var messageDelay = 2000; // How long to display status messages (in milliseconds)

// Init the form once the document is ready
$(init);

// Initialize the form

function init() {
	// Hide the form initially.
	// Make submitForm() the form's submit handler.
	// Position the form so it sits in the centre of the browser window.
	$('#contactForm').show().on('submit', submitForm).addClass('positioned');

	// When the "Send us an email" link is clicked:
	// 1. Fade the content out
	// 2. Display the form
	// 3. Move focus to the first field
	// 4. Prevent the link being followed

	$('a[href="#contactForm"]').on('click', function () {
		$('#contactForm').fadeTo('slow', 0.2);
		$('#contactForm').fadeIn('slow', function () {
			$('#senderName').focus();
		});

		return false;
	});
}

// Submit the form via Ajax

function submitForm() {
	var contactForm = $(this);

	// Are all the fields filled in?

	if (
		!$('#senderName').val() ||
		!$('#senderEmail').val() ||
		!$('#message').val()
	) {
		// No; display a warning message and return to the form
		$('#incompleteMessage').fadeIn().delay(messageDelay).fadeOut();
		contactForm.fadeOut().delay(messageDelay).fadeIn();
	} else {
		// Yes; submit the form to the PHP script via Ajax

		$('#sendingMessage').fadeIn();
		contactForm.fadeOut();

		$.ajax({
			url: contactForm.attr('action') + '?ajax=true',
			type: contactForm.attr('method'),
			data: contactForm.serialize(),
			success: submitFinished,
		});
	}

	// Prevent the default form submission occurring
	return false;
}

// Handle the Ajax response

function submitFinished(response) {
	response = $.trim(response);
	$('#sendingMessage').fadeOut();

	if (response == 'success') {
		// Form submitted successfully:
		// 1. Display the success message
		// 2. Clear the form fields
		// 3. Fade the content back in

		$('#successMessage').fadeIn().delay(messageDelay).fadeOut();
		$('#senderName').val('');
		$('#senderEmail').val('');
		$('#message').val('');

		$('#contactForm')
			.delay(messageDelay + 500)
			.fadeIn();
	} else {
		// Form submission failed: Display the failure message,
		// then redisplay the form
		$('#failureMessage').fadeIn().delay(messageDelay).fadeOut();
		$('#contactForm')
			.delay(messageDelay + 500)
			.fadeIn();
	}
}