using UnityEngine;
using System.Collections.Generic;
using System;
using UnityEngine.U2D;
using System.IO;
using UnityEngine.Video;
using Spine.Unity;
using UnityEngine.UI;
using Cysharp.Threading.Tasks;
using System.Threading;
using ProjSG.Resource;





#if UNITY_EDITOR
using UnityEditor;
#endif

using LaunchCommon;

public class ResManager : Singleton<ResManager>
{
    

    //不下载时本地安卓测试路径
    // public string assetBundlesPath = Application.dataPath + "/../AssetBundles/Android/";
    // public static string bytesFolderName = "logicbytes/";
    public string StreamingAssetPath
    {
        get
        {
            return ResourcesPath.Instance.StreamingAssetPath;
        }
    }
    public string ExternalStorePath 
    {
        get
        {
            return ResourcesPath.Instance.ExternalStorePath;
        }
    }

    //用于editor 下的资源路径
    public string ResourcesOutPath 
    {
        get
        {
            return ResourcesPath.ResourcesOutPath;
        }
    }

    public string CONFIG_FODLER
    {
        get
        {
            return ResourcesPath.CONFIG_FODLER;
        }
    }

    public string ResourcesOutAssetPath
    {
        get
        {
            return ResourcesPath.ResourcesOutAssetPath;
        }
    }
    
    private static readonly Dictionary<Type, string> fileExtensionDict = new Dictionary<Type, string>()
    {
        {typeof(GameObject), "prefab"},
        {typeof(Sprite), "png"},
        {typeof(Texture2D), "jpg"},
        {typeof(Texture), "jpg"},
        {typeof(Shader), "shader"},
        {typeof(TextAsset), "txt"},
        {typeof(AudioClip), "wav"},
        {typeof(Font), "ttf"},
        {typeof(Material), "mat"},
        {typeof(VideoClip), "mp4"},
        {typeof(SpriteAtlas), "spriteatlasv2"},
        {typeof(SkeletonDataAsset), "asset"},
    };


    public void Init()
    {

    }

    public void Release()
    {

    }
    
    private string GetExtension(Type type)
    {
        if (fileExtensionDict.TryGetValue(type, out string extension))
            return "." + extension;
        else
        {
            Debug.LogErrorFormat("GetExtension() => 不支持的资源类型: {0}.", type.Name);
            return "";
        }
    }

#if UNITY_EDITOR
    public string GetFullDirectory(string directory)
    {
        string fullDirectory = Path.Combine(ResourcesOutPath, directory);
        return fullDirectory;
    }

    public string FindFilePath(string directory, string fileName)
    {
        string[] files = Directory.GetFiles(GetFullDirectory(directory), fileName, SearchOption.AllDirectories);
        if (files.Length > 0)
        {
            return files[0];
        }
        return string.Empty;
    }

    public string GetRelativePath(string absolutePath)
    {
        string relativePath = absolutePath.Replace(ResourcesOutPath, "Assets/ResourcesOut/");
        return relativePath;
    }
#endif

    //needExt 是否需要函数内部添加后缀
    [System.Obsolete("US2: Use LoadAssetAsync<T>(directory, name, needExt) returning UniTask<T> instead.")]
    public T LoadAsset<T>(string directory, string name, bool needExt = true) where T : UnityEngine.Object
    {
        directory = directory.Replace("\\", "/");
        name = name.Replace("\\", "/");
        //  特殊处理 因为有一层图集的关系 directory要传入的应该是atlas的名字
        if (typeof(T) == typeof(Sprite))
        {
            return LoadSprite(directory, name) as T;
        }
        else if (typeof(T) == typeof(SkeletonDataAsset))
        {
            //文件目录调整，name中包含了路径
            if (name.Contains("/"))
            {
                directory += name.Substring(0, name.LastIndexOf("/"));
                name = name.Substring(name.LastIndexOf("/") + 1);
            }

        }

        return LoadAssetInternal<T>(directory, name, needExt);
    }

    //needExt 是否需要函数内部添加后缀
    private T LoadAssetInternal<T>(string directory, string name, bool needExt = true) where T : UnityEngine.Object
    {
        T asset = null;
        var path = ($"Assets/ResourcesOut/{directory}/{name}" + (needExt ? GetExtension(typeof(T)) : "")).Replace("//", "/").Trim().Replace("\\", "/");

        if (!AssetSource.isUseAssetBundle)
        {
#if UNITY_EDITOR
            asset = UnityEditor.AssetDatabase.LoadAssetAtPath<T>(path);
#endif
        }
        else
        {
            // US1: Route through YooAssetService sync wrapper (transitional)
            #pragma warning disable CS0612, CS0618
            asset = YooAssetService.Instance.LoadAssetSync<T>(path);
            #pragma warning restore CS0612, CS0618
        }

        if (asset == null)
        {
            Debug.LogErrorFormat("LoadAsset() => 加载不到资源: {0}", path);
        }

        return asset;
    }

    [System.Obsolete("US2: Use LoadConfigAsync returning UniTask<string[]> instead.")]
    public string[] LoadConfig(string name)
    {
        string path = string.Empty;
#if UNITY_EDITOR
        if (!AssetSource.isUseAssetBundle)
        {
            path = ResourcesPath.CONFIG_FODLER + "/" + name + ".txt";
        }
        else
#endif
        {
            path = AssetVersionUtility.GetAssetFilePath($"config/{name}.txt");
        }

        return File.ReadAllLines(path);
    }

    private Sprite LoadSprite(string atlasName, string spriteName)
    {
        if (!AssetSource.isUseAssetBundle)
        {
            #pragma warning disable CS0618 // Obsolete — legacy sync fallback
            SpriteAtlas atlas = LoadAsset<SpriteAtlas>("Sprite", atlasName.Replace("Sprite/", ""));
            #pragma warning restore CS0618
            if (null == atlas)
            {
                return null;
            }
            return atlas.GetSprite(spriteName);
        }
        else
            return LoadAssetInternal<Sprite>(atlasName, spriteName);
    }

    //needExt 是否需要函数内部添加后缀
    [System.Obsolete("US2: Use LoadAssetAsync<T>(directory, name, needExt) returning UniTask<T> instead.")]
    public void LoadAssetAsync<T>(string directory, string name, Action<bool, UnityEngine.Object> callBack, bool needExt = true) where T : UnityEngine.Object
    {
        directory = directory.Replace("\\", "/");
        name = name.Replace("\\", "/");

        //  特殊处理 因为有一层图集的关系 directory要传入的应该是atlas的名字
        if (typeof(T) == typeof(Sprite))
        {
            LoadSpriteAsync<T>(directory, name, callBack);
            return;
        }

        LoadAssetAsyncInternal<T>(directory, name, callBack, needExt);
    }

    private void LoadSpriteAsync<T>(string atlasName, string spriteName, Action<bool, UnityEngine.Object> callBack) where T : UnityEngine.Object
    {
        if (!AssetSource.isUseAssetBundle)
        {
            // Editor 模式下可直接加载 sprite
            LoadAssetAsyncInternal<T>(atlasName, spriteName, callBack);
        }
        else
        {
            // AB 模式下直接加载单独的 Sprite 文件（YooAsset 自动处理 SpriteAtlas 依赖）
            LoadAssetAsyncInternal<Sprite>(atlasName, spriteName, (isLoaded, sprite) =>
            {
                callBack?.Invoke(isLoaded, sprite);
            });
        }
    }

    private void LoadAssetAsyncInternal<T>(string directory, string name, Action<bool, UnityEngine.Object> callBack, bool needExt = true) where T : UnityEngine.Object
    {
        var path = string.Concat($"Assets/ResourcesOut/{directory}/{name}", (needExt ? GetExtension(typeof(T)) : "")).Replace("//", "/");

        if (!AssetSource.isUseAssetBundle)
        {
#if UNITY_EDITOR
            var asset = UnityEditor.AssetDatabase.LoadAssetAtPath<T>(path);
            callBack?.Invoke(asset != null, asset);
#endif
        }
        else
        {
            // US1: Route through YooAssetService async
            CoLoadViaYooAsset<T>(path, callBack).Forget();
        }
    }

    private async UniTaskVoid CoLoadViaYooAsset<T>(string path, Action<bool, UnityEngine.Object> callBack, CancellationToken ct = default) where T : UnityEngine.Object
    {
        try
        {
            var asset = await YooAssetService.Instance.LoadAssetAsync<T>(path, ct: ct);
            callBack?.Invoke(asset != null, asset);
        }
        catch (Exception ex)
        {
            Debug.LogError($"[ResManager] Async load via YooAsset failed: {ex.Message}");
            callBack?.Invoke(false, null);
        }
    }

    [System.Obsolete("US1: Use YooAssetService.ReleaseHandle or UnloadUnusedAssetsAsync instead.")]
    public void UnloadAsset(string assetBundleName, string assetName)
    {
        // US1: AssetBundleUtility unload no longer effective since assets loaded via YooAsset.
        // Proper unload handled via YooAssetService handle-based release.
    }

    [System.Obsolete("US1: Use YooAssetService.UnloadUnusedAssetsAsync instead.")]
    public void UnloadAssetBundle(string assetBundleName, bool unloadAllLoadedObjects, bool includeDependenice)
    {
        // US1: AssetBundleUtility unload no longer effective since assets loaded via YooAsset.
    }

    public string GetAssetFilePath(string _assetKey)
    {
        var path = Path.Combine(ExternalStorePath, _assetKey);
        if (!File.Exists(path))
        {
            path = Path.Combine(StreamingAssetPath, _assetKey);
        }

        return path;
    }

    // ====================================================================
    // US1: New UniTask-based async variants
    // ====================================================================

    /// <summary>
    /// 异步加载资源（UniTask 版本，US1 新增）。
    /// </summary>
    public async UniTask<T> LoadAssetAsync<T>(string directory, string name, bool needExt = true, CancellationToken ct = default) where T : UnityEngine.Object
    {
        directory = directory.Replace("\\", "/");
        name = name.Replace("\\", "/");

        if (typeof(T) == typeof(Sprite))
        {
            return await LoadSpriteAsyncUniTask(directory, name, ct) as T;
        }

        if (typeof(T) == typeof(SkeletonDataAsset))
        {
            if (name.Contains("/"))
            {
                directory += name.Substring(0, name.LastIndexOf("/"));
                name = name.Substring(name.LastIndexOf("/") + 1);
            }
        }

        var path = ($"Assets/ResourcesOut/{directory}/{name}" + (needExt ? GetExtension(typeof(T)) : ""))
            .Replace("//", "/").Trim().Replace("\\", "/");

        if (!AssetSource.isUseAssetBundle)
        {
#if UNITY_EDITOR
            return UnityEditor.AssetDatabase.LoadAssetAtPath<T>(path);
#else
            return null;
#endif
        }

        return await YooAssetService.Instance.LoadAssetAsync<T>(path, ct: ct);
    }

    /// <summary>
    /// US4: 异步加载资源并走缓存层（缓存命中直接返回，未命中则加载并缓存）。
    /// </summary>
    public async UniTask<T> LoadAssetCachedAsync<T>(string directory, string name, bool needExt = true, CancellationToken ct = default) where T : UnityEngine.Object
    {
        directory = directory.Replace("\\", "/");
        name = name.Replace("\\", "/");

        var path = ($"Assets/ResourcesOut/{directory}/{name}" + (needExt ? GetExtension(typeof(T)) : ""))
            .Replace("//", "/").Trim().Replace("\\", "/");

        if (!AssetSource.isUseAssetBundle)
        {
#if UNITY_EDITOR
            return UnityEditor.AssetDatabase.LoadAssetAtPath<T>(path);
#else
            return null;
#endif
        }

        return await ResourceCacheManager.Instance.GetOrLoadAsync<T>(path);
    }

    private async UniTask<Sprite> LoadSpriteAsyncUniTask(string atlasName, string spriteName, CancellationToken ct = default)
    {
        if (!AssetSource.isUseAssetBundle)
        {
            var atlas = await LoadAssetAsync<SpriteAtlas>("Sprite", atlasName.Replace("Sprite/", ""), ct: ct);
            return atlas?.GetSprite(spriteName);
        }
        else
        {
            var path = $"Assets/ResourcesOut/{atlasName}/{spriteName}.png"
                .Replace("//", "/").Trim().Replace("\\", "/");
            return await YooAssetService.Instance.LoadAssetAsync<Sprite>(path, ct: ct);
        }
    }

    /// <summary>
    /// 异步加载配置文件（UniTask 版本）。
    /// WebGL 平台使用 YooAsset RawFile 异步加载，其他平台使用线程池。
    /// </summary>
    public async UniTask<string[]> LoadConfigAsync(string name, CancellationToken ct = default)
    {
#if UNITY_WEBGL && !UNITY_EDITOR
        // WebGL 不支持多线程和 File.ReadAllLines，使用 YooAsset RawFile
        try
        {
            var text = await ProjSG.Resource.YooAssetService.Instance.LoadRawFileTextAsync($"config/{name}", ct);
            if (!string.IsNullOrEmpty(text))
            {
                return text.Split(new[] { "\r\n", "\n" }, System.StringSplitOptions.None);
            }
        }
        catch (System.Exception ex)
        {
            UnityEngine.Debug.LogError($"[ResManager] LoadConfigAsync WebGL fallback failed for '{name}': {ex.Message}");
        }
        return System.Array.Empty<string>();
#else
        #pragma warning disable CS0618 // LoadConfig is obsolete — used here as thread-pool fallback for non-WebGL
        return await UniTask.RunOnThreadPool(() => LoadConfig(name));
        #pragma warning restore CS0618
#endif
    }

}