// Project: Dynamic Date Selector (DtTvB) - 2006-03-16
// Script featured on JavaScript Kit- http://www.javascriptkit.com

// Get Element By Id
function ds_getel(id) {
        return document.getElementById(id);
}

// Get the left and the top of the element.
function ds_getleft(el) {
        var tmp = el.offsetLeft;
        el = el.offsetParent
        while(el) {
                tmp += el.offsetLeft;
                el = el.offsetParent;
        }
        return tmp;
}
function ds_gettop(el) {
        var tmp = el.offsetTop;
        el = el.offsetParent
        while(el) {
                tmp += el.offsetTop;
                el = el.offsetParent;
        }
        return tmp;
}
function ds_ob_clean() {
        ds_ob = '';
}
function ds_ob_flush() {
        ds_oe.innerHTML = ds_ob;
        ds_ob_clean();
}
function ds_echo(t) {
        ds_ob += t;
}

// Calendar template
function ds_template_main_above(t) {
        return '<table cellpadding="3" cellspacing="1" class="ds_tbl">'
             + '<tr>'
                 + '<td class="ds_head" style="cursor: pointer" onclick="ds_py();">&lt;&lt;</td>'
                 + '<td class="ds_head" style="cursor: pointer" onclick="ds_pm();">&lt;</td>'
                 + '<td class="ds_head" style="cursor: pointer" onclick="ds_hi();" colspan="3">Fermer</td>'
                 + '<td class="ds_head" style="cursor: pointer" onclick="ds_nm();">&gt;</td>'
                 + '<td class="ds_head" style="cursor: pointer" onclick="ds_ny();">&gt;&gt;</td>'
                 + '</tr>'
             + '<tr>'
                 + '<td colspan="7" class="ds_head">' + t + '</td>'
                 + '</tr>'
                 + '<tr>';
}

function ds_template_day_row(t) {
        return '<td class="ds_subhead">' + t + '</td>';
        // Define width in CSS, XHTML 1.0 Strict doesn't have width property for it.
}

function ds_template_new_week() {
        return '</tr><tr>';
}

function ds_template_blank_cell(colspan) {
        return '<td colspan="' + colspan + '"></td>'
}

function ds_template_day(d, m, y) {
        return '<td class="ds_cell" onclick="ds_onclick(' + d + ',' + m + ',' + y + ')">' + d + '</td>';
        // Define width the day row.
}

function ds_template_main_below() {
        return '</tr>'
             + '</table>';
}

// This one draws calendar...
function ds_draw_calendar(m, y) {
        // First clean the output buffer.
        ds_ob_clean();
        // Here we go, do the header
        ds_echo (ds_template_main_above(ds_monthnames[m - 1] + ' ' + y));
        for (i = 0; i < 7; i ++) {
                ds_echo (ds_template_day_row(ds_daynames[i]));
        }
        // Make a date object.
        var ds_dc_date = new Date();
        ds_dc_date.setMonth(m - 1);
        ds_dc_date.setFullYear(y);
        ds_dc_date.setDate(1);
        if (m == 1 || m == 3 || m == 5 || m == 7 || m == 8 || m == 10 || m == 12) {
                days = 31;
        } else if (m == 4 || m == 6 || m == 9 || m == 11) {
                days = 30;
        } else {
                days = (y % 4 == 0) ? 29 : 28;
        }
        var first_day = ds_dc_date.getDay();
        var first_loop = 1;
        // Start the first week
        ds_echo (ds_template_new_week());
        // If sunday is not the first day of the month, make a blank cell...
        if (first_day != 0) {
                ds_echo (ds_template_blank_cell(first_day));
        }
        var j = first_day;
        for (i = 0; i < days; i ++) {
                // Today is sunday, make a new week.
                // If this sunday is the first day of the month,
                // we've made a new row for you already.
                if (j == 0 && !first_loop) {
                        // New week!!
                        ds_echo (ds_template_new_week());
                }
                // Make a row of that day!
                ds_echo (ds_template_day(i + 1, m, y));
                // This is not first loop anymore...
                first_loop = 0;
                // What is the next day?
                j ++;
                j %= 7;
        }
        // Do the footer
        ds_echo (ds_template_main_below());
        // And let's display..
        ds_ob_flush();
        // Scroll it into view.
        ds_ce.scrollIntoView();
}

// A function to show the calendar.
// When user click on the date, it will set the content of t.
function ds_sh(t) {
        // Set the element to set...
        ds_element = t;
        // Make a new date, and set the current month and year.
        var ds_sh_date = new Date();
        ds_c_month = ds_sh_date.getMonth() + 1;
        ds_c_year = ds_sh_date.getFullYear();
        // Draw the calendar
        ds_draw_calendar(ds_c_month, ds_c_year);
        // To change the position properly, we must show it first.
        ds_ce.style.display = '';
        // Move the calendar container!
        the_left = ds_getleft(t);
        the_top = ds_gettop(t) + t.offsetHeight;
        ds_ce.style.left = the_left + 'px';
        ds_ce.style.top = the_top + 'px';
        // Scroll it into view.
        ds_ce.scrollIntoView();
}

// Hide the calendar.
function ds_hi() {
        ds_ce.style.display = 'none';
}

// Moves to the next month...
function ds_nm() {
        // Increase the current month.
        ds_c_month ++;
        // We have passed December, let's go to the next year.
        // Increase the current year, and set the current month to January.
        if (ds_c_month > 12) {
                ds_c_month = 1;
                ds_c_year++;
        }
        // Redraw the calendar.
        ds_draw_calendar(ds_c_month, ds_c_year);
}

// Moves to the previous month...
function ds_pm() {
        ds_c_month = ds_c_month - 1; // Can't use dash-dash here, it will make the page invalid.
        // We have passed January, let's go back to the previous year.
        // Decrease the current year, and set the current month to December.
        if (ds_c_month < 1) {
                ds_c_month = 12;
                ds_c_year = ds_c_year - 1; // Can't use dash-dash here, it will make the page invalid.
        }
        // Redraw the calendar.
        ds_draw_calendar(ds_c_month, ds_c_year);
}

// Moves to the next year...
function ds_ny() {
        // Increase the current year.
        ds_c_year++;
        // Redraw the calendar.
        ds_draw_calendar(ds_c_month, ds_c_year);
}

// Moves to the previous year...
function ds_py() {
        // Decrease the current year.
        ds_c_year = ds_c_year - 1; // Can't use dash-dash here, it will make the page invalid.
        // Redraw the calendar.
        ds_draw_calendar(ds_c_month, ds_c_year);
}

// Format the date to output.
function ds_format_date(d, m, y) {
        // 2 digits month.
        m2 = '00' + m;
        m2 = m2.substr(m2.length - 2);
        // 2 digits day.
        d2 = '00' + d;
        d2 = d2.substr(d2.length - 2);
        // YYYY-MM-DD
//      return y + '-' + m2 + '-' + d2;
        return d2 + '-' + m2 + '-' + y;
}

// When the user clicks the day.
function ds_onclick(d, m, y) {
        // Hide the calendar.
        ds_hi();
        // Set the value of it, if we can.
        if (typeof(ds_element.value) != 'undefined') {
                ds_element.value = ds_format_date(d, m, y);
        // Maybe we want to set the HTML in it.
        } else if (typeof(ds_element.innerHTML) != 'undefined') {
                ds_element.innerHTML = ds_format_date(d, m, y);
        // I don't know how should we display it, just alert it to user.
        } else {
                alert (ds_format_date(d, m, y));
        }
}

// Output Buffering
var ds_ob = '';

var ds_element; // Text Element...

var ds_monthnames = [
'Janvier', 'Février', 'Mars', 'Avril', 'Mai', 'Juin',
'Juillet', 'Aout', 'Septembre', 'Octobre', 'Novembre', 'Décembre'
]; // You can translate it for your language.

var ds_daynames = [
'Dim', 'Lun', 'Mar', 'Me', 'Jeu', 'Ven', 'Sam'
]; // You can translate it for your language.