using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.AddressableAssets;
using UnityEngine.Events;
using UnityEngine.ResourceManagement.AsyncOperations;

public class ResMgr : Singleton<ResMgr>
{
    public T Load<T>(string name)where T:Object
    {
        T res = Resources.Load<T>(name);
        if (res is GameObject)
            return Object.Instantiate(res);
        else
            return res;
    }
    public T Load<T>(string name,Vector3 position,Quaternion rotation) where T : Object
    {
        T res = Resources.Load<T>(name);
        if (res is GameObject)
            return Object.Instantiate(res, position, rotation);
        else
            return res;
    }
    public void LoadAsync<T>(string name,UnityAction<T> callback)where T:Object
    {
        MonoMgr.Instance.StartCoroutine(ReallyLoadAsync(name,callback));
    }
    private IEnumerator ReallyLoadAsync<T>(string name,UnityAction<T> callback)where T:Object
    {
        ResourceRequest r = Resources.LoadAsync<T>(name);
        yield return r;
        if (r.asset is GameObject)
        {
            callback(Object.Instantiate(r.asset) as T);
        }
        else
        {
            callback(r.asset as T);
        }
    }
    #region 异步加载使用方法（得到加载物体并设定位置等）
    //需要注意的是，异步加载中，调用异步加载后，物体并没有被加载，需要等n帧才会被加载，所以我们不能直接返回物体，而是在方法中将物体传出去。
    //private void Update()
    //{
    //    if (Input.GetMouseButtonDown(1))
    //    {
    //        ResMgr.Instance.LoadAsync<GameObject>("cube", DoSome);
    //    }
    //}
    //private void DoSome(GameObject obj)
    //{
    //    Debug.Log("调用了回调函数");
    //}
    ////为了方便，我们还可以直接使用Lambda表达式来方便书写
    //private void Update()
    //{
    //    if (Input.GetMouseButtonDown(1))
    //    {
    //        ResMgr.GetInstance().LoadAsync<GameObject>("cube", (obj) =>
    //        {
    //            Debug.Log("调用了回调函数");
    //        });
    //    }
    //}
    #endregion


    //Addressable
    public void AALoadAsync<T>(string name, UnityAction<T> callback) where T : Object
    {
        MonoMgr.Instance.StartCoroutine(AAReallyLoadAsync(name, callback));
    }
    private IEnumerator AAReallyLoadAsync<T>(string name, UnityAction<T> callback) where T : Object
    {
        AsyncOperationHandle async = Addressables.LoadAssetAsync<T>(name);
        yield return async;
        if (async.Result is GameObject)
        {
            callback(Object.Instantiate(async.Result as GameObject) as T);
        }
        else
        {
            callback(async.Result as T);
        }
    }
}