using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Threading.Tasks;
using UnityEngine;
using UnityEngine.Events;
using UnityEngine.Networking;
using UnityEngine.SceneManagement;
using XFramework;
public static class AssetBundleHelper 
{
    static Dictionary<string, AssetBundle> bundles = new Dictionary<string, AssetBundle>();
    static Dictionary<string, Object> prefabs = new Dictionary<string, Object>();

    public static UnityWebRequest sceneWebRequest;


    //public static IEnumerator LoadGOAB<T>(string url, string objName, UnityAction<T> loadedAction) where T : Object
    //{
    //    if (!bundles.ContainsKey(url))
    //    {
    //       var goWebRequest = UnityWebRequestAssetBundle.GetAssetBundle(url);
    //        yield return goWebRequest.SendWebRequest();
    //        if (goWebRequest.error != null)
    //        {
    //            loadedAction.Invoke(null);
    //            yield return null;
    //        }
    //        AssetBundle ab = DownloadHandlerAssetBundle.GetContent(goWebRequest);
    //        bundles.Add(url, ab);
    //    }
    //    T go;
    //    if (!prefabs.ContainsKey(objName))
    //    {
    //        go = bundles[url].LoadAsset<T>(objName);
    //        prefabs.Add(objName, go);
    //    }
    //    else
    //        go = prefabs[objName] as T;
    //    loadedAction?.Invoke(go);
    //}

    /// <summary>
    /// await调用 加载AB包 预制件
    /// </summary>
    /// <param name="path">AB包路径</param>
    /// <param name="prefabName">预制件名称</param>
    /// <returns>预制件</returns>
    public static async Task<GameObject> LoadABPrefab(string path,string prefabName)
    {

#if UNITY_EDITOR
        //string eidtorPath = $"Assets/AssetBundlePrefab/{prefabName}.prefab";
        //if (!File.Exists(eidtorPath))
        //{
        //    Debug.LogError($"不存在的资源：{eidtorPath}，无法加载！");
        //    return null;
        //}
        //GameObject go = UnityEditor.AssetDatabase.LoadAssetAtPath<GameObject>(eidtorPath);
        //return go;
#endif
        if (prefabs.ContainsKey(path))
            return prefabs[path] as GameObject;
        //if (!bundles.ContainsKey(path))
        //{
            
        //}
        var task = LoadAsync(path, prefabName);
        Task<GameObject> t = await Task.WhenAny(task);
        return t.Result;
    }

    static async Task<GameObject> LoadAsync(string url,string prefabName)
    {
        //string path = Path.Combine(Application.streamingAssetsPath, url + end);
        var goWebRequest = UnityWebRequestAssetBundle.GetAssetBundle(url);
        await goWebRequest.SendWebRequest();
        if (goWebRequest.error != null)
        {
            Debug.Log($"资源：{url}加载失败，{goWebRequest.error}");
            return null;
        }
        AssetBundle ab = DownloadHandlerAssetBundle.GetContent(goWebRequest);
        GameObject go = ab.LoadAsset<GameObject>(prefabName);
        prefabs.Add(url, go);
        return go;
    }

    /// <summary>
    /// 加载场景AB包
    /// </summary>
    /// <param name="url">场景AB包路径</param>
    /// <param name="sceneLoaded"></param>
    /// <returns></returns>
    public static IEnumerator LoadSceneAB(string url, UnityAction sceneLoaded)
    {
        if (!bundles.ContainsKey(url))
        {
            //UnityWebRequest
           sceneWebRequest = UnityWebRequestAssetBundle.GetAssetBundle(url);
            Debug.Log("尝试加载文件");
            yield return sceneWebRequest.SendWebRequest();
           // Debug.Log(sceneWebRequest.error);
            Debug.Log("获取AssetBundle");
            AssetBundle ab = DownloadHandlerAssetBundle.GetContent(sceneWebRequest);
            bundles.Add(url, ab);
        }
        sceneLoaded?.Invoke();
    }

    /// <summary>
    /// 释放所有的资源 
    /// </summary>
    /// <param name="unloadAllLoadedObjects"> true 卸载所有AB资源，false 卸载当前不用资源</param>
    public static void UnloadAllAB(bool unloadAllLoadedObjects)
    {
        foreach (var item in bundles)
        {
            item.Value.Unload(unloadAllLoadedObjects);
        }
        bundles.Clear();
        prefabs.Clear();
        AssetBundle.UnloadAllAssetBundles(unloadAllLoadedObjects);
        Resources.UnloadUnusedAssets();
        System.GC.Collect();
    }
}