var imgNames = new Array();
imgNames[0] = 'home';
imgNames[1] = 'port';
imgNames[2] = 'spec';
imgNames[3] = 'cont';
imgNames[4] = 'font';
imgNames[5] = 'color';
imgNames[6] = 'mats';
imgNames[7] = 'submit';
imgNames[8] = 'est';

for (i in imgNames)
{
	img = new Image();
	img.src = 'images/'+imgNames[i]+'1.png';
	img2 = new Image();
	img2.src = 'images/'+imgNames[i]+'2.png';
}

function swapImg (img)
{
	img.src = (img.src.match('2.')) ? img.src.replace(/2./, '1.') : img.src.replace(/1./,'2.');
}

function verifyForm()
{
    var m = '';
    var e = document.getElementById('errorLabel');
    var emailRegEx = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;

    // Check name
    if (document.getElementById('name').value == '') {
        m += 'Please enter your name.<br />';
    }

    // Check email
    var em = document.getElementById('email');
    if (em.value == '') {
        m += 'Please enter your email address.<br />';
    } else if (! em.value.match(emailRegEx)) {
        m += 'Email address format is invalid.<br />';
    }
    
    // Submit form or show error message
    if (m == '') {
        f = document.getElementById('form1');
        f.submit();
    } else {
        e.innerHTML = m;
        e.style.display = 'block';    
    }
}