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

var dayArrayShort = new Array('一', '二', '三', '四', '五', '六', '日');
var dayArrayMed = new Array('一', '二', '三', '四', '五', '六', '日');
var dayArrayLong = new Array('一', '二', '三', '四', '五', '六', '日');
var monthArrayShort = new Array('一月', '二月', '三月', '四月', '五月', '六月', '七月', '八月', '九月', '十月', '十一月', '十二月');
var monthArrayMed = new Array('一月', '二月', '三月', '四月', '五月', '六月', '七月', '八月', '九月', '十月', '十一月', '十二月');
var monthArrayLong = new Array('一月', '二月', '三月', '四月', '五月', '六月', '七月', '八月', '九月', '十月', '十一月', '十二月');
 
// these variables define the date formatting we're expecting and outputting.
// If you want to use a different format by default, change the defaultDateSeparator
// and defaultDateFormat variables either here or on your HTML page.
var defaultDateSeparator = "/";        // common values would be "/" or "."
var defaultDateFormat = "dmy"    // valid values are "mdy", "dmy", and "ymd"
var dateSeparator = defaultDateSeparator;
var dateFormat = defaultDateFormat;
var closeMethodTrigger = false;

var fromDaysLimit = 0;
var toDaysLimit = 0;

var limitDate;
var limitDay = 0;
var limitMonth = 0;
var limitYear = 0;

function displayDatePicker(dateFieldName, closeTrigger, displayBelowThisObject, dtFormat, dtSep, fromDay, toDay){
	var targetDateField = document.getElementsByName (dateFieldName).item(0);
	closeMethodTrigger = closeTrigger;
	
	// 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 ;
	}
   
	if((fromDay != null) && (fromDay > 0))
		fromDaysLimit = fromDay;
  
	if((toDay != null) && (toDay > 0)){
		toDaysLimit = toDay;
		
		limitDate = new Date();
		limitDate.setDate(limitDate.getDate() + toDaysLimit);
		limitDay = limitDate.getDate();
		limitMonth = limitDate.getMonth();
		limitYear = limitDate.getFullYear();
	}
   
   	drawDatePicker(targetDateField, x, y);
}


/**
Draw the datepicker object (which is just a table with calendar elements) at the
specified x and y coordinates, using the targetDateField object as the input tag
that will ultimately be populated with a date.

This function will normally be called by the displayDatePicker function.
*/
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.setAttribute("class", "dpDiv");
	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_months = "<tr class='dpMonthTR'><td colspan=7>";
	var TR_todaybutton = "<tr class='dpTodayButtonTR'>";
	var xTR = "</tr>" + crlf;
	var TD = "<td class='dpTD' onMouseOut='this.className=\"dpTD\";' onMouseOver=' this.className=\"dpTDHover\";' ";    // leave this tag open, because we'll be adding an onClick event
	var TD_disabled = "<td class='dpTD dpTDDisabled' >";
	var TD_title = "<td colspan=5 class='dpTitleTD'>";
	var TD_buttons = "<td class='dpButtonTD'>";
	var TD_todaybutton = "<td 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 DIV_month = "<div class='dpMonths'>";
	var xDIV = "</div>";
	
	var SPAN_Item = "<span class='dpMonthItem'>";
	var xSPAN = "</span>";
	
	
	// 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;&lt;") + xTD;
	html += TD_title + DIV_title + monthArrayLong[ thisDay.getMonth()] + " " + thisDay.getFullYear() + xDIV + xTD;
	html += TD_buttons + getButtonCode(dateFieldName, thisDay, 1, "&gt;&gt;") + xTD;
	html += xTD + xTR;
 
 
 	// --- populate the months ---
	html += TR_months;
	html += DIV_month;
	
		var currentMonth = thisDay.getMonth();
		for(var m = 0; m < 5; ++m){
			// monthArrayMed
			currentMonth += 1;
			
			if(currentMonth == 12)
				currentMonth = 0;
			
			html += SPAN_Item + getButtonCode(dateFieldName, thisDay, m+1, monthArrayShort[currentMonth], false) + xSPAN;
		}
	
	html += xDIV;
 	html += xTR;
	
	
	// this is the row that indicates which day of the week we're on
	html += TR_days;
	for(i = 0; i < dayArrayShort.length; i++)
		html += TD_days + dayArrayShort[i] + xTD;
	html += xTR;
	
	// now we'll start populating the table with days of the month
	html += TR;
	
	// first, the leading blanks
	if( thisDay.getDay() == 0 ){
		for (i = 1; i < 7; i++)
			html += TD + "&nbsp;" + xTD;	
	}
	else{
		for (i = 1; 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) + "');\">";
	
		var todayDate = new Date();
	
		if(fromDaysLimit != 0)
			todayDate.setDate(todayDate.getDate() + fromDaysLimit);
		
		var todayDay = todayDate.getDate();
		var todayMonth = todayDate.getMonth();
		var todayYear = todayDate.getFullYear();
		
		
		if (dayNum == day){
			// --- NEW ADDED ---
			if(fromDaysLimit != 0)
				html += TD_disabled + DIV_selected + dayNum + xDIV + xTD;
			else
				html += TD_selected + TD_onclick + DIV_selected + dayNum + xDIV + xTD;
		}
		else { 
/* -------------------------------------------------------------------------------- */			
			// --- Check if there's any limit ---			
			if(limitYear > 0){
				// --- If limit is within the same year ---
				if(limitYear == year){
					// --- For those within the same year ---
					if(todayYear == year){
						if((limitMonth > month) && (todayMonth < month)){
							html += TD + TD_onclick + dayNum + xTD;
						}
						else if(limitMonth == month){
							if(todayMonth == month){
								if ((dayNum <= limitDay) && (dayNum >= todayDay))
									html += TD + TD_onclick + dayNum + xTD;	
								else
									html += TD_disabled + dayNum + xTD;
							}
							else {
								if(dayNum <= limitDay)
									html += TD + TD_onclick + dayNum + xTD;	
								else
									html += TD_disabled + dayNum + xTD;
							}
						}
						else if(todayMonth == month){
							if(dayNum >= todayDay)
								html += TD + TD_onclick + dayNum + xTD;	
							else
								html += TD_disabled + dayNum + xTD;
						}
						else
							html += TD_disabled + dayNum + xTD;
					}
					else if(limitMonth == month){
						if (dayNum > limitDay)
							html += TD_disabled + dayNum + xTD;
						else
							html += TD + TD_onclick + dayNum + xTD;	
					}
					else if(limitMonth >= month)
						html += TD + TD_onclick + dayNum + xTD;	
					else
						html += TD_disabled + dayNum + xTD;
					

				}
				// --- If limit later then current year ---
				else if(limitYear > year){
					// --- For those within the same year ---
					if(todayYear == year){
						// --- check if from limit month is of the same month ---
						if(todayMonth == month){
							if (dayNum >= todayDay)
								html += TD + TD_onclick + dayNum + xTD;	
							else
								html += TD_disabled + dayNum + xTD;
						}
						// --- if not same month ---
						else if(todayMonth < month)
							html += TD + TD_onclick + dayNum + xTD;	
						else
							html += TD_disabled + dayNum + xTD;
					}
					// --- For those later then current year ---
					else if(todayYear < year)
						html += TD + TD_onclick + dayNum + xTD;
					else
						html += TD_disabled + dayNum + xTD;

				}
				else{
					html += TD_disabled + dayNum + xTD;
				}
				
			}
			// --- No Limit ---
			else{
				// --- For those within the same year ---
				if(todayYear == year){
					if(todayMonth == month){
						if (dayNum < todayDay)
							html += TD_disabled + dayNum + xTD;
						else
							html += TD + TD_onclick + dayNum + xTD;	
					}else if(todayMonth < month)
						html += TD + TD_onclick + dayNum + xTD;
					else
						html += TD_disabled + dayNum + xTD;
				}
				// --- For those later then current year ---
				else if(todayYear < year)
					html += TD + TD_onclick + dayNum + xTD;
				else
					html += TD_disabled + dayNum + xTD;
			}
/* -------------------------------------------------------------------------------- */

		}
	
    // if this is a Saturday, start a new row
    if (thisDay.getDay() == 0)
      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 += "<button class='dpTodayButton' onClick='updateDateField(\"" + dateFieldName + "\");'>close</button>";
  html += "<a class='dptxtButton' onClick='updateDateField(\"" + dateFieldName + "\");'>关闭</a>";
  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
  
	if (window.XMLHttpRequest) {
		// DO nothing
	} else {
  		adjustiFrame();
	}
	
}


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



/**
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);
 
  var dateTrack = dateVal.getDay();
  var dateList = new Array("日","一","二","三","四","五","六");
 
  switch (dateFormat) {
    case "dmy" :
      return dayString + dateSeparator + monthString + dateSeparator + dateVal.getFullYear() + " " + dateList[dateTrack];
    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";
 
 	if (window.XMLHttpRequest) {
  		// DO nothing
	} else {
		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(closeMethodTrigger){
  	if ((dateString) && (typeof(datePickerClosed) == "function"))
    	datePickerClosed(targetDateField);
  }
}


/**
Use an "iFrame shim" to deal with problems where the datepicker shows up behind
selection list elements, if they're below the datepicker. The problem and solution are
described at:

http://dotnetjunkies.com/WebLog/jking/archive/2003/07/21/488.aspx
http://dotnetjunkies.com/WebLog/jking/archive/2003/10/30/2975.aspx
*/
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) {
  }
 
}