function drawCalendar(lang)
{
    calendar = document.getElementById('calendarBackground');
    date = new Date();

    yesterday = new Date(date.getTime() - 86400000);
    drawDay(calendar, yesterday, ['c1', 'c2', 'c3'], lang);

    drawDay(calendar, date, ['c4', 'c5', 'c6'], lang);

    tomorrow = new Date(date.getTime() + 86400000);
    drawDay(calendar, tomorrow, ['c7'], lang);
}

function drawDay(calendar, date, ids, lang)
{
    dayOfWeek = date.getDay();
    dayOfMonth = date.getDate();
    firstNumber = Math.floor(dayOfMonth / 10);
    secondNumber = dayOfMonth % 10;

    if (firstNumber && ids[0]) {
        appendCalendarNumber(calendar, ids[0], firstNumber.toString());
    }

    if (ids[1]) {
        appendCalendarNumber(calendar, ids[1], secondNumber.toString());
    }

    if (ids[1]) {
        appendCalendarNumber(calendar, ids[2], 'd' + dayOfWeek.toString(), lang);
    }
}

function appendCalendarNumber(parent, id, number, lang)
{
    imageElement = document.createElement('img');
    imageElement.setAttribute('id', id);
    if (lang) {
	    imageElement.src = './img/calendar_' + number + '_' + lang + '.png';
	} else {
	    imageElement.src = './img/calendar_' + number + '.png';
    }
    parent.appendChild(imageElement);
}