Userscript that adds Google Calendar links to the De Oosterpoort website

deoosterpoort-to-gcal.user.js

// ==UserScript==
// @name          GCal links for De Oosterpoort
// @namespace     http://ikhoefgeen.nl/userscripts
// @description	  Create Google Calendar events directly from De Oosterpoort website
// @include       http://www.de-oosterpoort.nl/programma/*
// ==/UserScript==

var DeOosterpoort = {}

DeOosterpoort.findData = function(root)
{
	var header = root.querySelector('#voorstelling h1'),
		specs = root.querySelectorAll("#voorstelling .detail-info li > span"),
		event = new iCal.Event;

	if (!header || specs.size == 0)
		return null;

	event.name = header.firstChild.data.trim();

	for (var i = 0; i < specs.length; ++i)
	{
		if (!specs[i].firstChild || !specs[i].nextSibling)
			continue;
		
		var label = specs[i].firstChild.data.trim(),
			value = specs[i].nextSibling.data.trim();
		
		if (label == "Datum") {
			if (!DeOosterpoort.parseDatum(value, event))
				return null;
		}
		else if (label == "Tijdstip") {
			if (!DeOosterpoort.parseTijdstip(value, event))
				return null;
		}
		else if (label == "Locatie") {
			event.location = value;
		}
	}

	return event;
};

DeOosterpoort.parseDatum = function(datum, event)
{
	var parts = datum.match(/^\w+\ (\d+) (\w+) (\d+)$/);

	if (!parts)
		return false;

	var month = [
		'januari', 'februari', 'maart',
		'april', 'mei', 'juni',
		'juli', 'augustus', 'september',
		'oktober', 'november', 'december'
	].indexOf(parts[2]);

	['from', 'till'].forEach(function(range) {
		event[range].setYear(parts[3]);
		event[range].setMonth(month);
		event[range].setDate(parts[1]);
	});

	return true;
};

DeOosterpoort.parseTijdstip = function(tijdstip, event)
{
	var parts = tijdstip.match(/^(\d{1,2}):(\d\d)(?:\s+tot (\d{1,2}):(\d\d))?$/);
	
	if (!parts)
		return false;
	
	event.from.setHours(parts[1]);
	event.from.setMinutes(parts[2]);

	if (typeof parts[3] !== 'undefined' && typeof parts[4] !== 'undefined')
	{
		event.till.setHours(parts[3]);
		event.till.setMinutes(parts[4]);
	}
	else
	{
		event.till.setHours(parseInt(parts[1]) + 1);
		event.till.setMinutes(parts[2]);
	}

	return true;
}

function align(length, filler, value)
{
	value = "" + value; // now it is a string for sure! :P
	return repeat(filler, length - value.length) + value;
}

function repeat(character, times)
{
	var output = '';

	while (times-- > 0)
		output += character;
	
	return output;
}


var iCal = {};

iCal.Event = function() {
	this.from = new Date;
	this.till = new Date;
	this.name = '[name]';
	this.location = '[location]';
	this.link = document.location.href;
}

iCal.Event.prototype.toGoogleCalendarLink = function()
{
	var ical_format = 'Ymd\THis\Z';

	return [
		'http://www.google.com/calendar/event?action=TEMPLATE',
		'text=' + encodeURIComponent(this.name),
		'dates=' + iCal.formatDate(ical_format, this.from) + '/' + iCal.formatDate(ical_format, this.till),
		'location=' + encodeURIComponent(this.location),
		'trp=true',
		'sprop=' + encodeURIComponent(this.link)
	].join("&");
}

iCal.formatDate = function(format, date)
{
	var output = '';

	for (var i = 0; i < format.length; ++i)
	{
		switch (format[i])
		{
			case '\\':
				output += format[++i];
				break;
			
			case 'Y':
				output += date.getUTCFullYear();
				break;
			
			case 'm':
				output += align(2, '0', date.getUTCMonth() + 1);
				break;
			
			case 'd':
				output += align(2, '0', date.getUTCDate());
				break;
			
			case 'H':
				output += align(2, '0', date.getUTCHours());
				break;
			
			case 'i':
				output += align(2, '0', date.getUTCMinutes());
				break;
			
			case 's':
				output += align(2, '0', date.getUTCSeconds());
				break;
			
			default:
				output += format[i];
				break;
		}
	}

	return output;
}

function main()
{
	var event = DeOosterpoort.findData(document);

	if (!event)
		return;
	
	var link = document.createElement('a');
	link.href = event.toGoogleCalendarLink();
	link.target = '_blank';
	link.appendChild(document.createTextNode('GCal'));

	document.querySelector('#voorstelling .detail-info li').appendChild(link);
}

main();