refactor(消息组件): 重构聊天消息加载逻辑为分页加载

将消息加载逻辑从父组件移动到MessageDetail组件内部实现
添加分页加载功能，支持下拉刷新历史消息
优化消息加载状态管理和错误处理

@@ -51,7 +51,15 @@
             :scroll-y="true"
             :scroll-top="scrollTop"
             :scroll-into-view="scrollIntoView"
+            :refresher-enabled="true"
+            :refresher-triggered="isLoadingMessages"
+            @refresherrefresh="handleRefresh"
           >
+            <!-- 数据加载完成提示 -->
+            <view v-if="!hasMoreMessages && !isInitialLoad && messages.length > 0 && hasTriedLoadMore" class="load-complete-tip">
+              <text class="tip-text">已加载完所有数据</text>
+            </view>
+
             <view
               v-for="(message, index) in messages"
               :key="index"
@@ -115,7 +123,7 @@
 <script setup>
 import { ref, computed, watch, nextTick } from 'vue'
 import Taro from '@tarojs/taro'
-import { sendChatAPI } from '@/api/chat'
+import { sendChatAPI, getChatListAPI } from '@/api/chat'
 import { useUserStore } from '@/stores/user'
 
 /**
@@ -152,28 +160,81 @@ const inputMessage = ref('')
 const scrollTop = ref(0)
 const scrollIntoView = ref('')
 
-// 模拟聊天消息数据
+// 聊天消息数据
 const messages = ref([])
 
+// 分页相关状态
+const PAGE_SIZE = 20 // 每页加载的消息数量
+const currentPage = ref(0)
+const hasMoreMessages = ref(true)
+const isLoadingMessages = ref(false)
+const isInitialLoad = ref(true)
+const hasTriedLoadMore = ref(false) // 是否已经尝试过手动上拉加载更多
+
 /**
- * 初始化聊天消息
+ * 加载聊天消息
+ * @param {boolean} isLoadMore - 是否为加载更多（下拉加载历史记录）
  */
-const initChatMessages = () => {
+const loadChatMessages = async (isLoadMore = false) => {
+  if (props.conversation?.type !== 'chat' || !props.conversation?.id) {
+    return
+  }
+
+  // 如果正在加载，则不继续加载
+  if (isLoadingMessages.value) {
+    return
+  }
+
+  // 对于scrolltoupper事件，如果没有更多消息则不加载
+   // 但对于下拉刷新，总是允许尝试加载
+   if (!hasMoreMessages.value && isLoadMore && !isInitialLoad.value) {
+     // 这里可以根据具体需求决定是否允许重新加载
+   }
+
   const userStore = useUserStore()
   const currentUserId = userStore.userInfo?.id
 
-  if (props.conversation?.type === 'chat') {
-    // 使用从API获取的真实聊天记录
-    if (props.conversation.chatMessages && props.conversation.chatMessages.length > 0) {
+  try {
+    isLoadingMessages.value = true
+
+    // 如果是加载更多，页码+1
+    const page = isLoadMore ? currentPage.value + 1 : 0
+
+    const response = await getChatListAPI({
+      conversation_id: props.conversation.id,
+      page: page,
+      limit: PAGE_SIZE
+    })
+
+    if (response.code && response.data) {
+      const newMessages = response.data.list || []
+
       // 转换API数据格式为组件需要的格式
-      messages.value = props.conversation.chatMessages.map(msg => ({
-        type: msg.created_by === currentUserId ? 'sent' : 'received', // 根据创建者ID判断
+      const formattedMessages = newMessages.map(msg => ({
+        type: msg.created_by === currentUserId ? 'sent' : 'received',
         content: msg.note || '',
         time: msg.created_time_desc || '',
-        id: msg.id
+        id: msg.id,
+        created_by: msg.created_by,
+        create_time: msg.create_time
       }))
+
+      if (isLoadMore) {
+        // 加载更多时，将新消息添加到列表顶部（历史消息）
+        messages.value = [...formattedMessages, ...messages.value]
+        currentPage.value = page
       } else {
-      // 如果没有历史消息，显示欢迎消息
+        // 初始加载时，直接设置消息列表
+        messages.value = formattedMessages
+        currentPage.value = 0
+        isInitialLoad.value = false
+      }
+
+      // 判断是否还有更多消息
+      hasMoreMessages.value = newMessages.length >= PAGE_SIZE
+
+      // 如果没有任何消息，显示欢迎消息
+      if (messages.value.length === 0 && !isLoadMore) {
         messages.value = [
           {
             type: 'received',
@@ -186,6 +247,15 @@ const initChatMessages = () => {
         ]
       }
     }
+  } catch (error) {
+    console.error('加载聊天消息失败:', error)
+    Taro.showToast({
+      title: '加载消息失败',
+      icon: 'error'
+    })
+  } finally {
+    isLoadingMessages.value = false
+  }
 }
 
 /**
@@ -212,7 +282,7 @@ const sendMessage = async () => {
   const messageContent = inputMessage.value.trim()
 
   try {
-    // 先添加到本地显示
+    // 先添加到本地显示（新消息添加到末尾）
     const newMessage = {
       type: 'sent',
       content: messageContent,
@@ -272,6 +342,20 @@ const sendMessage = async () => {
 }
 
 /**
+ * 处理下拉刷新
+ */
+const handleRefresh = async () => {
+  if (!isLoadingMessages.value) {
+    hasTriedLoadMore.value = true // 标记用户已经尝试手动加载更多
+    await loadChatMessages(true)
+  }
+  // 确保刷新状态被重置
+  setTimeout(() => {
+    isLoadingMessages.value = false
+  }, 100)
+}
+
+/**
  * 滚动到底部
  */
 const scrollToBottom = () => {
@@ -305,17 +389,29 @@ const handleClose = () => {
   scrollTop.value = 0
   scrollIntoView.value = ''
   messages.value = []
+  // 重置分页状态
+  currentPage.value = 0
+  hasMoreMessages.value = true
+  isLoadingMessages.value = false
+  isInitialLoad.value = true
+  hasTriedLoadMore.value = false // 重置手动加载标记
   emit('close')
 }
 
 /**
- * 监听对话变化，初始化消息
+ * 监听对话变化，加载消息
  */
 watch(
   () => props.conversation,
-  (newConversation) => {
+  async (newConversation) => {
     if (newConversation && visible.value) {
-      initChatMessages()
+      // 重置状态
+      currentPage.value = 0
+      hasMoreMessages.value = true
+      isInitialLoad.value = true
+      hasTriedLoadMore.value = false // 重置手动加载标记
+
+      await loadChatMessages()
       // 延迟滚动确保消息渲染完成
       setTimeout(() => {
         nextTick(() => {
@@ -330,9 +426,15 @@ watch(
 /**
  * 监听弹框显示状态
  */
-watch(visible, (newVisible) => {
+watch(visible, async (newVisible) => {
   if (newVisible && props.conversation) {
-    initChatMessages()
+    // 重置状态
+    currentPage.value = 0
+    hasMoreMessages.value = true
+    isInitialLoad.value = true
+    hasTriedLoadMore.value = false // 重置手动加载标记
+
+    await loadChatMessages()
     // 确保弹框完全打开后再滚动到底部
     setTimeout(() => {
       nextTick(() => {
@@ -408,6 +510,22 @@ watch(visible, (newVisible) => {
   overflow-y: auto;
 }
 
+// 数据加载完成提示样式
+.load-complete-tip {
+  text-align: center;
+  padding: 20rpx 0;
+  margin-bottom: 16rpx;
+
+  .tip-text {
+    font-size: 24rpx;
+    color: #999999;
+    background: #f5f5f5;
+    padding: 12rpx 24rpx;
+    border-radius: 20rpx;
+    display: inline-block;
+  }
+}
+
 .message-item {
   margin-bottom: 24rpx;
   display: flex;

@@ -103,7 +103,7 @@ import MessageDetail from '@/components/MessageDetail.vue'
 import { $ } from '@tarojs/extend'
 import Taro from '@tarojs/taro'
 // 导入接口
-import { getMessagesListAPI, getMessagesDetailAPI, getChatListAPI } from '@/api/chat'
+import { getMessagesListAPI, getMessagesDetailAPI } from '@/api/chat'
 
 // 默认头像
 const defaultAvatar = 'https://cdn.ipadbiz.cn/mlaj/images/icon_1.jpeg'
@@ -353,24 +353,8 @@ const onConversationClick = async (conversation) => {
                 selectedConversation.value = conversation
             }
         } else if (conversation.type === 'chat') {
-            // 获取聊天消息列表
-            const response = await getChatListAPI({ 
-                conversation_id: conversation.id,
-                page: 0,
-                limit: 50
-            })
-            if (response.code && response.data) {
-                // 更新conversation数据，包含聊天记录和接收者信息
-                selectedConversation.value = {
-                    ...conversation,
-                    chatMessages: response.data.list || [],
-                    receiver: response.data.receiver || {},
-                    name: response.data.receiver?.nickname || conversation.name,
-                    avatar: response.data.receiver?.avatar || conversation.avatar
-                }
-            } else {
+            // 聊天类型直接传递conversation，消息加载在MessageDetail组件内部处理
             selectedConversation.value = conversation
-            }
         } else {
             selectedConversation.value = conversation
         }