update at 2025-10-16 12:45:05

web/src/services/chat/MessageService.ts

@@ -0,0 +1,251 @@
+/**
+ * MessageService
+ * 负责消息的 CRUD 操作
+ * 
+ * 职责：
+ * - 消息的创建、读取、更新、删除
+ * - 消息状态管理
+ * - 消息查询和过滤
+ */
+
+import type { Message, Conversation } from '../../types/chat'
+import type { CreateMessageOptions, UpdateMessageOptions, MessageQueryResult } from './types'
+
+export class MessageService {
+  private conversations: Map<string, Conversation>
+
+  constructor(conversations: Map<string, Conversation>) {
+    this.conversations = conversations
+  }
+
+  /**
+   * 在指定对话中创建新消息
+   */
+  createMessage(conversationId: string, options: CreateMessageOptions): Message {
+    const conversation = this.conversations.get(conversationId)
+    if (!conversation) {
+      throw new Error(`Conversation not found: ${conversationId}`)
+    }
+
+    const message: Message = {
+      id: this.generateId(),
+      role: options.role,
+      content: options.content,
+      status: options.status || 'success',
+      timestamp: new Date(),
+      model: options.model,
+      tokens: options.tokens
+    }
+
+    conversation.messages.push(message)
+    conversation.updatedAt = new Date()
+
+    return message
+  }
+
+  /**
+   * 获取指定对话的所有消息
+   */
+  getMessages(conversationId: string): Message[] {
+    const conversation = this.conversations.get(conversationId)
+    return conversation?.messages || []
+  }
+
+  /**
+   * 根据 topicId 获取消息
+   */
+  getMessagesByTopicId(topicId: string): Message[] {
+    for (const conv of this.conversations.values()) {
+      if (conv.topicId === topicId) {
+        return conv.messages
+      }
+    }
+    return []
+  }
+
+  /**
+   * 获取指定消息
+   */
+  getMessage(conversationId: string, messageId: string): Message | undefined {
+    const conversation = this.conversations.get(conversationId)
+    if (!conversation) return undefined
+
+    return conversation.messages.find(m => m.id === messageId)
+  }
+
+  /**
+   * 查找消息及其位置信息
+   */
+  findMessage(messageId: string, topicId?: string): MessageQueryResult {
+    for (const conv of this.conversations.values()) {
+      if (topicId && conv.topicId !== topicId) continue
+
+      const index = conv.messages.findIndex(m => m.id === messageId)
+      if (index !== -1) {
+        return {
+          message: conv.messages[index],
+          conversation: conv,
+          index
+        }
+      }
+    }
+
+    return {
+      message: undefined,
+      conversation: undefined,
+      index: -1
+    }
+  }
+
+  /**
+   * 更新消息
+   */
+  updateMessage(
+    conversationId: string,
+    messageId: string,
+    options: UpdateMessageOptions
+  ): boolean {
+    const conversation = this.conversations.get(conversationId)
+    if (!conversation) return false
+
+    const message = conversation.messages.find(m => m.id === messageId)
+    if (!message) return false
+
+    // 更新消息字段
+    if (options.content !== undefined) {
+      message.content = options.content
+    }
+    if (options.status !== undefined) {
+      message.status = options.status
+    }
+    if (options.tokens !== undefined) {
+      message.tokens = options.tokens
+    }
+
+    conversation.updatedAt = new Date()
+    return true
+  }
+
+  /**
+   * 更新消息状态
+   */
+  updateMessageStatus(
+    conversationId: string,
+    messageId: string,
+    status: 'sending' | 'success' | 'error' | 'paused'
+  ): boolean {
+    return this.updateMessage(conversationId, messageId, { status })
+  }
+
+  /**
+   * 追加消息内容（用于流式响应）
+   */
+  appendMessageContent(
+    conversationId: string,
+    messageId: string,
+    content: string
+  ): boolean {
+    const conversation = this.conversations.get(conversationId)
+    if (!conversation) return false
+
+    const message = conversation.messages.find(m => m.id === messageId)
+    if (!message) return false
+
+    message.content += content
+    conversation.updatedAt = new Date()
+    return true
+  }
+
+  /**
+   * 删除消息
+   */
+  deleteMessage(conversationId: string, messageId: string): boolean {
+    const conversation = this.conversations.get(conversationId)
+    if (!conversation) return false
+
+    const index = conversation.messages.findIndex(m => m.id === messageId)
+    if (index === -1) return false
+
+    conversation.messages.splice(index, 1)
+    conversation.updatedAt = new Date()
+    return true
+  }
+
+  /**
+   * 删除指定消息之后的所有消息（包括该消息）
+   */
+  deleteMessagesAfter(conversationId: string, messageId: string): boolean {
+    const conversation = this.conversations.get(conversationId)
+    if (!conversation) return false
+
+    const index = conversation.messages.findIndex(m => m.id === messageId)
+    if (index === -1) return false
+
+    conversation.messages.splice(index)
+    conversation.updatedAt = new Date()
+    return true
+  }
+
+  /**
+   * 获取对话中最后一条用户消息
+   */
+  getLastUserMessage(conversationId: string): Message | undefined {
+    const conversation = this.conversations.get(conversationId)
+    if (!conversation) return undefined
+
+    for (let i = conversation.messages.length - 1; i >= 0; i--) {
+      if (conversation.messages[i].role === 'user') {
+        return conversation.messages[i]
+      }
+    }
+
+    return undefined
+  }
+
+  /**
+   * 获取对话中最后一条消息
+   */
+  getLastMessage(conversationId: string): Message | undefined {
+    const conversation = this.conversations.get(conversationId)
+    if (!conversation) return undefined
+
+    const messages = conversation.messages
+    return messages.length > 0 ? messages[messages.length - 1] : undefined
+  }
+
+  /**
+   * 获取消息预览文本
+   */
+  getMessagePreview(content: string, maxLength = 50): string {
+    if (!content) return ''
+    const text = content.replace(/\n/g, ' ').trim()
+    return text.length > maxLength ? text.slice(0, maxLength) + '...' : text
+  }
+
+  /**
+   * 获取对话中成功的消息（用于发送给 LLM）
+   */
+  getSuccessMessages(conversationId: string): Message[] {
+    const conversation = this.conversations.get(conversationId)
+    if (!conversation) return []
+
+    return conversation.messages.filter(m => 
+      m.status === 'success' || m.status === 'paused'
+    )
+  }
+
+  /**
+   * 获取最近的 N 条成功消息
+   */
+  getRecentSuccessMessages(conversationId: string, limit: number): Message[] {
+    const successMessages = this.getSuccessMessages(conversationId)
+    return successMessages.slice(-limit)
+  }
+
+  /**
+   * 生成唯一 ID
+   */
+  private generateId(): string {
+    return `${Date.now()}_${Math.random().toString(36).substr(2, 9)}`
+  }
+}