kev/Drawer/AI/ViewModels/MainWindowViewModel.cs

using AI.AgentIntegration;
using AI.Interface;
using AI.Models;
using AI.Models.Form;
using AI.Models.SpecialMessages;
using AI.Service;
using AI.Utils;
using AI.Workflow;
using System.Text;
using YamlDotNet.Serialization;
using YamlDotNet.Serialization.NamingConventions;
using Avalonia;
using Avalonia.Platform.Storage;
using Avalonia.Threading;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using Microsoft.SemanticKernel;
using Microsoft.SemanticKernel.ChatCompletion;
using System.ClientModel.Primitives;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Threading;

namespace AI.ViewModels
{
    public partial class MainWindowViewModel : ViewModelBase
    {
        public event Action? RequestScrollToBottom;
        public event Func<Task<IReadOnlyList<IStorageFile>>>? RequestFileSelection;

        private readonly IChatBackend _chatBackend;
        private readonly ChatSessionManager _sessionManager;
        private readonly IFormRegistry _formRegistry;
        private readonly IAppController _appController;

        private ChatSession? _currentSession;

        // 用于节流滚动调用，减少滚动频率
        private DateTime _lastScrollTime = DateTime.MinValue;
        private const int ScrollThrottleMs = 50; // 每50ms最多滚动一次

        [ObservableProperty]
        private string? _chatInput;

        [ObservableProperty]
        private ObservableCollection<ChatMessageModel> _chatMessages;

        [ObservableProperty]
        private ObservableCollection<ChatSessionItemViewModel> _sessions;

        private ChatSessionItemViewModel? _selectedSessionItem;

        [ObservableProperty]
        private ObservableCollection<PendingFileModel> _pendingFiles = new();

        private WorkflowMode _currentWorkflowMode = WorkflowMode.Ask;

        /// <summary>
        /// 工作流取消令牌源；执行中时非 null，用于取消或超时
        /// </summary>
        private CancellationTokenSource? _workflowCts;

        /// <summary>
        /// 工作流默认超时时间
        /// </summary>
        private static readonly TimeSpan DefaultWorkflowTimeout = TimeSpan.FromMinutes(10);

        /// <summary>
        /// 当前是否有工作流正在执行（用于显示取消按钮）
        /// </summary>
        [ObservableProperty]
        private bool _isWorkflowRunning;

        /// <summary>
        /// 当前工作模式（用于 ComboBox 绑定）
        /// </summary>
        public WorkflowMode CurrentWorkflowMode
        {
            get => _currentWorkflowMode;
            set
            {
                if (SetProperty(ref _currentWorkflowMode, value))
                {
                    OnPropertyChanged(nameof(CurrentWorkflowModeIndex));
                    OnWorkflowModeChanged();
                }
            }
        }

        /// <summary>
        /// 当前工作模式的索引（用于 ComboBox SelectedIndex 绑定）
        /// </summary>
        public int CurrentWorkflowModeIndex
        {
            get => (int)CurrentWorkflowMode;
            set
            {
                if (value >= 0 && value <= 1)
                {
                    CurrentWorkflowMode = (WorkflowMode)value;
                }
            }
        }


        public ChatSessionItemViewModel? SelectedSessionItem
        {
            get => _selectedSessionItem;
            set
            {
                if (SetProperty(ref _selectedSessionItem, value))
                {
                    if (value != null)
                    {
                        SwitchToSession(value.Session);
                    }
                }
            }
        }

        [ObservableProperty]
        private bool _isLastMessage;

        public MainWindowViewModel(IChatBackend chatBackend, ChatSessionManager sessionManager, IFormRegistry formRegistry, IAppController appController)
        {
            _chatBackend = chatBackend;
            _sessionManager = sessionManager;
            _formRegistry = formRegistry ?? throw new ArgumentNullException(nameof(formRegistry));
            _appController = appController ?? throw new ArgumentNullException(nameof(appController));

            ChatMessages = new ObservableCollection<ChatMessageModel>();
            Sessions = new ObservableCollection<ChatSessionItemViewModel>();

            // 订阅会话管理器事件
            _sessionManager.SessionsChanged += OnSessionsChanged;
            _sessionManager.CurrentSessionChanged += OnCurrentSessionChanged;

            // 初始化会话列表
            RefreshSessions();

            // 如果没有当前会话，创建一个新的
            if (_sessionManager.CurrentSession == null)
            {
                CreateNewSession();
            }
            else
            {
                SwitchToSession(_sessionManager.CurrentSession);
            }
        }

        /// <summary>
        /// 获取当前会话
        /// </summary>
        public ChatSession? CurrentSession => _currentSession;

        private void OnSessionsChanged(object? sender, EventArgs e)
        {
            Dispatcher.UIThread.InvokeAsync(RefreshSessions);
        }

        private void OnCurrentSessionChanged(object? sender, ChatSession? session)
        {
            Dispatcher.UIThread.InvokeAsync(() =>
            {
                SwitchToSession(session);
            });
        }

        private void RefreshSessions()
        {
            var currentSessionId = _currentSession?.Id;

            Sessions.Clear();
            foreach (var session in _sessionManager.GetAllSessions())
            {
                var item = new ChatSessionItemViewModel(session);
                if (session.Id == currentSessionId)
                {
                    item.IsSelected = true;
                    SelectedSessionItem = item;
                }
                Sessions.Add(item);
            }
        }

        /// <summary>
        /// 清理聊天界面内容
        /// </summary>
        private void ClearChatUI()
        {
            ChatMessages.Clear();
            PendingFiles.Clear();
            ChatInput = string.Empty;
            SelectedSessionItem = null;
            
            // 清除所有会话项的选中状态
            foreach (var item in Sessions)
            {
                item.IsSelected = false;
            }
        }

        private void SwitchToSession(ChatSession? session)
        {
            if (session == null)
            {
                // 如果没有会话，清理会话状态和 UI 内容
                _currentSession = null;
                ClearChatUI();
                return;
            }

            _currentSession = session;
            _sessionManager.CurrentSession = session;

            // 将当前可用表单 Schema（YAML）合并进本会话的 System 消息，存在则替换、避免重复追加
            session.EnsureFormsYamlInSystem(
                AppPrompt.InteractiveGuidePrompt,
                FormSchemaYamlGenerator.ToYaml(_formRegistry.GetAll()));

            // 恢复会话的工作模式
            CurrentWorkflowMode = session.WorkflowMode;

            // 从会话历史加载消息到 UI
            LoadMessagesFromSession(session);

            // 更新选中状态
            foreach (var item in Sessions)
            {
                item.IsSelected = item.Session.Id == session.Id;
                if (item.IsSelected)
                {
                    SelectedSessionItem = item;
                }
            }
        }

        /// <summary>
        /// 从会话存储构建 UI 消息列表（仅从 Store 读取，不解析 History）。
        /// </summary>
        private void LoadMessagesFromSession(ChatSession session)
        {
            ChatMessages.Clear();

            foreach (var entry in session.Store.Entries)
            {
                if (entry is Models.Store.TextConversationEntry text)
                {
                    if (text.Role == AuthorRole.System)
                    {
                        continue;
                    }

                    var authorType = text.Role == AuthorRole.User ? AuthorType.User : AuthorType.AI;
                    ChatMessages.Add(new ChatMessageModel(authorType, text.Content ?? string.Empty));
                }
                else if (entry is Models.Store.SpecialConversationEntry special)
                {
                    var specialMsg = SpecialMessageDeserializer.Deserialize(special.Type, special.Payload, _formRegistry);
                    if (specialMsg == null)
                    {
                        ChatMessages.Add(new ChatMessageModel(AuthorType.AI, $"[无法还原：{special.Type}]"));
                        continue;
                    }
                    var msgType = specialMsg.TypeName switch
                    {
                        "Form" => MessageType.Form,
                        "ParameterSet" => MessageType.ParameterSet,
                        "Table" => MessageType.Table,
                        "ColumnMatch" => MessageType.ColumnMatch,
                        "WorkflowStatus" => MessageType.WorkflowStatus,
                        "KnowledgeBase" => MessageType.KnowledgeBase,
                        "XyzLoadCard" => MessageType.XyzLoadCard,
                        _ => MessageType.Text
                    };
                    var model = new ChatMessageModel(AuthorType.AI, string.Empty, lastMessage: false)
                    {
                        Type = msgType,
                        SpecialContent = specialMsg
                    };
                    if (specialMsg is Models.SpecialMessages.KnowledgeBaseMessage kbMsg)
                    {
                        model.Message = "[知识库参考]\n" + (kbMsg.RawContent ?? string.Empty);
                    }

                    ChatMessages.Add(model);
                }
            }

            if (ChatMessages.Count > 0)
            {
                ChatMessages.Last()!.LastMessage = true;
            }
        }

        [RelayCommand]
        private void CreateNewSession()
        {
            var newSession = _sessionManager.CreateSession();
            newSession.WorkflowMode = CurrentWorkflowMode;
            // 通过 EnsureFormsYamlInSystem 写入引导词 + 表单 Schema YAML（存在则替换）
            newSession.EnsureFormsYamlInSystem(
                AppPrompt.InteractiveGuidePrompt,
                FormSchemaYamlGenerator.ToYaml(_formRegistry.GetAll()));
            SwitchToSession(newSession);
        }

        /// <summary>
        /// 工作模式改变时的处理
        /// </summary>
        private void OnWorkflowModeChanged()
        {
            if (_currentSession != null)
            {
                _currentSession.WorkflowMode = CurrentWorkflowMode;
            }
        }

        [RelayCommand]
        private void DeleteSession(string? sessionId)
        {
            if (string.IsNullOrEmpty(sessionId))
            {
                return;
            }

            var session = _sessionManager.GetSession(sessionId);
            if (session == null)
            {
                return;
            }

            // 如果删除的是当前会话，会话管理器会自动切换到其他会话
            _sessionManager.DeleteSession(sessionId);
        }

        [RelayCommand]
        private async Task SendMessage()
        {
            if ( _currentSession == null)
            {
                return;
            }

            var currentUserInput = ChatInput;
            ChatInput = string.Empty;

            List<PendingFileModel> currentPendingFiles = PendingFiles.ToList();
            PendingFiles.Clear();

            foreach (var file in currentPendingFiles)
            {
                if (string.IsNullOrEmpty(file.Name))
                {
                    continue;
                }

                var fileMessage = new ChatMessageModel(AuthorType.User, $"相关文件: {file.Name}")
                {
                    Type = MessageType.File,
                    FileName = file.Name,
                    FileSize = file.Size,
                };

                ChatMessages.Add(fileMessage);

                string userMessage = $"用户提供了\"{file.StorageFile.Path.LocalPath}\"文件";
                _currentSession.AddUserMessage(userMessage);
            }

            if (string.IsNullOrEmpty(currentUserInput))
            {
                return;
            }

            ChatMessages.ToList().ForEach(m => m.LastMessage = false);
            ChatMessages.Add(new ChatMessageModel(AuthorType.User, currentUserInput));

            // 根据工作模式选择处理方式
            if (CurrentWorkflowMode == WorkflowMode.Workflow)
            {
                // 工作流模式：使用 Planner + ReAct
                await ExecuteWorkflowAsync(currentUserInput);
            }
            else
            {
                // Ask 模式：普通对话
                await ExecuteAskModeAsync(currentUserInput);
            }

            // 更新会话列表项的显示信息
            var sessionItem = Sessions.FirstOrDefault(s => s.Session.Id == _currentSession.Id);
            sessionItem?.Refresh();
        }

        private void Rollback(string currentUserInput, int historyCountBefore, ChatMessageModel aiMessageModel)
        {
            if (_currentSession != null && _currentSession.History.Count > historyCountBefore)
            {
                _currentSession.History.RemoveAt(_currentSession.History.Count - 1);
                _currentSession.Store.RemoveLast(); // 与 Store 同步：移除刚加入的用户消息
            }
            ChatMessages.Remove(aiMessageModel);
            ChatInput = currentUserInput;
        }

        [RelayCommand]
        private async Task AddPendingFile()
        {
            try
            {
                // 通过事件请求文件选择
                var files = await RequestFileSelection?.Invoke();

                if (files != null && files.Count > 0)
                {
                    foreach (var file in files)
                    {
                        // 获取文件大小
                        var stream = await file.OpenReadAsync();
                        var size = stream.Length;
                        stream.Dispose();

                        PendingFiles.Add(new PendingFileModel
                        {
                            StorageFile = file,
                            Size = size
                        });
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine($"文件选择错误: {ex.Message}");
            }
        }

        [RelayCommand]
        private void RemovePendingFile(PendingFileModel file)
        {
            PendingFiles.Remove(file);
        }

        /// <summary>
        /// 为表单中的文件路径字段打开文件选择框，并将选中的路径写入该字段
        /// </summary>
        [RelayCommand]
        private async Task PickFileForField(FormFieldEntry? entry)
        {
            if (entry == null) return;
            try
            {
                var files = await RequestFileSelection?.Invoke();
                if (files != null && files.Count > 0 && files[0].Path != null)
                {
                    entry.CurrentValue = files[0].Path.LocalPath;
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine($"文件选择错误: {ex.Message}");
            }
        }

        /// <summary>
        /// 为参数集卡片中的文件路径项打开文件选择框，并将选中的路径写入该项
        /// </summary>
        [RelayCommand]
        private async Task PickFileForParameterItem(ParameterSetItem? item)
        {
            if (item == null) return;
            try
            {
                var files = await RequestFileSelection?.Invoke();
                if (files != null && files.Count > 0 && files[0].Path != null)
                {
                    item.ValueText = files[0].Path.LocalPath;
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine($"文件选择错误: {ex.Message}");
            }
        }

        /// <summary>
        /// 将参数集卡片中的当前值提交到网格化模块（设置网格化参数）
        /// </summary>
        [RelayCommand]
        private async Task ApplyParameterSet(ParameterSetMessage? paramMsg)
        {
            if (paramMsg == null || paramMsg.Items.Count == 0) return;
            try
            {
                var jobj = new Newtonsoft.Json.Linq.JObject();
                foreach (var item in paramMsg.Items)
                {
                    if (string.IsNullOrEmpty(item.Name)) continue;
                    if (item.FieldType == ParameterSetFieldType.Number &&
                        double.TryParse(item.ValueText?.Trim(), System.Globalization.NumberStyles.Any, null, out var num))
                        jobj[item.Name] = num;
                    else
                        jobj[item.Name] = item.ValueText ?? string.Empty;
                }
                var json = jobj.ToString();
                var action = AppAction.CreateSetParameters(json);
                var result = await _appController.ExecuteAsync(action);
                // 可选：在界面提示成功/失败
                if (!result.Success && !string.IsNullOrEmpty(result.Message))
                    System.Diagnostics.Debug.WriteLine($"应用参数: {result.Message}");
            }
            catch (Exception ex)
            {
                System.Diagnostics.Debug.WriteLine($"应用参数失败: {ex.Message}");
            }
        }

        /// <summary>
        /// 在指定会话中插入一条表单消息（AI 侧展示，供用户填写并提交）。同时写入该会话的 Store。
        /// 仅当目标会话为当前显示会话时更新 ChatMessages 并滚动，避免串会话。
        /// </summary>
        /// <param name="targetSession">要插入的会话；为 null 时使用当前选中会话（兼容旧调用）</param>
        public void AddFormMessage(FormDefinition definition, ChatSession? targetSession = null)
        {
            var formMsg = new FormRequestMessage(definition);
            var serialized = SpecialMessageSerializer.Serialize(formMsg);

            targetSession ??= _currentSession;
            targetSession?.AppendSpecialEntry("Form", serialized);

            if (targetSession != null && targetSession == _currentSession)
            {
                var message = new ChatMessageModel(AuthorType.AI, string.Empty, lastMessage: true)
                {
                    Type = MessageType.Form,
                    SpecialContent = formMsg,
                };
                ChatMessages.ToList().ForEach(m => m.LastMessage = false);
                ChatMessages.Add(message);
                RequestScrollToBottom?.Invoke();
            }
        }

        /// <summary>
        /// 在指定会话中插入一条参数集消息（将业务层 JSON 转为卡片展示）。同时写入该会话的 Store。
        /// 仅当目标会话为当前显示会话时更新 ChatMessages 并滚动，避免串会话。
        /// </summary>
        /// <param name="json">参数 JSON</param>
        /// <param name="title">卡片标题</param>
        /// <param name="targetSession">要插入的会话；为 null 时使用当前选中会话（兼容旧调用）</param>
        public void AddParameterSetMessage(string json, string? title = null, ChatSession? targetSession = null)
        {
            var paramMsg = new ParameterSetMessage();
            if (!string.IsNullOrWhiteSpace(title))
                paramMsg.Title = title;
            paramMsg.LoadFromJson(json ?? string.Empty);
            var serialized = SpecialMessageSerializer.Serialize(paramMsg);

            targetSession ??= _currentSession;
            targetSession?.AppendSpecialEntry("ParameterSet", serialized);

            if (targetSession != null && targetSession == _currentSession)
            {
                var message = new ChatMessageModel(AuthorType.AI, string.Empty, lastMessage: true)
                {
                    Type = MessageType.ParameterSet,
                    SpecialContent = paramMsg,
                };
                ChatMessages.ToList().ForEach(m => m.LastMessage = false);
                ChatMessages.Add(message);
                RequestScrollToBottom?.Invoke();
            }
        }

        /// <summary>
        /// 在指定会话中插入一张网格化参数设置综合卡片（Phase 0：Loading），并立即异步加载参数填充。
        /// 卡片自治完成「加载参数 → 用户编辑 → 点击生成 → 设置参数 + 执行成图」全流程。
        /// </summary>
        public async void AddGriddingParamCardMessage(ChatSession? targetSession = null)
        {
            var card = new Models.SpecialMessages.GriddingParamCardMessage();
            var serialized = SpecialMessageSerializer.Serialize(card);

            targetSession ??= _currentSession;
            targetSession?.AppendSpecialEntry("GriddingParamCard", serialized);

            ChatMessageModel? messageModel = null;
            if (targetSession != null && targetSession == _currentSession)
            {
                messageModel = new ChatMessageModel(AuthorType.AI, string.Empty, lastMessage: true)
                {
                    Type = MessageType.GriddingParamCard,
                    SpecialContent = card,
                };
                ChatMessages.ToList().ForEach(m => m.LastMessage = false);
                ChatMessages.Add(messageModel);
                RequestScrollToBottom?.Invoke();
            }

            // 卡片展示后立即异步加载参数
            await LoadGriddingParamCardItemsAsync(card);
        }

        /// <summary>
        /// 异步从业务层获取网格化参数，填充到卡片的 Items 中，并切换卡片到 Ready 阶段。
        /// </summary>
        private async Task LoadGriddingParamCardItemsAsync(Models.SpecialMessages.GriddingParamCardMessage card)
        {
            try
            {
                var result = await _appController.ExecuteAsync(
                    AppAction.CreateAction(AgentIntegration.AppActionType.GriddingModuleGetParameters));

                if (result.Success && !string.IsNullOrWhiteSpace(result.Message))
                {
                    var tempMsg = new Models.SpecialMessages.ParameterSetMessage();
                    tempMsg.LoadFromJson(result.Message);

                    await Avalonia.Threading.Dispatcher.UIThread.InvokeAsync(() =>
                    {
                        card.Items.Clear();
                        foreach (var item in tempMsg.Items)
                            card.Items.Add(item);
                        card.Phase = Models.SpecialMessages.GriddingParamCardPhase.Ready;
                        RequestScrollToBottom?.Invoke();
                    });
                }
                else
                {
                    await Avalonia.Threading.Dispatcher.UIThread.InvokeAsync(() =>
                    {
                        card.StatusMessage = result.Message ?? "获取网格化参数失败，请重试";
                        card.Phase = Models.SpecialMessages.GriddingParamCardPhase.Error;
                    });
                }
            }
            catch (Exception ex)
            {
                await Avalonia.Threading.Dispatcher.UIThread.InvokeAsync(() =>
                {
                    card.StatusMessage = $"加载参数失败：{ex.Message}";
                    card.Phase = Models.SpecialMessages.GriddingParamCardPhase.Error;
                });
            }
        }

        /// <summary>
        /// 在指定会话中插入一张散点文件加载综合卡片（Phase 0：等待用户选择文件）。
        /// </summary>
        public void AddXyzLoadCardMessage(ChatSession? targetSession = null)
        {
            var card = new Models.SpecialMessages.XyzLoadCardMessage();
            var serialized = SpecialMessageSerializer.Serialize(card);

            targetSession ??= _currentSession;
            targetSession?.AppendSpecialEntry("XyzLoadCard", serialized);

            if (targetSession != null && targetSession == _currentSession)
            {
                var message = new ChatMessageModel(AuthorType.AI, string.Empty, lastMessage: true)
                {
                    Type = MessageType.XyzLoadCard,
                    SpecialContent = card,
                };
                ChatMessages.ToList().ForEach(m => m.LastMessage = false);
                ChatMessages.Add(message);
                RequestScrollToBottom?.Invoke();
            }
        }

        /// <summary>
        /// 表单提交：收集表单值，作为结构化用户消息注入对话并请求 AI 继续
        /// </summary>
        [RelayCommand]
        private async Task SubmitForm(object? parameter)
        {
            if (parameter is not ChatMessageModel message ||
                message.Type != MessageType.Form ||
                message.SpecialContent is not FormRequestMessage formMsg ||
                _currentSession == null)
            {
                return;
            }

            var values = formMsg.GetValues();
            var sb = new StringBuilder();
            sb.Append("用户填写了表单【").Append(formMsg.Definition.Title).Append("】");
            if (!string.IsNullOrEmpty(formMsg.Definition.SubmitTarget))
            {
                sb.Append("（目标：").Append(formMsg.Definition.SubmitTarget).Append("）");
            }

            sb.Append("：");
            foreach (var kv in values)
            {
                sb.Append(" ").Append(kv.Key).Append("=").Append(kv.Value is string s ? s : kv.Value);
            }
            var userText = sb.ToString();

            ChatMessages.ToList().ForEach(m => m.LastMessage = false);
            ChatMessages.Add(new ChatMessageModel(AuthorType.User, userText));
            formMsg.SubmitLabel = "已提交";

            _currentSession.AddUserMessage(userText);

            var aiMessageModel = new ChatMessageModel(AuthorType.AI, string.Empty, lastMessage: true);
            ChatMessages.Add(aiMessageModel);
            RequestScrollToBottom?.Invoke();

            try
            {
                var response = await _chatBackend.AskAsync(userText, _currentSession, AppPrompt.InteractiveGuidePrompt);
                await Avalonia.Threading.Dispatcher.UIThread.InvokeAsync(() =>
                {
                    aiMessageModel.Message = response;
                    RequestScrollToBottom?.Invoke();
                });
            }
            catch (Exception ex)
            {
                await Avalonia.Threading.Dispatcher.UIThread.InvokeAsync(() =>
                {
                    aiMessageModel.Message = "处理表单提交时出错: " + ex.Message;
                    RequestScrollToBottom?.Invoke();
                });
            }
        }

        /// <summary>
        /// 取消当前正在执行的工作流
        /// </summary>
        [RelayCommand(CanExecute = nameof(CanCancelWorkflow))]
        private void CancelWorkflow()
        {
            _workflowCts?.Cancel();
        }

        private bool CanCancelWorkflow() => IsWorkflowRunning;

        /// <summary>
        /// 执行工作流模式
        /// </summary>
        private async Task ExecuteWorkflowAsync(string goal)
        {
            int historyCountBefore = _currentSession!.History.Count;

            // 若已有工作流在跑，先取消
            _workflowCts?.Cancel();
            _workflowCts?.Dispose();
            _workflowCts = new CancellationTokenSource();
            IsWorkflowRunning = true;
            ((CommunityToolkit.Mvvm.Input.IRelayCommand)CancelWorkflowCommand).NotifyCanExecuteChanged();

            // 创建工作流状态消息
            var workflowStatusMessage = new WorkflowStatusMessage
            {
                Title = "工作流执行中..."
            };

            var workflowMessage = new ChatMessageModel(AuthorType.AI, string.Empty, lastMessage: true)
            {
                Type = MessageType.WorkflowStatus,
                SpecialContent = workflowStatusMessage
            };

            await Dispatcher.UIThread.InvokeAsync(() =>
            {
                ChatMessages.Add(workflowMessage);
                RequestScrollToBottom?.Invoke();
            });

            try
            {
                // 创建 ReAct 工作流 Agent
                var agent = new Workflow.Agent(_chatBackend)
                {
                    Name = goal,
                    Description = goal
                };

                // 订阅事件
                agent.PlanCompleted += (sender, e) =>
                {
                    Dispatcher.UIThread.InvokeAsync(() =>
                    {
                        workflowStatusMessage.Title = $"工作流计划（共 {e.Plan.Steps.Count} 个步骤）";
                        var stepModels = Workflow.Agent.ConvertPlanToStepModels(e.Plan);
                        workflowStatusMessage.Steps = stepModels;
                    });
                };

                agent.StepStatusUpdated += (sender, e) =>
                {
                    Dispatcher.UIThread.InvokeAsync(() =>
                    {
                        // 更新对应步骤的状态
                        var stepModel = workflowStatusMessage.Steps.FirstOrDefault(s => s.Id == e.Step.Id);
                        if (stepModel != null)
                        {
                            stepModel.Status = e.Step.Status switch
                            {
                                PlanStepStatus.Pending => WorkflowStepStatus.Pending,
                                PlanStepStatus.Running => WorkflowStepStatus.Running,
                                PlanStepStatus.Completed => WorkflowStepStatus.Completed,
                                PlanStepStatus.Failed => WorkflowStepStatus.Failed,
                                _ => WorkflowStepStatus.Pending
                            };

                            if (!string.IsNullOrEmpty(e.Step.Result))
                            {
                                stepModel.OutputResult = e.Step.Result;
                            }
                        }
                    });
                };

                agent.StepThoughtUpdated += (sender, e) =>
                {
                    Dispatcher.UIThread.InvokeAsync(() =>
                    {
                        // 创建独立的思考消息，像 CodeAgent 一样顺序显示
                        var thoughtMessage = new ChatMessageModel(AuthorType.AI, e.Thought, lastMessage: false)
                        {
                            Type = MessageType.Text
                        };
                        
                        // 标记最后一条消息
                        if (ChatMessages.Count > 0)
                        {
                            ChatMessages.Last().LastMessage = false;
                        }
                        thoughtMessage.LastMessage = true;
                        
                        ChatMessages.Add(thoughtMessage);
                        RequestScrollToBottom?.Invoke();
                    });
                };

                // 执行工作流（带取消与超时）
                string result = await agent.ExecuteAsync(goal, _workflowCts.Token, DefaultWorkflowTimeout);

                // 更新最终结果
                await Dispatcher.UIThread.InvokeAsync(() =>
                {
                    // 确保之前的消息不是最后一条
                    if (ChatMessages.Count > 0)
                    {
                        ChatMessages.Last().LastMessage = false;
                    }
                    
                    workflowStatusMessage.Title = "工作流执行完成";
                    workflowMessage.Message = result;
                    workflowMessage.Type = MessageType.Text;
                    workflowMessage.SpecialContent = null;
                    workflowMessage.LastMessage = true;
                    RequestScrollToBottom?.Invoke();
                });

                // 添加到会话历史
                _currentSession.AddUserMessage(goal);
                _currentSession.AddAssistantMessage(result);
            }
            catch (OperationCanceledException)
            {
                await Dispatcher.UIThread.InvokeAsync(() =>
                {
                    workflowStatusMessage.Title = "工作流已取消或超时";
                    workflowMessage.Message = "工作流已被用户取消或已达到超时时间。";
                    workflowMessage.Type = MessageType.Text;
                    workflowMessage.SpecialContent = null;
                });
            }
            catch (Exception ex)
            {
                await Dispatcher.UIThread.InvokeAsync(() =>
                {
                    workflowStatusMessage.Title = "工作流执行失败";
                    workflowMessage.Message = $"执行失败: {ex.Message}";
                    workflowMessage.Type = MessageType.Text;
                    workflowMessage.SpecialContent = null;
                });

                if (_currentSession.History.Count > historyCountBefore)
                {
                    _currentSession.History.RemoveAt(_currentSession.History.Count - 1);
                }
            }
            finally
            {
                _workflowCts?.Dispose();
                _workflowCts = null;
                IsWorkflowRunning = false;
                _ = Dispatcher.UIThread.InvokeAsync(() =>
                    ((CommunityToolkit.Mvvm.Input.IRelayCommand)CancelWorkflowCommand).NotifyCanExecuteChanged());
            }
        }

        /// <summary>
        /// 执行 Ask 模式（普通对话）
        /// </summary>
        private async Task ExecuteAskModeAsync(string currentUserInput)
        {
            // 流式请求后端，传入当前会话
            // AskStreamAsync 内部会通过 ChatSession 添加用户消息和助手消息，并自动更新会话状态
            int historyCountBefore = _currentSession!.History.Count;
            
            // 创建 AI 消息模型用于流式更新
            var aiMessageModel = new ChatMessageModel(AuthorType.AI, string.Empty, lastMessage: true);
            ChatMessages.Add(aiMessageModel);
            RequestScrollToBottom?.Invoke();

            try
            {
                // 使用流式方式获取响应，每次收到片段立即更新 UI
                await foreach (var chunk in _chatBackend.AskStreamAsync(currentUserInput, _currentSession, AppPrompt.InteractiveGuidePrompt))
                {
                    // 在 UI 线程上更新消息内容
                    await Dispatcher.UIThread.InvokeAsync(() =>
                    {
                        // 使用 MarkdownBuilder.Append 进行高效的流式更新（LiveMarkdown.Avalonia 推荐方式）
                        aiMessageModel.MarkdownBuilder.Append(chunk);
                        // 使用节流滚动，减少滚动调用频率，避免滚动条跳跃
                        ThrottledScrollToBottom();
                    });
                }

                // 流式更新完成后，确保最后滚动一次到底部
                await Dispatcher.UIThread.InvokeAsync(() =>
                {
                    RequestScrollToBottom?.Invoke();
                });
            }
            catch (HttpOperationException) // 当网络异常时，我们将最后一条消息退回到输入框，方便用户再次点击发送
            {
                Rollback(currentUserInput, historyCountBefore, aiMessageModel);
                return;
            }
            catch (Exception)
            {
                Rollback(currentUserInput, historyCountBefore, aiMessageModel);
                return;
            }
        }

        /// <summary>
        /// 节流滚动到底部，用于流式更新时减少滚动调用频率
        /// </summary>
        private void ThrottledScrollToBottom()
        {
            var now = DateTime.Now;
            var timeSinceLastScroll = (now - _lastScrollTime).TotalMilliseconds;

            // 如果距离上次滚动超过节流时间，才执行滚动
            if (timeSinceLastScroll >= ScrollThrottleMs)
            {
                _lastScrollTime = now;
                RequestScrollToBottom?.Invoke();
            }
        }

        // ── 散点文件加载综合卡片命令 ─────────────────────────────────────────

        /// <summary>
        /// 为散点加载卡片中的文件路径字段打开文件选择框
        /// </summary>
        [RelayCommand]
        private async Task PickFileForXyzLoadCard(Models.SpecialMessages.XyzLoadCardMessage? card)
        {
            if (card == null) return;
            try
            {
                var files = await RequestFileSelection?.Invoke();
                if (files != null && files.Count > 0 && files[0].Path != null)
                {
                    card.FilePath = files[0].Path.LocalPath;
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine($"文件选择错误: {ex.Message}");
            }
        }

        /// <summary>
        /// 提交散点文件加载：直接调用应用层 API 完成「加载文件→获取列信息→展示列匹配」，
        /// 整个过程不经过 AI，由卡片本身驱动。
        /// </summary>
        [RelayCommand]
        private async Task SubmitXyzLoadCard(object? parameter)
        {
            if (parameter is not ChatMessageModel message ||
                message.Type != MessageType.XyzLoadCard ||
                message.SpecialContent is not Models.SpecialMessages.XyzLoadCardMessage card)
            {
                return;
            }

            var path = card.FilePath?.Trim();
            if (string.IsNullOrWhiteSpace(path))
            {
                return;
            }

            // 进入加载中状态
            card.IsLoading = true;
            card.StatusMessage = string.Empty;

            try
            {
                // ① 调用应用层加载散点文件
                var loadResult = await _appController.ExecuteAsync(AppAction.CreateLoadXyz(path));
                if (!loadResult.Success)
                {
                    card.StatusMessage = loadResult.Message ?? "文件加载失败，请检查路径是否正确";
                    card.IsLoading = false;
                    return;
                }

                // ② 构建 CSV 数据预览（本地解析，最多 20 行）
                var tableMessage = Utils.CsvPreviewHelper.TryBuildCsvPreviewTable(path, maxPreviewRows: 20);
                if (tableMessage != null)
                {
                    card.TablePreview = tableMessage;
                }

                // ③ 从应用层获取必需列与可用列
                var columnsResult = await _appController.ExecuteAsync(
                    AppAction.CreateAction(AgentIntegration.AppActionType.GriddingModuleGetColumns));

                if (!columnsResult.Success || string.IsNullOrWhiteSpace(columnsResult.Message))
                {
                    card.StatusMessage = columnsResult.Message ?? "无法获取列信息，请重试";
                    card.IsLoading = false;
                    return;
                }

                // ④ 解析列信息并填充列头匹配字段
                var columnDef = BuildColumnMatchDefinitionFromJson(columnsResult.Message);
                if (columnDef == null || columnDef.Fields.Count == 0)
                {
                    card.StatusMessage = "列信息格式无效，无法构建列头匹配";
                    card.IsLoading = false;
                    return;
                }

                card.ColumnMatchDefinition = columnDef;
                card.ColumnMatchFields.Clear();
                foreach (var field in columnDef.Fields)
                {
                    // 尝试智能预选：若可用列中有与必需列同名的项则预选它，否则选第一项
                    var defaultValue = field.Options?.FirstOrDefault(
                        o => string.Equals(o, field.Id, StringComparison.OrdinalIgnoreCase))
                        ?? field.Options?.FirstOrDefault()
                        ?? string.Empty;

                    card.ColumnMatchFields.Add(new Models.Form.FormFieldEntry
                    {
                        Id = field.Id,
                        Label = field.Label,
                        Type = Models.Form.FormFieldType.Choice,
                        Options = field.Options != null ? new List<string>(field.Options) : new List<string>(),
                        Required = true,
                        CurrentValue = defaultValue,
                    });
                }

                // ⑤ 切换到 FileLoaded 阶段（显示预览 + 列头匹配）
                card.Phase = Models.SpecialMessages.XyzLoadPhase.FileLoaded;
                RequestScrollToBottom?.Invoke();
            }
            catch (Exception ex)
            {
                card.StatusMessage = $"加载失败：{ex.Message}";
            }
            finally
            {
                card.IsLoading = false;
            }
        }

        /// <summary>
        /// 确认列头匹配：直接调用应用层 API 完成匹配，切换到 Completed 阶段，
        /// 最后生成统一信息摘要发给 AI 以继续后续对话。
        /// </summary>
        [RelayCommand]
        private async Task ConfirmXyzColumnMatch(object? parameter)
        {
            if (parameter is not ChatMessageModel message ||
                message.Type != MessageType.XyzLoadCard ||
                message.SpecialContent is not Models.SpecialMessages.XyzLoadCardMessage card ||
                _currentSession == null)
            {
                return;
            }

            if (card.ColumnMatchFields.Count == 0)
            {
                return;
            }

            // ① 构建匹配参数字典（必需列 → 选中的可用列）
            var mappingParams = card.ColumnMatchFields
                .Where(f => !string.IsNullOrEmpty(f.CurrentValue))
                .ToDictionary(f => f.Id, f => (object)f.CurrentValue);

            // ② 切换卡片状态（先禁用按钮）
            card.MatchButtonLabel = "正在确认...";

            try
            {
                // ③ 调用应用层执行列头匹配
                var matchResult = await _appController.ExecuteAsync(
                    AppAction.CreateAction(AgentIntegration.AppActionType.GriddingModuleMatchColumns, mappingParams));

                if (!matchResult.Success)
                {
                    card.MatchButtonLabel = "确认匹配";
                    card.StatusMessage = matchResult.Message ?? "列头匹配失败，请重试";
                    return;
                }

                await _appController.ExecuteAsync(
                    AppAction.CreateAction(AppActionType.GriddingModuleImport, null));

                // ④ 切换卡片到已完成状态
                card.MatchButtonLabel = "已确认";
                card.Phase = Models.SpecialMessages.XyzLoadPhase.Completed;
                card.StatusMessage = string.Empty;

                // ⑤ 生成统一信息摘要，作为用户消息发给 AI
                var sb = new StringBuilder();
                sb.AppendLine("散点文件加载完成，详情如下：");
                sb.Append("  • 文件路径：").AppendLine(card.FilePath);

                if (card.TablePreview != null)
                {
                    sb.Append("  • 数据：共 ").Append(card.TablePreview.TotalRowCount).Append(" 行，")
                      .Append(card.TablePreview.ColumnNames.Count).AppendLine(" 列");
                    if (card.TablePreview.ColumnNames.Count > 0)
                    {
                        sb.Append("  • 文件列：").AppendLine(string.Join(", ", card.TablePreview.ColumnNames));
                    }
                }

                if (card.ColumnMatchFields.Count > 0)
                {
                    var mappingDesc = string.Join("，", card.ColumnMatchFields
                        .Select(f => $"{f.Label} → {f.CurrentValue}"));
                    sb.Append("  • 列头匹配：").AppendLine(mappingDesc);
                }

                var summaryText = sb.ToString().TrimEnd();

                // ⑥ 加入对话流
                ChatMessages.ToList().ForEach(m => m.LastMessage = false);
                ChatMessages.Add(new ChatMessageModel(AuthorType.User, summaryText));
                _currentSession.AddUserMessage(summaryText);

                var aiMessageModel = new ChatMessageModel(AuthorType.AI, string.Empty, lastMessage: true);
                ChatMessages.Add(aiMessageModel);
                RequestScrollToBottom?.Invoke();

                // ⑦ 请求 AI 继续后续步骤
                try
                {
                    var response = await _chatBackend.AskAsync(summaryText, _currentSession, AppPrompt.InteractiveGuidePrompt);
                    await Avalonia.Threading.Dispatcher.UIThread.InvokeAsync(() =>
                    {
                        aiMessageModel.Message = response;
                        RequestScrollToBottom?.Invoke();
                    });
                }
                catch (Exception ex)
                {
                    await Avalonia.Threading.Dispatcher.UIThread.InvokeAsync(() =>
                    {
                        aiMessageModel.Message = "与 AI 通信时出错: " + ex.Message;
                        RequestScrollToBottom?.Invoke();
                    });
                }
            }
            catch (Exception ex)
            {
                card.MatchButtonLabel = "确认匹配";
                card.StatusMessage = $"操作失败：{ex.Message}";
            }
        }

        /// <summary>
        /// 点击网格化参数卡片中的"生成"按钮：收集用户编辑后的参数值，依次调用设置参数和执行成图，
        /// 完成后生成摘要作为用户消息注入对话并请求 AI 继续。
        /// </summary>
        [RelayCommand]
        private async Task SubmitGriddingParamCard(object? parameter)
        {
            if (parameter is not ChatMessageModel message ||
                message.Type != MessageType.GriddingParamCard ||
                message.SpecialContent is not Models.SpecialMessages.GriddingParamCardMessage card ||
                _currentSession == null)
            {
                return;
            }

            if (card.Phase != Models.SpecialMessages.GriddingParamCardPhase.Ready)
            {
                return;
            }

            card.GenerateButtonLabel = "生成中...";
            card.Phase = Models.SpecialMessages.GriddingParamCardPhase.Generating;

            try
            {
                // ① 收集当前编辑值，构建参数字典并序列化为 YAML
                var paramsDict = card.Items
                    .Where(i => !string.IsNullOrWhiteSpace(i.Name))
                    .ToDictionary(i => i.Name, i => (object)(i.ValueText ?? string.Empty));

                var serializer = new SerializerBuilder()
                    .WithNamingConvention(CamelCaseNamingConvention.Instance)
                    .Build();
                var paramsYaml = serializer.Serialize(paramsDict);

                // ② 设置参数
                var setAction = AppAction.CreateAction(
                    AgentIntegration.AppActionType.GriddingModuleSetParameters,
                    new Dictionary<string, object> { { "parameters", paramsYaml } });
                var setResult = await _appController.ExecuteAsync(setAction);

                if (!setResult.Success)
                {
                    card.StatusMessage = setResult.Message ?? "设置参数失败，请重试";
                    card.Phase = Models.SpecialMessages.GriddingParamCardPhase.Error;
                    card.GenerateButtonLabel = "生成";
                    return;
                }

                // ③ 执行成图
                var runResult = await _appController.ExecuteAsync(
                    AppAction.CreateAction(AgentIntegration.AppActionType.GriddingModuleRun));

                if (!runResult.Success)
                {
                    card.StatusMessage = runResult.Message ?? "成图失败，请重试";
                    card.Phase = Models.SpecialMessages.GriddingParamCardPhase.Error;
                    card.GenerateButtonLabel = "生成";
                    return;
                }

                // ④ 切换卡片到完成状态
                card.Phase = Models.SpecialMessages.GriddingParamCardPhase.Done;
                card.StatusMessage = string.Empty;

                // ⑤ 生成摘要，作为用户消息注入对话
                var sb = new StringBuilder();
                sb.AppendLine("网格化成图完成，详情如下：");
                foreach (var item in card.Items)
                {
                    if (!string.IsNullOrWhiteSpace(item.Name))
                        sb.Append("  • ").Append(item.Name).Append("：").AppendLine(item.ValueText ?? string.Empty);
                }
                var summaryText = sb.ToString().TrimEnd();

                // ⑥ 加入对话流
                ChatMessages.ToList().ForEach(m => m.LastMessage = false);
                ChatMessages.Add(new ChatMessageModel(AuthorType.User, summaryText));
                _currentSession.AddUserMessage(summaryText);

                var aiMessageModel = new ChatMessageModel(AuthorType.AI, string.Empty, lastMessage: true);
                ChatMessages.Add(aiMessageModel);
                RequestScrollToBottom?.Invoke();

                // ⑦ 请求 AI 继续
                try
                {
                    var response = await _chatBackend.AskAsync(summaryText, _currentSession, AppPrompt.InteractiveGuidePrompt);
                    await Avalonia.Threading.Dispatcher.UIThread.InvokeAsync(() =>
                    {
                        aiMessageModel.Message = response;
                        RequestScrollToBottom?.Invoke();
                    });
                }
                catch (Exception ex)
                {
                    await Avalonia.Threading.Dispatcher.UIThread.InvokeAsync(() =>
                    {
                        aiMessageModel.Message = "与 AI 通信时出错: " + ex.Message;
                        RequestScrollToBottom?.Invoke();
                    });
                }
            }
            catch (Exception ex)
            {
                card.StatusMessage = $"操作失败：{ex.Message}";
                card.Phase = Models.SpecialMessages.GriddingParamCardPhase.Error;
                card.GenerateButtonLabel = "生成";
            }
        }

        /// <summary>
        /// 从 GetColumns 返回的 JSON 构建列头匹配表单定义（内部复用 FormRequestNotifier 的逻辑）。
        /// </summary>
        private static Models.Form.FormDefinition? BuildColumnMatchDefinitionFromJson(string json)
        {
            try
            {
                var obj = Newtonsoft.Json.Linq.JObject.Parse(json);
                var required = obj["RequiredColumns"]?.ToObject<List<string>>();
                var available = obj["AvailableColumns"]?.ToObject<List<string>>();
                if (required == null || required.Count == 0 || available == null) return null;

                return new Models.Form.FormDefinition
                {
                    Id = "gridding-match-columns",
                    Title = "列头匹配",
                    SubmitTarget = "GriddingModuleMatchColumns",
                    SubmitLabel = "确认匹配",
                    Fields = required.Select(req => new Models.Form.FormField
                    {
                        Id = req,
                        Label = req,
                        Type = Models.Form.FormFieldType.Choice,
                        Options = new List<string>(available),
                        Required = true,
                    }).ToList(),
                };
            }
            catch
            {
                return null;
            }
        }
    }
}