feat:拆分 handlePageChange 为子函数（减少复杂度）

src/views/Community/components/DynamicNewsCard.js

@@ -57,30 +57,21 @@ const usePagination = ({ allCachedEvents, total, cachedCount, dispatch, toast })
     return allCachedEvents.slice(startIndex, endIndex).filter(event => event !== null);
   }, [allCachedEvents, currentPage, pageSize]);
 
-  // 翻页处理（智能预加载）
-  const handlePageChange = useCallback(async (newPage) => {
-    // 🔍 诊断日志 - 记录翻页开始状态
-    console.log('[handlePageChange] 开始翻页', {
-      currentPage,
-      newPage,
-      pageSize,
-      totalPages,
-      hasMore,
-      total,
-      allCachedEventsLength: allCachedEvents.length,
-      cachedCount
-    });
-
-    // 0. 首先检查目标页数据是否已完整缓存
-    const targetPageStartIndex = (newPage - 1) * pageSize;
+  /**
+   * 子函数1: 检查目标页缓存状态
+   * @param {number} targetPage - 目标页码
+   * @returns {Object} { isTargetPageCached, targetPageInfo }
+   */
+  const checkTargetPageCache = useCallback((targetPage) => {
+    const targetPageStartIndex = (targetPage - 1) * pageSize;
     const targetPageEndIndex = targetPageStartIndex + pageSize;
     const targetPageData = allCachedEvents.slice(targetPageStartIndex, targetPageEndIndex);
     const validTargetData = targetPageData.filter(e => e !== null);
     const expectedCount = Math.min(pageSize, total - targetPageStartIndex);
     const isTargetPageCached = validTargetData.length >= expectedCount;
 
-    console.log('[handlePageChange] 目标页缓存检查', {
-      newPage,
+    console.log('[checkTargetPageCache] 目标页缓存检查', {
+      targetPage,
       targetPageStartIndex,
       targetPageEndIndex,
       targetPageDataLength: targetPageData.length,
@@ -89,32 +80,63 @@ const usePagination = ({ allCachedEvents, total, cachedCount, dispatch, toast })
       isTargetPageCached
     });
 
-    // 1. 判断翻页类型：连续翻页（上一页/下一页）还是跳转翻页（点击页码/输入跳转）
-    const isSequentialNavigation = Math.abs(newPage - currentPage) === 1;
+    return {
+      isTargetPageCached,
+      targetPageInfo: {
+        startIndex: targetPageStartIndex,
+        endIndex: targetPageEndIndex,
+        validCount: validTargetData.length,
+        expectedCount
+      }
+    };
+  }, [allCachedEvents, pageSize, total]);
+
+  /**
+   * 子函数2: 计算预加载范围
+   * @param {number} targetPage - 目标页码
+   * @param {number} fromPage - 来源页码
+   * @returns {Array<number>} 预加载页码数组
+   */
+  const calculatePreloadRange = useCallback((targetPage, fromPage) => {
+    const isSequentialNavigation = Math.abs(targetPage - fromPage) === 1;
 
-    // 2. 计算预加载范围
     let preloadRange;
     if (isSequentialNavigation) {
       // 连续翻页：前后各2页（共5页）
-      const start = Math.max(1, newPage - 2);
-      const end = Math.min(totalPages, newPage + 2);
+      const start = Math.max(1, targetPage - 2);
+      const end = Math.min(totalPages, targetPage + 2);
       preloadRange = Array.from(
         { length: end - start + 1 },
         (_, i) => start + i
       );
     } else {
       // 跳转翻页：只加载当前页
-      preloadRange = [newPage];
+      preloadRange = [targetPage];
     }
 
-    // 3. 检查哪些页面的数据还未缓存（检查是否包含 null 或超出数组长度）
+    console.log('[calculatePreloadRange] 计算预加载范围', {
+      targetPage,
+      fromPage,
+      isSequentialNavigation,
+      preloadRange
+    });
+
+    return preloadRange;
+  }, [totalPages]);
+
+  /**
+   * 子函数3: 查找缺失页面
+   * @param {Array<number>} preloadRange - 预加载范围
+   * @returns {Array<number>} 缺失页码数组
+   */
+  const findMissingPages = useCallback((preloadRange) => {
     const missingPages = preloadRange.filter(page => {
       const pageStartIndex = (page - 1) * pageSize;
       const pageEndIndex = pageStartIndex + pageSize;
 
       // 如果该页超出数组范围，说明未缓存
       if (pageEndIndex > allCachedEvents.length) {
-        console.log(`[missingPages] 页面${page}超出数组范围`, {
+        console.log(`[findMissingPages] 页面${page}超出数组范围`, {
           pageStartIndex,
           pageEndIndex,
           allCachedEventsLength: allCachedEvents.length
@@ -128,7 +150,7 @@ const usePagination = ({ allCachedEvents, total, cachedCount, dispatch, toast })
       const expectedCount = Math.min(pageSize, total - pageStartIndex);
       const hasNullOrIncomplete = validData.length < expectedCount;
 
-      console.log(`[missingPages] 页面${page}检查`, {
+      console.log(`[findMissingPages] 页面${page}检查`, {
         pageStartIndex,
         pageEndIndex,
         pageDataLength: pageData.length,
@@ -140,33 +162,40 @@ const usePagination = ({ allCachedEvents, total, cachedCount, dispatch, toast })
       return hasNullOrIncomplete;
     });
 
-    console.log('[handlePageChange] 缺失页面检测完成', {
+    console.log('[findMissingPages] 缺失页面检测完成', {
       preloadRange,
       missingPages,
       missingPagesCount: missingPages.length
     });
 
-    // 4. 如果目标页已缓存，立即切换页码，然后在后台静默预加载其他页
-    if (isTargetPageCached && missingPages.length > 0 && hasMore) {
-      console.log('[DynamicNewsCard] 目标页已缓存，立即切换', {
-        currentPage,
-        newPage,
-        缺失页面: missingPages,
-        目标页已缓存: true
-      });
+    return missingPages;
+  }, [allCachedEvents, pageSize, total]);
 
-      // 立即切换页码（用户无感知延迟）
-      setCurrentPage(newPage);
+  /**
+   * 子函数4: 加载页面数据
+   * @param {Array<number>} missingPages - 缺失页码数组
+   * @param {number} targetPage - 目标页码
+   * @param {boolean} silentMode - 静默模式（后台预加载）
+   * @returns {Promise<boolean>} 是否加载成功
+   */
+  const loadPages = useCallback(async (missingPages, targetPage, silentMode = false) => {
+    if (!silentMode) {
+      // 显示 loading 状态
+      setLoadingPage(targetPage);
+    }
 
-      // 在后台静默预加载其他缺失页面（拆分为单页请求）
     try {
-        console.log('[DynamicNewsCard] 开始后台预加载', {
-          缺失页面: missingPages,
-          每页数量: pageSize
+      console.log(`[loadPages] 开始加载`, {
+        missingPages,
+        targetPage,
+        silentMode,
+        pageSize
       });
 
       // 拆分为单页请求，避免 per_page 动态值导致后端返回空数据
       for (const page of missingPages) {
+        console.log(`[loadPages] 开始加载第 ${page} 页`);
+
         await dispatch(fetchDynamicNews({
           page: page,
           per_page: pageSize,  // 固定值（5或10），不使用动态计算
@@ -174,86 +203,96 @@ const usePagination = ({ allCachedEvents, total, cachedCount, dispatch, toast })
           clearCache: false
         })).unwrap();
 
-          console.log(`[DynamicNewsCard] 后台预加载第 ${page} 页完成`);
+        console.log(`[loadPages] 第 ${page} 页加载完成`);
       }
 
-        console.log('[DynamicNewsCard] 后台预加载全部完成', {
-          预加载页面: missingPages
+      console.log('[loadPages] 所有页面加载完成', {
+        missingPages,
+        silentMode
       });
+
+      return true;
     } catch (error) {
-        console.error('[DynamicNewsCard] 后台预加载失败', error);
-        // 静默失败，不影响用户体验
-      }
+      console.error('[loadPages] 加载失败', error);
 
-      return; // 提前返回，不执行下面的加载逻辑
-    }
-
-    // 5. 如果目标页未缓存，显示 loading 并等待加载完成
-    if (missingPages.length > 0 && hasMore) {
-      console.log('[DynamicNewsCard] 目标页未缓存，显示loading', {
-        currentPage,
-        newPage,
-        翻页类型: isSequentialNavigation ? '连续翻页' : '跳转翻页',
-        预加载范围: preloadRange,
-        缺失页面: missingPages,
-        每页数量: pageSize,
-        目标页已缓存: false
-      });
-
-      try {
-        // 设置加载状态（显示"正在加载第X页..."）
-        setLoadingPage(newPage);
-
-        // 拆分为单页请求，避免 per_page 动态值导致后端返回空数据
-        for (const page of missingPages) {
-          console.log(`[DynamicNewsCard] 开始加载第 ${page} 页`);
-
-          await dispatch(fetchDynamicNews({
-            page: page,
-            per_page: pageSize,  // 固定值（5或10），不使用动态计算
-            pageSize: pageSize,  // 传递原始 pageSize，用于正确计算索引
-            clearCache: false
-          })).unwrap();
-
-          console.log(`[DynamicNewsCard] 第 ${page} 页加载完成`);
-        }
-
-        console.log('[DynamicNewsCard] 所有缺失页面加载完成', {
-          缺失页面: missingPages
-        });
-
-        // 数据加载成功后才更新当前页码
-        setCurrentPage(newPage);
-      } catch (error) {
-        console.error('[DynamicNewsCard] 翻页加载失败', error);
-
-        // 显示错误提示
+      if (!silentMode) {
+        // 非静默模式下显示错误提示
         toast({
           title: '加载失败',
-          description: `无法加载第 ${newPage} 页数据，请稍后重试`,
+          description: `无法加载第 ${targetPage} 页数据，请稍后重试`,
           status: 'error',
           duration: 3000,
           isClosable: true,
           position: 'top'
         });
+      }
 
-        // 加载失败时不更新页码，保持在当前页
+      return false;
     } finally {
+      if (!silentMode) {
         // 清除加载状态
         setLoadingPage(null);
       }
+    }
+  }, [dispatch, pageSize, toast]);
+
+  // 翻页处理（智能预加载）- 使用子函数重构
+  const handlePageChange = useCallback(async (newPage) => {
+    // 🔍 诊断日志 - 记录翻页开始状态
+    console.log('[handlePageChange] 开始翻页', {
+      currentPage,
+      newPage,
+      pageSize,
+      totalPages,
+      hasMore,
+      total,
+      allCachedEventsLength: allCachedEvents.length,
+      cachedCount
+    });
+
+    // 步骤1: 检查目标页缓存状态
+    const { isTargetPageCached } = checkTargetPageCache(newPage);
+
+    // 步骤2: 计算预加载范围
+    const preloadRange = calculatePreloadRange(newPage, currentPage);
+
+    // 步骤3: 查找缺失页面
+    const missingPages = findMissingPages(preloadRange);
+
+    // 步骤4: 根据情况加载数据
+    if (isTargetPageCached && missingPages.length > 0 && hasMore) {
+      // 场景A: 目标页已缓存，立即切换，后台静默预加载其他页
+      console.log('[handlePageChange] 目标页已缓存，立即切换 + 后台预加载', {
+        currentPage,
+        newPage,
+        缺失页面: missingPages
+      });
+
+      setCurrentPage(newPage);
+      await loadPages(missingPages, newPage, true); // 静默模式
+    } else if (missingPages.length > 0 && hasMore) {
+      // 场景B: 目标页未缓存，显示 loading 并等待加载完成
+      console.log('[handlePageChange] 目标页未缓存，显示 loading', {
+        currentPage,
+        newPage,
+        缺失页面: missingPages
+      });
+
+      const success = await loadPages(missingPages, newPage, false); // 非静默模式
+      if (success) {
+        setCurrentPage(newPage);
+      }
     } else if (missingPages.length === 0) {
-      // 只有在确实不需要加载时才直接切换
+      // 场景C: 所有页面均已缓存，直接切换
       console.log('[handlePageChange] 无需加载，直接切换', {
         currentPage,
         newPage,
-        preloadRange,
-        missingPages,
         reason: '所有页面均已缓存'
       });
+
       setCurrentPage(newPage);
     } else {
-      // 理论上不应该到这里（missingPages.length > 0 但 hasMore=false）
+      // 场景D: 意外分支（有缺失页面但 hasMore=false）
       console.warn('[handlePageChange] 意外分支：有缺失页面但无法加载', {
         missingPages,
         hasMore,
@@ -263,7 +302,6 @@ const usePagination = ({ allCachedEvents, total, cachedCount, dispatch, toast })
         cachedCount
       });
 
-      // 尝试切换页码，但可能会显示空数据
       setCurrentPage(newPage);
 
       toast({
@@ -275,7 +313,20 @@ const usePagination = ({ allCachedEvents, total, cachedCount, dispatch, toast })
         position: 'top'
       });
     }
-  }, [currentPage, allCachedEvents, pageSize, totalPages, hasMore, dispatch, total, toast, cachedCount]);
+  }, [
+    currentPage,
+    pageSize,
+    totalPages,
+    hasMore,
+    total,
+    allCachedEvents.length,
+    cachedCount,
+    checkTargetPageCache,
+    calculatePreloadRange,
+    findMissingPages,
+    loadPages,
+    toast
+  ]);
 
   // 模式切换处理
   const handleModeToggle = useCallback((newMode) => {