var datePickerDivID = "datepicker";
var iFrameDivID = "datepickeriframe";

var dayArrayShort = new Array('Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat');
var dayArrayMed = new Array('Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat');
var dayArrayLong = new Array('Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday');
var monthArrayShort = new Array('Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec');
var monthArrayMed = new Array('Jan', 'Feb', 'Mar', 'Apr', 'May', 'June', 'July', 'Aug', 'Sept', 'Oct', 'Nov', 'Dec');
var monthArrayLong = new Array('January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December');
 
var defaultDateSeparator = "-";        // common values would be "/" or "."
var defaultDateFormat = "ymd"    // valid values are "mdy", "dmy", and "ymd"
var dateSeparator = defaultDateSeparator;
var dateFormat = defaultDateFormat;


function CopyText(SourceFeild, DestinationFeild) {
	document.getElementsByName (DestinationFeild).item(0).value = document.getElementsByName (SourceFeild).item(0).value;
}

function displayDatePicker(dateFieldName, displayBelowThisObject, dtFormat, dtSep)
{
  var targetDateField = document.getElementsByName(dateFieldName).item(0);
 
  // if we weren't told what node to display the datepicker beneath, just display it
  // beneath the date field we're updating
  if (!displayBelowThisObject)
	displayBelowThisObject = targetDateField;
 
  // if a date separator character was given, update the dateSeparator variable
  if (dtSep)
	dateSeparator = dtSep;
  else
	dateSeparator = defaultDateSeparator;
 
  // if a date format was given, update the dateFormat variable
  if (dtFormat)
	dateFormat = dtFormat;
  else
	dateFormat = defaultDateFormat;
 
  var x = displayBelowThisObject.offsetLeft;
  var y = displayBelowThisObject.offsetTop + displayBelowThisObject.offsetHeight ;
 
  // deal with elements inside tables and such
  var parent = displayBelowThisObject;
  while (parent.offsetParent) {
	parent = parent.offsetParent;
	x += parent.offsetLeft;
	y += parent.offsetTop ;
  }
 
  drawDatePicker(targetDateField, x, y);
}


function drawDatePicker(targetDateField, x, y)
{
  var dt = getFieldDate(targetDateField.value);
 
  // the datepicker table will be drawn inside of a <div> with an ID defined by the
  // global datePickerDivID variable. If such a div doesn't yet exist on the HTML
  // document we're working with, add one.
  if (!document.getElementById(datePickerDivID)) {
	// don't use innerHTML to update the body, because it can cause global variables
	// that are currently pointing to objects on the page to have bad references
	//document.body.innerHTML += "<div id='" + datePickerDivID + "' class='dpDiv'></div>";
	var newNode = document.createElement("div");
	newNode.setAttribute("id", datePickerDivID);
	newNode.setAttribute("class", "dpDiv");
	newNode.setAttribute("style", "visibility: hidden;");
	document.body.appendChild(newNode);
  }
 
  // move the datepicker div to the proper x,y coordinate and toggle the visiblity
  var pickerDiv = document.getElementById(datePickerDivID);
  pickerDiv.style.position = "absolute";
  pickerDiv.style.left = x + "px";
  pickerDiv.style.top = y + "px";
  pickerDiv.style.visibility = (pickerDiv.style.visibility == "visible" ? "hidden" : "visible");
  pickerDiv.style.display = (pickerDiv.style.display == "block" ? "none" : "block");
  pickerDiv.style.zIndex = 10000;
 
  // draw the datepicker table
  refreshDatePicker(targetDateField.name, dt.getFullYear(), dt.getMonth(), dt.getDate());
}


/**
This is the function that actually draws the datepicker calendar.
*/
function refreshDatePicker(dateFieldName, year, month, day)
{
  // if no arguments are passed, use today's date; otherwise, month and year
  // are required (if a day is passed, it will be highlighted later)
  var thisDay = new Date();
 
  if ((month >= 0) && (year > 0)) {
	thisDay = new Date(year, month, 1);
  } else {
	day = thisDay.getDate();
	thisDay.setDate(1);
  }
 
  // the calendar will be drawn as a table
  // you can customize the table elements with a global CSS style sheet,
  // or by hardcoding style and formatting elements below
  var crlf = "\r\n";
  var TABLE = "<table cols=7 class='dpTable'>" + crlf;
  var xTABLE = "</table>" + crlf;
  var TR = "<tr class='dpTR'>";
  var TR_title = "<tr class='dpTitleTR'>";
  var TR_days = "<tr class='dpDayTR'>";
  var TR_todaybutton = "<tr class='dpTodayButtonTR'>";
  var xTR = "</tr>" + crlf;
  var TD = "<td nowrap class='dpTD' onMouseOut='this.className=\"dpTD\";' onMouseOver=' this.className=\"dpTDHover\";' ";    // leave this tag open, because we'll be adding an onClick event
  var TD_title = "<td  nowrap colspan=5 class='dpTitleTD'>";
  var TD_buttons = "<td  nowrap class='dpButtonTD'>";
  var TD_todaybutton = "<td  nowrap colspan=7 class='dpTodayButtonTD'>";
  var TD_days = "<td class='dpDayTD'>";
  var TD_selected = "<td class='dpDayHighlightTD' onMouseOut='this.className=\"dpDayHighlightTD\";' onMouseOver='this.className=\"dpTDHover\";' ";    // leave this tag open, because we'll be adding an onClick event
  var xTD = "</td>" + crlf;
  var DIV_title = "<div class='dpTitleText'>";
  var DIV_selected = "<div class='dpDayHighlight'>";
  var xDIV = "</div>";
 
  // start generating the code for the calendar table
  var html = TABLE;
 
  // this is the title bar, which displays the month and the buttons to
  // go back to a previous month or forward to the next month
  html += TR_title;
  html += TD_buttons + getButtonCode(dateFieldName, thisDay, -1, "&lt;") + xTD;
  html += TD_title + DIV_title + monthArrayLong[ thisDay.getMonth()] + " " + thisDay.getFullYear() + xDIV + xTD;
  html += TD_buttons + getButtonCode(dateFieldName, thisDay, 1, "&gt;") + xTD;
  html += xTR;
 
  // this is the row that indicates which day of the week we're on
  html += TR_days;
  for(i = 0; i < dayArrayMed.length; i++)
	html += TD_days + dayArrayMed[i] + xTD;
  html += xTR;
 
  // now we'll start populating the table with days of the month
  html += TR;
 
  // first, the leading blanks
  for (i = 0; i < thisDay.getDay(); i++)
	html += TD + "&nbsp;" + xTD;
 
  // now, the days of the month
  do {
	dayNum = thisDay.getDate();
	TD_onclick = " onclick=\"updateDateField('" + dateFieldName + "', '" + getDateString(thisDay) + "');\">";
	
	if (dayNum == day)
	  html += TD_selected + TD_onclick + DIV_selected + dayNum + xDIV + xTD;
	else
	  html += TD + TD_onclick + dayNum + xTD;
	
	// if this is a Saturday, start a new row
	if (thisDay.getDay() == 6)
	  html += xTR + TR;
	
	// increment the day
	thisDay.setDate(thisDay.getDate() + 1);
  } while (thisDay.getDate() > 1)
 
  // fill in any trailing blanks
  if (thisDay.getDay() > 0) {
	for (i = 6; i > thisDay.getDay(); i--)
	  html += TD + "&nbsp;" + xTD;
  }
  html += xTR;
 
  // add a button to allow the user to easily return to today, or close the calendar
  var today = new Date();
  var todayString = "Today is " + dayArrayMed[today.getDay()] + ", " + monthArrayMed[ today.getMonth()] + " " + today.getDate();
  html += TR_todaybutton + TD_todaybutton;
  html += "<button class='dpTodayButton' onClick='refreshDatePicker(\"" + dateFieldName + "\");'>This Month</button> ";
  html += xTD + xTR;
 
  // and finally, close the table
  html += xTABLE;
 
  document.getElementById(datePickerDivID).innerHTML = html;
  // add an "iFrame shim" to allow the datepicker to display above selection lists
  adjustiFrame();
}


/**
Convenience function for writing the code for the buttons that bring us back or forward
a month.
*/
function getButtonCode(dateFieldName, dateVal, adjust, label)
{
  var newMonth = (dateVal.getMonth () + adjust) % 12;
  var newYear = dateVal.getFullYear() + parseInt((dateVal.getMonth() + adjust) / 12);
  if (newMonth < 0) {
	newMonth += 12;
	newYear += -1;
  }
 
  return "<button class='dpButton' onClick='refreshDatePicker(\"" + dateFieldName + "\", " + newYear + ", " + newMonth + ");'>" + label + "</button>";
}


/**
Convert a JavaScript Date object to a string, based on the dateFormat and dateSeparator
variables at the beginning of this script library.
*/
function getDateString(dateVal)
{
  var dayString = "00" + dateVal.getDate();
  var monthString = "00" + (dateVal.getMonth()+1);
  dayString = dayString.substring(dayString.length - 2);
  monthString = monthString.substring(monthString.length - 2);
 
  switch (dateFormat) {
	case "dmy" :
	  return dayString + dateSeparator + monthString + dateSeparator + dateVal.getFullYear();
	case "ymd" :
	  return dateVal.getFullYear() + dateSeparator + monthString + dateSeparator + dayString;
	case "mdy" :
	default :
	  return monthString + dateSeparator + dayString + dateSeparator + dateVal.getFullYear();
  }
}


/**
Convert a string to a JavaScript Date object.
*/
function getFieldDate(dateString)
{
  var dateVal;
  var dArray;
  var d, m, y;
 
  try {
	dArray = splitDateString(dateString);
	if (dArray) {
	  switch (dateFormat) {
		case "dmy" :
		  d = parseInt(dArray[0], 10);
		  m = parseInt(dArray[1], 10) - 1;
		  y = parseInt(dArray[2], 10);
		  break;
		case "ymd" :
		  d = parseInt(dArray[2], 10);
		  m = parseInt(dArray[1], 10) - 1;
		  y = parseInt(dArray[0], 10);
		  break;
		case "mdy" :
		default :
		  d = parseInt(dArray[1], 10);
		  m = parseInt(dArray[0], 10) - 1;
		  y = parseInt(dArray[2], 10);
		  break;
	  }
	  dateVal = new Date(y, m, d);
	} else if (dateString) {
	  dateVal = new Date(dateString);
	} else {
	  dateVal = new Date();
	}
  } catch(e) {
	dateVal = new Date();
  }
 
  return dateVal;
}


/**
Try to split a date string into an array of elements, using common date separators.
If the date is split, an array is returned; otherwise, we just return false.
*/
function splitDateString(dateString)
{
  var dArray;
  if (dateString.indexOf("/") >= 0)
	dArray = dateString.split("/");
  else if (dateString.indexOf(".") >= 0)
	dArray = dateString.split(".");
  else if (dateString.indexOf("-") >= 0)
	dArray = dateString.split("-");
  else if (dateString.indexOf("\\") >= 0)
	dArray = dateString.split("\\");
  else
	dArray = false;
 
  return dArray;
}


function updateDateField(dateFieldName, dateString)
{
  var targetDateField = document.getElementsByName (dateFieldName).item(0);
  if (dateString)
	targetDateField.value = dateString;
 
  var pickerDiv = document.getElementById(datePickerDivID);
  pickerDiv.style.visibility = "hidden";
  pickerDiv.style.display = "none";
 
  adjustiFrame();
  targetDateField.focus();
 
  // after the datepicker has closed, optionally run a user-defined function called
  // datePickerClosed, passing the field that was just updated as a parameter
  // (note that this will only run if the user actually selected a date from the datepicker)
  if ((dateString) && (typeof(datePickerClosed) == "function"))
	datePickerClosed(targetDateField);
}



function adjustiFrame(pickerDiv, iFrameDiv)
{
  // we know that Opera doesn't like something about this, so if we
  // think we're using Opera, don't even try
  var is_opera = (navigator.userAgent.toLowerCase().indexOf("opera") != -1);
  if (is_opera)
	return;
  
  // put a try/catch block around the whole thing, just in case
  try {
	if (!document.getElementById(iFrameDivID)) {
	  // don't use innerHTML to update the body, because it can cause global variables
	  // that are currently pointing to objects on the page to have bad references
	  //document.body.innerHTML += "<iframe id='" + iFrameDivID + "' src='javascript:false;' scrolling='no' frameborder='0'>";
	  var newNode = document.createElement("iFrame");
	  newNode.setAttribute("id", iFrameDivID);
	  newNode.setAttribute("src", "javascript:false;");
	  newNode.setAttribute("scrolling", "no");
	  newNode.setAttribute ("frameborder", "0");
	  document.body.appendChild(newNode);
	}
	
	if (!pickerDiv)
	  pickerDiv = document.getElementById(datePickerDivID);
	if (!iFrameDiv)
	  iFrameDiv = document.getElementById(iFrameDivID);
	
	try {
	  iFrameDiv.style.position = "absolute";
	  iFrameDiv.style.width = pickerDiv.offsetWidth;
	  iFrameDiv.style.height = pickerDiv.offsetHeight ;
	  iFrameDiv.style.top = pickerDiv.style.top;
	  iFrameDiv.style.left = pickerDiv.style.left;
	  iFrameDiv.style.zIndex = pickerDiv.style.zIndex - 1;
	  iFrameDiv.style.visibility = pickerDiv.style.visibility ;
	  iFrameDiv.style.display = pickerDiv.style.display;
	} catch(e) {
	}
 
  } catch (ee) {
  }
 
}