/**
This is a JavaScript library that will allow you to easily add some basic DHTML
drop-down datepicker functionality to your forms.
**/

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

var dayArrayShort = new Array('日', '月', '火', '水', '木', '金', '土');
var dayArrayMed = dayArrayShort;
var dayArrayLong = new Array('日曜日', '月曜日', '火曜日', '水曜日', '木曜日', '金曜日', '土曜日');
var monthArrayShort = new Array('1月', '2月', '3月', '4月', '5月', '6月', '7月', '8月', '9月', '10月', '11月', '12月');
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 monthArrayLong = monthArrayShort;

// these variables define the date formatting we're expecting and outputting.
var defaultDateSeparator = "/";		// common values would be "/" or "."
var defaultDateFormat = "ymd";		// valid values are "mdy", "dmy", and "ymd"
var dateSeparator = defaultDateSeparator;
var dateFormat = defaultDateFormat;

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);
}

/**
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 (!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 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 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 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_title + DIV_title + thisDay.getFullYear() + "年 " + monthArrayLong[ thisDay.getMonth()] + 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 < 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
	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 + "\");'>今月</button> ";
	html += "<button class='dpTodayButton' onClick='updateDateField(\"" + dateFieldName + "\");'>閉じる</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;
}

/**
Update the field with the given dateFieldName with the dateString that has been passed,
and hide the datepicker. If no dateString is passed, just close the datepicker without
changing the field value.
*/
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);
}

/**
Use an "iFrame shim" to deal with problems where the datepicker shows up behind
selection list elements, if they're below the datepicker.
*/
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) {
	}

}