$(document).ready(function() {

// add form submit button
$("form").append('<p>Total: $<strong id="total">90</strong></p> \
<p><input type="image" src="https://www.paypal.com/en_US/i/btn/btn_buynow_LG.gif" id="submit" name="submit" alt="Buy Now"></p> \
');

// set defaults
$("input").attr("disabled","");
$("#frireg").attr("checked","checked");
$("#satreg").attr("checked","checked");
$("#sunreg").attr("checked","checked");
$("#nocomp").attr("checked","checked");
$("#quartet").attr("checked","");
$("#maetix").attr("value","0");
$("#studenttix").attr("value","0");
$("#amount").attr("value","90");
$("#total").text("93");
var reg=90;
var comp=0;
var quar=0;
var tix=0;
var studenttix=0;
var days=7;

$("input").click( function (){
    formchange();
});


$("#maetix").keyup( function (){
    formchange();
});

$("#studenttix").keyup( function (){
    formchange();
});

function enablecomps() {
    $("#quartet").attr("disabled","");
    $("#quartet + label").css("color","black");
    $("#colsolo").attr("disabled","");
    $("#colsolo + label").css("color","black");
    $("#highaud").attr("disabled","");
    $("#highaud + label").css("color","black");
    $("#lowaud").attr("disabled","");
    $("#lowaud + label").css("color","black");
}

function enablehs() {
    $("#hssolo").attr("disabled","");
    $("#hssolo + label").css("color","black");
}

function disablecomps() {
    if (!($("#hssolo").attr("checked"))) $("#nocomp").attr("checked","checked");
    $("#quartet").attr("checked","");
    $("#quartet").attr("disabled","disabled");
    $("#quartet + label").css("color","gray");
    $("#colsolo").attr("disabled","disabled");
    $("#colsolo + label").css("color","gray");
    $("#highaud").attr("disabled","disabled");
    $("#highaud + label").css("color","gray");
    $("#lowaud").attr("disabled","disabled");
    $("#lowaud + label").css("color","gray");
}

function disablehs() {
    $("#nocomp").attr("checked","checked");
    $("#hssolo").attr("disabled","disabled");
    $("#hssolo + label").css("color","gray");
}

function formchange() {

    days=0;
    $("#submit").attr("disabled","");
    if ($("#frireg").attr("checked")) days=days+1;
    if ($("#satreg").attr("checked")) days=days+2;
    if ($("#sunreg").attr("checked")) days=days+4;

    if (days==7) {
        reg=90;
        $("#days").attr("value","Fri/Sat/Sun ($90)");
        enablecomps();
        enablehs();
  } else if (days==6) {
        reg=80;
        $("#days").attr("value","Sat/Sun ($80)");
        disablecomps();
        enablehs();
  } else if (days==5) {
        reg=80;
        $("#days").attr("value","Fri/Sun ($80)");
        disablecomps();
        disablehs();
  } else if (days==3) {
        reg=80;
        $("#days").attr("value","Fri/Sat ($80)");
        enablecomps();
        enablehs();
  } else if (days==4) {
        reg=45;
        $("#days").attr("value","Sun ($45)");
        disablecomps();
        disablehs();
  } else if (days==2) {
        reg=45;
        $("#days").attr("value","Sat ($45)");
        disablecomps();
        enablehs();
  } else if (days==1) {
        reg=45;
        $("#days").attr("value","Fri ($45)");
        disablecomps();
        disablehs();
  } else {
        reg=0;
        $("#days").attr("value","No Workshop Registration ($0)");
        disablecomps();
        disablehs();
  }

    if ($("#nocomp").attr("checked")) comp=0
      else comp=5;
    if ($("#quartet").attr("checked")) {
        quar=5;
        $("#quartetlabel").attr("value","yes ($5)");
  } else {
        quar=0;
        $("#quartetlabel").attr("value","no");
  }
    tix = $("#maetix").attr("value") *25;
    studenttix = $("#studenttix").attr("value") *15;
    if ($("#maetix").attr("value") == "") tix=0;
    if ($("#studenttix").attr("value") == "") studenttix=0;
    var grandtotal = reg + comp + quar + tix + studenttix;
    if (grandtotal==0) $("#submit").attr("disabled","disabled");
    $("#amount").attr("value",grandtotal);
    $("#total").text(grandtotal+3);
}

});