#if UNITY_EDITOR
using System.Collections.Generic;
using System.Text;
using UnityEditor;
using UnityEditor.SceneManagement;
using UnityEngine;
using UnityEngine.SceneManagement;

public static class MissingScriptUtility
{
    [MenuItem("Tools/Diagnostics/Find Missing Scripts in Open Scenes")]
    public static void FindMissingScriptsInOpenScenes()
    {
        int missingCount = 0;
        var reported = new HashSet<GameObject>();

        foreach (var scene in GetLoadedScenes())
        {
            foreach (var root in scene.GetRootGameObjects())
                ScanHierarchy(root, ref missingCount, reported);
        }

        Debug.Log($"[MissingScriptUtility] Missing scripts found: {missingCount}");
    }

    [MenuItem("Tools/Diagnostics/Find Missing Scripts in Prefabs")]
    public static void FindMissingScriptsInPrefabs()
    {
        var prefabGuids = AssetDatabase.FindAssets("t:Prefab");
        int missingCount = 0;

        for (int i = 0; i < prefabGuids.Length; i++)
        {
            var path = AssetDatabase.GUIDToAssetPath(prefabGuids[i]);
            EditorUtility.DisplayProgressBar("Scanning Prefabs", path, (float)i / prefabGuids.Length);

            var root = PrefabUtility.LoadPrefabContents(path);
            if (root == null)
                continue;

            ScanHierarchy(root, ref missingCount, null, path);
            PrefabUtility.UnloadPrefabContents(root);
        }

        EditorUtility.ClearProgressBar();
        Debug.Log($"[MissingScriptUtility] Missing scripts found in prefabs: {missingCount}");
    }

    [MenuItem("Tools/Diagnostics/Remove Missing Scripts in Open Scenes")]
    public static void RemoveMissingScriptsInOpenScenes()
    {
        int removed = 0;

        foreach (var scene in GetLoadedScenes())
        {
            foreach (var root in scene.GetRootGameObjects())
                removed += GameObjectUtility.RemoveMonoBehavioursWithMissingScript(root);
        }

        if (removed > 0)
            EditorSceneManager.MarkAllScenesDirty();

        Debug.Log($"[MissingScriptUtility] Removed missing scripts: {removed}");
    }

    [MenuItem("Tools/Diagnostics/Remove Missing Scripts in Prefabs")]
    public static void RemoveMissingScriptsInPrefabs()
    {
        var prefabGuids = AssetDatabase.FindAssets("t:Prefab");
        int removed = 0;

        for (int i = 0; i < prefabGuids.Length; i++)
        {
            var path = AssetDatabase.GUIDToAssetPath(prefabGuids[i]);
            EditorUtility.DisplayProgressBar("Cleaning Prefabs", path, (float)i / prefabGuids.Length);

            var root = PrefabUtility.LoadPrefabContents(path);
            if (root == null)
                continue;

            int removedInPrefab = GameObjectUtility.RemoveMonoBehavioursWithMissingScript(root);
            if (removedInPrefab > 0)
                PrefabUtility.SaveAsPrefabAsset(root, path);

            removed += removedInPrefab;
            PrefabUtility.UnloadPrefabContents(root);
        }

        EditorUtility.ClearProgressBar();
        if (removed > 0)
            AssetDatabase.SaveAssets();

        Debug.Log($"[MissingScriptUtility] Removed missing scripts in prefabs: {removed}");
    }

    private static IEnumerable<Scene> GetLoadedScenes()
    {
        for (int i = 0; i < SceneManager.sceneCount; i++)
        {
            var scene = SceneManager.GetSceneAt(i);
            if (scene.isLoaded)
                yield return scene;
        }
    }

    private static void ScanHierarchy(GameObject go, ref int missingCount, HashSet<GameObject> reported, string assetPath = null)
    {
        var components = go.GetComponents<Component>();
        for (int i = 0; i < components.Length; i++)
        {
            if (components[i] == null)
            {
                missingCount++;
                if (reported == null || reported.Add(go))
                {
                    var label = string.IsNullOrWhiteSpace(assetPath) ? "scene object" : $"prefab {assetPath}";
                    Debug.LogWarning($"[MissingScriptUtility] Missing script on {label}: {GetHierarchyPath(go.transform)}");
                }
                break;
            }
        }

        foreach (Transform child in go.transform)
            ScanHierarchy(child.gameObject, ref missingCount, reported);
    }

    private static string GetHierarchyPath(Transform transform)
    {
        var sb = new StringBuilder(transform.name);
        while (transform.parent != null)
        {
            transform = transform.parent;
            sb.Insert(0, transform.name + "/");
        }
        return sb.ToString();
    }
}
#endif