var calcLicensePrice = function(num){
    if(!num || num < 1 || num > 50) return false;
    var price = 0;
    for(var i = 1; i <= num; i++){
        if(i <= 1){
            price += 25;
        } else if(i <= 4) {
            price += 20;
        } else if(i <= 20) {
            price += 17;
        } else {
            price += 15;
        }
    }
    return price;
}

var displayPrice = function(){
    var c = jQuery("input#licenseCounter").val();
    c = c.replace(/[^0-9]/g,"");
    jQuery("input#licenseCounter").val(c);
    var p = calcLicensePrice(c);
    if(p){
        var userstr = (c==1) ? "user" : "users";
        jQuery("span#counterResult").text(p + " EUR / " + c + " " + userstr);
        jQuery("input#licenseSubmit").attr("disabled", "");
    } else {
        errorStr = (null !== c && c > 50) ? "<i>Please contact our sales representative at sales@tuxera.com.</i>" : "<i>Please enter a number between 1 and 50.</i>";
        jQuery("span#counterResult").html(errorStr);
        jQuery("input#licenseSubmit").attr("disabled", "disabled");
    }
}

jQuery("input#licenseCounter").blur(displayPrice);
jQuery(document).ready(displayPrice);