var wk_num = 0;
var wk_max = 2;
var file_type = '.jpg';
var time = 7500;
var intervalID;

chg_marker();
$('#mainimg img.prev').click(arrow_prev);
$('#mainimg img.next').click(arrow_next);
intervalID = setInterval(arrow_next, time);

function arrow_prev(e){
	wk_num--;
	if(wk_num<0)wk_num=wk_max;
	chg_works();
	chg_marker();
	opacity_animete();
	clearInterval(intervalID);
	intervalID = setInterval(arrow_next, time);
}

function arrow_next(e){
	wk_num++;
	if(wk_num>wk_max)wk_num=0;
	chg_works();
	chg_marker();
	opacity_animete();
	clearInterval(intervalID);
	intervalID = setInterval(arrow_next, time);
}

function chg_works(){
	$('#mainimg img.main').attr('src', '/contents/images/top/mainimg'+wk_num+file_type);
}

function click_chg(num){
	wk_num = num;
	$('#mainimg img.main').attr('src', '/contents/images/top/mainimg'+wk_num+file_type);
	chg_marker();
	opacity_animete();
	clearInterval(intervalID);
	intervalID = setInterval(arrow_next, time);
}

function chg_marker(){
	for(var i=0; i<3; i++){
		$('#mainimg img.bar'+i).attr('src', '/contents/images/top/marker_off_top.gif');
	}
	$('#mainimg img.bar'+wk_num).attr('src', '/contents/images/top/marker_on_top.gif');
}

function opacity_animete(){
	$('#mainimg img.main')
		.stop()
		.css('opacity', 0)
		.animate({
			opacity : 1
		}, 2000);
}