function isValidEmail(email) {
	var test = /^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i;
	return test.test(email);
}

function showFriendEmailForm() {
	var form = document.getElementById('friend-email').getElementsByTagName('form')[0];
	form.style.display = 'block';
	form.reset();
	form.elements['email'].focus();
}

function hideFriendEmailForm() {
	document.getElementById('friend-email').getElementsByTagName('form')[0].style.display = 'none';
}

function friendEmailFormSubmit() {
	var form = document.getElementById('friend-email').getElementsByTagName('form')[0];
	if (!isValidEmail(form.elements['email'].value)) {
		alert('Please enter a valid email address for your friend.');
		return false;
	}
	if (!form.elements['sender_name'].value) {
		alert('Please enter your name.');
		return false;
	}
	if (!isValidEmail(form.elements['sender_email'].value)) {
		alert('Please enter a valid email address for yourself.');
		return false;
	}
	form.elements['notabot'].value = '1';
	return true;
}