مساعده - محاولة شرح الكود التالي - مهم جدا

السلام عليكم و رحمة الله و بركاته

تحية طيبة لكم احبتي الكرام، ارجو المساعدة للاهمية القصوى و لكم الاجر و الثواب ان شاء الله

احتاج لشرح هذا الكود خطوة بخطوة مع الاسهاب بالشرح 

الكود هو : 

function VideoShift()
 {
	"use strict";
	
	var self = Ti.UI.createView({navBarHidden:true}), myNum = 0, timer=null, click1=null, click2=null, videoPlayer, myButtonChoice1a, myButtonChoice1b, image;

	function setupNowButtonsChoice1()
	{
		
		function removeButtons()
		{
			Ti.API.info('remove two buttons: ');
			myButtonChoice1a.removeEventListener('click', click1Function);
			myButtonChoice1a.hide();
			myButtonChoice1a = null;
			myButtonChoice1b.removeEventListener('click', click2Function);
			myButtonChoice1b.hide();
			myButtonChoice1b = null;
		}
		myButtonChoice1a = Ti.UI.createButton({
			title: 'Kvinden',
			color: 'faec06' ,
			font: { fontSize:24 },
			top: 200,
			width: 400,
			height: 100
		});
		function click1Function(e){
		videoPlayer.setCurrentPlaybackTime(33000.50000);
			videoPlayer.play();
			removeButtons();			
		}
		
		function click2Function(e){
			videoPlayer.setCurrentPlaybackTime(16500.33000);
			videoPlayer.play();
			removeButtons();
		}
			
		click1 = myButtonChoice1a.addEventListener('click',click1Function);
		
		myButtonChoice1b = Ti.UI.createButton({
			title: 'Manden',
			color: 'faec06' ,
			font: { fontSize:24 },
			top: 250,
			width: 400,
			height: 100
		});
		click2 = myButtonChoice1b.addEventListener('click',click2Function);
		
		self.add(myButtonChoice1a);
		self.add(myButtonChoice1b);
	}
		
	image = Ti.UI.createImageView({
	  image:'myimage1.png',
	  top : 70,
	  width: 100,
	  height : 50
	});
	self.add(image);

	videoPlayer = Titanium.Media.createVideoPlayer({
	    top : 50,
	    autoplay : false,
	    backgroundColor : 'transparent',
	    height : 300,
	    width : 300,
	    mediaControlStyle : Titanium.Media.VIDEO_CONTROL_DEFAULT,
	    scalingMode : Titanium.Media.VIDEO_SCALING_ASPECT_FIT
	});
	
	function loadChoice1()
	{
		Ti.API.info("now setup buttons");
		setupNowButtonsChoice1();
	}
	
	function setupChoice1(inParam) {
		switch (inParam.choice) {
			case 'choice1' :
				loadChoice1();
				break;
			default :
				break;
		}
	}
	
	function doTiming() {
		Ti.API.info('timer is running: ');
		Ti.API.info('Time: '+videoPlayer.currentPlaybackTime);
		var time1 = videoPlayer.currentPlaybackTime;
		if ((time1 > 15000) && (time1 < 15700) )
		{
			clearInterval(timer);

			videoPlayer.pause(); 
			Ti.App.fireEvent('VideoChoice1', {choice: 'choice1'});
		}
		if (time1 >= videoPlayer.duration){
			clearInterval(timer);
		}
		
	}
	videoPlayer.addEventListener('playbackState', function(e) {
		Ti.API.info('state is changing');
		if (myNum===0){
			myNum=1;
			timer = setInterval(doTiming,250);
			Ti.API.info("Video starting: "+e);
		}else {
			Ti.API.info("Video stopping: "+e);
			myNum = 0;
			clearInterval(timer);
		}		
	});
	
	videoPlayer.url = 'localhost/samlet.mp4';
	
	self.add(videoPlayer);
	
	Ti.App.addEventListener('VideoChoice1', setupChoice1);
	
	return self;
}

module.exports = VideoShift;