export class MethodLocker<R> {
	private isLocked: boolean = false;
	private queue: Array<() => Promise<any>> = [];

	/**
	 * 执行被锁定的方法
	 * @param task 需要执行的任务，返回一个 Promise
	 */
	async execute(task: () => Promise<R>): Promise<R> {
		// 如果当前没有被锁定，直接执行任务
		if (!this.isLocked) {
			this.isLocked = true;
			try {
				return await task();
			} finally {
				this.isLocked = false;
				await this.dequeue();
			}
		} else {
			// 如果被锁定，将任务加入队列并等待
			return new Promise<R>((resolve, reject) => {
				this.queue.push(async () => {
					try {
						const result = await task();
						resolve(result);
					} catch (error) {
						reject(error);
					} finally {
						this.dequeue();
					}
				});
			});
		}
	}

	/**
	 * 处理队列中的下一个任务
	 */
	private dequeue(): Promise<R> | undefined {
		if (this.queue.length > 0) {
			const nextTask = this.queue.shift();
			if (nextTask) {
				return this.execute(nextTask);
			}
		}
		return undefined;
	}
}