var url_calendar = '/js/pma_calendar/pma_calendar.php';

var day;
var month;
var year;
var dateField;

var month_names = new Array("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec");
var day_names = new Array("Sun","Mon","Tue","Wed","Thu","Fri","Sat");

/**
 * Opens calendar window.
 *
 * @param   string      calendar.php parameters
 * @param   string      form name
 * @param   string      field name
 * @param   string      edit type - date/timestamp
 */
function openCalendar(form, field) {
    window.open(url_calendar, "mycalendar", "width=400,height=200,status=yes");
    dateField = eval("document." + form + "." + field);
}

/**
 * Formats number to two digits.
 *
 * @param   int number to format.
 */
function formatNum2(i, valtype) {
    f = (i < 10 ? '0' : '') + i;
    if (valtype && valtype != '') {
        switch(valtype) {
            case 'month':
                f = (f > 12 ? 12 : f);
                break;
            case 'day':
                f = (f > 31 ? 31 : f);
                break;
            default:
                f = (f > 59 ? 59 : f);
                break;
        }
    }

    return f;
}

/**
 * Formats number to four digits.
 *
 * @param   int number to format.
 */
function formatNum4(i) {
    return (i < 1000 ? i < 100 ? i < 10 ? '000' : '00' : '0' : '') + i;
}

/**
 * Initializes calendar window.
 */
function initCalendar() {
    if (!year && !month && !day) {
        /* Called for first time */
        if (window.opener.dateField.value) {
            value = window.opener.dateField.value;
			date        = value.split("-");
			day         = parseInt(date[2],10);
			month       = parseInt(date[1],10) - 1;
			year        = parseInt(date[0],10);
		}

        if (isNaN(year) || isNaN(month) || isNaN(day) || day == 0) {
            dt      = new Date();
            year    = dt.getFullYear();
            month   = dt.getMonth();
            day     = dt.getDate();
        }
    } else {
        /* Moving in calendar */
        if (month > 11) {
            month = 0;
            year++;
        }
        if (month < 0) {
            month = 11;
            year--;
        }
    }

	// grab the div which which contain our calendar
    if (document.getElementById) {
        cnt = document.getElementById("calendar_data");
    } else if (document.all) {
        cnt = document.all["calendar_data"];
    }

	// clear the old html. why?
    // cnt.innerHTML = "";

    str = '';
    str += '<table class="calendar">';
    str += '<tr>';
    str += '<th width="50%">';
    str += '<form method="NONE" onsubmit="return 0">';
    str += '<a href="javascript:month--; initCalendar();">&laquo;</a> ';
    str += '<select id="select_month" name="monthsel" onchange="month = parseInt(document.getElementById(\'select_month\').value); initCalendar();">';
    for (i =0; i < 12; i++) {
        selected = ((i == month) ? ' selected="selected"' : '');
        str += '<option value="' + i + '" ' + selected + '>' + month_names[i] + '</option>';
    }
    str += '</select>';
    str += ' <a href="javascript:month++; initCalendar();">&raquo;</a>';
    str += '</form>';
    str += '</th>';
    str += '<th width="50%">';
    str += '<form method="NONE" onsubmit="return 0">';
    str += '<a href="javascript:year--; initCalendar();">&laquo;</a> ';
    str += '<select id="select_year" name="yearsel" onchange="year = parseInt(document.getElementById(\'select_year\').value); initCalendar();">';
    for (i = year - 25; i < year + 25; i++) {
        if (i == year) selected = ' selected="selected"';
        else selected = '';
        str += '<option value="' + i + '" ' + selected + '>' + i + '</option>';
    }
    str += '</select>';
    str += ' <a href="javascript:year++; initCalendar();">&raquo;</a>';
    str += '</form>';
    str += '</th>';
    str += '</tr>';
    str += '</table>';

    str += '<table class="calendar"><tr>';
    for (i = 0; i < 7; i++) {
        str += "<th>" + day_names[i] + "</th>";
    }
    str += "</tr>";


    str += "<tr>";

    var firstDay = new Date(year, month, 1).getDay();
    var lastDay = new Date(year, month + 1, 0).getDate();


    dayInWeek = 0;


    // ending days of last month which need to be visible
    for (i = 0; i < firstDay; i++) {
        str += "<td>&nbsp;</td>";
        dayInWeek++;
    }

    // the days of this month
    for (i = 1; i <= lastDay; i++) {
        if (dayInWeek == 7) {
            str += "</tr><tr>";
            dayInWeek = 0;
        }

        dispmonth = 1 + month;

        actVal = formatNum4(year) + "-" + formatNum2(dispmonth, 'month') + "-" + formatNum2(i, 'day');
        style = (i == day) ? ' class="selected"' : '';
        str += "<td" + style + "><a href=\"javascript:returnDate('" + actVal + "');\">" + i + "</a></td>"
        dayInWeek++;
    }

    // starting days of next month which need to be visible
    for (i = dayInWeek; i < 7; i++) {
        str += "<td>&nbsp;</td>";
    }

    str += "</tr></table>";

    cnt.innerHTML = str;

}

/**
 * Returns date from calendar.
 *
 * @param   string     date text
 */
function returnDate(d) {
    window.opener.dateField.value = d;
    window.close();
}