feat(ai-chat): 优化加载状态动画与流式消息过渡

pages_tool/ai-chat/ai-chat-message.vue

@@ -17,7 +17,7 @@
       
       <!-- 消息列表 -->
       <view 
-        v-for="(message, index) in messages.filter(msg => msg.content && msg.content.trim() !== '')" 
+        v-for="(message, index) in messages.filter(msg => msg.type === 'loading' || (msg.content && msg.content.trim() !== ''))" 
         :key="getMessageKey(message, index)"  
         :id="getMessageKey(message, index)"
         class="message-item"
@@ -159,14 +159,23 @@
               </view>
               
 
-              <!-- 加载中状态 -->
+              <!-- 加载/处理中状态 -->
               <view v-else-if="message.type === 'loading'" class="loading-content">
-                <view class="loading-dots">
-                  <text class="dot"></text>
-                  <text class="dot"></text>
-                  <text class="dot"></text>
+                <view class="loading-typing">
+                  <view class="typing-dots">
+                    <text class="dot"></text>
+                    <text class="dot"></text>
+                    <text class="dot"></text>
+                  </view>
+                  <text class="loading-text">
+                    <text class="loading-status">{{ message.loadingText || 'AI正在思考' }}</text>
+                    <text class="loading-ellipsis">
+                      <text class="ellipsis-dot">.</text>
+                      <text class="ellipsis-dot">.</text>
+                      <text class="ellipsis-dot">.</text>
+                    </text>
+                  </text>
                 </view>
-                <text class="loading-text">AI正在思考中...</text>
               </view>
               
               <!-- 操作按钮 -->
@@ -558,9 +567,15 @@ export default {
      }
      // 会话未变化且已有消息 → 跳过加载，保留当前消息
    },
-               // 新增：组件销毁时清除防抖定时器
+               // 新增：组件销毁时清除所有定时器
                beforeDestroy() {
                  if (this.scrollTimer) clearTimeout(this.scrollTimer);
+                 // 清理所有加载状态定时器
+                 this.messages.forEach(msg => {
+                   if (msg._rotationTimer) {
+                     clearInterval(msg._rotationTimer);
+                   }
+                 });
                },
     created() {
       this.messages = [...this.initialMessages]
@@ -900,17 +915,25 @@ async loadChatHistoryIfExist() {
       this.messages.push(userMessage)
       this.inputText = ''
       
-      // 显示AI正在输入
+        // 显示AI正在处理 - 带状态轮换提示
       const loadingMessage = {
         id: ++this.messageId,
         role: 'ai',
         type: 'loading',
         content: '',
-        timestamp: Date.now()
+        timestamp: Date.now(),
+        loadingText: 'AI正在思考',
+        _loadingIndex: 0
       }
       this.shouldScrollToBottom = true
       this.messages.push(loadingMessage)
       
+      // 启动处理状态文字轮换
+      this._startLoadingTextRotation(loadingMessage)
+      
+      // 等待 Vue 先渲染 loading 动画，再发起请求
+      await this.$nextTick()
+      
       try {
         // 直接发送消息（跳过健康检查，避免健康检查接口格式不匹配导致误判）
         // 如果服务不可用，实际发送时会抛出异常，由 catch 块处理
@@ -925,7 +948,7 @@ async loadChatHistoryIfExist() {
         console.error('AI服务调用失败:', error)
         
         // 移除加载状态
-        this.messages = this.messages.filter(msg => msg.type !== 'loading')
+        this._removeLoadingMessages()
         
         // 显示错误消息
         const errorMessage = {
@@ -955,7 +978,7 @@ async loadChatHistoryIfExist() {
       })
       
       // 移除加载状态
-      this.messages = this.messages.filter(msg => msg.type !== 'loading')
+      this._removeLoadingMessages()
       
       // 更新会话ID
       if (response.conversationId) {
@@ -982,134 +1005,193 @@ async loadChatHistoryIfExist() {
       this.$emit('ai-response', aiMessage)
     },
  // 发送流式消息（自动适配 H5 / 微信小程序）
- async sendStreamMessage(userMessage) {
-   // 创建流式消息对象
-   const streamMessage = {
-     id: ++this.messageId,
-     role: 'ai',
-     type: 'text',
-     content: '',
-     timestamp: Date.now(),
-     isStreaming: true
-   };
-   // 标记正在流式响应
-   this.isStreaming = true;
-   // 移除加载状态，添加流式消息
-   this.messages = this.messages.filter(msg => msg.type !== 'loading');
-   this.shouldScrollToBottom = true;
-   this.messages.push(streamMessage);
+async sendStreamMessage(userMessage) {
+  // 找到已有的 loading 消息，复用它在 DOM 中的位置，实现无缝过渡
+  const loadingIdx = this.messages.findIndex(msg => msg.type === 'loading')
+  if (loadingIdx === -1) {
+    // 安全回退：没有 loading 消息时创建新消息
+    const fallback = {
+      id: ++this.messageId,
+      role: 'ai',
+      type: 'text',
+      content: '',
+      timestamp: Date.now(),
+      isStreaming: true
+    }
+    this.isStreaming = true
+    this.messages.push(fallback)
+    this.scrollToBottom()
 
-   // 添加消息后立即滚动一次
-   this.$nextTick(() => {
-     this.scrollToBottom();
-   });
+    try {
+      // #ifdef H5
+      await aiService.sendHttpStream(userMessage,
+        (chunk) => { fallback.content += chunk; this.scrollToBottom() },
+        (result) => this._finishStream(fallback, result))
+      // #endif
+      // #ifdef MP-WEIXIN
+      await aiService.sendStreamMessage(userMessage,
+        (chunk) => { fallback.content += chunk; this.scrollToBottom() },
+        (result) => this._finishStream(fallback, result))
+      // #endif
+    } catch (error) {
+      this._handleStreamError(fallback)
+    }
+    return
+  }
 
-   try {
-     // #ifdef H5
-     await aiService.sendHttpStream(
-       userMessage,
-       (chunk) => {
-        // 实时更新内容
-        streamMessage.content += chunk;
-        // 流式更新时滚动到底部显示最新内容（防抖）
-        this.scrollToBottom();
+  this.isStreaming = true
+  const loadingMsg = this.messages[loadingIdx]
+  this._stopLoadingTextRotation(loadingMsg)
+  loadingMsg.loadingText = '正在接收回复'
+
+  let transformed = false
+
+  const transformOnFirstChunk = () => {
+    if (transformed) return this.messages[loadingIdx]
+    transformed = true
+    const msg = this.messages[loadingIdx]
+    msg.type = 'text'
+    msg.content = ''
+    this.$set(msg, 'isStreaming', true)
+    this.$set(msg, 'actions', [])
+    delete msg.loadingText
+    delete msg._loadingIndex
+    return msg
+  }
+
+  try {
+    // #ifdef H5
+    await aiService.sendHttpStream(
+      userMessage,
+      (chunk) => {
+        const msg = transformOnFirstChunk()
+        msg.content += chunk
+        this.scrollToBottom()
       },
-       (completeResult) => {
-         // 流结束回调
-         let convId = '';
-
-         if (typeof completeResult !== 'string') {
-           convId = completeResult.conversation_id || '';
-         }
-
-         // 标记流式结束
-         streamMessage.isStreaming = false;
-         this.isStreaming = false;
-
-         // 检查内容是否为空，如果为空则移除该消息
-         if (!streamMessage.content || streamMessage.content.trim() === '') {
-           this.messages = this.messages.filter(msg => msg.id !== streamMessage.id);
-           return;
-         }
-
-         // 保存会话 ID
-         if (convId) {
-           this.currentConversationId = convId;
-           aiService.setConversationId(convId);
-           this.saveConversationIdToLocal(convId);
-         }
-         
-         // 流结束后再滚动到底部
-         this.$nextTick(() => {
-           this.scrollToBottom();
-         });
-
-         // 触发事件
-         this.$emit('ai-response', streamMessage);
-       }
-     );
-     // #endif
-
-     // #ifdef MP-WEIXIN
-     // ===== 微信小程序: 使用 WebSocket =====
-     await aiService.sendStreamMessage(
-       userMessage,
-       (chunk) => {
-        // 实时更新内容
-        streamMessage.content += chunk;
-        // 流式更新时滚动到底部显示最新内容（防抖）
-        this.scrollToBottom();
-      },
-       (completeResult) => {
-        // 流结束回调
-        let convId = completeResult?.conversation_id || '';
-
-        // 标记流式结束
-        streamMessage.isStreaming = false;
-        this.isStreaming = false;
-
-        // 检查内容是否为空，如果为空则移除该消息
-        if (!streamMessage.content || streamMessage.content.trim() === '') {
-          this.messages = this.messages.filter(msg => msg.id !== streamMessage.id);
-          return;
-        }
-
-        // 保存会话 ID
-        if (convId) {
-          this.currentConversationId = convId;
-          aiService.setConversationId(convId);
-          this.saveConversationIdToLocal(convId);
-        }
-        
-        // 流结束后再滚动到底部
-        this.$nextTick(() => {
-          this.scrollToBottom();
-        });
-
-        // 触发事件
-        this.$emit('ai-response', streamMessage);
+      (completeResult) => {
+        const msg = this.messages[loadingIdx]
+        if (!this._finishStream(msg, completeResult)) return
       }
-     );
-     // #endif
-   } catch (error) {
-     console.error('流式请求失败:', error);
-     // 标记流式结束
-     this.isStreaming = false;
-     // 移除流式消息
-     this.messages = this.messages.filter(msg => msg.id !== streamMessage.id);
-     // 显示错误
-     const errorMsg = {
-       id: ++this.messageId,
-       role: 'ai',
-       type: 'text',
-       content: '抱歉，服务暂时不可用，请稍后重试。',
-       timestamp: Date.now(),
-       actions: [{ id: 1, text: '重试', type: 'retry' }]
-     };
-     this.messages.push(errorMsg);
-     this.$emit('ai-response', errorMsg);
-   }
- },
+    )
+    // #endif
+
+    // #ifdef MP-WEIXIN
+    await aiService.sendStreamMessage(
+      userMessage,
+      (chunk) => {
+        const msg = transformOnFirstChunk()
+        msg.content += chunk
+        this.scrollToBottom()
+      },
+      (completeResult) => {
+        const msg = this.messages[loadingIdx]
+        if (!this._finishStream(msg, completeResult)) return
+      }
+    )
+    // #endif
+  } catch (error) {
+    console.error('流式请求失败:', error)
+    this.isStreaming = false
+
+    if (!transformed) {
+      // 在第一个 chunk 到达前出错 → 移除 loading 消息
+      this._removeLoadingMessages()
+    } else {
+      // 流传输中出错 → 移除空的流式消息
+      const msg = this.messages[loadingIdx]
+      if (msg && (!msg.content || msg.content.trim() === '')) {
+        this.messages.splice(loadingIdx, 1)
+      }
+    }
+
+    const errorMsg = {
+      id: ++this.messageId,
+      role: 'ai',
+      type: 'text',
+      content: '抱歉，服务暂时不可用，请稍后重试。',
+      timestamp: Date.now(),
+      actions: [{ id: 1, text: '重试', type: 'retry' }]
+    }
+    this.messages.push(errorMsg)
+    this.$emit('ai-response', errorMsg)
+  }
+},
+
+// 完成流式消息处理（共用逻辑）
+_finishStream(msg, result) {
+  msg.isStreaming = false
+  this.isStreaming = false
+
+  if (!msg.content || msg.content.trim() === '') {
+    this._removeLoadingMessages()
+    return false
+  }
+
+  if (result) {
+    const convId = typeof result === 'string' ? '' : (result.conversation_id || '')
+    if (convId) {
+      this.currentConversationId = convId
+      aiService.setConversationId(convId)
+      this.saveConversationIdToLocal(convId)
+    }
+  }
+
+  msg.actions = [
+    { id: 1, text: '有帮助', type: 'like' },
+    { id: 2, text: '没帮助', type: 'dislike' }
+  ]
+
+  this.$nextTick(() => this.scrollToBottom())
+  this.$emit('ai-response', msg)
+  return true
+},
+
+// 流式请求出错处理
+_handleStreamError(msg) {
+  console.error('流式请求失败')
+  this.isStreaming = false
+  this.messages = this.messages.filter(m => m.id !== msg.id)
+
+  const errorMsg = {
+    id: ++this.messageId,
+    role: 'ai',
+    type: 'text',
+    content: '抱歉，服务暂时不可用，请稍后重试。',
+    timestamp: Date.now(),
+    actions: [{ id: 1, text: '重试', type: 'retry' }]
+  }
+  this.messages.push(errorMsg)
+  this.$emit('ai-response', errorMsg)
+},
+    // 加载状态文字轮换 - 让AI看起来在处理不同阶段
+    _startLoadingTextRotation(loadingMsg) {
+      const statusTexts = [
+        'AI正在思考',
+        'AI正在分析',
+        'AI正在检索',
+        'AI正在生成'
+      ]
+      loadingMsg._rotationTimer = setInterval(() => {
+        loadingMsg._loadingIndex = (loadingMsg._loadingIndex + 1) % statusTexts.length
+        loadingMsg.loadingText = statusTexts[loadingMsg._loadingIndex]
+      }, 2000)
+    },
+
+    // 停止加载状态文字轮换
+    _stopLoadingTextRotation(loadingMsg) {
+      if (loadingMsg && loadingMsg._rotationTimer) {
+        clearInterval(loadingMsg._rotationTimer)
+        loadingMsg._rotationTimer = null
+      }
+    },
+
+    // 移除加载消息并清理定时器
+    _removeLoadingMessages() {
+      const loadingMsgs = this.messages.filter(msg => msg.type === 'loading');
+      loadingMsgs.forEach(msg => this._stopLoadingTextRotation(msg));
+      this.messages = this.messages.filter(msg => msg.type !== 'loading');
+    },
+
     generateAIResponse(userMessage) {
       const responses = {
         '你好': '您好！我是AI智能客服，很高兴为您服务！有什么可以帮助您的吗？',
@@ -1713,10 +1795,16 @@ async loadChatHistoryIfExist() {
         role: 'ai',
         type: 'loading',
         content: '',
-        timestamp: Date.now()
+        timestamp: Date.now(),
+        loadingText: 'AI正在思考',
+        _loadingIndex: 0
       }
       
       this.messages.push(loadingMessage)
+      this._startLoadingTextRotation(loadingMessage)
+
+      // 等待 Vue 渲染 loading 动画
+      await this.$nextTick()
 
       try {
         // 使用AI服务获取回复
@@ -1732,7 +1820,7 @@ async loadChatHistoryIfExist() {
         console.error('AI服务调用失败:', error)
         
         // 移除加载状态
-        this.messages = this.messages.filter(msg => msg.type !== 'loading')
+        this._removeLoadingMessages()
         
         // 显示错误消息
         const errorMessage = {
@@ -1900,6 +1988,13 @@ async loadChatHistoryIfExist() {
     
     // 清空聊天记录
     clearMessages() {
+      // 清理所有加载状态定时器
+      this.messages.forEach(msg => {
+        if (msg._rotationTimer) {
+          clearInterval(msg._rotationTimer)
+          msg._rotationTimer = null
+        }
+      })
       // 清空消息数组
       this.messages = []
       // 重置消息 ID
@@ -2562,31 +2657,68 @@ $radius-lg: 36rpx;
             align-items: center;
             padding: 32rpx 0;
             
-            .loading-dots {
+            .loading-typing {
               display: flex;
-              margin-right: 16rpx;
+              flex-direction: column;
+              align-items: flex-start;
+              gap: 12rpx;
               
-              .dot {
-                width: 14rpx;
-                height: 14rpx;
-                border-radius: 50%;
-                background-color: $color-primary;
-                margin: 0 6rpx;
-                animation: dotPulse 1.5s infinite ease-in-out;
+              .typing-dots {
+                display: flex;
+                align-items: center;
                 
-                &:nth-child(2) {
-                  animation-delay: 0.2s;
-                }
+                .dot {
+                  width: 14rpx;
+                  height: 14rpx;
+                  border-radius: 50%;
+                  background-color: $color-primary;
+                  margin: 0 6rpx;
+                  animation: dotPulse 1.5s infinite ease-in-out;
                   
-                &:nth-child(3) {
-                  animation-delay: 0.4s;
+                  &:nth-child(2) {
+                    animation-delay: 0.2s;
+                  }
+                  
+                  &:nth-child(3) {
+                    animation-delay: 0.4s;
+                  }
                 }
               }
-            }
               
-            .loading-text {
-              color: $color-text-light;
-              font-size: 26rpx;
+              .loading-text {
+                color: $color-text-light;
+                font-size: 24rpx;
+                display: flex;
+                align-items: center;
+                
+                .loading-status {
+                  color: $color-primary;
+                  font-weight: 500;
+                  transition: opacity 0.3s ease;
+                }
+                
+                .loading-ellipsis {
+                  display: inline-flex;
+                  margin-left: 4rpx;
+                  
+                  .ellipsis-dot {
+                    animation: ellipsisBlink 1.4s infinite ease-in-out;
+                    opacity: 0;
+                    
+                    &:nth-child(1) {
+                      animation-delay: 0s;
+                    }
+                    
+                    &:nth-child(2) {
+                      animation-delay: 0.2s;
+                    }
+                    
+                    &:nth-child(3) {
+                      animation-delay: 0.4s;
+                    }
+                  }
+                }
+              }
             }
           }
 
@@ -3478,6 +3610,15 @@ $radius-lg: 36rpx;
   }
 }
 
+@keyframes ellipsisBlink {
+  0%, 100% {
+    opacity: 0;
+  }
+  50% {
+    opacity: 1;
+  }
+}
+
 @keyframes wave {
   0%, 100% {
     transform: scaleY(0.5);