const KeyValueDB = {
	dbName: 'kvStorage',
	storeName: 'kvStore',
	
	async init() {
	  return new Promise((resolve) => {
		const request = indexedDB.open(this.dbName, 1);
		
		request.onupgradeneeded = (e) => {
		  const db = e.target.result;
		  if (!db.objectStoreNames.contains(this.storeName)) {
			db.createObjectStore(this.storeName);
		  }
		};
		
		request.onsuccess = () => resolve(request.result);
	  });
	},
  
	// 设置值（类似 localStorage.setItem）
	async set(key, value) {
	  const db = await this.init();
	  return new Promise((resolve) => {
		const tx = db.transaction(this.storeName, 'readwrite');
		tx.objectStore(this.storeName).put(value, key);
		tx.oncomplete = () => resolve();
	  });
	},
  
	// 获取值（类似 localStorage.getItem）
	async get(key) {
	  const db = await this.init();
	  return new Promise((resolve) => {
		const tx = db.transaction(this.storeName, 'readonly');
		const request = tx.objectStore(this.storeName).get(key);
		request.onsuccess = () => resolve(request.result);
	  });
	},
  
	// 删除值
	async remove(key) {
	  const db = await this.init();
	  return new Promise((resolve) => {
		const tx = db.transaction(this.storeName, 'readwrite');
		tx.objectStore(this.storeName).delete(key);
		tx.oncomplete = () => resolve();
	  });
	},
  
	// 清空所有
	async clear() {
	  const db = await this.init();
	  return new Promise((resolve) => {
		const tx = db.transaction(this.storeName, 'readwrite');
		tx.objectStore(this.storeName).clear();
		tx.oncomplete = () => resolve();
	  });
	},
  
	// 获取所有键
	async keys() {
	  const db = await this.init();
	  return new Promise((resolve) => {
		const tx = db.transaction(this.storeName, 'readonly');
		const store = tx.objectStore(this.storeName);
		const request = store.getAllKeys();
		request.onsuccess = () => resolve(request.result);
	  });
	}
  };
  export {KeyValueDB}