v3.1 + 批次0: 智能回复重构基线 - ApprovalMatcher + 关键词降级 + 文档速修 + v4.0任务书面化

backend/app/services/conversation/session_query_service.py

@@ -9,13 +9,14 @@
 
 import logging
 from datetime import datetime
-from typing import List, Optional, Tuple
+from typing import Dict, List, Optional, Tuple
 from uuid import UUID
 
 from sqlalchemy import and_, case, desc, func, select
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.models.conversation import Conversation
+from app.models.message import Message
 
 logger = logging.getLogger(__name__)
 
@@ -212,3 +213,108 @@ class SessionQueryService:
             raise ERR_CONVERSATION_NOT_FOUND
 
         return conversation
+
+    # --------------------------------------------------------------------------
+    # 获取员工历史消息（跨会话聚合）
+    # --------------------------------------------------------------------------
+    async def get_employee_history_messages(
+        self,
+        employee_id: str,
+        limit: int = 50,
+        before: Optional[str] = None,
+        current_conversation_id: Optional[str] = None,
+    ) -> Tuple[List[Message], bool, Dict[str, str]]:
+        """获取员工的历史消息（跨会话聚合）。
+
+        将同一员工的所有会话消息合并为一条时间线，按时间排序。
+        用于"历史会话"功能，让坐席查看员工过去的所有咨询记录。
+
+        查询逻辑：
+        1. 查询 conversations 表中 employee_id = ? 的所有会话ID
+        2. 查询 messages 表中 conversation_id IN (会话ID列表) 的消息
+        3. 如有 before 参数，获取该消息的 created_at，只查更早的消息
+        4. 按 created_at DESC 排序，取 limit + 1 条（多取1条判断 has_more）
+        5. 对涉及的每个会话，查询其 sender_type='employee' 的最早一条消息，
+           取前20字作为摘要
+        6. 返回消息列表 + has_more + conversation_summaries
+
+        Args:
+            employee_id: 员工企微 UserID
+            limit: 每页消息数量（默认50）
+            before: 游标消息ID，只查该消息之前的消息（向上翻页）
+            current_conversation_id: 当前会话ID（仅用于标记，不影响查询逻辑）
+
+        Returns:
+            tuple: (消息列表, 是否还有更多, {conversation_id: "前20字摘要"})
+        """
+        # 1. 查询该员工的所有会话ID
+        conv_stmt = select(Conversation.id).where(
+            Conversation.employee_id == employee_id
+        )
+        conv_result = await self.db.execute(conv_stmt)
+        conversation_ids = [row[0] for row in conv_result.all()]
+
+        if not conversation_ids:
+            # 该员工没有任何会话
+            return [], False, {}
+
+        # 2. 构建消息查询（跨会话聚合，按时间倒序）
+        stmt = select(Message).where(
+            Message.conversation_id.in_(conversation_ids)
+        ).order_by(Message.created_at.desc())
+
+        # 3. 如有 before 参数，获取该消息的 created_at，只查更早的消息
+        if before:
+            try:
+                before_stmt = select(Message.created_at).where(
+                    Message.id == str(before)
+                )
+                before_result = await self.db.execute(before_stmt)
+                before_time = before_result.scalar_one_or_none()
+                if before_time:
+                    stmt = stmt.where(Message.created_at < before_time)
+            except Exception:
+                pass  # before 参数格式错误，忽略
+
+        # 4. 取 limit + 1 条（多取1条判断 has_more）
+        stmt = stmt.limit(limit + 1)
+        result = await self.db.execute(stmt)
+        messages = list(result.scalars().all())
+
+        # 判断是否还有更多消息
+        has_more = len(messages) > limit
+        if has_more:
+            messages = messages[:limit]
+
+        # 5. 对涉及的每个会话，查询其 sender_type='employee' 的最早一条消息摘要
+        involved_conv_ids = list(set(m.conversation_id for m in messages))
+        conversation_summaries: Dict[str, str] = {}
+
+        for conv_id in involved_conv_ids:
+            # 查询该会话中员工发送的最早一条消息
+            summary_stmt = (
+                select(Message.content)
+                .where(
+                    and_(
+                        Message.conversation_id == conv_id,
+                        Message.sender_type == "employee",
+                    )
+                )
+                .order_by(Message.created_at.asc())
+                .limit(1)
+            )
+            summary_result = await self.db.execute(summary_stmt)
+            first_employee_msg = summary_result.scalar_one_or_none()
+            if first_employee_msg:
+                # 取前20字作为摘要
+                conversation_summaries[conv_id] = first_employee_msg[:20]
+            else:
+                conversation_summaries[conv_id] = "未知会话"
+
+        logger.debug(
+            f"查询员工历史消息: employee_id={employee_id}, "
+            f"conv_count={len(conversation_ids)}, "
+            f"msg_count={len(messages)}, has_more={has_more}"
+        )
+
+        return messages, has_more, conversation_summaries