using UnityEngine;
using UnityEditor;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using UnityEditor.SceneManagement;

public class FavoritesTab : EditorWindow
{
    private List<UnityEngine.Object> favoriteObjects = new List<UnityEngine.Object>();
    private Vector2 scrollPosition;
    private bool showPrefabs = true;
    private bool showScenes = true;
    private bool showScripts = true;
    private bool showOthers = true;
    private string searchFilter = "";
    
    private const string FAVORITES_FILE = "Library/FavoritesData.json";
    
    [System.Serializable]
    public class FavoritesData
    {
        public List<string> favoritePaths = new List<string>();
    }
    
    [MenuItem("Window/Favorites Tab")]
    public static void ShowWindow()
    {
        GetWindow<FavoritesTab>("Favorites");
    }
    
    private void OnEnable()
    {
        LoadFavorites();
    }
    
    private void OnDisable()
    {
        SaveFavorites();
    }
    
    private void OnGUI()
    {
        DrawHeader();
        DrawFilters();
        DrawSearchBar();
        DrawFavoritesList();
        DrawDropArea();
        
        // Handle drag and drop
        HandleDragAndDrop();
    }
    
    private void DrawHeader()
    {
        EditorGUILayout.BeginHorizontal();
        GUILayout.Label("Favorites", EditorStyles.boldLabel);
        
        GUILayout.FlexibleSpace();
        
        if (GUILayout.Button("Clear All", GUILayout.Width(80)))
        {
            if (EditorUtility.DisplayDialog("Clear Favorites", "Are you sure you want to clear all favorites?", "Yes", "No"))
            {
                favoriteObjects.Clear();
                SaveFavorites();
            }
        }
        
        EditorGUILayout.EndHorizontal();
        EditorGUILayout.Space();
    }
    
    private void DrawFilters()
    {
        EditorGUILayout.BeginHorizontal();
        GUILayout.Label("Show:", GUILayout.Width(40));
        
        showPrefabs = GUILayout.Toggle(showPrefabs, "Prefabs", GUILayout.Width(60));
        showScenes = GUILayout.Toggle(showScenes, "Scenes", GUILayout.Width(60));
        showScripts = GUILayout.Toggle(showScripts, "Scripts", GUILayout.Width(60));
        showOthers = GUILayout.Toggle(showOthers, "Others", GUILayout.Width(60));
        
        EditorGUILayout.EndHorizontal();
        EditorGUILayout.Space();
    }
    
    private void DrawSearchBar()
    {
        EditorGUILayout.BeginHorizontal();
        GUILayout.Label("Search:", GUILayout.Width(50));
        searchFilter = EditorGUILayout.TextField(searchFilter);
        
        if (GUILayout.Button("X", GUILayout.Width(20)))
        {
            searchFilter = "";
            GUI.FocusControl(null);
        }
        
        EditorGUILayout.EndHorizontal();
        EditorGUILayout.Space();
    }
    
    private void DrawFavoritesList()
    {
        if (favoriteObjects.Count == 0)
        {
            EditorGUILayout.HelpBox("No favorites added yet. Drag assets here to add them to your favorites!", MessageType.Info);
            return;
        }
        
        scrollPosition = EditorGUILayout.BeginScrollView(scrollPosition);
        
        var filteredObjects = GetFilteredObjects();
        
        for (int i = 0; i < filteredObjects.Count; i++)
        {
            var obj = filteredObjects[i];
            if (obj == null) continue;
            
            DrawFavoriteItem(obj, i);
        }
        
        EditorGUILayout.EndScrollView();
    }
    
    private List<UnityEngine.Object> GetFilteredObjects()
    {
        var filtered = favoriteObjects.Where(obj => obj != null).ToList();
        
        // Apply type filters
        if (!showPrefabs || !showScenes || !showScripts || !showOthers)
        {
            filtered = filtered.Where(obj => ShouldShowObject(obj)).ToList();
        }
        
        // Apply search filter
        if (!string.IsNullOrEmpty(searchFilter))
        {
            filtered = filtered.Where(obj => obj.name.ToLower().Contains(searchFilter.ToLower())).ToList();
        }
        
        return filtered;
    }
    
    private bool ShouldShowObject(UnityEngine.Object obj)
    {
        var path = AssetDatabase.GetAssetPath(obj);
        var extension = Path.GetExtension(path).ToLower();
        
        if (showPrefabs && extension == ".prefab") return true;
        if (showScenes && (extension == ".unity" || obj is SceneAsset)) return true;
        if (showScripts && (extension == ".cs" || extension == ".js")) return true;
        if (showOthers && extension != ".prefab" && extension != ".unity" && extension != ".cs" && extension != ".js") return true;
        
        return false;
    }
    
    private void DrawFavoriteItem(UnityEngine.Object obj, int index)
    {
        EditorGUILayout.BeginHorizontal();
        
        // Icon
        var icon = AssetPreview.GetMiniThumbnail(obj);
        if (icon != null)
        {
            GUILayout.Label(icon, GUILayout.Width(20), GUILayout.Height(20));
        }
        
        // Object field (clickable)
        var newObj = EditorGUILayout.ObjectField(obj, typeof(UnityEngine.Object), false);
        if (newObj != obj)
        {
            favoriteObjects[favoriteObjects.IndexOf(obj)] = newObj;
            SaveFavorites();
        }
        
        // Quick action buttons
        var path = AssetDatabase.GetAssetPath(obj);
        var extension = Path.GetExtension(path).ToLower();
        
        if (extension == ".unity" || obj is SceneAsset)
        {
            if (GUILayout.Button("Open", GUILayout.Width(50)))
            {
                if (EditorSceneManager.SaveCurrentModifiedScenesIfUserWantsTo())
                {
                    EditorSceneManager.OpenScene(path);
                }
            }
        }
        else if (extension == ".prefab")
        {
            if (GUILayout.Button("Select", GUILayout.Width(50)))
            {
                Selection.activeObject = obj;
                EditorGUIUtility.PingObject(obj);
            }
        }
        else if (extension == ".cs")
        {
            if (GUILayout.Button("Edit", GUILayout.Width(50)))
            {
                AssetDatabase.OpenAsset(obj);
            }
        }
        
        // Remove button
        if (GUILayout.Button("X", GUILayout.Width(20)))
        {
            favoriteObjects.Remove(obj);
            SaveFavorites();
        }
        
        EditorGUILayout.EndHorizontal();
    }
    
    private void DrawDropArea()
    {
        EditorGUILayout.Space();
        
        var dropArea = GUILayoutUtility.GetRect(0.0f, 50.0f, GUILayout.ExpandWidth(true));
        GUI.Box(dropArea, "Drag assets here to add to favorites");
        
        switch (Event.current.type)
        {
            case EventType.DragUpdated:
            case EventType.DragPerform:
                if (!dropArea.Contains(Event.current.mousePosition))
                    break;
                
                DragAndDrop.visualMode = DragAndDropVisualMode.Copy;
                
                if (Event.current.type == EventType.DragPerform)
                {
                    DragAndDrop.AcceptDrag();
                    
                    foreach (var draggedObject in DragAndDrop.objectReferences)
                    {
                        AddToFavorites(draggedObject);
                    }
                }
                break;
        }
    }
    
    private void HandleDragAndDrop()
    {
        if (Event.current.type == EventType.DragUpdated)
        {
            DragAndDrop.visualMode = DragAndDropVisualMode.Copy;
            Event.current.Use();
        }
        else if (Event.current.type == EventType.DragPerform)
        {
            DragAndDrop.AcceptDrag();
            
            foreach (var draggedObject in DragAndDrop.objectReferences)
            {
                AddToFavorites(draggedObject);
            }
            
            Event.current.Use();
        }
    }
    
    private void AddToFavorites(UnityEngine.Object obj)
    {
        if (obj == null) return;
        
        if (!favoriteObjects.Contains(obj))
        {
            favoriteObjects.Add(obj);
            SaveFavorites();
        }
    }
    
    private void SaveFavorites()
    {
        var data = new FavoritesData();
        
        foreach (var obj in favoriteObjects)
        {
            if (obj != null)
            {
                var path = AssetDatabase.GetAssetPath(obj);
                if (!string.IsNullOrEmpty(path))
                {
                    data.favoritePaths.Add(path);
                }
            }
        }
        
        var json = JsonUtility.ToJson(data, true);
        File.WriteAllText(FAVORITES_FILE, json);
    }
    
    private void LoadFavorites()
    {
        favoriteObjects.Clear();
        
        if (File.Exists(FAVORITES_FILE))
        {
            try
            {
                var json = File.ReadAllText(FAVORITES_FILE);
                var data = JsonUtility.FromJson<FavoritesData>(json);
                
                foreach (var path in data.favoritePaths)
                {
                    UnityEngine.Object obj = null;
                    
                    // Handle scenes specifically
                    if (path.EndsWith(".unity"))
                    {
                        obj = AssetDatabase.LoadAssetAtPath<SceneAsset>(path);
                    }
                    else
                    {
                        obj = AssetDatabase.LoadAssetAtPath<UnityEngine.Object>(path);
                    }
                    
                    if (obj != null)
                    {
                        favoriteObjects.Add(obj);
                    }
                }
            }
            catch (System.Exception e)
            {
                Debug.LogError($"Error loading favorites: {e.Message}");
            }
        }
    }
}