alertbox = function() {}
alertbox.warning = function (dest, heading, message) {
  $('#' + dest + ' .alertbox').html('<div class="alert"><a class="close" data-dismiss="alert" href="#">&times;</a><h4 class="alert-heading">' + heading + '</h4>' + message + '</div>');
}
alertbox.error = function (dest, heading, message) {
  $('#' + dest + ' .alertbox').html('<div class="alert alert-error"><a class="close" data-dismiss="alert" href="#">&times;</a><h4 class="alert-heading">' + heading + '</h4>' + message + '</div>');
}
alertbox.info = function (dest, heading, message) {
  $('#' + dest + ' .alertbox').html('<div class="alert alert-info"><a class="close" data-dismiss="alert" href="#">&times;</a><h4 class="alert-heading">' + heading + '</h4>' + message + '</div>');
}

var weekday = new Array(7);
weekday[0] =  "Sonntag";
weekday[1] = "Montag";
weekday[2] = "Dienstag";
weekday[3] = "Mittwoch";
weekday[4] = "Donnerstag";
weekday[5] = "Freitag";
weekday[6] = "Samstag";

function format_datetime(d) {
  if(Object.prototype.toString.call(d) === "[object Date]") {
    var daynames = new Array('So', 'Mo', 'Di', 'Mi', 'Do', 'Fr', 'Sa');
    var datetimestr = daynames[d.getDay()];
    datetimestr += ' ' + d.getDate();
    datetimestr += '.' + (d.getMonth() + 1);
    datetimestr += '.' + d.getFullYear();
    datetimestr += (d.getHours() > 9 ? ' ' : ' 0') + d.getHours();
    datetimestr += (d.getMinutes() > 9 ? ':' : ':0') + d.getMinutes();
    datetimestr += (d.getSeconds() > 9 ? ':' : ':0') + d.getSeconds();
    return datetimestr;
  }
  return d;
}

function get_rd_week() {
  //
  // This computes the current Rivendell Week based on the number
  // of weeks since epoch.
  //
  // Explanation:
  //  epoch was at 01.01.1970 which was a Thursday.
  //  Monday in that week is (s-from-epoch + 3*24*60*60) seconds ago.
  //  Divide this by (7*24*60*60) and you get the number of
  //  weeks since the Monday in the week of epoch.
  //  This week had week number 3 so add an offset of 2 and
  //  get the modulo of 4. This rounded down gives you the current week
  //  with 0 meaning Week 1. So add 1 to that number and you will get
  //  the current RD week.
  //
  var sEpoch = (+new Date()) / 1000;
  var week = Math.floor((((sEpoch + 259200)/604800) + 2) % 4) + 1
  return week;
}