var js_rolling = function(this_s){
	// 시간단위는 ms로 1000이 1초

	if(this_s.nodeType==1){
		this.this_s = this_s;
	}else{
		this.this_s = document.getElementById(this_s);
	}
	this.is_rolling = false;
	this.direction = 4; //1:top, 2:right, 3:bottom, 4:left (시계방향) // 1번과 4번만 됨

	this.children =	null;
	this.move_gap = 1;	//움직이는 픽셀단위
	this.time_dealy = 100; //움직이는 타임딜레이
	this.time_dealy_pause = 1000;//하나의 대상이 새로 시작할 때 멈추는 시간, 0 이면 적용 안함
	this.time_timer=null;
	this.time_timer_pause=null;
	this.set_direction(this.direction);
	this.init_event();

	this.first_item = this.this_s.firstChild;
	this.last_item = this.this_s.lastChild;
	this.mid_item = this.this_s.children[ this.this_s.children.lengt-8];	// 한라인에 8개가 동시에 보여진다는 가정을 깔고 있으므로 보여지는 책표지의 width또는 Newbook_list의 width가 바뀐다면 더이상 8이 아닐수도 있음.
}
js_rolling.prototype.set_direction = function(direction){
	this.direction=direction;
	this.get_element_children();
}
js_rolling.prototype.init_event = function(){
	var this_s=this;
	this.this_s.onmouseover=function(){
		if(!this_s.time_timer_pause){
			this_s.pause();
		}
	}
	this.this_s.onmouseout=function(){
		if(!this_s.time_timer_pause){
			this_s.resume();
		}
	}	
}
js_rolling.prototype.get_element_children = function(){
	this.this_s.style.position='relative';
	this.this_s.style.overflow='hidden';
	var children = this.this_s.childNodes;
	this.children = children;
	for(var i=(children.length-1);0<=i;i--){
		if(children[i].nodeType==1){
			children[i].style.position='relative';
			if(this.direction==1){
				children[i].style.top='0px';
			}else if(this.direction==4){
				children[i].style.left='0px';				
				this.this_s.style.whiteSpace='nowrap';										
			}
		}else{
			this.this_s.removeChild(children[i]);
		}
	}
}
js_rolling.prototype.act_move_up = function(){
	for(var i = 0,m=this.children.length;i<m;i++){
		var child = this.children[i];
		child.style.top=(parseInt(child.style.top)-this.move_gap)+'px';
	}
	if((this.children[0].offsetHeight+parseInt(this.children[0].style.top))<=0){
		this.this_s.appendChild(this.children[0]);
		this.get_element_children();
		if(this.time_dealy_pause){
			var this_s = this;
			var act = function(){this_s.resume();this_s.time_timer_pause=null;}
			this.time_timer_pause = setTimeout(act,this.time_dealy_pause);
			this.pause();
		}		
	}
}
js_rolling.prototype.act_move_left = function(){
	for(var i = 0,m=this.children.length;i<m;i++){
		var child = this.children[i];
		child.style.left=(parseInt(child.style.left)-this.move_gap)+'px';
	}
	if((this.children[0].offsetWidth+parseInt(this.children[0].style.left))<=0){
		this.this_s.appendChild(this.this_s.firstChild);
		this.get_element_children();
		if(this.time_dealy_pause){
			var this_s = this;
			var act = function(){this_s.resume();this_s.time_timer_pause=null;}
			this.time_timer_pause = setTimeout(act,this.time_dealy_pause);
			this.pause();
		}				
	}
}

js_rolling.prototype.start = function(){ //롤링 시작
	var this_s = this;
	this.stop();
	this.is_rolling = true;
	var act = function(){
		if(this_s.is_rolling){
			if(this_s.direction==1){this_s.act_move_up();}
			else if(this_s.direction==4){this_s.act_move_left();}
		}
	}
	this.time_timer = setInterval(act,this.time_dealy);
}

js_rolling.prototype.pause = function(){ //일시 멈춤
	this.is_rolling = false;
}
js_rolling.prototype.resume = function(){ //일시 멈춤 해제
	this.is_rolling = true;
}
js_rolling.prototype.stop = function(){ //롤링을 끝냄
	this.is_rolling = false;
	if(!this.time_timer){
		clearInterval(this.time_timer);
	}
	this.time_timer = null
}



// 책 한권 너비만큼 왼쪽으로 이동 2010.08.17 
js_rolling.prototype.act_move_book_left = function(){

	while (this.children[0].offsetWidth+parseInt(this.children[0].style.left)>0)
	{
		for(var i = 0,m=this.children.length;i<m;i++){
			var child = this.children[i];
			child.style.left=(parseInt(child.style.left)-this.move_gap)+'px';
		}
	}


	this.this_s.appendChild(this.this_s.firstChild);
	this.get_element_children();
	if(this.time_dealy_pause){
		var this_s = this;
		var act = function(){this_s.resume();this_s.time_timer_pause=null;}
		this.time_timer_pause = setTimeout(act,this.time_dealy_pause);
		this.pause();
	}
}

// 책 한권 너비만큼 오른쪽으로 이동 2010.08.17 
js_rolling.prototype.act_move_book_right = function()
{

	while (parseInt(this.children[0].style.left)<0)
	{
		for(var i = 0,m=this.children.length;i<m;i++){
			var child = this.children[i];
			child.style.left=(parseInt(child.style.left)+this.move_gap)+'px';
		}
	}

	// 무식한 방법
	for ( var i=0, m=this.children.length; i<m-1; i++ ) {
		this.this_s.appendChild(this.this_s.firstChild);		
	}

	this.get_element_children();
	if(this.time_dealy_pause){
		var this_s = this;
		var act = function(){this_s.resume();this_s.time_timer_pause=null;}
		this.time_timer_pause = setTimeout(act,this.time_dealy_pause);
		this.pause();
	}
}


// 책 리스트의 첫번째로 이동 2010.08.17 
js_rolling.prototype.act_move_book_first = function(){

	// 요즘 컴퓨터 속도로는 금방이다.
	while (parseInt(this.children[0].style.left) > 0)
	{
		for(var i = 0,m=this.children.length;i<m;i++){
			var child = this.children[i];
			child.style.left=(parseInt(child.style.left)-10)+'px';
		}
	}

	while ( this.this_s.firstChild != this.first_item )
	{
		this.this_s.appendChild(this.this_s.firstChild);
	}

	this.get_element_children();
	if(this.time_dealy_pause){
		var this_s = this;
		var act = function(){this_s.resume();this_s.time_timer_pause=null;}
		this.time_timer_pause = setTimeout(act,this.time_dealy_pause);
		this.pause();
	}
}


// 책 리스트의 마지막으로 이동 2010.08.17 
js_rolling.prototype.act_move_book_last = function()
{
	while ( this.this_s.firstChild != this.last_item ) {
		this.this_s.appendChild(this.this_s.firstChild);		
	}
	this.get_element_children();
	if(this.time_dealy_pause){
		var this_s = this;
		var act = function(){this_s.resume();this_s.time_timer_pause=null;}
		this.time_timer_pause = setTimeout(act,this.time_dealy_pause);
		this.pause();
	}
	/*수정전 2010.08.17
	while ( this.this_s.lastChild != this.mid_item )
	{
		this.this_s.appendChild(this.this_s.firstChild);
	}

	this.get_element_children();
	if(this.time_dealy_pause){
		var this_s = this;
		var act = function(){this_s.resume();this_s.time_timer_pause=null;}
		this.time_timer_pause = setTimeout(act,this.time_dealy_pause);
		this.pause();
	}
	*/
}