jQuery(document).ready(function(){
    if (document.getElementById('prevbutton') === null){
        alert('No Ajax Navigation')
    }else{
        document.getElementById('prevbutton').style.visibility = "hidden";
        eval(FunctionList[0]);
        generateButtons(0);
    }
   
 });

 function NextPrevButton(action){
    var currentCouponId = document.getElementById('current_coupon_id').innerHTML;
    var currentArrayIndex = jQuery.inArray(currentCouponId, IdList);
    var newIndex;

    if (action == "next"){
        newIndex = currentArrayIndex + 1;
    } else if (action == "previous") {
        newIndex = currentArrayIndex - 1;
    } else {
        window.alert("Error, please refresh the page and try again. If the problem persist, please contact the website administrator.");
    }

    eval(FunctionList[newIndex]);
    generateButtons(newIndex);
}

function generateButtons(currentArrayIndex){
    //for next button
    if (currentArrayIndex == (IdList.length - 1)) {
        document.getElementById('nextbutton').style.visibility = "hidden";
    }else{
        document.getElementById('nextbutton').style.visibility = "visible";
        document.getElementById('nextbutton').innerHTML = "Next > " + TitleList[currentArrayIndex+1];

    }

    //for previous button
    if (currentArrayIndex == 0){
        document.getElementById('prevbutton').style.visibility = "hidden";
    }else{
        document.getElementById('prevbutton').style.visibility = "visible";
        document.getElementById('nextbutton').innerHTML = "Next > " + TitleList[currentArrayIndex+1];
    }
}