修复内存溢出问题

src/services/cacheService.ts

@@ -3,6 +3,10 @@ import { Project, Generation, Asset } from '../types';
 
 const CACHE_PREFIX = 'nano-banana';
 const CACHE_VERSION = '1.0';
+// 限制缓存项目数量
+const MAX_CACHED_ITEMS = 50;
+// 限制缓存最大年龄 (3天)
+const MAX_CACHE_AGE = 3 * 24 * 60 * 60 * 1000;
 
 export class CacheService {
   private static getKey(type: string, id: string): string {
@@ -11,6 +15,8 @@ export class CacheService {
 
   // Project caching
   static async saveProject(project: Project): Promise<void> {
+    // 在保存新项目之前，清理旧缓存
+    await this.clearOldCache();
     await set(this.getKey('project', project.id), project);
   }
 
@@ -33,6 +39,8 @@ export class CacheService {
 
   // Asset caching (for offline access)
   static async cacheAsset(asset: Asset, data: Blob): Promise<void> {
+    // 在保存新资产之前，清理旧缓存
+    await this.clearOldCache();
     await set(this.getKey('asset', asset.id), {
       asset,
       data,
@@ -47,6 +55,8 @@ export class CacheService {
 
   // Generation metadata caching
   static async cacheGeneration(generation: Generation): Promise<void> {
+    // 在保存新生成记录之前，清理旧缓存
+    await this.clearOldCache();
     await set(this.getKey('generation', generation.id), generation);
   }
 
@@ -55,17 +65,55 @@ export class CacheService {
   }
 
   // Clear old cache entries
-  static async clearOldCache(maxAge: number = 7 * 24 * 60 * 60 * 1000): Promise<void> {
+  static async clearOldCache(maxAge: number = MAX_CACHE_AGE): Promise<void> {
     const allKeys = await keys();
     const now = Date.now();
     
+    // 收集需要删除的键
+    const keysToDelete: string[] = [];
+    const validCachedItems: Array<{key: string, cachedAt: number}> = [];
+    
     for (const key of allKeys) {
       if (typeof key === 'string' && key.startsWith(CACHE_PREFIX)) {
         const cached = await get(key);
-        if (cached?.cachedAt && (now - cached.cachedAt) > maxAge) {
-          await del(key);
+        if (cached?.cachedAt) {
+          // 检查是否过期
+          if ((now - cached.cachedAt) > maxAge) {
+            keysToDelete.push(key);
+          } else {
+            validCachedItems.push({key, cachedAt: cached.cachedAt});
+          }
         }
       }
     }
+    
+    // 如果有效项目数量超过限制，删除最旧的项目
+    if (validCachedItems.length > MAX_CACHED_ITEMS) {
+      // 按时间排序，最旧的在前面
+      validCachedItems.sort((a, b) => a.cachedAt - b.cachedAt);
+      // 计算需要删除的数量
+      const excessCount = validCachedItems.length - MAX_CACHED_ITEMS;
+      // 添加最旧的项目到删除列表
+      for (let i = 0; i < excessCount; i++) {
+        keysToDelete.push(validCachedItems[i].key);
+      }
+    }
+    
+    // 执行删除
+    for (const key of keysToDelete) {
+      await del(key);
+    }
+  }
+  
+  // 清空所有缓存
+  static async clearAllCache(): Promise<void> {
+    const allKeys = await keys();
+    const cacheKeys = allKeys.filter(key => 
+      typeof key === 'string' && key.startsWith(CACHE_PREFIX)
+    );
+    
+    for (const key of cacheKeys) {
+      await del(key);
+    }
   }
 }