function replaceHeaders()
{
	var styles =  {h1: 28, h2: 17};
	for (var tag in styles)
	{
		var headers = document.getElementsByTagName(tag);
		for (var i in headers)
		{
			if (!headers[i].innerHTML) continue;
			headers[i].innerHTML = '<img alt="" src="/headers/header.php?s=' + styles[tag] + '&t=' + headers[i].innerHTML + '" />';
		}
	}
}

window.onload = function()
{
	replaceHeaders();

	var contactForm = document.getElementById('contact');
	if (contactForm == undefined) return;

	var submitButton = document.getElementById('submit')
	submitButton.disabled = true;
	var enableSubmit = function()
	{
		this.changed = this.value.length > 0;
		if
		(
			subjectField.changed &&
			messageField.changed &&
			nameField.changed &&
			emailField.changed
		)
		{
			submitButton.disabled = false;
		}
	}

	var subjectField = document.getElementById('subject');
	var messageField = document.getElementById('message');
	var nameField = document.getElementById('name');
	var emailField = document.getElementById('email');

	subjectField.onkeydown = enableSubmit;
	messageField.onkeydown = enableSubmit;
	nameField.onkeydown = enableSubmit;
	emailField.onkeydown = enableSubmit;

	contactForm.onsubmit = function()
	{
		var message = "";
		if (subjectField.value.length == 0)
			message += "Betreff\n";
		if (messageField.value.length == 0)
			message += "Ihre Mitteilung\n";
		if (nameField.value.length == 0)
			message += "Name\n";
		if (emailField.value.length == 0)
			message += "E-Mail\n";

		if (message.length == 0)
			return true;

		alert("Bitte fuellen Sie alle Pflichtfelder aus:\n" + message);
		return false;
	}
}