//
// Enhanced JavaScript Event Calendar
//
// Author:  Rick Pike
// Website: http://calendar.pikesys.com
// Email: calendar@pikesys.com
//'Version 0.3 - (07-May-2004)
//
// based on an earlier script by Kevin Ilsen (http://calendar.ilsen.net or kevin@ilsen.net)

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

var SpecialDay=1; // 1=Sunday, 2=Monday, . . . 7=Saturday
var ColorBackground="ffffcc";
var ColorSpecialDay = "red";
var ColorToday = "green";
var ColorEvent = "blue";
var showAltDate = false;   // add display of alternate date using results from user supplied "getAltMonth(dy, mo, yr, last)" and "getAltDate(dy, mo, yr)" functions
var showHolidays = false;  // add display of holidays using result from user supplied "holidays(dy, mo, yr)" function
var showAltHoly = false;   // add display of alternate holidays using result from user supplied "getAltHoly(dy, mo, yr)" function
var showMsgBox = true;  // span empty cells (before 1st day and after last) for messageBox use
var showMini = true;       // add minimonth display of prior and next months if first and/or last boxes are available 
var showNav = true;     // enable month navigation (might disable for print version)
var showImages = true;  // enable event images (might disable for print version)
var showLinks = true;      // enable event hyperlinks (might disable for print version)
var msgBoxColor = "#ffcc99";
var navColor = "#ffff99";
var imageAlign = "left";   // default event image alignment
var imageScale = 100;      // percent scale factor for images
var altAlign = true;       // alternate left/right alignment of event images on same date for readability
var DefaultFormat = "custom"; // for compatibility; set to "layer" to simplify formatting
var ExportPage = "";       // name of html page for displaying event text for export
var PrintPage = "";     // name of html page for printer-friendly format

// all format codes must have "|" to separate before and after tags
var DateFontSize=5;
var AltDateFormat = "<font color=#999999 size=2>|</font>";
var MonthFormat = "<font size=" + DateFontSize + "><b>|</b></font>";
var AltMonthFormat = "<br><font color=#999999 size=" + DateFontSize/2 + ">|</font>";
var HolidayFormat = "<font color=#999999 size=2><b><center>|</center></b></font>";
var AltHolyFormat = "<font  size=2><b><center>|</center></b></font>";
var DefaultLayerFormat = "<font size=2>|</font>";

var defaultMsgBox = "Note: The information here may not be current; please confirm dates and times.<p>";

// Initialize the range of the calendar to Jan - Dec of the current year.
// Event definitions will change this as needed; or it can be explicitly
// overridden before calling Calendar( ) from the HTML page.

var today = new Date();

var FirstMonth=GetFullYear(today) * 100 + today.getMonth()+1;;
var LastMonth=(GetFullYear(today) + 2) * 100 + today.getMonth()+1;;
//var LastMonth=FirstMonth + 11;

// Layers[] is an array of layer names and default formats. Call DefineLayer( ) to add the
// layer name and corresponding format. New layer names in event definitions will
// be added automatically (watch case and spelling).

var Layers = new Array;
var LayerString = "|";
var layerCount = 0;
var layerChange = false;

// MsgBoxes[] is a SPARSE array; Call AddMsgBox( ) to populate it

var MsgBoxes = new Array;

// Events[] is a SPARSE array; Call AddEvent( ) to populate it or DefineEvent( ) for
// compatibility with existing calendar definition scripts.

var Events = new Array;

// Each event is defined by calling the AddEvent( ) routine with the following parameters:
//
//   AddEvent(Date, Description, Layer, Format, Link, Image, Width, Height, Align, Alt)
//        Date is a numeric value in the format YYYYMMDD
//        Description is a string (may include embedded HTML tags such as <BR>, <strong>, etc.)
//        Layer is an event category whose display on the calendar can be toggled on/off by the user
//        Format specifies the source of the format info for Description. Note that any embedded
//        formats in Description will still be applied; this argument is primarily to provide
//        a more convenient way to specify formats. 
//            "layer" = use default format from layer definition (plus any embedded tags!)
//            "custom" = only use format tags embedded in Description string
//            "<...>|</...>" = series of before and after tags separated by a "|" to wrap around
//               Description (plus any embedded tags!)  
//        Link 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
//        Align is the alignment of the image such as "left", or "right"
//        Alt is the alternate text of the image (for mouseover or non-graphic browser)

// The function DefineEvent(Date, Description, Link, Image, Width, Height) is used
// for compatibility with previous calendar definition scripts

// Event constructor
function Event(description, instructor, trs, time, layer, format, link, image, width, height, align, alt) {

   this.description = description;
   this.instructor  = instructor;
   this.trs  = trs;
   this.time = time;
   if (link) this.link = link;
   if (image) {
      this.image = image;
      if (width) this.width = width;
      if (height) this.height = height;
      if (align) this.align = align;
      if (alt) this.alt = alt;
      //alert("Event: ("+this.width+","+this.height+")");
   }
   this.layer = (layer ? layer : "default");    // must have some associated layer
   
   if (format) {
      if (CheckFormat(format)) this.format = format;
   }
}


function AddEvent(Date, Description, TRS, Desc2, Time, Fee, Instructor, Rating, Layer, HTMLFormat, Link, Image, Width, Height, Align, Alt) {
   var i;
   if(Layer == FixedLayer) 
   {
      if (!Events[Date]) Events[Date] = new Array;
      i = Events[Date].length;
     // Description = Description + "<br />" + Time;
      Events[Date][i] = new Event(Description, Instructor, TRS, Time, Layer, HTMLFormat, Link, Image, Width, Height, Align, Alt);

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

      // if EventLayer not in Layers, add it
      // NOTE: watch case in DefineLayer and DefineEvent to avoid undesired "duplicates"

      //alert("AddEvent("+Date+","+Description+","+Width+","+Height+"...)");
      if (Layer && !Layers[Layer]) DefineLayer(Layer);
    }
}

// Layer constructor
function Layer(format, show) {
   if (format) {  
      if (format.indexOf("|")>0) {
         this.format = format;
      } else {
         alert("Invalid Calendar Format String: " + format);
      }
   } else {
      this.format = DefaultLayerFormat;
   }
   this.show = (show=="false" ? "false" : "true"); // watch boolean vs. string arg
}

function DefineLayer(LayerName, LayerFormat, LayerShow) {
   Layers[LayerName] = new Layer(LayerFormat, LayerShow);
   layerCount++;
}

// 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
var cookieName = "layerCalendar";
var pre, post, tmp, gloMo, gloYr, gloYearmonth;

function Calendar( ) {
   var curdy, curmo, yr, mo, dy, firstday, yearmonth, bgn, lastdate, jump;
   var weekdays = new arr("Sun","Mon","Tue","Wed","Thu","Fri","Sat");
   var thispage = window.location.pathname;
   var myMsgBox = "Put this FREE calendar script on your own site; see <a href=http://calendar.pikesys.com>calendar.pikesys.com</a>.<p>";

   // define default MsgBox messages
   AddMsgBox(0, defaultMsgBox);
   AddMsgBox(0, myMsgBox);
   
   // Save current day and month for comparison
   curdy = today.getDate();
   curmo = today.getMonth()+1;
   
   initCal(curmo);
   mo = gloMo; yr = gloYr; yearmonth = gloYearmonth;
 //  getLayersVisible();     // get layer visibility settings from cookie
   
   // Create a date object for the first day of the desired month
   bgn = new Date(months[mo] + " 1," + yr);
   // Get the day-of-week of the first day, and the # days in the month
   firstday = bgn.getDay();
   lastdate = NumDaysIn(mo,yr);
   lastday = 1+(firstday + lastdate - 1)%7;
   prev = next = "&nbsp;";
   if (showNav) {
      if (yearmonth > FirstMonth)
         prev = '<a class="navlink" href="' + thispage + '?'+PrevYearMonth(yearmonth)+'">&lt;-- View '+months[PrevMonth(mo)]+'</a>';
      if (yearmonth < LastMonth)
         next += '<a class="navlink" href="' + thispage + '?'+NextYearMonth(yearmonth)+'">View '+months[NextMonth(mo)]+' --&gt;</a>';
   }

   parseFormat(MonthFormat);
   tmp = "<TABLE BORDER=2 BGCOLOR="+ColorBackground+"><TR BORDER=0 BGCOLOR="+navColor+">";
   tmp += "<TD ALIGN=CENTER BGCOLOR="+navColor+">" + prev + "</TD>";
   tmp += "<TD ALIGN=CENTER COLSPAN=5>" + pre + months[mo] + " " + yr + post;
   
   if (showAltDate) {
      parseFormat(AltMonthFormat);
      altMonth = getAltMonth(1, mo, yr, lastdate);
      tmp += pre + (altMonth ? altMonth : "") + post;
   }
   tmp += "</TD><TD ALIGN=CENTER BGCOLOR="+navColor+">" + next + "</TD></TR>";
   document.write(tmp);
   document.write("<TR BGCOLOR="+navColor+">");
   
   for (var i=1;i<=7;i++){
      document.write("<TD ALIGN=CENTER WIDTH=14%><FONT SIZE=2>"+weekdays[i]+"</FONT></TD>");
   }
   dy = 1;
   document.write("</TR><TR>");

   while (dy <= lastdate) {
      for (var i=1; i<=7; i++) {
         
         // If the day cell is before the first day of the month, print a miniMonth display of previous month in the first cell, 
         // otherwise print a space in this cell of the table.
         if (dy == 1 && i <= firstday) {
            if (i == 1) {
               if (showMini) {
                  document.write("<TD BGCOLOR="+ColorBackground+">");   
                  MiniMonth(PrevYearMonth(yearmonth));
               } else {
                  document.write("<TD>&nbsp;");
               }
            } else if (showMsgBox && i==2) {    // span empty cells to allow messageBox
               msgSpan = firstday - 1;
               document.write("<TD BGCOLOR=" + navColor + " COLSPAN=" + msgSpan +">&nbsp;");
               DoMsgBox(yearmonth, msgSpan);
            } else if (!showMsgBox) {
               document.write("<TD>&nbsp;");
            }
            document.write("</TD>");

         // If the day cell is after the last day of the month, print a miniMonth display of following month in the last cell, 
         // otherwise print a space in this cell of the table.
         } else if (dy > lastdate) {
            if (i == 7) {
               if (showMini) {
                  document.write("<TD BGCOLOR="+ColorBackground+">");   
                  MiniMonth(NextYearMonth(yearmonth));
               } else {
                  document.write("<TD>&nbsp;");
               }
            } else if (showMsgBox && i==(lastday+1)) {   // span empty cells to allow messageBox
               msgSpan = 6 - lastday;
               document.write("<TD BGCOLOR=" + navColor + " COLSPAN=" + msgSpan +">&nbsp;");
               DoMsgBox(yearmonth, msgSpan);
            } else if (!showMsgBox) {
               document.write("<TD>&nbsp;");
            }
            document.write("</TD>");

         // Otherwise, write date and the event, if any, in this cell of the table.
         } else {
            document.write("<TD VALIGN=TOP>");
            ShowDate(yr,mo,dy,i,curmo,curdy);
            document.write("</TD>");            
            dy++;
         }
      }
      document.write("</TR>");
   }

   if (showNav) {
      prev = next = "&nbsp;";
      if (yearmonth > FirstMonth)
         prev = '<a class="navlink" href="' + thispage + '?'+PrevYearMonth(yearmonth)+'">&lt;-- View '+months[PrevMonth(mo)]+'</a>';
      if (yearmonth < LastMonth)
         next += '<a class="navlink" href="' + thispage + '?'+NextYearMonth(yearmonth)+'">View '+months[NextMonth(mo)]+' --&gt;</a>';
      tmp = "<TR BGCOLOR="+navColor+"><TD ALIGN=CENTER BGCOLOR="+navColor+">" + prev + "</TD>";
      tmp += "<TD colspan=5 align=center valign=middle><FORM>";
  //    if (ExportPage) tmp += '<a class="navlink" href="' + ExportPage + '?'+yearmonth+'">Export Events Displayed</a>&nbsp;&nbsp;|&nbsp;&nbsp;';
      tmp += 'Jump to month:&nbsp;&nbsp;';
      document.write(tmp);
      BuildSelectionList(yearmonth, thispage);
      
      if (PrintPage)
        if (FixedLayer=="")
          document.write('&nbsp;&nbsp;|&nbsp;&nbsp;<a class="navlink" href="' + PrintPage + '?'+yearmonth+'">Print-friendly</a>');
        else
          document.write('&nbsp;&nbsp;|&nbsp;&nbsp;<a class="navlink" href="' + PrintPage + '?'+yearmonth+'&FixedLayer=' +FixedLayer+ '">Print-friendly</a>');
          
         
         
      tmp = "</FORM></TD><TD ALIGN=CENTER BGCOLOR="+navColor+">" + next + "</TD>";
      document.write(tmp + "</TR>");
       if (layerCount>2) {
        document.write("<TR BGCOLOR="+navColor+"><TD colspan=7 align=center>");
        ChooseLayers(yearmonth, thispage);
         document.write("</TD></TR>");
      }
   }
   document.write("</TABLE>");
}

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

function ShowDate(yr, mo, dy, dayofweek, currentmonth, currentday) {

   var ind, DayHighlighted, tmp, event;

   tmp = "<TABLE><TR VALIGN=TOP><TD ALIGN=LEFT WIDTH=10%>";
   tmp += "<FONT SIZE=" + DateFontSize;   // Note open tag! 
   DayHighlighted = false;

   if ((mo == currentmonth) && (dy == currentday)) {
      tmp += " COLOR=" + ColorToday;
      DayHighlighted = true;
   } else if (dayofweek == SpecialDay) {
      tmp += " COLOR=" + ColorSpecialDay;
      DayHighlighted = true;
   }

   ind = (((yr * 100) + mo) * 100) + dy;
   if (Events[ind]) {
      //event = Events[ind];
      if (!DayHighlighted) tmp += " COLOR=" + ColorEvent;
// } else {
//    event = "&nbsp;<BR>&nbsp;";
   }
   
   tmp += "><B>" + dy + (dy<10 ? "&nbsp;" : "") + "&nbsp;</B></FONT></TD>";      // close tag
   document.write(tmp);
   
   if (showAltDate) {
      altDate = getAltDate(dy, mo, yr);
      parseFormat(AltDateFormat);
      document.write("<TD ALIGN=RIGHT>" + pre + altDate + post + "</TD>");
   }
   document.write("</TR></TABLE>");

   if (showAltHoly) {
      tmp = getAltHoly(dy,mo,yr);
      if (tmp) {
         parseFormat(AltHolyFormat);
         document.write(pre + tmp + post + "<BR>");
      }
   }
   
   if (showHolidays) {
      tmp = holidays(dy,mo,yr);
      if (tmp) {
         parseFormat(HolidayFormat);
         document.write(pre + tmp + post + "<BR>");
      }
   }
// document.write("<P><FONT SIZE=1>" + event + "</FONT>");

   images=0;
   for (j in Events[ind]) {
      ev = Events[ind][j];
      // with(Events[ind][j]) { // greatly improves readability of following
      //for (k in ev) { alert("ev["+k+"]="+ev[k]) }
      //  document.write("Events[" + ind + "][" + j + "][" + k + "] = " + EscapeLtGt(Events[ind][j][k]), "<br>");
      //alert("-> Layers[Events["+ind+"]["+j+"]."+ev.layer+"].show="+Layers[ev.layer].show);
      tmp = "";      
      if (Layers[ev.layer].show == "true") {
         //alert("(+)showing event for "+ind+" in layer "+ev.layer);
         // Build the HTML string for this event
         tmp += (j>0 ? "<br />" : "");
         if (ev.image && showImages) {
            if (ev.align) {
               align = ev.align;
            } else if (altAlign && images>0) {
               align = (lastAlign=="left" ? "right" : "left");
            } else {
               align = imageAlign;
            }
            tmp += '<img src="' + ev.image + 
                  (ev.width ? '"  width="' + ev.width*imageScale/100 : '') +
                  (ev.height ? '" height="' + ev.height*imageScale/100 : '') +
                  (ev.alt ? '" alt="' + ev.alt : '') +                  
                  '" align="' + align + '" valign="top">';
            lastAlign = align;
            images++;
         }
         format = "";
         if (ev.format == "layer") { // use format from layer (and embedded tags)
            format = Layers[ev.layer].format;
         } else if (ev.format == "custom") { // use only embedded tags
            format = "";
         } else if (ev.format) {    // format string?
            if (CheckFormat(ev.format)) format = ev.format;
         } else if (DefaultFormat == "layer") { // use format from layer if no custom format
            format = Layers[ev.layer].format;
         }
         parseFormat(format);
         //tmp += pre + (ev.link && showLinks ? ev.description.link(ev.link) : ev.description) + post + "<br>";
         tmp += pre + (ev.link && showLinks ? "<a class=\"eventlink\" href="+ev.link+">"+ ev.description + "<br />" + (ev.trs != "" ?  "#" + ev.trs + "<br />" : "") + (ev.instructor != "" ?  ev.instructor + "<br />" : "")  + ev.time +"</a>" : ev.description + "<br />" + (ev.trs != "" ?  "#" + ev.trs + "<br />" : "") + (ev.instructor != "" ?  ev.instructor + "<br />" : "") + ev.time) + post + "<br>";
         
      } else {
         //alert("(-)skipping event for "+ind+" in layer "+ev.layer);
      }
   document.write("<FONT SIZE=1>" + tmp + "</FONT>");
   }
}

function exportCal( ) {
   var curdy, curmo, yr, mo, dy, firstday, yearmonth, lastdate;

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

   initCal(curmo);
   mo = gloMo; yr = gloYr; yearmonth = gloYearmonth;
 //  getLayersVisible();  
   
   // Create a date object for the first day of the desired month
   lastdate = NumDaysIn(mo,yr);

   tmp = "<textarea NAME=\"txt\"  ROWS=20 COLS=75 WRAP=VIRTUAL>";
   tmp += '"Subject","Start Date","Start Time","End Date","End Time","All day event","Description","Show time as","Location"\n';
   document.write(tmp);
   for (dy=1; dy<=lastdate; dy++) {
      ind = (((yr * 100) + mo) * 100) + dy;
      evdate = mo + "/" + dy + "/" + yr;
      for (j in Events[ind]) {
         ev = Events[ind][j];
         if (Layers[ev.layer].show == "true") {
            //alert("(+)showing event for "+ind+" in layer "+ev.layer);
            tmp = qw(ev.description) + "," + qw(evdate) + "," + qw(ev.time.substr(0,ev.time.indexOf("to"))) + "," + qw(evdate) + "," + qw(ev.time.substr(ev.time.indexOf("to") + 3)) + "," + qw("false") + ",," + 
                qw("3") + "," + qw("Quilters Heaven");
            if (ev.description) document.write(tmp+"\n");
         } else {
            //alert("(-)skipping event for "+ind+" in layer "+ev.layer);
         }
      }
   }
   document.write("</textarea>");
}

function getLayersVisible() {
   // get layer visibility settings from cookie
   prefix = cookieName + "|";
   cookie = unescape(document.cookie);
   pos = cookie.indexOf(prefix);
   if (pos>=0) {
       pos += prefix.length;
       sep = cookie.indexOf(";");
       if (sep == -1) sep = cookie.length;
       var layerCookies = cookie.substring(pos, sep).split("|");
       for (i=0; i<layerCookies.length; i++) {
           sep = layerCookies[i].indexOf("=");
      name = layerCookies[i].substring(0, sep);
      value = layerCookies[i].substring(sep+1, layerCookies[i].length);
      if (Layers[name]) Layers[name].show = value;
      //alert("Read cookie: "+name+"="+value+" Layers["+name+"]="+Layers[name].show);
       }
   }
}
function initCal(curmo) {

   // create default layer
   if (!Layers["default"]) DefineLayer("default", DefaultLayerFormat);
 
   // 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;
   }
   gloMo = mo; gloYr = yr; gloYearmonth = yearmonth;
}

function qw(string) {
   return "&quot;" + string + "&quot;";
}

// Create a mini display of the desired month

function MiniMonth(yearmonth) {
   var bgn, firstday, lastdate, miniweek;
   var days = new arr("S","M","T","W","T","F","S");

   mo = yearmonth % 100;
   yr = (yearmonth - mo) / 100;
   bgn = new Date(months[mo] + " 1," + yr);
   // Get the day-of-week of the first day, and the # days in the month
   firstday = bgn.getDay();
   lastdate = NumDaysIn(mo,yr);
   document.write("<b><tt><Font Size=2><div align=center>&nbsp;" + months[mo] + "</div></font>");
   miniweek = "<font size=1>&nbsp;<u>";
   for (d in days) { miniweek += "&nbsp;" + days[d] + "&nbsp;"; }
   document.write(miniweek,"</u>");
   dy = 1;
   // Rest of the weeks . . .
   while (dy <= lastdate) {
      miniweek = "<br>";
      for (var i=1;i<=7;i++) {
         // If the day is less than the day of the week of the first day of the month, append spaces
         if (dy == 1 && i <= firstday){
            miniweek += "&nbsp;&nbsp;&nbsp;";
         // End minimonth if the day > last day of the month
         } else if (dy > lastdate) {
            break;
         // Otherwise, append date (w/ extra space for single digits)
         } else {
            miniweek += "&nbsp;" + ( dy<10 ? "&nbsp;" : "" ) +dy;
            dy++;
         }
      }
      document.write(miniweek);
   }
   document.write("</font></tt></b>");
}


// 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) {
   return ( (yr%4 == 0 && yr%100 != 0) || yr % 400 == 0 ? true : false );
}

// fixes a Netscape 2 and 3 bug
function GetFullYear(d) { // d is a date object
   var yr = d.getYear();
   return ( yr < 1000 ? yr + 1900 : yr );
}

function PrevMonth(mth) {
   return ( mth == 1 ? 12 : mth - 1 );
}

function NextMonth(mth) {
   return ( mth == 12 ? 1 : mth + 1 );
}

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

function NextYearMonth(yrmth) {
   return ( yrmth%100 == 12 ? yrmth-11+100 : 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;
   tmp = "<select name=\"jumpmonth\" size=1 onchange=\"JumpTo(this,'" + thispage + "')\">";
   while (yearmonth <= LastMonth) {
      mo = yearmonth % 100;
      yr = (yearmonth - mo) / 100;
      selected = (yearmonth == current ? " selected" : "");
      tmp += "<option value=" + yearmonth + selected + ">" + months[mo]+" "+yr;
      yearmonth = NextYearMonth(yearmonth);
   }

   document.write(tmp + "</select>");
}

// Create a message box

function DoMsgBox(yearmonth, msgSpan) {
   if (MsgBoxes[yearmonth]) {
      for (j in MsgBoxes[yearmonth]) {    // find first unshown message for month that fits
         monthlyMsg =MsgBoxes[yearmonth][j];
         if (!monthlyMsg.shown) {
            //document.write("monthlyMsg.minspan = " + monthlyMsg.minspan + "<br>");
            if (!monthlyMsg.minspan || monthlyMsg.minspan <= msgSpan) {
               tmp = "<table border=2 bgcolor=" + msgBoxColor + " align=center>";
               tmp += "<TR><TD>"+ monthlyMsg.message + "</TD></TR></table>";
               document.write(tmp);
               monthlyMsg.shown = true;
               return;
            }
         }
      }
   }
   if (MsgBoxes[0]) {   // show default MsgBox messages if they exists
      for (j in MsgBoxes[0]) {   // find first unshown message for month that fits
         monthlyMsg =MsgBoxes[0][j];
         if (!monthlyMsg.shown) {
            //document.write("monthlyMsg.minspan = " + monthlyMsg.minspan + "<br>");
            if (!monthlyMsg.minspan || monthlyMsg.minspan <= msgSpan) {
               tmp = "<table border=2 bgcolor=" + msgBoxColor + " align=center>";
               tmp += "<TR><TD>"+ monthlyMsg.message + "</TD></TR></table>";
               document.write(tmp);
               monthlyMsg.shown = true;
               return;
            }
         }
      }
   }
}

// Utility routines

function escramVal(j,k){var a,b,c,d,e;a='<a href=\"mai';c='\">';a+='lto:';b=j+'@';e='</a>';b+=k;d=b;return(a+b+c+d+e);}

function parseFormat(format) {
   // pre and post are globals
   pre = post = "";
   if (format) {     
      var sep = format.indexOf("|");
      if (sep > 0) {  // split format into pre and post strings
         pre = format.substring(0, sep);
         post= format.substring(1+sep, format.length);
      }
   }
}

function CheckFormat(String) {
   var okay;
   okay =(String == "layer" || String == "custom" || String.indexOf("|")>0);
   if (!okay) alert("Invalid Calendar Format String: " + String);
   return okay;
}
   
// MsgBox constructor
function MsgBox(message,minspan,maxspan) {
   //alert("MsgBox("+message+","+minspan+","+maxspan+")");
   this.message = message;
   this.minspan = (minspan ? minspan : 1);
        if (maxspan) this.maxspan = maxspan;
   //this.shown = false;
}

function AddMsgBox(yearmonth,message,minspan,maxspan) {
   var i;

   if (!MsgBoxes[yearmonth]) MsgBoxes[yearmonth] = new Array;
   i = MsgBoxes[yearmonth].length;
   MsgBoxes[yearmonth][i] = new MsgBox(message,minspan,maxspan);
}

function ChooseLayers(yearmonth, thispage) {
   var i, checked;
   if (FixedLayer == "")
   {
   tmp = '<form name="layerform"><b>Filter Events:</b>&nbsp;';
      for (i in Layers) {
         if (i != "default") {
            checked = (Layers[i].show == "true" ? " checked" : "");
            parseFormat(Layers[i].format);
            tmp += pre + '<input type="checkbox" name="' + i + '" value="' + i + '"' +checked + 
               ' onClick="ChangeLayer(\''+i+'\')">' + i + "&nbsp;" + post;
         }
      }
     // if (layerChange) {
      tmp += '&nbsp;<input type="button" name="ApplyChanges" value="Apply Changes"' +
         'onClick="ApplyLayerChange(\'' + thispage + '\',\'' + yearmonth + '\')">';
     // }
     document.write(tmp + "</form>");
  }
  
}

function ChangeLayer(layer) {
   layerChange=true;
   Layers[layer].show = document.layerform[layer].checked;
}

function ApplyLayerChange(thispage, yearmonth) {
   layerChange=false;
   cookie = cookieName;
   for (layer in Layers) {
      if (layer != "default") {
         cookie += "|" + layer + "=" + Layers[layer].show;
      }
   }
   // persist cookie?
   document.cookie = escape(cookie);
   //alert("set cookie="+cookie);
   document.location = thispage + (yearmonth ? "?"+yearmonth : "");
}