var ERROR_1 = "You need to enter some tags, a user id, or a photo set id.";
var ERROR_2 = "Please select a presentation style.";

function preview(input_id, name) {
	var user_id = escape(trim(document.getElementById("user_id").value));
	var tags = escape(trim(document.getElementById("tags").value));
	var photoset_id = escape(trim(document.getElementById("photoset_id").value));
	var per_page = document.getElementById("per_page").value;
	if (tags == "" && user_id == "" && photoset_id == "") {
		alert(ERROR_1);
		document.getElementById("tags").focus();
	}
	else {
		document.getElementById(input_id).checked = true;
		var u = "viewer.php?template_id=" + name + "&user_id=" + user_id + "&tags=" + tags + "&photoset_id=" + photoset_id + "&per_page=" + per_page;
		var p = window.open(u, "", "width=1000,height=700,scrollbars,resizable");
		p.focus();
	}
}

function trim(s) {
	while (s.charAt(0) == " ") {
		s = s.substring(1);
	}
	while (s.charAt(s.length-1) == " ") {
		s = s.substring(0, s.length-1);
	}
	while (s.indexOf("  ") > -1) {
		s = s.replace("  ", " ");
	}
	return s;
}

function validate() {
	var user_id = escape(trim(document.getElementById("user_id").value));
	var tags = escape(trim(document.getElementById("tags").value));
	var photoset_id = escape(trim(document.getElementById("photoset_id").value));
	if (tags == "" && user_id == "" && photoset_id == "") {
		alert(ERROR_1);
		document.getElementById("tags").focus();
		return false;
	}
	var f = document.forms["show"];
	for (var i = 0; i < f.elements.length; i++) {
		if (f.elements[i].type == "radio" && f.elements[i].checked) {
			return true;
		}
	}
	alert(ERROR_2);
	return false;
}