refactor: 使用indexeddb替代localStorage解决safari配额限制

Author: Hronrad

src/utils/webdav.ts

@@ -1,4 +1,4 @@
-// WebDAV 同步工具
+// WebDAV 同步工具（使用 IndexedDB 解决 Safari 配额限制）
 interface WebDAVConfig {
   url: string
   username: string
@@ -7,6 +7,9 @@ interface WebDAVConfig {
 
 const WEBDAV_CONFIG_KEY = 'webdav_config'
 const WEBDAV_FILE_NAME = 'chatgpt-backup.json'
+const DB_NAME = 'ChatStorage'
+const DB_VERSION = 1
+const STORE_NAME = 'data'
 
 export function getWebDAVConfig(): WebDAVConfig | null {
   const config = localStorage.getItem(WEBDAV_CONFIG_KEY)
@@ -17,6 +20,67 @@ export function saveWebDAVConfig(config: WebDAVConfig): void {
   localStorage.setItem(WEBDAV_CONFIG_KEY, JSON.stringify(config))
 }
 
+// IndexedDB 操作
+function openDB(): Promise<IDBDatabase> {
+  return new Promise((resolve, reject) => {
+    const request = indexedDB.open(DB_NAME, DB_VERSION)
+    request.onerror = () => reject(request.error)
+    request.onupgradeneeded = (event: any) => {
+      const db = event.target.result
+      if (!db.objectStoreNames.contains(STORE_NAME))
+        db.createObjectStore(STORE_NAME)
+    }
+    request.onsuccess = () => resolve(request.result)
+  })
+}
+
+async function saveToStorage(data: string): Promise<void> {
+  // 优先使用 IndexedDB（配额更大，Safari 友好）
+  try {
+    const db = await openDB()
+    const tx = db.transaction(STORE_NAME, 'readwrite')
+    const store = tx.objectStore(STORE_NAME)
+    await new Promise<void>((resolve, reject) => {
+      const req = store.put(data, 'chatStorage')
+      req.onsuccess = () => resolve()
+      req.onerror = () => reject(req.error)
+    })
+    db.close()
+    
+    // 同步到 localStorage（兼容现有代码读取）
+    try {
+      localStorage.setItem('chatStorage', data)
+    }
+    catch {
+      // localStorage 失败不影响，数据已保存到 IndexedDB
+    }
+  }
+  catch (error) {
+    // IndexedDB 失败，降级到 localStorage
+    localStorage.setItem('chatStorage', data)
+  }
+}
+
+async function loadFromStorage(): Promise<string> {
+  // 优先从 IndexedDB 读取
+  try {
+    const db = await openDB()
+    const tx = db.transaction(STORE_NAME, 'readonly')
+    const store = tx.objectStore(STORE_NAME)
+    const data = await new Promise<string>((resolve, reject) => {
+      const req = store.get('chatStorage')
+      req.onsuccess = () => resolve(req.result || '{}')
+      req.onerror = () => reject(req.error)
+    })
+    db.close()
+    return data
+  }
+  catch {
+    // IndexedDB 失败，降级到 localStorage
+    return localStorage.getItem('chatStorage') || '{}'
+  }
+}
+
 async function webdavRequest(config: WebDAVConfig, method: string, data?: string) {
   const url = `${config.url.replace(/\/$/, '')}/${WEBDAV_FILE_NAME}`
   const res = await fetch('/api/webdav-proxy', {
@@ -34,10 +98,9 @@ export async function syncToWebDAV(): Promise<void> {
   const config = getWebDAVConfig()
   if (!config)
     throw new Error('WebDAV 未配置')
-  
-  const data = localStorage.getItem('chatStorage') || '{}'
-  
-  // 尝试上传，如果失败尝试创建目录再上传
+
+  const data = await loadFromStorage()
+
   try {
     await webdavRequest(config, 'PUT', data)
   }
@@ -65,7 +128,7 @@ export async function syncFromWebDAV(): Promise<void> {
   const config = getWebDAVConfig()
   if (!config)
     throw new Error('WebDAV 未配置')
-  
+
   const result = await webdavRequest(config, 'GET')
-  localStorage.setItem('chatStorage', result.data || '{}')
+  await saveToStorage(result.data || '{}')
 }