function validEmail(email) {
    var regex = /\w+@[a-zA-Z_]+?\.[a-zA-Z]{2,6}/;
    return regex.test(email);
}
function validSerialNumber(serial) {
    return (serial.length >= 6);
}

function replaceMollom(format) {
    if (format!="audio") format = "image";
    $.ajax({
      url: "/global/ajax_mollom.php?format="+format,
      success: function(r){
        if (format == 'audio') format = 'image';
        else format = 'audio';
        r += ' (<a href="javascript:replaceMollom(\''+format+'\')">verify using '+format+'</a>)';
        $("#mollom").html(r);
        if (format == 'image') $("#mollom_desc").html("Please listen to the audio clip below and type the characters that you hear.");
        else $("#mollom_desc").html("Type the characters you see in the picture below. Having difficulty reading the characters? <a href=\"javascript:replaceMollom('image')\">Refresh</a> the image.");
      }
    });
}

$(document).ready(function() {
    $("#tradeinform").submit( function() {
        var msg = new Array;
        $(".required").removeClass("missing_required"); //clean up from last submit
        $(".required[value=]").addClass("missing_required");
        if ($(".required[value=]").length>0) { 
            msg.push("Please fill out all required fields.");
        };
        if ($("#email").val()!='' && !validEmail($("#email").val())) {
              msg.push("Please enter a valid email."); 
              $("#email").addClass("missing_required");
        }
        //require either serial or info fields
        if ($(".info[value=]").length>0 ){
            if ($('#serial').val()=='') {
                //serial is blank so require other info
                $(".info[value=]").addClass("missing_required");
                msg.push("We need more information to work with.  Please either enter the serial number of your Mac, OR its model, screen size and processor speed.");
            } 
            //validate serial
            else if (!validSerialNumber($("#serial").val())) {
                $("#serial").addClass("missing_required");
                msg.push("The serial number that you have entered is not valid. Please either enter the serial number of your Mac, OR its model, screen size and processor speed.");
            }
        }
        
        //require mollom
        if ($("#mollom_text").val() == '') {
            $("#mollom_text").addClass("missing_required");
            msg.push("Please fill out the CAPTCHA code at the bottom of this page so that we know you are not a spam bot.");
        }
        if (msg.length > 0) {
            alert("There are one or more problems with your submission: \n\n"+msg.join("\n\n"));
            return false;  
        }
        return true;
    });
});