import { NotificationCenter} from 'Foundation';
import { UIApplication } from "UIKit"
import { OnUserCaptureScreen, OffUserCaptureScreen, UserCaptureScreenCallback } from "../interface.uts"


/**
 * 定义监听截屏事件工具类
 */
class CaptureScreenTool {
	static listener: UserCaptureScreenCallback | null;
	
	// 监听截屏
	static listenCaptureScreen(callback: UserCaptureScreenCallback | null) {
		this.listener = callback
		
		// 注册监听截屏事件及回调方法
		// target-action 回调方法需要通过 Selector("方法名") 构建
		const method = Selector("userDidTakeScreenshot")
		NotificationCenter.default.addObserver(this, selector = method, name = UIApplication.userDidTakeScreenshotNotification, object = null)
	}
	
	// 捕获截屏回调的方法
	// target-action 的方法前需要添加 @objc 前缀
	@objc static userDidTakeScreenshot() {
		// 回调
		this.listener?.({})
	}
	
	// 移除监听事件
	static removeListen(callback: UserCaptureScreenCallback | null) {
		this.listener = null
		NotificationCenter.default.removeObserver(this)
	}
}

// /**
//  * 开启截图监听
//  */
// export function onUserCaptureScreen(callback?: UTSCallback) {
// 	CaptureScreenTool.listenCaptureScreen(callback)
// }

// /**
//  * 关闭截屏监听
//  */
// export function offUserCaptureScreen(callback?: UTSCallback) {
// 	CaptureScreenTool.removeListen(callback)
// }

/**
	* 开启截图监听
	*/
export const onUserCaptureScreen : OnUserCaptureScreen = function (callback : UserCaptureScreenCallback | null) {
	CaptureScreenTool.listenCaptureScreen(callback)
}

/**
	* 关闭截屏监听
	*/
export const offUserCaptureScreen : OffUserCaptureScreen = function (callback : UserCaptureScreenCallback | null) {
	CaptureScreenTool.removeListen(callback)
}