using System.Collections.Generic;
using System.Linq;
using UnityEditor;
using UnityEditor.SceneManagement;
using UnityEngine;
using UnityEngine.Rendering;
using UnityEngine.SceneManagement;
using Object = UnityEngine.Object;

public abstract class PostProcessor
{
    /// <summary>
    /// 后处理命名后缀
    /// </summary>
    public const string SCENE_POST_PROCESS_NAME = "PostProcess";

    /// <summary>
    /// 合并网格后的节点
    /// </summary>
    private const string SCENE_COMBINED_NAME = "Combined";

    /// <summary>
    /// 后处理后存放地面贴图材质的文件夹命名
    /// </summary>
    private const string GROUND_TEXTURE_MAT_PATH = "Ground";

    /// <summary>
    /// 后处理后存放光照贴图和烘焙数据的文件夹命名
    /// </summary>
    private const string LIGHT_BAKE_NAME = "LightMaps";

    /// <summary>
    /// 后处理预制体根路径
    /// </summary>
    protected const string PREFAB_POSTPROCESS_DIR = "Assets/Art_Out/AutoGen/PostProcessPrefabs";

    /// <summary>
    /// 场景资源分组路径 暂时舍弃没有使用Addressable
    /// </summary>
    protected const string SCENE_ADDRESSABLE_GROUP = "PostProcessScenes";

    /// <summary>
    /// 预制体资源分组路径 暂时舍弃没有使用Addressable
    /// </summary>
    protected const string PREFAB_ADDRESSABLE_GROUP = "PostProcessPrefabs";

    /// <summary>
    /// 区分剧情场景的文件夹前缀
    /// </summary>
    private const string STORY_SCENE_PREFIX = "story_";

    /// <summary>
    /// 切割地面贴图宽度
    /// </summary>
    private const int GROUND_SPLIT_WIDTH = 1024;

    /// <summary>
    /// 切割地面贴图高度
    /// </summary>
    private const int GROUND_SPLIT_HEIGHT = 1024;

    /// <summary>
    /// 像素
    /// </summary>
    private const int UPP = 100;

    /// <summary>
    /// 烘焙后需要替换shader的渲染器列表
    /// </summary>
    private readonly List<Renderer> needReplaceRenderers = new();

    /// <summary>
    /// 烘焙后需要关闭产生阴影的渲染器列表
    /// </summary>
    private readonly List<Renderer> allBakeRenderers = new();

    /// <summary>
    /// 实时灯光
    /// </summary>
    private readonly List<Light> realTimeLights = new();

    /// <summary>
    /// 烘焙灯光
    /// </summary>
    private readonly List<Light> bakedLights = new();

    /// <summary>
    /// 检查规范节点
    /// </summary>
    private readonly List<string> sceneRoots = new()
    {
        "Main Camera", "TerrainGridSystem", "Art", "SceneManager", "MapEditor", "LevelEditor", "TGSPreview",
        "InputManager (Singleton)"
    };

    /// <summary>
    /// 需要替换shader烘焙的节点
    /// </summary>
    private readonly List<string> bakeReplaceShaderRoot = new() { "CombinedRoot" };

    /// <summary>
    /// 需要烘焙的其他地面节点
    /// </summary>
    private readonly List<string> groundRoot = new() { "Ground_2" };

    /// <summary>
    /// 后处理文件夹路径 
    /// </summary>
    protected string ProcessedResourceDir => $"{ResourcesBaseDir}/{PostProcessFolderName}";

    protected abstract string PostProcessFolderName { get; }

    protected abstract string ResourcesBaseDir { get; }

    protected abstract Object AssetToPostProcess { get; }

    protected abstract string OutputAssetPath { get; }

    private string LightBakeDir => $"{ProcessedResourceDir}/{LIGHT_BAKE_NAME}";

    private string GroundSplitDir => $"{ProcessedResourceDir}/{GROUND_TEXTURE_MAT_PATH}";

    /// <summary>
    /// 是否完成复制场景
    /// </summary>
    private bool HasClone { get; set; }

    /// <summary>
    /// 原始场景路径
    /// </summary>
    private string OriginAssetPath => AssetDatabase.GetAssetPath(AssetToPostProcess);

    protected PostProcessInstructor _processInstructor;

    private PostProcessInstructor _clonedProcessInstructor;

    private PostProcessInstructor PostProcessInstructor => HasClone ? _clonedProcessInstructor : _processInstructor;

    /// <summary>
    /// 用于处理后处理场景中的预制体
    /// </summary>
    private Transform _unpackedCombinedObjectsRoot;

    private Transform CombinedObjectsRoot
    {
        get
        {
            if (_unpackedCombinedObjectsRoot != null && HasClone)
                return _unpackedCombinedObjectsRoot;

            if (PostProcessInstructor == null || PostProcessInstructor.combinedObjectsRoot == null)
            {
                Debug.LogError("找不到Art节点!");
                return PostProcessInstructor.transform.parent;
            }

            return PostProcessInstructor.combinedObjectsRoot;
        }
    }

    protected abstract PostProcessInstructor Clone();

    protected abstract void AfterAll(bool destroyAfterPostProcess);

    protected virtual void Init(PostProcessInstructor postProcessInstructor)
    {
        _processInstructor = postProcessInstructor;
    }

    public static PostProcessInstructor FindInstructorInScene(Scene scene)
    {
        var instructors = Object.FindObjectsOfType<PostProcessInstructor>();
        return instructors.FirstOrDefault(pi => pi.gameObject.scene == scene);
    }

    #region 后处理多节点

    /// <summary>
    /// 后处理多节点场景 不烘焙 预制体不解包
    /// </summary>
    /// <param name="postProcessInstructors"></param>
    /// <param name="destroyAfterPostProcess"></param>
    public void PostProcessMore(PostProcessInstructor[] postProcessInstructors, bool destroyAfterPostProcess = false)
    {
        if (postProcessInstructors.Length <= 0)
            return;

        var firstPostProcessInstructor = postProcessInstructors[0];
        if (!CheckPostProcessInstructor(firstPostProcessInstructor))
            return;

        Init(firstPostProcessInstructor);
        HasClone = false;
        EditorSceneManager.SaveOpenScenes();

        // 创建文件夹
        AssetDatabase.DeleteAsset(ProcessedResourceDir);
        AssetDatabase.CreateFolder(ResourcesBaseDir, PostProcessFolderName);
        AssetDatabase.CreateFolder(ProcessedResourceDir, GROUND_TEXTURE_MAT_PATH);

        // 复制场景为后处理场景
        Clone();

        // 在后处理场景中重新获取 PostProcessInstructor 组
        var newPostProcessInstructors = Object.FindObjectsOfType<PostProcessInstructor>();
        var index = 0;
        foreach (var postProcessInstructor in newPostProcessInstructors)
        {
            // DebugUtil.LogError($"重新获取的postProcessInstructor属于场景：{postProcessInstructor.gameObject.scene.name}");
            _processInstructor = postProcessInstructor;

            if (PostProcessInstructor == null)
            {
                // DebugUtil.LogError($"PostProcessInstructor为空，克隆参数：{HasClone}");
                continue;
            }

            var outputPath = SCENE_COMBINED_NAME + index++;
            BakeCombinedGameObject(outputPath);

            if (!PostProcessInstructor.enableSplitGround)
            {
                // 关闭切割地面 给地面添加BoxCollider
                GroundAddBoxCollider();
                ChangeMapTextureAndMatPath();
            }
            else
            {
                SplitGroundTexture();
            }

            SetFogPosition();
            RemoveRedundant();
            HideCamera();
            DestroyUselessObject();
        }

        AfterAll(destroyAfterPostProcess);
        PostProcessData.EditorInstance.AddPostProcessData(AssetToPostProcess, OutputAssetPath);
        Debug.Log($"执行后处理成功，后处理资源源路径:{OriginAssetPath} 后处理后路径:{OutputAssetPath}");
        AssetDatabase.SaveAssets();
        AssetDatabase.Refresh();
    }

    #endregion

    #region 普通后处理

    /// <summary>
    /// 后处理
    /// </summary>
    /// <param name="postProcessInstructor"></param>
    /// <param name="destroyAfterPostProcess"></param>
    /// <param name="defaultCameraParam">是否为默认相机</param>
    public void PostProcess(PostProcessInstructor postProcessInstructor, bool destroyAfterPostProcess = false,
        bool defaultCameraParam = true)
    {
        if (!CheckPostProcessInstructor(postProcessInstructor))
            return;

        Init(postProcessInstructor);
        HasClone = false;
        EditorSceneManager.SaveOpenScenes();
        PrepareFolders();

        // 复制 ProcessInstructor 组件
        _clonedProcessInstructor = Clone();
        HasClone = true;
        if (_clonedProcessInstructor == null)
        {
            Debug.LogError("_clonedProcessInstructor is null!");
            return;
        }

        var combineRootObj = BakeCombinedGameObject();

        _PrepareForBake(combineRootObj.transform);

        // 如果Art为预制体先进行解包
        UnpackPostSceneArt();

        if (!PostProcessInstructor.enableSplitGround)
        {
            // 关闭切割地面 给地面添加BoxCollider
            GroundAddBoxCollider();
            ChangeMapTextureAndMatPath();
        }
        else
        {
            SplitGroundTexture();
        }

        BakeLightmaps();

        SetFogPosition();
        if (!defaultCameraParam)
        {
            SetCameraParam();
        }

        UnpackPostSceneArt();
        RemoveRedundant();
        HideCamera();

        DestroyUselessObject();
        AfterAll(destroyAfterPostProcess);


        PostProcessData.EditorInstance.AddPostProcessData(AssetToPostProcess, OutputAssetPath);
        Debug.Log($"执行后处理成功，后处理资源源路径:{OriginAssetPath} 后处理后路径:{OutputAssetPath}");
        AssetDatabase.SaveAssets();
        AssetDatabase.Refresh();
    }

    #endregion

    private void _PrepareForBake(Transform combineRootParent)
    {
        if (PostProcessInstructor == null || !PostProcessInstructor.enableLightmapBaking)
            return;

        for (var i = 0; i < combineRootParent.childCount; ++i)
        {
            var child = combineRootParent.GetChild(i);
            if (child == null)
                continue;
            var meshRenderer = child.GetComponent<MeshRenderer>();
            if (meshRenderer == null)
            {
                continue;
            }

            if (meshRenderer.shadowCastingMode == ShadowCastingMode.On)
            {
                meshRenderer.shadowCastingMode = ShadowCastingMode.On;
                meshRenderer.staticShadowCaster = true;
                meshRenderer.material.doubleSidedGI = true;
            }
        }
    }

    private bool CheckPostProcessInstructor(PostProcessInstructor postProcessInstructor)
    {
        if (postProcessInstructor == null)
        {
            Debug.LogError("postProcessInstructor is null");
            return false;
        }

        if (postProcessInstructor.processPrefab &&
            (!PrefabUtility.IsPartOfAnyPrefab(postProcessInstructor) ||
             EditorUtility.IsPersistent(postProcessInstructor)))
        {
            Debug.LogError("postProcessInstructor不在任何预制体内或者其不是预制体实例");
            return false;
        }

        var currentScene = postProcessInstructor.gameObject.scene;
        var objs = currentScene.GetRootGameObjects();
        foreach (var obj in objs)
        {
            if (!sceneRoots.Contains(obj.name))
            {
                Debug.LogWarning($"{currentScene.name} 场景有其他节点:{obj.name}，请检查节点规范");
            }
        }

        return true;
    }

    private void PrepareFolders()
    {
        AssetDatabase.DeleteAsset(ProcessedResourceDir);
        AssetDatabase.CreateFolder(ResourcesBaseDir, PostProcessFolderName);
        AssetDatabase.CreateFolder(ProcessedResourceDir, SCENE_COMBINED_NAME);
        AssetDatabase.CreateFolder(ProcessedResourceDir, GROUND_TEXTURE_MAT_PATH);
    }

    /// <summary>
    /// 合并网格、贴图
    /// </summary>
    private GameObject BakeCombinedGameObject(string combinedName = "")
    {
        var art = CombinedObjectsRoot;
        var combinedRootName = string.IsNullOrEmpty(combinedName) ? SCENE_COMBINED_NAME : combinedName;
        var outputPath = $"{ProcessedResourceDir}/{combinedRootName}";

        // 收集渲染器
        var renderers = MeshCombineUtils.CollectRenderers(PostProcessInstructor.rootsToCombine);
        Debug.Log($"合批前收集到 {renderers.Count} 个渲染器");

        var prefix = GetScenePrefix();
        var combinedRoot = new GameObject("CombinedRoot");
        combinedRoot.transform.parent = art.transform;
        DebugUtil.Log($"合并节点是:{GameObjectUtils.GetFullPath(combinedRoot)},输出路径：{outputPath}，" +
                      $"单位贴图尺寸:{(int)PostProcessInstructor.postProcessTextureUnitSize}");
        try
        {
            if (PostProcessInstructor.enableBatchGrouping)
            {
                // 按照距离对渲染器进行分组
                Dictionary<string, List<Renderer>> rendererGroups =
                    MeshCombineUtils.GroupRenderersByProximity(renderers, PostProcessInstructor.batchGroupDistance);
                SceneCombineUtil.Instance.CombineGameObjectsByGroups(rendererGroups, combinedRoot.transform,
                    outputPath,
                    (int)PostProcessInstructor.postProcessTextureUnitSize,
                    PostProcessInstructor.sampleMaterials, prefix);
            }
            else
            {
                // 使用原有的合批方式
                SceneCombineUtil.Instance.CombineGameObjects(renderers, combinedRoot.transform, outputPath,
                    (int)PostProcessInstructor.postProcessTextureUnitSize,
                    PostProcessInstructor.sampleMaterials, prefix);
            }

            // 如果是剧情场景，重命名生成的所有物体添加前缀
            if (!string.IsNullOrEmpty(prefix))
            {
                var combined = combinedRoot.GetComponentsInChildren<Transform>();
                foreach (var trans in combined)
                {
                    if (trans != combinedRoot.transform && !trans.name.StartsWith(prefix))
                    {
                        trans.name = prefix + trans.name;
                    }
                }
            }

            foreach (var root in PostProcessInstructor.rootsToCombine)
            {
                if (!root)
                {
                    continue;
                }

                Object.DestroyImmediate(root.gameObject);
            }
        }
        catch (System.Exception ex)
        {
            Debug.LogError($"合批过程中发生错误: {ex.Message}\n{ex.StackTrace}");
            // 如果合批失败，保留原始物体
            if (combinedRoot != null)
            {
                Object.DestroyImmediate(combinedRoot);
            }
        }

        return combinedRoot;
    }

    #region 地面处理

    /// <summary>
    /// 修改地面贴图及材质的路径 用于打包
    /// </summary>
    private void ChangeMapTextureAndMatPath()
    {
        var ground = PostProcessInstructor.ground;
        if (_unpackedCombinedObjectsRoot != null && HasClone)
        {
            ground = _unpackedCombinedObjectsRoot.Find("Ground")?.gameObject;
        }

        GroundUtils.ChangeMapTextureAndMatPath(ground, GroundSplitDir, GetScenePrefix(),
            groundRoot, CombinedObjectsRoot, _unpackedCombinedObjectsRoot);
    }

    /// <summary>
    /// 给地面添加BoxCollider
    /// </summary>
    private void GroundAddBoxCollider()
    {
        var ground = PostProcessInstructor.ground;
        if (_unpackedCombinedObjectsRoot != null && HasClone)
        {
            ground = _unpackedCombinedObjectsRoot.Find("Ground")?.gameObject;
        }

        if (ground != null)
        {
            // DebugUtil.LogError("获取的地面节点全路径：" + GameObjectUtils.GetFullPath(ground));
            SceneUtils.AddBoxColliderToGround(ground);
        }
        else
        {
            Debug.LogError("场景地面节点不存在，无法添加BoxCollider");
        }

        // 移除下层地面的碰撞体
        var ground_2 = GameObject.Find("Ground_2");
        if (ground_2 != null)
        {
            var collider = ground_2.GetComponent<Collider>();
            if (collider != null)
            {
                Object.DestroyImmediate(collider);
            }
        }
    }

    /// <summary>
    /// 切割地面
    /// </summary>
    private void SplitGroundTexture()
    {
        var ground = PostProcessInstructor.ground;
        if (ground == null)
            return;

        GroundUtils.SplitGroundTexture(ground, GroundSplitDir, GetScenePrefix(), GROUND_SPLIT_WIDTH,
            GROUND_SPLIT_HEIGHT);
    }

    #endregion

    /// <summary>
    /// 设置雾的位置
    /// </summary>
    private void SetFogPosition()
    {
        SceneUtils.SetFogPosition(PostProcessInstructor.fog);
    }

    /// <summary>
    /// 销毁多余eventSystems
    /// </summary>
    private void RemoveRedundant()
    {
        SceneUtils.RemoveRedundantEventSystems(PostProcessInstructor.gameObject.scene);
    }

    private void DestroyUselessObject()
    {
        foreach (var root in PostProcessInstructor.rootsToCombine)
        {
            if (!root)
            {
                continue;
            }

            Object.DestroyImmediate(root.gameObject, true);
        }

        Object.DestroyImmediate(PostProcessInstructor.gameObject, true);

        var designerObj = GameObject.Find("Designer");
        if (designerObj != null)
        {
            Object.DestroyImmediate(designerObj, true);
        }
    }

    /// <summary>
    /// 检测是否为剧情场景
    /// </summary>
    /// <returns></returns>
    private bool IsStoryScene()
    {
        var sceneName = PostProcessInstructor.gameObject.scene.name;
        return sceneName.Contains(STORY_SCENE_PREFIX);
    }

    private string GetScenePrefix()
    {
        return IsStoryScene() ? STORY_SCENE_PREFIX : "";
    }

    #region 保存相机参数

    private void SetCameraParam()
    {
        var postScene = PostProcessInstructor.gameObject.scene;
        var scene = _processInstructor.gameObject.scene;

        foreach (var rootObj in scene.GetRootGameObjects())
        {
            if (rootObj.CompareTag("MainCamera"))
            {
                CloneCameraToScene(rootObj, postScene);
                break;
            }
        }
    }

    private void CloneCameraToScene(GameObject obj, Scene scene)
    {
        // 只更改transform
        var oldPosition = obj.transform.position;
        var oldRotation = obj.transform.rotation;
        GameObject oldCamera = null;
        foreach (var rootObj in scene.GetRootGameObjects())
        {
            if (rootObj.CompareTag("MainCamera"))
            {
                oldCamera = rootObj;
                break;
            }
        }

        if (oldCamera == null) return;
        oldCamera.transform.position = oldPosition;
        oldCamera.transform.rotation = oldRotation;
    }

    private void HideCamera()
    {
        var scene = PostProcessInstructor.gameObject.scene;
        var cameras = Object.FindObjectsOfType<Camera>();

        foreach (var camera in cameras)
        {
            if (camera.gameObject.scene == scene)
            {
                camera.gameObject.SetActive(false);
                // Debug.Log($"已隐藏相机: {camera.gameObject.name}");
            }
        }

        EditorSceneManager.MarkSceneDirty(SceneManager.GetActiveScene());
        EditorSceneManager.SaveOpenScenes();
    }

    #endregion

    #region 烘焙

    /// <summary>
    /// 烘焙灯光贴图的方法
    /// </summary>
    private void BakeLightmaps()
    {
        // 检查是否开启了烘焙选项
        if (PostProcessInstructor == null || !PostProcessInstructor.enableLightmapBaking)
            return;

        Debug.Log("开始灯光烘焙过程...");

        // 1. 从CombinedObjectsRoot下查找灯光 改为烘焙灯光
        LightmapUtils.PrepareLight(CombinedObjectsRoot, realTimeLights, bakedLights);

        // 2. 处理参与烘焙的节点
        LightmapUtils.PreProcessBake(bakeReplaceShaderRoot, CombinedObjectsRoot, true, true, allBakeRenderers,
            needReplaceRenderers);
        LightmapUtils.PreProcessBake(groundRoot, CombinedObjectsRoot, false, false, allBakeRenderers,
            needReplaceRenderers);
        ProcessGround(3000);

        Debug.Log($"总共收集到 {needReplaceRenderers.Count} 个渲染器需要替换shader");
        Debug.Log($"总共收集到 {allBakeRenderers.Count} 个渲染器参与烘焙");

        // 3.替换Shader为支持光照贴图的Shader
        MaterialUtils.ReplaceShaderWithLightmapShader(needReplaceRenderers);

        // 4. 开始烘焙
        LightmapUtils.Bake(SceneManager.GetActiveScene());

        // 5. 关闭所有烘焙物体的阴影投射
        foreach (var renderer in allBakeRenderers)
        {
            if (renderer != null)
                renderer.shadowCastingMode = ShadowCastingMode.Off;
        }

        // 6. 打开实时灯光
        LightmapUtils.RevertLight(realTimeLights, bakedLights);

        // 7.还原地面RenderQueue
        ProcessGround(2000);

        // 8. 复制光照烘焙文件到目标路径
        LightmapUtils.CopyLightmapFiles(SceneManager.GetActiveScene(), LightBakeDir);

        // 9. 保存场景
        EditorSceneManager.MarkSceneDirty(SceneManager.GetActiveScene());
        EditorSceneManager.SaveOpenScenes();

        Debug.Log("灯光烘焙处理完成");
    }

    private void ProcessGround(int renderQueue)
    {
        if (PostProcessInstructor.ground != null)
        {
            SceneUtils.SetGroundRenderQueue(PostProcessInstructor.ground, renderQueue);
        }
    }

    private void UnpackPostSceneArt()
    {
        if (CombinedObjectsRoot != null && PrefabUtility.IsPartOfPrefabInstance(CombinedObjectsRoot.gameObject))
        {
            // 保存对象的引用
            _unpackedCombinedObjectsRoot = CombinedObjectsRoot;
            SceneUtils.UnpackPrefab(CombinedObjectsRoot.gameObject);
        }
    }

    #endregion
}