var slider = function( idName ){
	this.timer;
	this.idName = "#" + idName;
	this.imageWidth = $( this.idName + ' .sliderInner .image1' ).width();
	this.imageNumber = 2;
	this._init();
};
slider.prototype._init = function(){
	var sliderSize = $( this.idName + ' .sliderInner' ).children().size(),
		imageWidth = this.imageWidth,
		sliderWidth = sliderSize * imageWidth, 
		i = 1;
	$( this.idName + ' .sliderInner' ).css( "width", sliderWidth );	
	$( this.idName + ' .sliderInner' ).children().each(	
		function(){	
			$( this ).css( 'position', 'absolute' );						
			$( this ).css( 'top', 0 );						
			if (i != 1) {
				$( this ).css( 'left', imageWidth );						
				$(this).css('z-index', 1);
			}else{
				$(this).css('z-index', 0);
			}		
			i++;
		}
	);
	this._timer();
};
slider.prototype._timer = function(){
	var obj = this;
	this.timer = setTimeout( function(){ obj.changeImageSlide(); }, 4000 );  
};
slider.prototype.changeImageSlide = function(){
	var imageWidth = this.imageWidth,
		i= this.imageNumber,
		sliderSize = $( this.idName + ' .sliderInner' ).children().size(),
		obj = this; 
	$( this.idName + ' .sliderInner .image' + i ).animate(
		{ left: '-=' + imageWidth },
		3000,
		function(){						 
			var minus;			
			if( i == 1 ){
				minus = sliderSize;
			}else{
				minus = i - 1;
			}			 			
			$( obj.idName + ' .sliderInner .image' + minus ).css( "left", imageWidth + 'px' );
			$( obj.idName + ' .sliderInner .image' + minus ).css( "z-index", 1 );
			$( obj.idName + ' .sliderInner .image' + i ).css( "z-index", 0 );
			if( i == sliderSize ){
				obj.imageNumber = 1;
			}else{
				obj.imageNumber++;
			}			
			obj._timer();
		}
	);
};
slider.prototype.forceSlide = function( direction ){
	clearTimeout( this.timer );
	var i = this.imageNumber;

	$( this.idName + ' .sliderInner .image' + i ).animate(
	{}, 
	3000, 
	function(){
		$( obj.idName + ' .sliderInner .image' + minus ).css( "left", imageWidth + 'px' );
		$( obj.idName + ' .sliderInner .image' + minus ).css( "z-index", 1 );
		$( obj.idName + ' .sliderInner .image' + i ).css( "z-index", 0 );
		if( i == sliderSize ){
			obj.imageNumber = 1;
		}else{
			obj.imageNumber++;
		}			
		obj._timer();
	});
};