//
// JavaScript Event Calendar
//
// Version: 1.0
// Date: November 15, 1998
// For information: http://members.aol.com/kevinilsen  or kilsen@m-vation.com
//

// Configurable values are set to defaults here; can override them before calling Calendar( ) from the HTML page

var SpecialDay=8;// 1=Sunday, 2=Monday, . . . 7=Saturday
var FontSize=1;
var ColorBackground="ffffcc";
var ColorSpecialDay = "black";
var ColorToday = "blue";
var ColorEvent = "red";

// Initialize the range of the calendar to Jan - Dec of the current year.  Calls to DefineEvent( ) will change this
// as needed; it is also possible to explicitly override the range before calling Calendar( ) from the HTML page.

var today = new Date();
var FirstMonth=GetFullYear(today) * 100 + 1;
var LastMonth=FirstMonth + 11;

// Events[] is a SPARSE array; Call DefineEvent( ) to populate it
var Events = new Array;

// Each event is defined by calling the DefineEvent( ) routine with the following parameters:
//
//   DefineEvent(EventDate, EventDescription, EventLink, Image, Width, Height)
//        EventDate is a numeric value in the format YYYYMMDD
//        EvenDescription is a string that can include embedded HTML tags (e.g., <BR>, <strong>, etc.)
//        EventLink is the URL of the target page if a hyperlink is desired from this event entry
//        Image is the URL of the image if you want to display an image with this event
//        Width is the width of the image in pixels
//        Height is the height of the image in pixels

function DefineEvent(EventDate, EventDescription, EventLink, Image, Width, Height) {
var tmp;

// Build the HTML string for this event: image (optional), link (optional), and description
tmp = "";
if (Image != "")
tmp = tmp + '<img src="' + Image + '"  width="' + Width + '" height="' + Height + '" align="left" valign="top">';
if (EventLink != "")
tmp = tmp + '<a href="' + EventLink + '">';
tmp = tmp + EventDescription;
if (EventLink != "") tmp = tmp + '</a>';

// If an event already exists for this date, append the new event to it.
if (Events[EventDate])
Events[EventDate] += "<BR>" + tmp;
else
Events[EventDate] = tmp;

// Adjust the minimum and maximum month & year to include this date
tmp = Math.floor(EventDate / 100);
if (tmp < FirstMonth) FirstMonth = tmp;
if (tmp > LastMonth) LastMonth = tmp;
}

// Utility function to populate an array with values
function arr() {
for (var n=0;n<arr.arguments.length;n++) {
this[n+1] = arr.arguments[n];
}
}

// Create the array of month names (used in various places)
var months = new arr("January","February","March","April","May","June","July","August","September","October","November","December");

// Calendar( ) is the only routine that needs to be called to display the calendar (modified to start Saturday Instead of Sunday also altered other array to +2 see further below)

function Calendar( ) {
var curdy, curmo, yr, mo, dy, dayofweek, yearmonth, bgn, lastday, jump;
var weekdays = new arr("Sat","Sun","Mon","Tue","Wed","Thu","Fri");
var thispage = window.location.pathname;

// Save current day and month for comparison
curdy = today.getDate();
curmo = today.getMonth()+1;

// Default to current month and year
mo = curmo;
yr = GetFullYear(today);
yearmonth = (yr * 100) + mo;

// If querystring parameter is present, get the month/year ("calendar.htm?YYYYMM")
if (location.search.length > 1) {
yearmonth = parseInt(location.search.substring(1,location.search.length));
if ((""+yearmonth).length == 6) {
mo = yearmonth % 100;
yr = (yearmonth - mo) / 100;
}
}

// Constrain to the range of months with events
if (yearmonth < FirstMonth) {
mo = FirstMonth % 100;
yr = (FirstMonth - mo) / 100;
yearmonth = FirstMonth;
}
if (yearmonth > LastMonth) {
mo = LastMonth % 100;
yr = (LastMonth - mo) / 100;
yearmonth = LastMonth;
}

// Create a date object for the first day of the desired month (I modified the value from + 1 to +2 as I changed start day to Saturday - see array further up)
bgn = new Date(months[mo] + " 2," + yr);
// Get the day-of-week of the first day, and the # days in the month
dayofweek = bgn.getDay();
lastday = NumDaysIn(mo,yr);
document.write("<TABLE BORDER=2 BGCOLOR="+ColorBackground+"><TR><TD ALIGN=CENTER COLSPAN=7><FONT SIZE="+FontSize+"><B>"+months[mo]+" "+yr+"</B></FONT></TD></TR><TR>");
for (var i=1;i<=7;i++){
document.write("<TD ALIGN=CENTER WIDTH=14%><FONT SIZE=1>"+weekdays[i]+"</FONT></TD>");
}
document.write("</TR><TR>");
dy = 1;
// Special handling for the first week of the month
for (var i=1;i<=7;i++) {
// If the day is less than the day of the
// week determined to be the first day
// of the month, print a space in
// this cell of the table.
if (i <= dayofweek){
document.write("<TD ALIGN=CENTER><FONT SIZE="+FontSize+">&nbsp;</FONT></TD>");
}
// Otherwise, write date and the event,
// if any, in this cell of the table.
else {
ShowDate(yr,mo,dy,i,curmo,curdy);
dy++;
}
}
document.write("</TR><TR>");
// Rest of the weeks . . .
while (dy <= lastday) {
for (var i=1;i<=7;i++) {
// If the day is greater than the last
// day of the month, print a space in
// this cell of the table.
if (dy > lastday) {
document.write("<TD ALIGN=CENTER>&nbsp;</TD>");
}
// Otherwise, write date and the event,
// if any, in this cell of the table.
else {
ShowDate(yr,mo,dy,i,curmo,curdy);
dy++;
}
}
document.write("</TR><TR>");
}

jump = "";
if (yearmonth > FirstMonth)
jump += '<a href="' + thispage + '?'+PrevYearMonth(yearmonth)+'">&lt;-- View '+months[PrevMonth(mo)]+'</a>';
if ((yearmonth > FirstMonth) && (yearmonth < LastMonth))
jump += " &nbsp; | &nbsp; ";
if (yearmonth < LastMonth)
jump += '<a href="' + thispage + '?'+NextYearMonth(yearmonth)+'">View '+months[NextMonth(mo)]+' --&gt;</a>';
document.write("</TR><TR><TD colspan=7 align=center>"+jump+"</TD></TR>");

document.write("</FORM></TD></TR></TABLE>");
}

// Display a date in the appropriate color, with events (if there are any)

function ShowDate(yr, mo, dy, dayofweek, currentmonth, currentday) {
var ind, HighlightEvent, tmp;

document.write("<TD ALIGN=CENTER VALIGN=TOP><P ALIGN=RIGHT><FONT SIZE="+FontSize);
HighlightEvent = true;
if (dayofweek == SpecialDay) {
document.write(" COLOR=" + ColorSpecialDay);
HighlightEvent = false;
}
if ((mo == currentmonth) && (dy == currentday)) {
document.write(" COLOR=" + ColorToday);
HighlightEvent = false;
}
ind = (((yr * 100) + mo) * 100) + dy;
if (Events[ind]) {
tmp = Events[ind];
if (HighlightEvent) {
 document.write(" COLOR=" + ColorEvent);
}
} else tmp="&nbsp;<BR>&nbsp;";
document.write("><B>"+dy+"</B></ALIGN></FONT></P><FONT SIZE=1>"+tmp+"</TD>");
}


// Remaining routines are utilities used above

function NumDaysIn(mo,yr) {
if (mo==4 || mo==6 || mo==9 || mo==11) return 30;
else if ((mo==2) && LeapYear(yr)) return 29;
else if (mo==2) return 28;
else return 31;
}

function LeapYear(yr) {
if (((yr % 4 == 0) && yr % 100 != 0) || yr % 400 == 0) return true;
else return false;
}

// fixes a Netscape 2 and 3 bug
function GetFullYear(d) { // d is a date object
var yr;

yr = d.getYear();
if (yr < 1000)
yr +=1900;
return yr;
}

function PrevMonth(mth) {
if (mth == 1) return 12;
else return (mth-1);
}

function NextMonth(mth) {
if (mth == 12) return 1;
else return (mth+1);
}

function PrevYearMonth(yrmth) {
if ((yrmth % 100) == 1) return ((yrmth-100)+11);
else return (yrmth-1);
}

function NextYearMonth(yrmth) {
if ((yrmth % 100) == 12) return ((yrmth-11)+100);
else return (yrmth+1);
}

function JumpTo(calendar, thispage) {
var sel, yrmo;

sel = calendar.selectedIndex;
yrmo = calendar.form.jumpmonth[sel].value;
document.location = thispage + "?" + yrmo;
}

function BuildSelectionList(current,thispage) {
var mo, yr, yearmonth;

yearmonth = FirstMonth;
document.write("<select name=\"jumpmonth\" size=1 onchange=\"JumpTo(this,'" + thispage + "')\">");
while (yearmonth <= LastMonth) {
mo = yearmonth % 100;
yr = (yearmonth - mo) / 100;
document.write("<option value=");
document.write(yearmonth);
if (yearmonth == current) document.write(" selected");
document.write(">");
document.write(months[mo]+" "+yr);
yearmonth = NextYearMonth(yearmonth);
}
document.write("</select>");
}