/* makes links with attribute rel="external" open in a new window */
function externalLinks() { 
	if (!document.getElementsByTagName) return; 
	var anchors = document.getElementsByTagName("a"); 
	for (var i = 0; i < anchors.length; i++) { 
		var anchor = anchors[i]; 
		if (anchor.getAttribute("href") && anchor.getAttribute("rel") == "external") {
			anchor.target = "_blank"; 
		}
	}
}

if (window.addEventListener) {
	window.addEventListener('load', externalLinks, false); 
} else if (window.attachEvent) { 
	window.attachEvent('onload', externalLinks);
}

String.prototype.trim = function () {
    return this.replace(/^\s*/,'')
                     .replace(/\s*$/,'');
};

String.prototype.isEmailAddress = function() {
	var emailTestRegex = /^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
	return this.match(emailTestRegex);
}
function validateForm(form) {
	var emailTestRegex = /^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
	// TODO alleen verplicht stellen wat *essentieel* verplicht is
	
	if (form.naam.value.trim() == '') {
		alert('Please fill in a name.');
		return false;
	} else if (form.email.value.trim() == '') {
		alert('Please fill in an e-mail address.');
		return false;
	} else if (!(form.email.value.match(emailTestRegex))) {
		alert('Please fill in a correct e-mail address');
		return false;
	}
	return true;
}