var currentSlide = 1;
var stepWidth = 946;
var totalSlides;
var isAnimated = false;
var slideSpeed = 1000;

$(document).ready(function(){

    totalSlides = $('#slider li').size();

    $('#slider li:last').clone().prependTo('#slider');

    $('#prev, #previe7').click(function(){
        if ( isAnimated ) return;
        isAnimated = true;
        var currentMargin = $('#slider').css('margin-left');
        currentMargin = parseInt( currentMargin.replace('px', '') );
        newMargin = currentMargin + stepWidth;
        $('#slider').animate({'margin-left':newMargin+'px'}, slideSpeed, function(){
            if ( currentSlide == 0 ){
                fullMargin = parseInt(totalSlides * stepWidth);
                $('#slider').css({'margin-left' : '-'+fullMargin+'px'});
                currentSlide = totalSlides;
            }
            isAnimated = false;
        });
        currentSlide--;
    });




    $('#next').click(function(){
        if ( isAnimated ) return;
        isAnimated = true;
        if ( currentSlide == totalSlides ){
                 $('#slider').css({'margin-left':'0px'});
                currentSlide = 0;  
        }
        var currentMargin = $('#slider').css('margin-left');
        currentMargin = parseInt( currentMargin.replace('px', '') );
        newMargin = currentMargin - stepWidth;
        $('#slider').animate({'margin-left':newMargin+'px'}, slideSpeed, function(){
            isAnimated = false;
        });
        currentSlide++;
    });


});