var SlideWidth = 950;
var SlideSpeed = 0;
var TotalWidth = 2850;

jQuery(document).ready(function($) {
    // set the prev and next buttons display
    SetNavigationDisplay();
});

function CurrentMargin() {
    // get current margin of slider
    var currentMargin = jQuery("#slider-wrapper").css("margin-left");

    // first page load, margin will be auto, we need to change this to 0
    if (currentMargin == "auto") {
        currentMargin = 0;
    }

    // return the current margin to the function as an integer
    return parseInt(currentMargin);
}

function SetNavigationDisplay() {
    // get current margin
    var currentMargin = CurrentMargin();

    // if current margin is at 0, then we are at the beginning, hide previous
    if (currentMargin == 0) {
        //jQuery("#PreviousButton").hide();
    }
    else {
        jQuery("#PreviousButton").show();
    }

    // get wrapper width
    var wrapperWidth = jQuery("#slider-wrapper").width();

    // turn current margin into postive number and calculate if we are at last slide, if so, hide next button
    if ((currentMargin * -1) == (wrapperWidth - SlideWidth)) {
        //jQuery("#NextButton").hide();
    }
    else {
        jQuery("#NextButton").show();
    }
}

function NextSlide() {
    // get the current margin and subtract the slide width
    var newMargin = (CurrentMargin() - SlideWidth) % TotalWidth;

    // slide the wrapper to the left to show the next panel at the set speed. Then set the nav display on completion of animation.
    jQuery("#slider-wrapper").animate({ marginLeft: newMargin }, SlideSpeed, function () { SetNavigationDisplay() });
}

function PreviousSlide() {
    // get the current margin and subtract the slide width
    var newMargin = (CurrentMargin() + SlideWidth - TotalWidth) % TotalWidth;

    // slide the wrapper to the right to show the previous panel at the set speed. Then set the nav display on completion of animation.
    jQuery("#slider-wrapper").animate({ marginLeft: newMargin }, SlideSpeed, function () { SetNavigationDisplay() });
}