using System;
using UnityEngine;
using UnityEngine.SceneManagement;
using KFADA = XGame.Framework.Asyncs;

namespace XGame.Framework.Asset
{
    public class SceneAsyncOperation<T> : KFADA.ResultAsync<T>
    {
        public object SceneAsset;

        private string _sceneName;
        private IAssetModule _assetModule;
        private AsyncOperation _async;
        private KFADA.IAsync _abAsync;
        private float _abProgress = 0.5f;

        public override float Progress
        {
            get
            {
                if (_abAsync != null || _async != null) return _abProgress;
                else
                {
                    if (!IsCompleted)
                        return _abProgress + _async.progress / 2;
                    else
                        return 1.0f;
                }
            }
        }

        public SceneAsyncOperation(string sceneName, IAssetModule assetModule)
        {
            _sceneName = sceneName;
            _assetModule = assetModule;
            Init();
        }

        private void Init()
        {
            _abAsync = _assetModule.LoadSceneBundleAsync(_sceneName);
            _abAsync.On((async) =>
            {
                if (async.IsCompleted)
                {
                    _async = SceneManager.LoadSceneAsync(_sceneName, LoadSceneMode.Additive);
                    _async.completed += (a) =>
                    {
                        bool isFind = false;
                        var objects = SceneManager.GetSceneByName(_sceneName).GetRootGameObjects();
                        foreach (var item in objects)
                        {
                            var result = item.GetComponent<T>();
                            if (result != null)
                            {
                                Result = result;
                                isFind = true;
                                break;
                            }
                        }
                        if (!isFind) throw new NullReferenceException($"未发现该对象:{typeof(T)},请检查场景资源文件:{_sceneName}");
                        Completed();
                    };
                }
            });
        }
    }
}