#nullable enable
using System;
using System.Collections;
using System.IO;
using System.Linq;
using System.Reflection;
using Cysharp.Threading.Tasks;
using UnityEditor;
using UnityEngine;

namespace ShrinkContext.AppAdapter.Editor
{
    public sealed class ShrinkContextDiagnosticsWindow : EditorWindow
    {
        private readonly string[] _tabs = { "运行时", "组合配置", "容量基准" };
        private int _selectedTab;
        private Vector2 _runtimeScroll;
        private Vector2 _jsonScroll;
        private Vector2 _benchmarkScroll;
        private bool _autoRefresh = true;
        private ShrinkAppCompositionProfile? _profile;
        private string _compositionJson = string.Empty;
        private string? _compositionError;
        private int _unrelatedFibers = 1000;
        private int _reloadIterations = 100;
        private int _failureIterations = 25;
        private bool _benchmarkRunning;
        private ShrinkContextBenchmarkReport? _benchmarkReport;
        private string? _benchmarkError;

        [MenuItem("ShrinkSDK/Cordis/诊断与组合")]
        public static void ShowWindow()
        {
            var window = GetWindow<ShrinkContextDiagnosticsWindow>("Cordis Diagnostics");
            window.minSize = new Vector2(720f, 520f);
        }

        private void OnEnable()
        {
            _profile = ShrinkAppCompositionProfile.LoadDefault();
            RefreshCompositionJson();
        }

        private void OnInspectorUpdate()
        {
            if (_autoRefresh && _selectedTab == 0)
                Repaint();
        }

        private void OnGUI()
        {
            DrawToolbar();
            switch (_selectedTab)
            {
                case 0:
                    DrawRuntime();
                    break;
                case 1:
                    DrawComposition();
                    break;
                case 2:
                    DrawBenchmarks();
                    break;
            }
        }

        private void DrawToolbar()
        {
            EditorGUILayout.BeginHorizontal(EditorStyles.toolbar);
            _selectedTab = GUILayout.Toolbar(_selectedTab, _tabs, EditorStyles.toolbarButton);
            GUILayout.FlexibleSpace();
            if (_selectedTab == 0)
                _autoRefresh = GUILayout.Toggle(_autoRefresh, "自动刷新", EditorStyles.toolbarButton);
            EditorGUILayout.EndHorizontal();
        }

        private void DrawRuntime()
        {
            if (!Application.isPlaying)
            {
                EditorGUILayout.HelpBox("进入 Play Mode 后显示真实 ShrinkAppLoaderHost 状态。", MessageType.Info);
                DrawModDiagnostics();
                return;
            }

            var bootstrap = ShrinkAppLoaderBootstrapper.Instance;
            if (bootstrap == null || bootstrap.Host == null)
            {
                EditorGUILayout.HelpBox("当前 Play Mode 没有 ShrinkAppLoaderBootstrapper。", MessageType.Warning);
                DrawModDiagnostics();
                return;
            }

            var host = bootstrap.Host;
            var snapshot = host.Context.CaptureDiagnostic();
            EditorGUILayout.LabelField("ContextLoader", EditorStyles.boldLabel);
            EditorGUILayout.LabelField("状态", host.IsRunning ? "运行中" : "未启动");
            EditorGUILayout.LabelField("模块", $"active={host.ActiveModuleIds.Count}, waiting={host.WaitingModuleIds.Count}");
            EditorGUILayout.LabelField("余效应", $"bindings={snapshot.BindingCount}, indexedKeys={snapshot.Notifications.IndexedKeyCount}");
            EditorGUILayout.LabelField("通知", $"dispatch={snapshot.Notifications.DispatchCount}, candidateVisits={snapshot.Notifications.CandidateVisitCount}");

            DrawTransaction(host.Loader.LastTransaction);
            EditorGUILayout.Space(6f);
            EditorGUILayout.LabelField($"Fibers ({snapshot.Fibers.Count})", EditorStyles.boldLabel);
            _runtimeScroll = EditorGUILayout.BeginScrollView(_runtimeScroll);
            foreach (var fiber in snapshot.Fibers)
            {
                EditorGUILayout.BeginVertical(EditorStyles.helpBox);
                EditorGUILayout.BeginHorizontal();
                EditorGUILayout.LabelField($"#{fiber.Uid}  {fiber.Name}", EditorStyles.boldLabel);
                GUILayout.FlexibleSpace();
                EditorGUILayout.LabelField(fiber.Status.ToString(), GUILayout.Width(90f));
                EditorGUILayout.EndHorizontal();
                EditorGUILayout.LabelField("target", fiber.TargetProviderUids.Count == 0
                    ? "-"
                    : string.Join(", ", fiber.TargetProviderUids));
                EditorGUILayout.LabelField("inject", fiber.Inject.Count == 0 ? "-" : string.Join(", ", fiber.Inject));
                EditorGUILayout.LabelField("provide", fiber.Provide.Count == 0 ? "-" : string.Join(", ", fiber.Provide));
                if (fiber.InterceptKeys.Count > 0)
                    EditorGUILayout.LabelField("intercept", string.Join(", ", fiber.InterceptKeys));
                if (!string.IsNullOrWhiteSpace(fiber.ErrorMessage))
                    EditorGUILayout.HelpBox($"{fiber.ErrorType}: {fiber.ErrorMessage}", MessageType.Error);
                foreach (var dependency in fiber.Dependencies.Where(item => !item.IsSatisfied))
                {
                    EditorGUILayout.LabelField("waiting",
                        $"{dependency.Key} @ {dependency.Realm}; potential=[{string.Join(", ", dependency.PotentialProviderUids)}]");
                }
                EditorGUILayout.EndVertical();
            }
            EditorGUILayout.EndScrollView();
            DrawModDiagnostics();
        }

        private static void DrawTransaction(ShrinkLoaderTransactionDiagnostic? transaction)
        {
            EditorGUILayout.Space(6f);
            EditorGUILayout.LabelField("最近事务", EditorStyles.boldLabel);
            if (transaction == null)
            {
                EditorGUILayout.LabelField("尚无事务。");
                return;
            }

            EditorGUILayout.LabelField("阶段", $"#{transaction.Generation} {transaction.Phase}");
            if (!string.IsNullOrWhiteSpace(transaction.CurrentEntryId))
                EditorGUILayout.LabelField("条目", transaction.CurrentEntryId);
            if (!string.IsNullOrWhiteSpace(transaction.ErrorMessage))
            {
                var restore = transaction.RestoreAttempted
                    ? $"restore={transaction.PreviousCompositionRestored}"
                    : "restore=not-attempted";
                EditorGUILayout.HelpBox($"{transaction.ErrorType}: {transaction.ErrorMessage}\n{restore}",
                    transaction.PreviousCompositionRestored ? MessageType.Warning : MessageType.Error);
            }
        }

        private void DrawComposition()
        {
            var selected = (ShrinkAppCompositionProfile?)EditorGUILayout.ObjectField(
                "Profile", _profile, typeof(ShrinkAppCompositionProfile), false);
            if (selected != _profile)
            {
                _profile = selected;
                RefreshCompositionJson();
            }

            if (_profile == null)
            {
                EditorGUILayout.HelpBox(
                    "未选择 Composition Profile。可通过 Assets/Create/ShrinkSDK/Cordis/Composition Profile 创建。",
                    MessageType.Info);
                return;
            }

            EditorGUILayout.LabelField("条目", _profile.Entries.Count.ToString());
            EditorGUILayout.LabelField("未列出条目", _profile.IncludeUnlistedEntries ? "保留" : "排除");
            if (Application.isPlaying)
                EditorGUILayout.HelpBox("修改资产只影响下一次宿主启动，不会重写当前运行中的组合。", MessageType.Info);

            EditorGUILayout.BeginHorizontal();
            if (GUILayout.Button("从资产刷新 JSON"))
                RefreshCompositionJson();
            if (GUILayout.Button("将 JSON 写回资产"))
                ApplyCompositionJson();
            if (GUILayout.Button("导入 JSON..."))
                ImportCompositionJson();
            if (GUILayout.Button("导出 JSON..."))
                ExportCompositionJson();
            EditorGUILayout.EndHorizontal();

            if (!string.IsNullOrWhiteSpace(_compositionError))
                EditorGUILayout.HelpBox(_compositionError, MessageType.Error);

            _jsonScroll = EditorGUILayout.BeginScrollView(_jsonScroll);
            _compositionJson = EditorGUILayout.TextArea(_compositionJson, GUILayout.ExpandHeight(true));
            EditorGUILayout.EndScrollView();
        }

        private void RefreshCompositionJson()
        {
            try
            {
                _compositionJson = _profile != null ? _profile.ToJson() : string.Empty;
                _compositionError = null;
            }
            catch (Exception ex)
            {
                _compositionError = ex.Message;
            }
        }

        private void ApplyCompositionJson()
        {
            if (_profile == null)
                return;
            try
            {
                var document = ShrinkAppCompositionDocument.FromJson(_compositionJson);
                Undo.RecordObject(_profile, "Apply Cordis composition JSON");
                _profile.SetDocument(document);
                EditorUtility.SetDirty(_profile);
                AssetDatabase.SaveAssets();
                _compositionError = null;
            }
            catch (Exception ex)
            {
                _compositionError = ex.Message;
            }
        }

        private void ImportCompositionJson()
        {
            var path = EditorUtility.OpenFilePanel("导入 Cordis Composition", string.Empty, "json");
            if (string.IsNullOrWhiteSpace(path))
                return;
            try
            {
                _compositionJson = File.ReadAllText(path);
                ShrinkAppCompositionDocument.FromJson(_compositionJson);
                _compositionError = null;
            }
            catch (Exception ex)
            {
                _compositionError = ex.Message;
            }
        }

        private void ExportCompositionJson()
        {
            var path = EditorUtility.SaveFilePanel("导出 Cordis Composition", string.Empty,
                "ShrinkAppComposition", "json");
            if (string.IsNullOrWhiteSpace(path))
                return;
            try
            {
                ShrinkAppCompositionDocument.FromJson(_compositionJson);
                File.WriteAllText(path, _compositionJson);
                _compositionError = null;
            }
            catch (Exception ex)
            {
                _compositionError = ex.Message;
            }
        }

        private void DrawBenchmarks()
        {
            EditorGUILayout.HelpBox(
                "耗时只用于本机前后对比；自动测试验证倒排索引候选规模和失败恢复次数，不设置毫秒阈值。",
                MessageType.Info);
            _unrelatedFibers = Mathf.Max(0, EditorGUILayout.IntField("无关 fibers", _unrelatedFibers));
            _reloadIterations = Mathf.Max(1, EditorGUILayout.IntField("provider 替换次数", _reloadIterations));
            _failureIterations = Mathf.Max(1, EditorGUILayout.IntField("失败恢复次数", _failureIterations));

            EditorGUI.BeginDisabledGroup(_benchmarkRunning || Application.isPlaying);
            if (GUILayout.Button(_benchmarkRunning ? "运行中..." : "运行基准"))
                RunBenchmarksAsync().Forget();
            EditorGUI.EndDisabledGroup();
            if (Application.isPlaying)
                EditorGUILayout.HelpBox("容量基准仅在 Edit Mode 运行，避免污染当前游戏上下文。", MessageType.Warning);
            if (!string.IsNullOrWhiteSpace(_benchmarkError))
                EditorGUILayout.HelpBox(_benchmarkError, MessageType.Error);

            _benchmarkScroll = EditorGUILayout.BeginScrollView(_benchmarkScroll);
            if (_benchmarkReport != null)
            {
                EditorGUILayout.LabelField("Notify / Reload", EditorStyles.boldLabel);
                EditorGUILayout.LabelField("耗时", $"{_benchmarkReport.NotifyMilliseconds:F3} ms");
                EditorGUILayout.LabelField("dispatch", _benchmarkReport.NotificationDispatchCount.ToString());
                EditorGUILayout.LabelField("indexed candidate visits", _benchmarkReport.NotificationCandidateVisits.ToString());
                EditorGUILayout.LabelField("naive all-fiber visits", _benchmarkReport.NaiveFiberVisits.ToString());
                EditorGUILayout.LabelField("consumer apply", $"{_benchmarkReport.ConsumerApplyCount}/{_benchmarkReport.ReloadIterations}");
                EditorGUILayout.Space(6f);
                EditorGUILayout.LabelField("失败恢复", EditorStyles.boldLabel);
                EditorGUILayout.LabelField("耗时", $"{_benchmarkReport.RestoreMilliseconds:F3} ms");
                EditorGUILayout.LabelField("恢复成功", $"{_benchmarkReport.RestoredFailureCount}/{_benchmarkReport.FailureIterations}");
                EditorGUILayout.LabelField("GC 管理堆差值（噪声参考）", $"{_benchmarkReport.ManagedMemoryDeltaBytes} bytes");
            }
            EditorGUILayout.EndScrollView();
            DrawModDiagnostics();
        }

        private async UniTaskVoid RunBenchmarksAsync()
        {
            _benchmarkRunning = true;
            _benchmarkError = null;
            try
            {
                _benchmarkReport = await ShrinkContextBenchmarkRunner.RunAsync(
                    _unrelatedFibers, _reloadIterations, _failureIterations);
            }
            catch (Exception ex)
            {
                _benchmarkError = ex.ToString();
            }
            finally
            {
                _benchmarkRunning = false;
                Repaint();
            }
        }

        private static void DrawModDiagnostics()
        {
            EditorGUILayout.Space(8f);
            EditorGUILayout.LabelField("外部程序集常驻", EditorStyles.boldLabel);
            var snapshot = CaptureOptionalModDiagnostic();
            if (snapshot == null)
            {
                EditorGUILayout.LabelField("ShrinkModFramework 未载入或未提供诊断 API。");
                return;
            }

            var current = ReadProperty(snapshot, "CurrentRevisionCount");
            var resident = ReadProperty(snapshot, "ResidentRevisionCount");
            var bytes = ReadProperty(snapshot, "EstimatedResidentBytes");
            var limit = ReadProperty(snapshot, "SoftLimit");
            var exceeded = ReadProperty(snapshot, "IsSoftLimitExceeded");
            EditorGUILayout.LabelField("汇总",
                $"current={current}, resident={resident}, bytes={bytes}, softLimit={limit}, exceeded={exceeded}");

            if (ReadProperty(snapshot, "ResidentRevisions") is not IEnumerable revisions)
                return;
            foreach (var revision in revisions)
            {
                if (revision == null)
                    continue;
                var marker = Equals(ReadProperty(revision, "IsCurrent"), true) ? "current" : "resident";
                var name = ReadProperty(revision, "AssemblyName");
                var hash = ReadProperty(revision, "Revision")?.ToString() ?? string.Empty;
                if (hash.Length > 12)
                    hash = hash.Substring(0, 12);
                EditorGUILayout.LabelField($"{marker}: {name}",
                    $"{hash}, {ReadProperty(revision, "LoadedBytes")} bytes");
            }
        }

        private static object? CaptureOptionalModDiagnostic()
        {
            var type = AppDomain.CurrentDomain.GetAssemblies()
                .Select(assembly => assembly.GetType("ShrinkModFramework.ShrinkModDiagnostics", false))
                .FirstOrDefault(candidate => candidate != null);
            var method = type?.GetMethod("CaptureExternalAssemblies", BindingFlags.Public | BindingFlags.Static);
            return method?.Invoke(null, new object?[] { null });
        }

        private static object? ReadProperty(object instance, string name) =>
            instance.GetType().GetProperty(name, BindingFlags.Public | BindingFlags.Instance)?.GetValue(instance);
    }
}