feat: add general chat feature (without project/agent concept)

frontend/src/App.tsx

@@ -2,6 +2,7 @@ import { Routes, Route, Navigate } from 'react-router-dom'
 import MainLayout from './layouts/MainLayout'
 import HomePage from './pages/HomePage'
 import AgentChatPage from './pages/AgentChatPage'
+import ChatPage from './pages/ChatPage'
 import KnowledgePage from './pages/KnowledgePage'
 import HistoryPage from './pages/HistoryPage'
 
@@ -10,6 +11,7 @@ function App() {
     <Routes>
       <Route path="/" element={<MainLayout />}>
         <Route index element={<HomePage />} />
+        <Route path="chat" element={<ChatPage />} />
         <Route path="agent/:agentId" element={<AgentChatPage />} />
         <Route path="knowledge" element={<KnowledgePage />} />
         <Route path="history" element={<HistoryPage />} />

frontend/src/api/chatApi.ts

@@ -0,0 +1,139 @@
+/**
+ * 通用对话API
+ * 无需项目和智能体概念，纯大模型对话
+ */
+
+export interface GeneralConversation {
+  id: string
+  userId: string
+  title: string
+  modelName?: string
+  createdAt: string
+  updatedAt: string
+}
+
+export interface GeneralMessage {
+  id: string
+  conversationId: string
+  role: 'user' | 'assistant'
+  content: string
+  model?: string
+  tokens?: number
+  createdAt: string
+}
+
+export interface SendChatMessageData {
+  content: string
+  modelType: string
+  knowledgeBaseIds?: string[]
+  conversationId?: string
+}
+
+export interface ApiResponse<T = any> {
+  success: boolean
+  data?: T
+  message?: string
+}
+
+/**
+ * 发送消息（流式输出）
+ */
+export const sendMessageStream = async (
+  data: SendChatMessageData,
+  onChunk: (content: string) => void,
+  onComplete: (conversationId: string) => void,
+  onError: (error: Error) => void
+) => {
+  try {
+    console.log('🚀 [chatApi] 发送通用对话消息', data)
+
+    const response = await fetch('/api/v1/chat/stream', {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify(data),
+    })
+
+    if (!response.ok) {
+      throw new Error(`HTTP error! status: ${response.status}`)
+    }
+
+    const reader = response.body?.getReader()
+    if (!reader) {
+      throw new Error('Response body is null')
+    }
+
+    const decoder = new TextDecoder()
+    let buffer = ''
+    let conversationId = data.conversationId || ''
+
+    while (true) {
+      const { done, value } = await reader.read()
+
+      if (done) {
+        break
+      }
+
+      buffer += decoder.decode(value, { stream: true })
+      const lines = buffer.split('\n')
+      buffer = lines.pop() || ''
+
+      for (const line of lines) {
+        const trimmedLine = line.trim()
+        if (!trimmedLine || !trimmedLine.startsWith('data:')) {
+          continue
+        }
+
+        const dataStr = trimmedLine.slice(5).trim()
+
+        if (dataStr === '[DONE]') {
+          console.log('✅ [chatApi] 流式输出完成')
+          onComplete(conversationId)
+          return
+        }
+
+        try {
+          const chunk = JSON.parse(dataStr)
+          if (chunk.content) {
+            onChunk(chunk.content)
+          }
+          // 从第一个chunk中提取conversationId（如果是新对话）
+          if (!conversationId && chunk.conversationId) {
+            conversationId = chunk.conversationId
+          }
+        } catch (e) {
+          console.error('Failed to parse SSE chunk:', e)
+        }
+      }
+    }
+  } catch (error) {
+    console.error('❌ [chatApi] 发送消息失败:', error)
+    onError(error as Error)
+  }
+}
+
+/**
+ * 获取对话列表
+ */
+export const getConversations = async (): Promise<ApiResponse<GeneralConversation[]>> => {
+  const response = await fetch('/api/v1/chat/conversations')
+  return response.json()
+}
+
+/**
+ * 删除对话
+ */
+export const deleteConversation = async (id: string): Promise<ApiResponse> => {
+  const response = await fetch(`/api/v1/chat/conversations/${id}`, {
+    method: 'DELETE',
+  })
+  return response.json()
+}
+
+export default {
+  sendMessageStream,
+  getConversations,
+  deleteConversation,
+}
+

frontend/src/layouts/MainLayout.tsx

@@ -5,6 +5,7 @@ import {
   MenuFoldOutlined,
   MenuUnfoldOutlined,
   HomeOutlined,
+  MessageOutlined,
   ExperimentOutlined,
   FolderOpenOutlined,
   HistoryOutlined,
@@ -52,6 +53,11 @@ const MainLayout = () => {
       icon: <HomeOutlined />,
       label: '首页',
     },
+    {
+      key: '/chat',
+      icon: <MessageOutlined />,
+      label: '智能问答',
+    },
     {
       key: 'agents',
       icon: <ExperimentOutlined />,

frontend/src/pages/ChatPage.tsx

@@ -0,0 +1,179 @@
+import { useState, useEffect } from 'react'
+import { message } from 'antd'
+import chatApi, { type GeneralMessage } from '../api/chatApi'
+import MessageList from '../components/chat/MessageList'
+import MessageInput from '../components/chat/MessageInput'
+import ModelSelector, { type ModelType } from '../components/chat/ModelSelector'
+import { useKnowledgeBaseStore } from '../stores/useKnowledgeBaseStore'
+
+const ChatPage = () => {
+  const { knowledgeBases, fetchKnowledgeBases } = useKnowledgeBaseStore()
+  
+  const [messages, setMessages] = useState<GeneralMessage[]>([])
+  const [selectedModel, setSelectedModel] = useState<ModelType>('deepseek-v3')
+  const [sending, setSending] = useState(false)
+  const [streamingContent, setStreamingContent] = useState('')
+  const [currentConversationId, setCurrentConversationId] = useState<string>()
+
+  // 加载知识库列表
+  useEffect(() => {
+    fetchKnowledgeBases()
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [])
+
+  // 发送消息（流式）
+  const handleSendMessage = async (content: string, knowledgeBaseIds: string[]) => {
+    if (sending) return
+
+    console.log('🔵 [ChatPage] 发送消息', { content, knowledgeBaseIds, currentConversationId })
+
+    setSending(true)
+    setStreamingContent('')
+
+    // 添加用户消息到列表
+    const userMessage: GeneralMessage = {
+      id: `temp-${Date.now()}`,
+      conversationId: currentConversationId || 'temp',
+      role: 'user',
+      content,
+      createdAt: new Date().toISOString(),
+    }
+    setMessages(prev => [...prev, userMessage])
+
+    try {
+      let fullContent = ''
+
+      await chatApi.sendMessageStream(
+        {
+          content,
+          modelType: selectedModel,
+          knowledgeBaseIds,
+          conversationId: currentConversationId,
+        },
+        // onChunk
+        (chunk) => {
+          fullContent += chunk
+          setStreamingContent(fullContent)
+        },
+        // onComplete
+        (conversationId) => {
+          console.log('✅ [ChatPage] 对话完成', { conversationId })
+          
+          // 如果是新对话，保存conversationId
+          if (!currentConversationId && conversationId) {
+            setCurrentConversationId(conversationId)
+          }
+
+          // 添加完整的助手消息
+          const assistantMessage: GeneralMessage = {
+            id: `temp-assistant-${Date.now()}`,
+            conversationId: conversationId || currentConversationId || 'temp',
+            role: 'assistant',
+            content: fullContent,
+            model: selectedModel,
+            createdAt: new Date().toISOString(),
+          }
+          setMessages(prev => [...prev, assistantMessage])
+          setStreamingContent('')
+          setSending(false)
+        },
+        // onError
+        (error) => {
+          console.error('❌ [ChatPage] 发送失败:', error)
+          message.error('发送消息失败：' + error.message)
+          setStreamingContent('')
+          setSending(false)
+        }
+      )
+    } catch (err) {
+      console.error('❌ [ChatPage] 发送消息异常:', err)
+      message.error('发送消息失败')
+      setStreamingContent('')
+      setSending(false)
+    }
+  }
+
+  return (
+    <div style={{ height: '100%', display: 'flex', flexDirection: 'column' }}>
+      {/* 顶部工具栏 */}
+      <div style={{ 
+        padding: '12px 24px',
+        background: '#fff',
+        borderBottom: '1px solid #e8e8e8',
+        display: 'flex',
+        alignItems: 'center',
+        justifyContent: 'space-between',
+        flexShrink: 0,
+      }}>
+        <div style={{ fontSize: 16, fontWeight: 600 }}>
+          💬 智能问答
+        </div>
+
+        {/* 模型选择器 */}
+        <ModelSelector
+          value={selectedModel}
+          onChange={setSelectedModel}
+          disabled={sending}
+        />
+      </div>
+
+      {/* 聊天区域 */}
+      <div
+        style={{
+          flex: 1,
+          display: 'flex',
+          flexDirection: 'column',
+          overflow: 'hidden',
+          minHeight: 0,
+          background: '#fff',
+        }}
+      >
+        {/* 消息列表区域 */}
+        <div style={{ 
+          flex: 1, 
+          display: 'flex', 
+          flexDirection: 'column',
+          minHeight: 0,
+          overflow: 'hidden',
+        }}>
+          {messages.length === 0 && !sending ? (
+            <div style={{ 
+              flex: 1, 
+              display: 'flex', 
+              alignItems: 'center', 
+              justifyContent: 'center', 
+              background: '#fafafa' 
+            }}>
+              <div style={{ textAlign: 'center', color: '#999' }}>
+                <div style={{ fontSize: 48, marginBottom: 16 }}>💬</div>
+                <div style={{ fontSize: 18, fontWeight: 500, marginBottom: 8 }}>
+                  与AI自由对话
+                </div>
+                <div style={{ fontSize: 14 }}>
+                  直接提问，或使用@知识库引用文献
+                </div>
+              </div>
+            </div>
+          ) : (
+            <MessageList
+              messages={messages}
+              loading={sending}
+              streamingContent={streamingContent}
+            />
+          )}
+        </div>
+
+        {/* 消息输入 */}
+        <MessageInput
+          onSend={handleSendMessage}
+          loading={sending}
+          knowledgeBases={knowledgeBases}
+          placeholder="输入你的问题...（Shift+Enter换行，Enter发送）"
+        />
+      </div>
+    </div>
+  )
+}
+
+export default ChatPage
+