完成历史信息查询，并且可以通过内容模糊查询，通过时间查询，通过消息类型查询

src/main/resources/com/bao/dating/mapper/ChatRecordsMapper.xml

@@ -31,4 +31,30 @@
             )
     </insert>
 
+    <!-- 根据两个用户ID及可选条件查询聊天记录 (按发送时间倒序) - PageHelper 会自动处理分页 -->
+    <select id="selectByUsersAndConditions" resultType="com.bao.dating.pojo.entity.ChatRecords">
+        SELECT
+        chat_id, sender_user_id, receiver_user_id, message_content, message_type,
+        read_status, read_time, send_time, message_status, created_at, updated_at
+        FROM chat_records
+        WHERE (
+            (sender_user_id = #{currentUserId} AND receiver_user_id = #{targetUserId})
+            OR (sender_user_id = #{targetUserId} AND receiver_user_id = #{currentUserId})
+        )
+        AND message_status = 1
+        <!-- 动态条件 -->
+        <if test="messageContent != null and messageContent != ''">
+            AND message_content LIKE CONCAT('%', #{messageContent}, '%')
+        </if>
+        <if test="startTime != null">
+            AND send_time >= #{startTime}
+        </if>
+        <if test="endTime != null">
+            AND send_time &lt;= #{endTime}
+        </if>
+        <if test="messageType != null">
+            AND message_type = #{messageType}
+        </if>
+        ORDER BY send_time DESC
+    </select>
 </mapper>