using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;

public class AsyncLoad
{
    /// <summary>
    /// 场景名称
    /// </summary>
    private string sceneName;
    /// <summary>
    /// 加载完成后自动进入
    /// </summary>
    private bool boolAutomaticEnter;
    /// <summary>
    /// 加载进度
    /// </summary>
    private int loadProgress;
    /// <summary>
    /// 异步操作
    /// </summary>
    private AsyncOperation asyncOperation;

    /// <summary>
    /// 加载进度
    /// </summary>
    public int load_progress { get => loadProgress; }
    public AsyncOperation AsyncOperation { get => asyncOperation; }

    public AsyncLoad()
    {

    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="_sceneName">场景名称</param>
    /// <param name="_automaticEnter">加载完成后是否自动进入</param>
    public AsyncLoad(string _sceneName, bool _automaticEnter)
    {
        sceneName = _sceneName;
        boolAutomaticEnter = _automaticEnter;
    }

    /// <summary>
    /// 异步加载场景
    /// </summary>
    /// <param name="SceneName"></param>
    /// <returns></returns>
    public IEnumerator AsyncLoadScene(string _scene_name, bool _auto_enter_scene, LoadSceneMode _load_scene_mode = LoadSceneMode.Single)
    {
        var _scene = SceneManager.GetSceneByName(_scene_name);
        if (_scene == null || _scene.isLoaded)
        {
            yield break;
        }
        yield return new WaitForSeconds(0.1f);
        int displayProgress = 0;
        if (!string.IsNullOrEmpty(_scene_name))
        {
            asyncOperation = SceneManager.LoadSceneAsync(_scene_name, _load_scene_mode);
            asyncOperation.allowSceneActivation = false;

            while (!asyncOperation.isDone)
            {
                int toProgress = (int)asyncOperation.progress * 100;
                while (displayProgress < toProgress)
                {
                    ++displayProgress;
                    loadProgress = displayProgress;
                    Debug.Log(load_progress);
                    yield return new WaitForEndOfFrame();
                }
                toProgress = 100;
                while (displayProgress < toProgress)
                {
                    ++displayProgress;
                    loadProgress = displayProgress;
                    Debug.Log(load_progress);
                    yield return new WaitForEndOfFrame();
                }

                if (asyncOperation.progress >= 0.89f)
                {
                    if (_auto_enter_scene) asyncOperation.allowSceneActivation = true;
                }
                yield return null;
            }
        }
    }

    /// <summary>
    /// 异步卸载场景
    /// </summary>
    /// <param name="_scene_name"></param>
    /// <returns></returns>
    public IEnumerator AsyncUnloadScene(string _scene_name)
    {
        var _scene = SceneManager.GetSceneByName(_scene_name);
        if (_scene == null || !_scene.isLoaded)
            yield break;
        yield return SceneManager.UnloadSceneAsync(_scene_name);
    }

    /// <summary>
    /// 进入场景
    /// </summary>
    public void EnterScene()
    {
        asyncOperation.allowSceneActivation = true;
    }
}