using System.Collections;
using System.Collections.Generic;
using Cysharp.Threading.Tasks;
using Gameplay;
using Gameplay.SubSystems;
using PhxhSDK;
using UnityEngine;
using UnityEngine.SceneManagement;

/// <summary>
/// 游戏场景的通用业务逻辑
/// </summary>
public class GameSceneHelper : Singlenton<GameSceneHelper>
{
    public enum EnumScene
    {
        GameStart, // 登录场景
        GameMain, // 主场景
        GameLevel // 关卡（战场）场景
    }

    public const string SCENE_PREFIX = "Assets/Scenes/";
    public const string START_SCENE_NAME = "StartScene";
    public const string LEVEL_SCENE_NAME = "LevelScene";
    public const string MAIN_SCENE_NAME = "MainScene";
    public const string SCENE_SUFFIX = ".unity";

    private Dictionary<string, bool> _uiViewSceneDic = new();

    public async UniTask<LoadingResult> ChangeScene(EnumScene enumScene)
    {
        string sceneName = SCENE_PREFIX;
        switch (enumScene)
        {
            case EnumScene.GameStart:
                sceneName += START_SCENE_NAME;
                break;
            case EnumScene.GameMain:
                sceneName += MAIN_SCENE_NAME;
                break;
            case EnumScene.GameLevel:
                sceneName += LEVEL_SCENE_NAME;
                break;
            default:
                DebugUtil.LogError("{0}.ChangeScene, {1} has no scene name matched", GetType(), enumScene);
                sceneName += START_SCENE_NAME;
                break;
        }

        sceneName += SCENE_SUFFIX;
        await GameSceneManager.Instance.LoadSceneAsync(sceneName);

        return LoadingResult.Success;
    }

    /// <summary>
    /// 打开UI预览场景，当某个UI需要单独渲染场景时使用(如PVP布阵，营地等)
    /// 此时场景中的相机会只渲染UI场景内的物件
    /// </summary>
    /// <param name="scenePath"></param>
    /// <param name="mode"></param>
    /// <param name="switchMainCamera">打开场景后是否自动切换主相机</param>
    /// <returns></returns>
    public async UniTask<GameSceneManager.SceneHandle> LoadSceneForUIView(string scenePath,
        LoadSceneMode mode = LoadSceneMode.Single, bool switchMainCamera = true)
    {
        var sceneHandle = await GameSceneManager.Instance.LoadSceneAsync(scenePath, mode);
        if (sceneHandle == null)
        {
            return null;
        }

        var scene = sceneHandle.Scene;
        var groundLayer = LayerMask.NameToLayer("Ground");
        var UIViewLayer = LayerMask.NameToLayer("UIView");
        var UIViewMask = LayerMask.GetMask("UIView", "Ground");
        //调整所有物品的层级
        var roots = scene.GetRootGameObjects();
        foreach (var root in roots)
        {
            //将所有gameObject设置为UIView层
            root.SetLayerEx(UIViewLayer, groundLayer);
        }

        //设置相机的culling mask
        foreach (var root in roots)
        {
            var cam = root.GetComponent<Camera>();
            if (!cam)
                continue;
            cam.cullingMask = UIViewMask;
        }

        //设置光源culling mask
        var lights = Object.FindObjectsOfType<Light>();
        foreach (var light in lights)
        {
            if (light.gameObject.scene != scene)
                continue;
            light.cullingMask = UIViewMask;
        }

        //切换全局GI
        SceneManager.SetActiveScene(scene);
        if (switchMainCamera)
        {
            var sceneMainCamera = sceneHandle.SceneMainCamera;
            CameraManager.Instance.SwitchMainCamera(sceneMainCamera);
        }

        _uiViewSceneDic.Add(scenePath, switchMainCamera);
        return sceneHandle;
    }

    public async UniTask UnLoadSceneForUIView(string scenePath)
    {
        if (!_uiViewSceneDic.TryGetValue(scenePath, out var switchMainCamera))
        {
            DebugUtil.LogError($"没有加载过场景！scenePath:{scenePath}");
            return;
        }

        await GameSceneManager.Instance.UnLoadSceneAsync(scenePath);
        if (switchMainCamera)
        {
            CameraManager.Instance.RevertMainCamera();
        }

        _uiViewSceneDic.Remove(scenePath);
    }
}