/*
 * MonsterVATBatchBaker
 *
 * 一键怪物 VAT 烘焙工具:
 *   输入 — Assets/_External/Monsters/<name>/<name>.FBX 主 FBX(必须 Legacy animationType=1)
 *   流程 —
 *     1) 临时场景中实例化主 FBX
 *     2) 给 root 加 Animation 组件
 *     3) 从同目录的 <name>@Run.FBX 拿 Legacy Run AnimationClip,AddClip 到 Animation
 *     4) 反射调用 SelectiveVATBakerWindow.BakeAll(自动 X=-90 if Z-up)
 *     5) 销毁场景实例
 *   输出 — Assets/_VAT_Baking/Output/<name>/<name>_VAT.prefab + Atlas + Database
 *
 * 用法:
 *   - Project 窗口里选中一个或多个主 FBX(必须在 _External/Monsters 或 _External/Bosses 下),
 *     菜单 "Tools/OctoberStudio/VAT/Bake Selected Monsters (Run-only)" 即可。
 *   - 或者直接选中 _External/Monsters 文件夹批量处理。
 */

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
using UnityEditor;
using UnityEngine;

namespace OctoberStudio.EditorTools
{
    public static class MonsterVATBatchBaker
    {
        private const string OutputRoot = "Assets/_VAT_Baking/Output";
        private static readonly string[] AnimNameCandidates = { "Run", "run", "RUN" };

        // 测试入口: 直接烤 mon1001 (用 Resources/Role/Monster 下已配置的 .prefab)
        [MenuItem("Tools/OctoberStudio/VAT/Bake mon1001 (Test Sample)", priority = 59)]
        public static void BakeMon1001Sample()
        {
            BakePrefab("Assets/Resources/Role/Monster/mon1001.prefab");
        }

        private const string MonsterPrefabsDir = "Assets/Resources/Role/Monster";

        // 批量烤 Resources/Role/Monster/*.prefab 全部小怪 (使用配好 Animation + SMR 的 prefab,
        // 不需要外挂 @Run.FBX 文件查找)
        [MenuItem("Tools/OctoberStudio/VAT/Bake ALL Monsters in Resources", priority = 58)]
        public static void BakeAllResourcesMonsters()
        {
            if (!AssetDatabase.IsValidFolder(MonsterPrefabsDir))
            {
                Debug.LogError($"[BatchBake] 目录不存在: {MonsterPrefabsDir}");
                return;
            }

            // 找该目录下所有 .prefab(不递归子目录,直接 1 层)
            var guids = AssetDatabase.FindAssets("t:Prefab", new[] { MonsterPrefabsDir });
            var paths = new List<string>();
            foreach (var g in guids)
            {
                var p = AssetDatabase.GUIDToAssetPath(g);
                // 限定在该目录下 (FindAssets 默认是递归,这里再过滤一道)
                if (p.StartsWith(MonsterPrefabsDir + "/") &&
                    Path.GetDirectoryName(p)?.Replace("\\", "/") == MonsterPrefabsDir)
                {
                    paths.Add(p);
                }
            }
            paths.Sort();

            if (paths.Count == 0)
            {
                Debug.LogWarning($"[BatchBake] {MonsterPrefabsDir} 下没找到 prefab");
                return;
            }

            Debug.Log($"[BatchBake] 共 {paths.Count} 只小怪开始烤: " + string.Join(", ", paths.Select(Path.GetFileNameWithoutExtension)));

            int ok = 0, skip = 0, fail = 0;
            var failList = new List<string>();
            for (int i = 0; i < paths.Count; i++)
            {
                var name = Path.GetFileNameWithoutExtension(paths[i]);
                if (EditorUtility.DisplayCancelableProgressBar(
                        "Bake ALL Monsters", $"[{i + 1}/{paths.Count}] {name}",
                        (float)i / paths.Count))
                {
                    Debug.LogWarning("[BatchBake] 用户取消");
                    break;
                }

                // 已烤过(目录存在)就跳过,避免覆盖手工调整的 prefab。强制重烤请删 OutputDir/<name>
                var outPath = $"{OutputRoot}/{name}";
                if (AssetDatabase.IsValidFolder(outPath))
                {
                    Debug.Log($"[BatchBake] 跳过(已存在): {outPath}");
                    skip++;
                    continue;
                }

                try
                {
                    BakePrefab(paths[i]);
                    ok++;
                }
                catch (Exception e)
                {
                    Debug.LogError($"[BatchBake] 失败 {name}: {e.Message}");
                    fail++;
                    failList.Add($"{name}: {e.Message}");
                }
            }
            EditorUtility.ClearProgressBar();
            AssetDatabase.SaveAssets();
            AssetDatabase.Refresh();

            Debug.Log($"[BatchBake] Done — OK={ok}, Skip={skip}, Fail={fail}");
            if (failList.Count > 0)
                Debug.LogWarning("[BatchBake] 失败列表:\n" + string.Join("\n", failList));
        }

        // 给后续批量烤怪用 — 直接用已配置 prefab,不需要外挂 Animation 组件
        public static void BakePrefab(string prefabPath)
        {
            try
            {
                var prefab = AssetDatabase.LoadAssetAtPath<GameObject>(prefabPath);
                if (prefab == null) { Debug.LogError($"[BakePrefab] 找不到: {prefabPath}"); return; }

                var instance = (GameObject)PrefabUtility.InstantiatePrefab(prefab);
                if (instance == null) { Debug.LogError("[BakePrefab] Instantiate failed"); return; }
                try
                {
                    // 关 Animator(如果存在),避免和 Animation 双源冲突
                    var animator = instance.GetComponentInChildren<Animator>();
                    if (animator != null) animator.enabled = false;

                    var anim = instance.GetComponent<Animation>();
                    if (anim == null)
                    {
                        // root 没 Animation 时,从子节点提
                        anim = instance.GetComponentInChildren<Animation>();
                        if (anim == null) { Debug.LogError("[BakePrefab] 没找到 Animation 组件"); return; }
                    }

                    var smr = instance.GetComponentInChildren<SkinnedMeshRenderer>();
                    if (smr == null) { Debug.LogError("[BakePrefab] 没找到 SkinnedMeshRenderer"); return; }

                    Debug.Log($"[BakePrefab] {Path.GetFileNameWithoutExtension(prefabPath)}: mesh={smr.sharedMesh?.name} verts={smr.sharedMesh?.vertexCount}");

                    // 如果 Animation 在子节点上,我们需要把它搬到 root 才能让 baker 用
                    // 但 baker 用 _target.GetComponent<Animation>(),所以 root 必须有 Animation
                    if (instance.GetComponent<Animation>() == null && anim != null)
                    {
                        // 把子节点 Animation 引用的 clip 抽出来,在 root 加 Animation 组件
                        var newAnim = instance.AddComponent<Animation>();
                        foreach (AnimationState st in anim) newAnim.AddClip(st.clip, st.clip.name);
                        var firstClip = anim.clip;
                        if (firstClip != null) newAnim.clip = firstClip;
                    }

                    BakeViaSelectiveBaker(instance);
                }
                finally
                {
                    UnityEngine.Object.DestroyImmediate(instance);
                }
                AssetDatabase.SaveAssets();
                AssetDatabase.Refresh();
            }
            catch (Exception e)
            {
                Debug.LogError($"[BakePrefab] Exception: {e}");
            }
        }

        [MenuItem("Tools/OctoberStudio/VAT/Bake Selected Monsters (Run-only)", priority = 60)]
        public static void BakeSelected()
        {
            BakeFromPaths(CollectFbxFromSelection().ToArray());
        }

        private static void BakeFromPaths(string[] paths)
        {
            var fbxList = paths != null ? paths.ToList() : new List<string>();
            if (fbxList.Count == 0)
            {
                Debug.LogWarning("[BakeMonsters] 没有 FBX 路径输入。");
                return;
            }

            int ok = 0, fail = 0;
            var failList = new List<string>();
            for (int i = 0; i < fbxList.Count; i++)
            {
                var path = fbxList[i];
                if (EditorUtility.DisplayCancelableProgressBar(
                        "Bake Monsters", $"[{i + 1}/{fbxList.Count}] {Path.GetFileName(path)}",
                        (float)i / fbxList.Count))
                {
                    Debug.LogWarning("[BakeMonsters] User cancelled.");
                    break;
                }

                try
                {
                    BakeOne(path);
                    ok++;
                }
                catch (Exception e)
                {
                    Debug.LogError($"[BakeMonsters] Failed: {path}\n{e}");
                    fail++;
                    failList.Add($"{Path.GetFileNameWithoutExtension(path)}: {e.Message}");
                }
            }
            EditorUtility.ClearProgressBar();
            AssetDatabase.SaveAssets();
            AssetDatabase.Refresh();

            Debug.Log($"[BakeMonsters] Done. OK={ok}, Fail={fail}");
            if (failList.Count > 0)
                Debug.LogWarning("[BakeMonsters] 失败列表:\n" + string.Join("\n", failList));
        }

        private static List<string> CollectFbxFromSelection()
        {
            var paths = new List<string>();
            foreach (var obj in Selection.objects)
            {
                var p = AssetDatabase.GetAssetPath(obj);
                if (string.IsNullOrEmpty(p)) continue;

                if (Directory.Exists(p))
                {
                    // 文件夹: 递归找主 FBX (不含 @)
                    var allFbx = AssetDatabase.FindAssets("t:Model", new[] { p });
                    foreach (var g in allFbx)
                    {
                        var path = AssetDatabase.GUIDToAssetPath(g);
                        var name = Path.GetFileName(path);
                        if (!name.Contains("@") && !paths.Contains(path)) paths.Add(path);
                    }
                }
                else if (p.EndsWith(".fbx", StringComparison.OrdinalIgnoreCase) ||
                         p.EndsWith(".FBX", StringComparison.OrdinalIgnoreCase))
                {
                    var name = Path.GetFileName(p);
                    if (!name.Contains("@") && !paths.Contains(p)) paths.Add(p);
                }
            }
            return paths;
        }

        private static void BakeOne(string fbxAssetPath)
        {
            // 1) 加载主 FBX
            var fbx = AssetDatabase.LoadAssetAtPath<GameObject>(fbxAssetPath);
            if (fbx == null) throw new Exception("FBX not loaded: " + fbxAssetPath);

            // 2) 找同目录的 @Run.FBX 中的 Run clip
            var runClip = FindRunClip(fbxAssetPath);
            if (runClip == null)
                throw new Exception("找不到 Run AnimationClip。请确保同目录有 <name>@Run.FBX 且其中含 Legacy Run clip");

            // 3) 实例化到临时隐藏 GameObject (不入场景层级,但 baker 需要 SMR + Animation)
            //    PrefabUtility.InstantiatePrefab 不能直接 hideFlags,但我们烤完立刻销毁,无所谓
            var instance = (GameObject)PrefabUtility.InstantiatePrefab(fbx);
            if (instance == null) throw new Exception("Instantiate failed: " + fbxAssetPath);

            try
            {
                // 4) 确保有 SkinnedMeshRenderer
                var smr = instance.GetComponentInChildren<SkinnedMeshRenderer>();
                if (smr == null) throw new Exception("FBX 内找不到 SkinnedMeshRenderer: " + fbxAssetPath);

                // 5) 加 Animation 组件 (主 FBX importAnimation=0 时根上没有 Animation)
                var anim = instance.GetComponent<Animation>();
                if (anim == null) anim = instance.AddComponent<Animation>();

                // 把 Run clip 加入,并设 default clip
                if (!runClip.legacy)
                    throw new Exception("Run clip 不是 Legacy。请在 @Run.FBX Inspector 的 Animation Type 设为 Legacy");

                anim.AddClip(runClip, "Run");
                anim.clip = runClip;
                anim.playAutomatically = false;

                Debug.Log($"[BakeOne] {Path.GetFileNameWithoutExtension(fbxAssetPath)}: mesh={smr.sharedMesh?.name} verts={smr.sharedMesh?.vertexCount}, clip={runClip.name} ({runClip.length:F2}s)");

                // 6) 反射触发 SelectiveVATBakerWindow.BakeAll
                BakeViaSelectiveBaker(instance);
            }
            finally
            {
                UnityEngine.Object.DestroyImmediate(instance);
            }
        }

        private static AnimationClip FindRunClip(string mainFbxPath)
        {
            var dir = Path.GetDirectoryName(mainFbxPath)?.Replace("\\", "/");
            var baseName = Path.GetFileNameWithoutExtension(mainFbxPath);
            if (string.IsNullOrEmpty(dir) || string.IsNullOrEmpty(baseName)) return null;

            // 候选: <name>@Run.FBX, <name>@run.FBX
            foreach (var suffix in AnimNameCandidates)
            {
                var p = $"{dir}/{baseName}@{suffix}.FBX";
                var clip = LoadFirstClipFromFbx(p);
                if (clip != null) return clip;
            }

            // 或者主 FBX 自带 Run clip
            return LoadFirstClipFromFbx(mainFbxPath, "Run");
        }

        private static AnimationClip LoadFirstClipFromFbx(string fbxPath, string preferName = null)
        {
            if (!File.Exists(Path.GetFullPath(fbxPath))) return null;
            var all = AssetDatabase.LoadAllAssetsAtPath(fbxPath);
            AnimationClip first = null;
            foreach (var a in all)
            {
                if (a is AnimationClip ac && !ac.name.StartsWith("__preview__"))
                {
                    if (!string.IsNullOrEmpty(preferName) && ac.name.IndexOf(preferName, StringComparison.OrdinalIgnoreCase) >= 0)
                        return ac;
                    if (first == null) first = ac;
                }
            }
            return first;
        }

        // 反射 — SelectiveVATBakerWindow 不在我们命名空间,但脚本可访问 ScriptableObject + 反射
        private static void BakeViaSelectiveBaker(GameObject target)
        {
            // 类型
            var bakerType = GetTypeByName("SelectiveVATBakerWindow");
            if (bakerType == null) throw new Exception("找不到 SelectiveVATBakerWindow 类型");

            var win = ScriptableObject.CreateInstance(bakerType);
            try
            {
                // _target = target
                SetField(win, "_target", target);
                // 自动 Z-up 检测
                var smr = target.GetComponentInChildren<SkinnedMeshRenderer>();
                if (smr != null && smr.sharedMesh != null)
                {
                    var size = smr.sharedMesh.bounds.size;
                    float x = Mathf.Abs(size.x), y = Mathf.Abs(size.y), z = Mathf.Abs(size.z);
                    bool zUp = z > y && z > x;
                    SetField(win, "_bakedMeshFacingX", zUp ? -90f : 0f);
                }

                // _outputRoot
                SetField(win, "_outputRoot", OutputRoot);

                // Refresh clips + Match defaults (会勾 Idle/Ready/Run/Die)
                Invoke(win, "RefreshClipsFromTarget");
                Invoke(win, "MatchDefaults");

                // 重点: 我们只勾选 Run (强制覆盖默认)
                var selectedField = bakerType.GetField("_selected", BindingFlags.NonPublic | BindingFlags.Instance);
                if (selectedField != null)
                {
                    var dict = selectedField.GetValue(win) as System.Collections.IDictionary;
                    if (dict != null)
                    {
                        // 先全置 false
                        var keys = new List<object>();
                        foreach (var k in dict.Keys) keys.Add(k);
                        foreach (var k in keys) dict[k] = false;
                        // 把 name == Run 的设 true
                        foreach (var k in keys)
                        {
                            var ac = k as AnimationClip;
                            if (ac == null) continue;
                            if (string.Equals(ac.name, "Run", StringComparison.OrdinalIgnoreCase))
                                dict[k] = true;
                        }
                    }
                }

                // BakeAll()
                Invoke(win, "BakeAll");
            }
            finally
            {
                UnityEngine.Object.DestroyImmediate(win);
            }
        }

        // -------- Reflection helpers --------
        private static Type GetTypeByName(string typeName)
        {
            foreach (var a in AppDomain.CurrentDomain.GetAssemblies())
            {
                foreach (var t in a.GetTypes())
                {
                    if (t.Name == typeName) return t;
                }
            }
            return null;
        }

        private static void SetField(object obj, string field, object value)
        {
            var f = obj.GetType().GetField(field, BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Public);
            if (f == null) throw new Exception($"Field not found: {field}");
            f.SetValue(obj, value);
        }

        private static void Invoke(object obj, string method)
        {
            var m = obj.GetType().GetMethod(method, BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Public);
            if (m == null) throw new Exception($"Method not found: {method}");
            m.Invoke(obj, null);
        }
    }
}