _focusObjs = null;
                                        _focusObjsInstanceID = -1;
                                    });
                            }
                            else
                            {
                                menu.AddItem(new GUIContent("开启增强模式"), false,
                                    () =>
                                    {
                                        _focusObjs = obj;
                                        _focusObjsInstanceID = _focusObjs.gameObject.GetInstanceID();
                                    });
                            }

                            menu.ShowAsContext();
                        }

                        if (isFocus)
                        {
                            GUI.DrawTexture(rectMark, EditorIcons.grid_focus);
                        }
                        else
                        {
                            GUI.DrawTexture(rectMark, EditorIcons.grid);
                        }
                    }

                    if (isExport && Preferences.Default.DrawUINodeHierarchy)
                    {
                        if (isFocus)
                        {
                            GUI.DrawTexture(rectMark, EditorIcons.degree_focus);
                        }
                        else
                        {
                            GUI.DrawTexture(rectMark, EditorIcons.degree);
                        }
                    }
                }
            }
        }


        private static void AddUIObject(UIObject obj)
        {
            //加入UIObject监控列表
            var success = _monitorUIObjects.Add(obj);
            if (success)
            {
                _monitorUIObjectInstanceID.Add(obj.gameObject.GetInstanceID());
                //更新status
                var instanceIDs = obj.GetRelatedInstanceID();
                foreach (var id in instanceIDs)
                {
                    AddStatus(id, obj);
                }
            }
        }

        private static void RemoveUIObject(UIObject obj)
        {
            var success = _monitorUIObjects.Remove(obj);
            if (success)
            {
                _monitorUIObjectInstanceID.Remove(obj.gameObject.GetInstanceID());
            }

            RemoveStatus(obj);
        }

        private static void RemoveStatus(UIObject obj)
        {
            foreach (var kv in _status)
            {
                kv.Value.Remove(obj);
            }
        }

        private static void AddStatus(int instanceID, UIObject obj)
        {
            if (!_status.ContainsKey(instanceID))
            {
                _status.Add(instanceID, new HashSet<UIObject>());
            }

            _status[instanceID].Add(obj);
        }

        private static bool IsExportInstanceID(int instanceId, out HashSet<UIObject> match)
        {
            if (_status.TryGetValue(instanceId, out match))
            {
                return match.Count > 0;
            }

            return false;
        }

        private static bool HasUIObject(int instanceId)
        {
            return _monitorUIObjectInstanceID.Contains(instanceId);
        }

        private static void OnUIObjectOnNodesChanged(UIObject obj)
        {
            RemoveStatus(obj);
            var relatedInstanceID = obj.GetRelatedInstanceID();
            foreach (var id in relatedInstanceID)
            {
                AddStatus(id, obj);
            }
        }
    }
}