// JavaScript Document
//
// Written by Marc Lieberman

var now = new Date;
var curmonth = now.getMonth();
var curyear = now.getFullYear();
// initialize month and year
var month = curmonth;
var year = curyear;
var monName = new Array ("jan", "feb", "mar", "apr", "may", "jun", "july", "aug", "sept", "oct", "nov", "dec");

function loadCalendar(when)
{
if (when=="now")  {
  textyear = year + "";
  shortyear = textyear.substr(2,2);
  frames[0].location = "/counselor/calendar/" + monName[month] + shortyear + ".jsp";
 }
else if (when=="next") {
  month = month + 1;
  if (month == 12) {
    month = 0;
	year = year + 1;
  }
  textyear = year + "";
  shortyear = textyear.substr(2,2);
  frames[0].location = "/counselor/calendar/" + monName[month] + shortyear + ".jsp"; 
 }
else if (when=="prev") {
  month = month - 1;
  if (month < 0) {
    month = 11;
	year = year - 1;
  }
  textyear = year + "";
  shortyear = textyear.substr(2,2);
  frames[0].location = "/counselor/calendar/" + monName[month] + shortyear + ".jsp";
 }
	
setVisibility()

}

function setVisibility() {
  // Only show "previous" button if user has moved forward from the current month/year
  if (month > curmonth || year > curyear) {
    document.getElementById('previous').style.visibility = 'visible';
  } else {
    document.getElementById('previous').style.visibility = 'hidden';
  }
  // Only show "next" button for max 5 months in the future
  maxmonth = curmonth + 5;
  maxyear = curyear;
  if (maxmonth >= 12) {
    maxmonth = maxmonth-12;
	maxyear = curyear + 1;
  }
  if (month>=maxmonth && year>=maxyear) {
      document.getElementById('next').style.visibility = 'hidden';
  } else {
    document.getElementById('next').style.visibility = 'visible';
  }
}