//
// JavaScript Calendar Component
// Author: Robert W. Husted  (robert.husted@iname.com)
// Date:   8/22/1999
// Modified Date: 11/30/1999
// Modified By:   Robert W. Husted
// Modified Date: 15.10.2002
// Modified By:   Nico van Vliet
// Modified Date: 25.07.2006
// Modified By:   Robert Scholte
// Modification: rewrite from popup to innerhtml. Only use js when really required   

//Rien
calDateFormat = 'dd-mm-yyyy';
firstDay = 6; //saturday=6

// END USER-EDITABLE SECTION -------------------------------------------------------


// DETERMINE BROWSER BRAND
var isNav = false;
var isIE  = false;

// ASSUME IT'S EITHER NETSCAPE OR MSIE
if (navigator.appName == 'Netscape') 
{
    isNav = true;
}
else 
{
    isIE = true;
}

// GET CURRENTLY SELECTED LANGUAGE
//selectedLanguage = navigator.language;
//Rien
selectedLanguage = 'nl';

// PRE-BUILD PORTIONS OF THE CALENDAR WHEN THIS JS LIBRARY LOADS INTO THE BROWSER
buildCalParts();

setInitialDate();

// CALENDAR FUNCTIONS BEGIN HERE ---------------------------------------------------

// SET THE INITIAL VALUE OF THE GLOBAL DATE FIELD
function setDateField(dateField) 
{
    // ASSIGN THE INCOMING FIELD OBJECT TO A GLOBAL VARIABLE
    calDateField = dateField;

    // GET THE VALUE OF THE INCOMING FIELD
    inDate = dateField.value;

    // SET calDate TO THE DATE IN THE INCOMING FIELD OR DEFAULT TO TODAY'S DATE
    setInitialDate();

    // THE CALENDAR FRAMESET DOCUMENTS ARE CREATED BY JAVASCRIPT FUNCTIONS
    calDocTop    = buildTopCalFrame();
    calDocBottom = buildBottomCalFrame();
}


// SET THE INITIAL CALENDAR DATE TO TODAY OR TO THE EXISTING VALUE IN dateField
function setInitialDate() 
{
	//force an initialized inDate
	var inDate = inDate || '';
   
    // CREATE A NEW DATE OBJECT (WILL GENERALLY PARSE CORRECT DATE EXCEPT WHEN "." IS USED AS A DELIMITER)
    // (THIS ROUTINE DOES *NOT* CATCH ALL DATE FORMATS, IF YOU NEED TO PARSE A CUSTOM DATE FORMAT, DO IT HERE)
    var cSeparator = '-';
    var dIndex = 0;
    var mIndex = inDate.indexOf(cSeparator);
    var yIndex = inDate.indexOf(cSeparator,mIndex + 1);
    var day = inDate.substring(dIndex,mIndex);
    var month = inDate.substring(mIndex + 1,yIndex);
    var year = inDate.substring(yIndex + 1);
    var myDate = month + '/' + day + '/' + year;

    calDate = new Date(myDate);

    // IF THE INCOMING DATE IS INVALID, USE THE CURRENT DATE
    if (isNaN(calDate)) 
	{
        // ADD CUSTOM DATE PARSING HERE
        // IF IT FAILS, SIMPLY CREATE A NEW DATE OBJECT WHICH DEFAULTS TO THE CURRENT DATE
        calDate = new Date();
    }

    // KEEP TRACK OF THE CURRENT DAY VALUE
    calDay  = calDate.getDate();

    // SET DAY VALUE TO 1... TO AVOID JAVASCRIPT DATE CALCULATION ANOMALIES
    // (IF THE MONTH CHANGES TO FEB AND THE DAY IS 30, THE MONTH WOULD CHANGE TO MARCH
    //  AND THE DAY WOULD CHANGE TO 2.  SETTING THE DAY TO 1 WILL PREVENT THAT)
    calDate.setDate(1);
}

// CREATE THE BOTTOM CALENDAR FRAME 
// (THE MONTHLY CALENDAR)
function buildBottomCalFrame() 
{
    // START CALENDAR DOCUMENT
    var calDoc = calendarBegin;

    // GET MONTH, AND YEAR FROM GLOBAL CALENDAR DATE
    month   = calDate.getMonth();
    year    = calDate.getFullYear();


    // GET GLOBALLY-TRACKED DAY VALUE (PREVENTS JAVASCRIPT DATE ANOMALIES)
    day     = calDay;

    var i   = 0;

    // DETERMINE THE NUMBER OF DAYS IN THE CURRENT MONTH
    var days = getDaysInMonth();

    // IF GLOBAL DAY VALUE IS > THAN DAYS IN MONTH, HIGHLIGHT LAST DAY IN MONTH
    if (day > days) 
	{
        day = days;
    }

    // DETERMINE WHAT DAY OF THE WEEK THE CALENDAR STARTS ON
    var firstOfMonth = new Date (year, month, 1);

    // GET THE DAY OF THE WEEK THE FIRST DAY OF THE MONTH FALLS ON
    //var startingPos  = firstOfMonth.getDay();
    var startingPos  = (7 + firstOfMonth.getDay() - firstDay) %7;
    days += startingPos;

    // KEEP TRACK OF THE COLUMNS, START A NEW ROW AFTER EVERY 7 COLUMNS
    var columnCount = 0;

    // MAKE BEGINNING NON-DATE CELLS BLANK
    for (i = 0; i < startingPos; i++) 
	{
        calDoc += blankCell;
		columnCount++;
    }

    // SET VALUES FOR DAYS OF THE MONTH
    var currentDay = 0;
//    var dayType    = "weekDay";
    var dayType    = 'focusDay';

    // DATE CELLS CONTAIN A NUMBER
    for (i = startingPos; i < days; i++) 
	{
        // ADJUST SPACING SO THAT ALL LINKS HAVE RELATIVELY EQUAL WIDTHS
        if (i-startingPos+1 < 10) 
		{
            padding = '&nbsp;';
        }
        else 
		{
            padding = '';
        }

        // GET THE DAY CURRENTLY BEING WRITTEN
        currentDay = i-startingPos + 1;
        
        var realDate = new Date();

        // SET THE TYPE OF DAY, THE focusDay GENERALLY APPEARS AS A DIFFERENT COLOR
        if (currentDay == day && realDate.getMonth() == month && realDate.getYear() == year) 
		{
            dayType = 'focusDay';
        }
        else 
		{
            dayType = 'weekDay';
        }

        // ADD THE DAY TO THE CALENDAR STRING
        calDoc += '<td>' +
                  "<a class='" + dayType + "' href='javascript:returnDate(this," + 
                  currentDay + ")'>" + padding + currentDay +
                  '</a></td>';

        columnCount++;

        // START A NEW ROW WHEN NECESSARY
        if (columnCount % 7 == 0) 
		{
            calDoc += "</TR><TR>";
        }
    }

    // MAKE REMAINING NON-DATE CELLS BLANK
    for (;columnCount % 7 > 0; columnCount++)  {
        calDoc += blankCell;
    }
		calDoc += "</TR>";

    // FINISH THE NEW CALENDAR PAGE
    calDoc += calendarEnd;

    // RETURN THE COMPLETED CALENDAR PAGE
    return calDoc;
}


// WRITE THE MONTHLY CALENDAR TO THE BOTTOM CALENDAR FRAME
function writeCalendar() {
		calBottom = document.getElementById("bottomCal"); //@TODO now only one instance per page accepted

    // CREATE THE NEW CALENDAR FOR THE SELECTED MONTH & YEAR
    calDocBottom = buildBottomCalFrame();

    // WRITE THE NEW CALENDAR TO THE BOTTOM FRAME
    calBottom.innerHTML = calDocBottom;
}


// SET THE CALENDAR TO TODAY'S DATE AND DISPLAY THE NEW CALENDAR
function setToday(elm) {

    // SET GLOBAL DATE TO TODAY'S DATE
    calDate = new Date();

    // SET DAY MONTH AND YEAR TO TODAY'S DATE
    var month = calDate.getMonth();
    var year  = calDate.getFullYear();

    // SET MONTH IN DROP-DOWN LIST
    elm.form.month0.selectedIndex = month;

    // SET YEAR VALUE
    elm.form.year0.value = year;

    // DISPLAY THE NEW CALENDAR
    writeCalendar();
}

// SET THE GLOBAL DATE TO THE NEWLY ENTERED YEAR AND REDRAW THE CALENDAR
function setYear(elm) {

    // GET THE NEW YEAR VALUE
    var year  = elm.form.year0.value;

    // IF IT'S A FOUR-DIGIT YEAR THEN CHANGE THE CALENDAR
    if (isFourDigitYear(year, elm)) {
        calDate.setFullYear(year);
        writeCalendar();
    }
    else {
        // HIGHLIGHT THE YEAR IF THE YEAR IS NOT FOUR DIGITS IN LENGTH
        elm.form.year0.focus();
        elm.form.year0.select();
    }
}


// SET THE GLOBAL DATE TO THE SELECTED MONTH AND REDRAW THE CALENDAR
function setCurrentMonth(elm) {

    // GET THE NEWLY SELECTED MONTH AND CHANGE THE CALENDAR ACCORDINGLY
    var month = elm.form.month0.selectedIndex;

    calDate.setMonth(month);
    writeCalendar();
}


// SET THE GLOBAL DATE TO THE PREVIOUS YEAR AND REDRAW THE CALENDAR
function setPreviousYear(elm) {

    var year  = elm.form.year0.value;

    if (isFourDigitYear(year, elm) && year > 1000) {
        year--;
        calDate.setFullYear(year);
        elm.form.year0.value = year;
        writeCalendar();
    }
}


// SET THE GLOBAL DATE TO THE PREVIOUS MONTH AND REDRAW THE CALENDAR
function setPreviousMonth(elm) {

    var year  = elm.form.year0.value;
    if (isFourDigitYear(year, elm)) {
        var month = elm.form.month0.selectedIndex;

        // IF MONTH IS JANUARY, SET MONTH TO DECEMBER AND DECREMENT THE YEAR
        if (month == 0) {
            month = 11;
            if (year > 1000) {
                year--;
                calDate.setFullYear(year);
                elm.form.year0.value = year;
            }
        }
        else {
            month--;
        }
        calDate.setMonth(month);
        elm.form.month0.selectedIndex = month;
        writeCalendar();
    }
}


// SET THE GLOBAL DATE TO THE NEXT MONTH AND REDRAW THE CALENDAR
function setNextMonth(elm) {

    var year = elm.form.year0.value;

    if (isFourDigitYear(year, elm)) {
        var month = elm.form.month0.selectedIndex;

        // IF MONTH IS DECEMBER, SET MONTH TO JANUARY AND INCREMENT THE YEAR
        if (month == 11) {
            month = 0;
            year++;
            calDate.setFullYear(year);
            elm.form.year0.value = year;
        }
        else {
            month++;
        }
        calDate.setMonth(month);
        elm.form.month0.selectedIndex = month;
        writeCalendar();
    }
}


// SET THE GLOBAL DATE TO THE NEXT YEAR AND REDRAW THE CALENDAR
function setNextYear(elm) {

    var year  = elm.form.year0.value;
    if (isFourDigitYear(year, elm)) {
        year++;
        calDate.setFullYear(year);
        elm.form.year0.value = year;
        writeCalendar();
    }
}


// GET NUMBER OF DAYS IN MONTH
function getDaysInMonth()  {

    var days;
    var month = calDate.getMonth()+1;
    var year  = calDate.getFullYear();

    // RETURN 31 DAYS
    if (month==1 || month==3 || month==5 || month==7 || month==8 ||
        month==10 || month==12)  {
        days=31;
    }
    // RETURN 30 DAYS
    else if (month==4 || month==6 || month==9 || month==11) {
        days=30;
    }
    // RETURN 29 DAYS
    else if (month==2)  {
        if (isLeapYear(year)) {
            days=29;
        }
        // RETURN 28 DAYS
        else {
            days=28;
        }
    }
    return (days);
}


// CHECK TO SEE IF YEAR IS A LEAP YEAR
function isLeapYear (Year) {

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


// ENSURE THAT THE YEAR IS FOUR DIGITS IN LENGTH
function isFourDigitYear(year, elm) {

    if (year.length != 4) {
        elm.form.year0.value = calDate.getFullYear();
        elm.form.year0.select();
        elm.form.year0.focus();
    }
    else {
        return true;
    }
}


// BUILD THE MONTH SELECT LIST
function getMonthsList() {

    // IF DUTCH
    if (selectedLanguage == "nl") {
        monthArray = new Array('Januari', 'Februari', 'Maart', 'April', 'Mei', 'Juni',
                               'Juli', 'Augustus', 'September', 'Oktober', 'November', 'December');
    }
    // DEFAULT TO ENGLISH
    else {
        monthArray = new Array('January', 'February', 'March', 'April', 'May', 'June',
                               'July', 'August', 'September', 'October', 'November', 'December');
    }
    return monthArray;
}


// SET DAYS OF THE WEEK DEPENDING ON LANGUAGE
function createWeekdayList() {

    // IF DUTCH
    if (selectedLanguage == "nl") {
        weekdayList  = new Array('Zondag', 'Maandag', 'Dinsdag', 'Woensdag', 'Donderdag', 'Vrijdag', 'Zaterdag');
        weekdayArray = new Array('Zo', 'Ma', 'Di', 'Wo', 'Do', 'Vr', 'Za');
    }
    else {
        weekdayList  = new Array('Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday');
        weekdayArray = new Array('Su','Mo','Tu','We','Th','Fr','Sa');
    }

    var weekdays = "<tr>";

    for (i=0;i<weekdayArray.length;i++) {
        weekdays += "<th>" + weekdayArray[(firstDay + i)%7] + "</th>";
    }
    weekdays += "</tr>";

    return weekdays;
}


// PRE-BUILD PORTIONS OF THE CALENDAR (FOR PERFORMANCE REASONS)
function buildCalParts() {

    // GENERATE WEEKDAY HEADERS FOR THE CALENDAR
    weekdays = createWeekdayList();

    // BUILD THE BLANK CELL ROWS
    blankCell = "<td>&nbsp;</td>";

    // BUILD THE TOP PORTION OF THE CALENDAR PAGE USING CSS TO CONTROL SOME DISPLAY ELEMENTS
    calendarBegin = ""

        // NAVIGATOR NEEDS A TABLE CONTAINER TO DISPLAY THE TABLE OUTLINES PROPERLY
        if (isNav) {
            calendarBegin += 
                "<table><TR><TD>";
        }

        // BUILD WEEKDAY HEADINGS
        calendarBegin +=
            "<table><thead>" +
            weekdays +
            "</thead><tbody>";


    // BUILD THE BOTTOM PORTION OF THE CALENDAR PAGE
    calendarEnd = "</tbody></table>";

        // NAVIGATOR NEEDS A TABLE CONTAINER TO DISPLAY THE BORDERS PROPERLY
        if (isNav) {
            calendarEnd += "</TD></TR></TABLE>";
        }
}

function jsReplace(inString, find, replace) {

    var outString = "";

    if (!inString) {
        return "";
    }

    // REPLACE ALL INSTANCES OF find WITH replace
    if (inString.indexOf(find) != -1) {
        // SEPARATE THE STRING INTO AN ARRAY OF STRINGS USING THE VALUE IN find
        t = inString.split(find);

        // JOIN ALL ELEMENTS OF THE ARRAY, SEPARATED BY THE VALUE IN replace
        return (t.join(replace));
    }
    else {
        return inString;
    }
}


// JAVASCRIPT FUNCTION -- DOES NOTHING (USED FOR THE HREF IN THE CALENDAR CALL)
function doNothing() {
}


// ENSURE THAT VALUE IS TWO DIGITS IN LENGTH
function makeTwoDigit(inValue) {

    var numVal = parseInt(inValue, 10);

    // VALUE IS LESS THAN TWO DIGITS IN LENGTH
    if (numVal < 10) {

        // ADD A LEADING ZERO TO THE VALUE AND RETURN IT
        return("0" + numVal);
    }
    else {
        return numVal;
    }
}


// SET FIELD VALUE TO THE DATE SELECTED AND CLOSE THE CALENDAR WINDOW
function returnDate(elm, inDay)
{
    // set hidden field
    calForm = document.getElementsByName('calControl')[0]
    calForm.elements["date0"].value = inDay;
    dayType = "activeDay";

    // inDay = THE DAY THE USER CLICKED ON
    calDate.setDate(inDay);

    // SET THE DATE RETURNED TO THE USER
    var day           = calDate.getDate();
    var month         = calDate.getMonth()+1;
    var year          = calDate.getFullYear();
    var monthString   = getMonthsList()[calDate.getMonth()];
    var monthAbbrev   = monthString.substring(0,3);
    var weekday       = weekdayList[calDate.getDay()];
    var weekdayAbbrev = weekday.substring(0,3);

    outDate = calDateFormat;

    // RETURN TWO DIGIT DAY
    if (calDateFormat.indexOf("DD") != -1) {
        day = makeTwoDigit(day);
        outDate = jsReplace(outDate, "DD", day);
    }
    // RETURN ONE OR TWO DIGIT DAY
    else if (calDateFormat.indexOf("dd") != -1) {
        outDate = jsReplace(outDate, "dd", day);
    }

    // RETURN TWO DIGIT MONTH
    if (calDateFormat.indexOf("MM") != -1) {
        month = makeTwoDigit(month);
        outDate = jsReplace(outDate, "MM", month);
    }
    // RETURN ONE OR TWO DIGIT MONTH
    else if (calDateFormat.indexOf("mm") != -1) {
        outDate = jsReplace(outDate, "mm", month);
    }

    // RETURN FOUR-DIGIT YEAR
    if (calDateFormat.indexOf("yyyy") != -1) {
        outDate = jsReplace(outDate, "yyyy", year);
    }
    // RETURN TWO-DIGIT YEAR
    else if (calDateFormat.indexOf("yy") != -1) {
        var yearString = "" + year;
        var yearString = yearString.substring(2,4);
        outDate = jsReplace(outDate, "yy", yearString);
    }
    // RETURN FOUR-DIGIT YEAR
    else if (calDateFormat.indexOf("YY") != -1) {
        outDate = jsReplace(outDate, "YY", year);
    }

    // RETURN DAY OF MONTH (Initial Caps)
    if (calDateFormat.indexOf("Month") != -1) {
        outDate = jsReplace(outDate, "Month", monthString);
    }
    // RETURN DAY OF MONTH (lowercase letters)
    else if (calDateFormat.indexOf("month") != -1) {
        outDate = jsReplace(outDate, "month", monthString.toLowerCase());
    }
    // RETURN DAY OF MONTH (UPPERCASE LETTERS)
    else if (calDateFormat.indexOf("MONTH") != -1) {
        outDate = jsReplace(outDate, "MONTH", monthString.toUpperCase());
    }

    // RETURN DAY OF MONTH 3-DAY ABBREVIATION (Initial Caps)
    if (calDateFormat.indexOf("Mon") != -1) {
        outDate = jsReplace(outDate, "Mon", monthAbbrev);
    }
    // RETURN DAY OF MONTH 3-DAY ABBREVIATION (lowercase letters)
    else if (calDateFormat.indexOf("mon") != -1) {
        outDate = jsReplace(outDate, "mon", monthAbbrev.toLowerCase());
    }
    // RETURN DAY OF MONTH 3-DAY ABBREVIATION (UPPERCASE LETTERS)
    else if (calDateFormat.indexOf("MON") != -1) {
        outDate = jsReplace(outDate, "MON", monthAbbrev.toUpperCase());
    }

    // RETURN WEEKDAY (Initial Caps)
    if (calDateFormat.indexOf("Weekday") != -1) {
        outDate = jsReplace(outDate, "Weekday", weekday);
    }
    // RETURN WEEKDAY (lowercase letters)
    else if (calDateFormat.indexOf("weekday") != -1) {
        outDate = jsReplace(outDate, "weekday", weekday.toLowerCase());
    }
    // RETURN WEEKDAY (UPPERCASE LETTERS)
    else if (calDateFormat.indexOf("WEEKDAY") != -1) {
        outDate = jsReplace(outDate, "WEEKDAY", weekday.toUpperCase());
    }

    // RETURN WEEKDAY 3-DAY ABBREVIATION (Initial Caps)
    if (calDateFormat.indexOf("Wkdy") != -1) {
        outDate = jsReplace(outDate, "Wkdy", weekdayAbbrev);
    }
    // RETURN WEEKDAY 3-DAY ABBREVIATION (lowercase letters)
    else if (calDateFormat.indexOf("wkdy") != -1) {
        outDate = jsReplace(outDate, "wkdy", weekdayAbbrev.toLowerCase());
    }
    // RETURN WEEKDAY 3-DAY ABBREVIATION (UPPERCASE LETTERS)
    else if (calDateFormat.indexOf("WKDY") != -1) {
        outDate = jsReplace(outDate, "WKDY", weekdayAbbrev.toUpperCase());
    }

    // SET THE VALUE OF THE FIELD THAT WAS PASSED TO THE CALENDAR
//    calDateField.value = outDate;

    // GIVE FOCUS BACK TO THE DATE FIELD
//    calDateField.focus();

//SET EINDDATUM

   calForm.elements["date1"].value = calForm.elements["date0"].value;
   calForm.elements["month1"].value = calForm.elements["month0"].value; 
   calForm.elements["year1"].value = calForm.elements["year0"].value;           

    //submit form with selected date
//    calDateField.form.submit();
    calForm.submit();
}