/*****************************************************************************
Copyright (C) 2006  Nick Baicoianu

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
*****************************************************************************/
//constructor for the main Epoch class
function Epoch(name,mode,targetelement,multiselect,extObj)
{
    
    if (extObj){
        this.extObj = extObj;
    }
    this.state = 0;
    this.name = name;
    this.curDate = new Date();
    this.mode = mode;
    this.selectMultiple = (multiselect == true); //'false' is not true or not set at all
    
    //the various calendar variables
    //this.selectedDate = this.curDate;
    this.selectedDates = new Array();
    this.calendar;
    this.calHeading;
    this.calCells;
    this.rows;
    this.cols;
    this.cells = new Array();
    
    //The controls
    this.monthSelect;
    this.yearSelect;
    
    //standard initializations
    this.calConfig();
    this.setDays();
    this.displayYear = this.displayYearInitial;
    this.displayMonth = this.displayMonthInitial;
    
    this.createCalendar(); //create the calendar DOM element and its children, and their related objects
    
    if(this.mode == 'popup' && targetelement && targetelement.type == 'text') //if the target element has been set to be an input text box
    {
        this.tgt = targetelement;
        this.calendar.style.position = 'absolute';
        this.calendar.style.zIndex = '1000000';
        this.topOffset = this.tgt.offsetHeight; // the vertical distance (in pixels) to display the calendar from the Top of its input element
        this.leftOffset = 0;                    // the horizontal distance (in pixels) to display the calendar from the Left of its input element
        this.calendar.style.top = this.getTop(targetelement) + this.topOffset + 'px';
        this.calendar.style.left = this.getLeft(targetelement) + this.leftOffset + 'px';
        document.body.appendChild(this.calendar);
        this.tgt.calendar = this;
        this.tgt.onfocus = function () {this.calendar.show();}; //the calendar will popup when the input element is focused
        //this.tgt.onblur = function () {this.calendar.hide();}; //the calendar will popup when the input element is focused
    }
    else
    {
        this.container = targetelement;
        this.container.appendChild(this.calendar);
    }
    
    this.state = 2; //0: initializing, 1: redrawing, 2: finished!
    this.visible ? this.show() : this.hide();
}
//-----------------------------------------------------------------------------
Epoch.prototype.calConfig = function () //PRIVATE: initialize calendar variables
{
    //this.mode = 'flat'; //can be 'flat' or 'popup'
    this.displayYearInitial = this.curDate.getFullYear(); //the initial year to display on load
    this.displayMonthInitial = this.curDate.getMonth(); //the initial month to display on load (0-11)
    this.rangeYearLower = 2005;
    this.rangeYearUpper = 2018;
    this.minDate = new Date(2005,0,1);
    this.maxDate = new Date(2018,0,1);
    this.startDay = 0; // the day the week will 'start' on: 0(Sun) to 6(Sat)
    this.showWeeks = false; //whether the week numbers will be shown
    this.selCurMonthOnly = false; //allow user to only select dates in the currently displayed month
    this.clearSelectedOnChange = true; //whether to clear all selected dates when changing months
    
    //flat mode-only settings:
    //this.selectMultiple = true; //whether the user can select multiple dates (flat mode only)

    switch(this.mode) //set the variables based on the calendar mode
    {
        case 'popup': //popup options
            this.visible = false;
            break;
        case 'flat':
            this.visible = true;
            
            break;
    }

};
//-----------------------------------------------------------------------------
Epoch.prototype.getTop = function (element) //PRIVATE: returns the absolute Top value of element, in pixels
{
    var oNode = element;
    var iTop = 0;
    while(oNode.tagName != 'BODY') {
        iTop += oNode.offsetTop;
        oNode = oNode.parentNode || oNode.offsetParent;
    }
    
    return iTop;
};
//-----------------------------------------------------------------------------
Epoch.prototype.getLeft = function (element) //PRIVATE: returns the absolute Left value of element, in pixels
{
    var oNode = element;
    var iLeft = 0;
    
    while(oNode.tagName != 'BODY') {
        iLeft += oNode.offsetLeft;
        oNode = oNode.parentNode || oNode.offsetParent;
    }
    
    return iLeft;
};
//-----------------------------------------------------------------------------
Epoch.prototype.show = function () //PUBLIC: displays the calendar
{
    var pos = getElPos(this.tgt);
    pos.top += this.tgt.offsetHeight + 1;
    this.calendar.style.top = pos.top + 'px';
    this.calendar.style.left = pos.left + 'px';

    this.calendar.style.display = 'block';
    this.visible = true;
};
//-----------------------------------------------------------------------------
Epoch.prototype.hide = function () //PUBLIC: Hides the calendar
{
    this.calendar.style.display = 'none';
    this.visible = false;
};
//-----------------------------------------------------------------------------
Epoch.prototype.toggle = function () //PUBLIC: Toggles (shows/hides) the calendar depending on its current state
{
    if(this.visible) {
        this.hide();
    }
    else {
        this.show();
    }
};
//-----------------------------------------------------------------------------
Epoch.prototype.setDays = function ()  //PRIVATE: initializes the standard Gregorian Calendar parameters
{
    var daylist = new Array('Su','Mo','Tu','We','Th','Fr','Sa','Su','Mo','Tu','We','Th','Fr','Sa');
    this.daynames = new Array();
    var j=0;
    for(var i=this.startDay; i< this.startDay + 7;i++) {
        this.daynames[j++] = daylist[i];
    }
        
    this.monthDayCount = new Array(31,((this.curDate.getFullYear() - 2000) % 4 ? 28 : 29),31,30,31,30,31,31,30,31,30,31);
};
//-----------------------------------------------------------------------------
Epoch.prototype.setClass = function (element,className) //PRIVATE: sets the CSS class of the element, W3C & IE
{
    element.setAttribute('class',className);
    element.setAttribute('className',className); //<iehack>
};
//-----------------------------------------------------------------------------
Epoch.prototype.createCalendar = function ()  //PRIVATE: creates the full DOM implementation of the calendar
{
    var tbody, tr, td;
    this.calendar = document.createElement('table');
    this.calendar.setAttribute('id',this.name+'_calendar');
    this.setClass(this.calendar,'calendar');
    //to prevent IE from selecting text when clicking on the calendar
    this.calendar.onselectstart = function() {return false;};
    this.calendar.ondrag = function() {return false;};
    tbody = document.createElement('tbody');
    
    //create the Main Calendar Heading
    tr = document.createElement('tr');
    td = document.createElement('td');
    td.appendChild(this.createMainHeading());
    tr.appendChild(td);
    tbody.appendChild(tr);
    
    //create the calendar Day Heading
    tr = document.createElement('tr');
    td = document.createElement('td');
    td.appendChild(this.createDayHeading());
    tr.appendChild(td);
    tbody.appendChild(tr);

    //create the calendar Day Cells
    tr = document.createElement('tr');
    td = document.createElement('td');
    td.setAttribute('id',this.name+'_cell_td');
    this.calCellContainer = td; //used as a handle for manipulating the calendar cells as a whole
    td.appendChild(this.createCalCells());
    tr.appendChild(td);
    tbody.appendChild(tr);
    
    //create the calendar footer
    tr = document.createElement('tr');
    td = document.createElement('td');
    td.appendChild(this.createFooter());
    tr.appendChild(td);
    tbody.appendChild(tr);
    
    //add the tbody element to the main calendar table
    this.calendar.appendChild(tbody);
};
//-----------------------------------------------------------------------------
Epoch.prototype.createMainHeading = function () //PRIVATE: Creates the primary calendar heading, with months & years
{
    var months = new Array('Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec');
    //create the containing <div> element
    var container = document.createElement('div');
    container.setAttribute('id',this.name+'_mainheading');
    this.setClass(container,'mainheading');
    //create the child elements and other variables
    this.monthSelect = document.createElement('select');
    this.yearSelect = document.createElement('select');
    var monthDn = document.createElement('input'), monthUp = document.createElement('input');
    var opt, i;
    //fill the month select box
    for(i=0;i<12;i++)
    {
        opt = document.createElement('option');
        opt.setAttribute('value',i);
        if(this.state == 0 && this.displayMonth == i) {
            opt.setAttribute('selected','selected');
        }
        opt.appendChild(document.createTextNode(months[i]));
        this.monthSelect.appendChild(opt);
    }
    //and fill the year select box
    for(i=this.rangeYearLower;i<=this.rangeYearUpper;i++)
    {
        opt = document.createElement('option');
        opt.setAttribute('value',i);
        if(this.state == 0 && this.displayYear == i) {
            opt.setAttribute('selected','selected');
        }
        opt.appendChild(document.createTextNode(i));
        this.yearSelect.appendChild(opt);       
    }
    //add the appropriate children for the month buttons
    monthUp.setAttribute('type','button');
    monthUp.setAttribute('value','>');
    monthUp.setAttribute('title','Go to the next month');
    monthDn.setAttribute('type','button');
    monthDn.setAttribute('value','<');
    monthDn.setAttribute('title','Go to the previous month');
    this.monthSelect.owner = this.yearSelect.owner = monthUp.owner = monthDn.owner = this;  //hack to allow us to access this calendar in the events (<fix>??)
    
    //assign the event handlers for the controls
    monthUp.onmouseup = function () {this.owner.nextMonth();};
    monthDn.onmouseup = function () {this.owner.prevMonth();};
    this.monthSelect.onchange = function() {
        this.owner.displayMonth = this.value;
        this.owner.displayYear = this.owner.yearSelect.value; 
        this.owner.goToMonth(this.owner.displayYear,this.owner.displayMonth);
    };
    this.yearSelect.onchange = function() {
        this.owner.displayMonth = this.owner.monthSelect.value;
        this.owner.displayYear = this.value; 
        this.owner.goToMonth(this.owner.displayYear,this.owner.displayMonth);
    };
    
    //and finally add the elements to the containing div
    container.appendChild(monthDn);
    container.appendChild(this.monthSelect);
    container.appendChild(this.yearSelect);
    container.appendChild(monthUp);
    return container;
};
//-----------------------------------------------------------------------------
Epoch.prototype.createFooter = function () //PRIVATE: creates the footer of the calendar - goes under the calendar cells
{
    var container = document.createElement('div');

    var clearSelected = document.createElement('input');
    clearSelected.setAttribute('type','button');
    clearSelected.setAttribute('value','Clear');
    clearSelected.setAttribute('title','Clears any dates selected on the calendar');
    clearSelected.owner = this;
    clearSelected.onclick = function() { this.owner.resetSelections(false);};
    container.appendChild(clearSelected);

    var cancelCalendar = document.createElement('input');
    cancelCalendar.setAttribute('type','button');
    cancelCalendar.setAttribute('value','Cancel');
    cancelCalendar.setAttribute('title','Close the calendar');
    cancelCalendar.owner = this;
    cancelCalendar.onclick = function() { this.owner.hide();};
    container.appendChild(cancelCalendar);
    return container;
};
//-----------------------------------------------------------------------------
Epoch.prototype.resetSelections = function (returnToDefaultMonth)  //PRIVATE: reset the calendar's selection variables to defaults
{
    this.selectedDates = new Array();
    this.rows = new Array(false,false,false,false,false,false,false);
    this.cols = new Array(false,false,false,false,false,false,false);
    if(this.tgt)  //if there is a target element, clear it too
    {
        this.tgt.value = null;
        this.tgt.jsdate = 0;
        if(this.mode == 'popup') {//hide the calendar if in popup mode
            this.hide();
        }
    }
        
    if(returnToDefaultMonth == true) {
        this.goToMonth(this.displayYearInitial,this.displayMonthInitial);
    }
    else {
        this.reDraw();
    }
};
//-----------------------------------------------------------------------------
Epoch.prototype.createDayHeading = function ()  //PRIVATE: creates the heading containing the day names
{
    //create the table element
    this.calHeading = document.createElement('table');
    this.calHeading.setAttribute('id',this.name+'_caldayheading');
    this.setClass(this.calHeading,'caldayheading');
    var tbody,tr,td;
    tbody = document.createElement('tbody');
    tr = document.createElement('tr');
    this.cols = new Array(false,false,false,false,false,false,false);
    
    //if we're showing the week headings, create an empty <td> for filler
    if(this.showWeeks)
    {
        td = document.createElement('td');
        td.setAttribute('class','wkhead');
        td.setAttribute('className','wkhead'); //<iehack>
        tr.appendChild(td);
    }
    //populate the day titles
    for(var dow=0;dow<7;dow++)
    {
        td = document.createElement('td');
        td.appendChild(document.createTextNode(this.daynames[dow]));
        if(this.selectMultiple) { //if selectMultiple is true, assign the cell a CalHeading Object to handle all events
            td.headObj = new CalHeading(this,td,(dow + this.startDay < 7 ? dow + this.startDay : dow + this.startDay - 7));
        }
        tr.appendChild(td);
    }
    tbody.appendChild(tr);
    this.calHeading.appendChild(tbody);
    return this.calHeading; 
};
//-----------------------------------------------------------------------------
Epoch.prototype.createCalCells = function ()  //PRIVATE: creates the table containing the calendar day cells
{
    this.rows = new Array(false,false,false,false,false,false);
    this.cells = new Array();
    var row = -1, totalCells = (this.showWeeks ? 48 : 42);
    var beginDate = new Date(this.displayYear,this.displayMonth,1);
    var endDate = new Date(this.displayYear,this.displayMonth,this.monthDayCount[this.displayMonth]);
    var sdt = new Date(beginDate);
    sdt.setDate(sdt.getDate() + (this.startDay - beginDate.getDay()) - (this.startDay - beginDate.getDay() > 0 ? 7 : 0) );
    //create the table element
    this.calCells = document.createElement('table');
    this.calCells.setAttribute('id',this.name+'_calcells');
    this.setClass(this.calCells,'calcells');
    var tbody,tr,td;
    tbody = document.createElement('tbody');
    for(var i=0;i<totalCells;i++)
    {
        if(this.showWeeks) //if we are showing the week headings
        {
            if(i % 8 == 0)
            {
                row++;
                tr = document.createElement('tr');
                td = document.createElement('td');
                if(this.selectMultiple) { //if selectMultiple is enabled, create the associated weekObj objects
                    td.weekObj = new WeekHeading(this,td,sdt.getWeek(),row)
                }
                else //otherwise just set the class of the td for consistent look
                {
                    td.setAttribute('class','wkhead');
                    td.setAttribute('className','wkhead'); //<iehack>
                }
                td.appendChild(document.createTextNode(sdt.getWeek()));         
                tr.appendChild(td);
                i++;
            }
        }
        else if(i % 7 == 0) //otherwise, new row every 7 cells
        {
            row++;
            tr = document.createElement('tr');
        }
        //create the day cells
        td = document.createElement('td');
        td.appendChild(document.createTextNode(sdt.getDate()));// +' ' +sdt.getUeDay()));
        var cell = new CalCell(this,td,sdt,row);
        this.cells.push(cell);
        td.cellObj = cell;
        sdt.setDate(sdt.getDate() + 1); //increment the date
        tr.appendChild(td);
        tbody.appendChild(tr);
    }
    this.calCells.appendChild(tbody);
    this.reDraw();
    return this.calCells;
};
//-----------------------------------------------------------------------------
Epoch.prototype.reDraw = function () //PRIVATE: reapplies all the CSS classes for the calendar cells, usually called after chaning their state
{
    this.state = 1;
    var i,j;
    for(i=0;i<this.cells.length;i++) {
        this.cells[i].selected = false;
    }
    for(i=0;i<this.cells.length;i++)
    {
        for(j=0;j<this.selectedDates.length;j++) { //if the cell's date is in the selectedDates array, set its selected property to true
            if(this.cells[i].date.getUeDay() == this.selectedDates[j].getUeDay() ) {
                this.cells[i].selected = true;
            }
        }

        this.cells[i].setClass();
    }
    //alert(this.selectedDates);
    this.state = 2;
};
//-----------------------------------------------------------------------------
Epoch.prototype.deleteCells = function () //PRIVATE: removes the calendar cells from the DOM (does not delete the cell objects associated with them
{
    this.calCellContainer.removeChild(this.calCellContainer.firstChild); //get a handle on the cell table (optional - for less indirection)
    this.cells = new Array(); //reset the cells array
};
//-----------------------------------------------------------------------------
Epoch.prototype.goToMonth = function (year,month) //PUBLIC: sets the calendar to display the requested month/year
{
    this.monthSelect.value = this.displayMonth = month;
    this.yearSelect.value = this.displayYear = year;
    this.deleteCells();
    this.calCellContainer.appendChild(this.createCalCells());
};
//-----------------------------------------------------------------------------
Epoch.prototype.nextMonth = function () //PUBLIC: go to the next month.  if the month is december, go to january of the next year
{
    
    //increment the month/year values, provided they're within the min/max ranges
    if(this.monthSelect.value < 11) {
        this.monthSelect.value++;
    }
    else
    {
        if(this.yearSelect.value < this.rangeYearUpper)
        {
            this.monthSelect.value = 0;
            this.yearSelect.value++;
        }
        else {
            alert('This is the maximum range');
        }
    }
    //assign the currently displaying month/year values
    this.displayMonth = this.monthSelect.value;
    this.displayYear = this.yearSelect.value;
    
    //and refresh the calendar for the new month/year
    this.deleteCells();
    this.calCellContainer.appendChild(this.createCalCells());
};
//-----------------------------------------------------------------------------
Epoch.prototype.prevMonth = function () //PUBLIC: go to the previous month.  if the month is january, go to december of the previous year
{
    //increment the month/year values, provided they're within the min/max ranges
    if(this.monthSelect.value > 0)
        this.monthSelect.value--;
    else
    {
        if(this.yearSelect.value > this.rangeYearLower)
        {
            this.monthSelect.value = 11;
            this.yearSelect.value--;
        }
        else {
            alert('This is the maximum range');
        }
    }
    
    //assign the currently displaying month/year values
    this.displayMonth = this.monthSelect.value;
    this.displayYear = this.yearSelect.value;
    
    //and refresh the calendar for the new month/year
    this.deleteCells();
    this.calCellContainer.appendChild(this.createCalCells());
};
//-----------------------------------------------------------------------------
Epoch.prototype.addZero = function (vNumber) //PRIVATE: pads a 2 digit number with a leading zero
{
    return ((vNumber < 10) ? '0' : '') + vNumber;
};
//-----------------------------------------------------------------------------
Epoch.prototype.addDates = function (dates,redraw)  //PUBLIC: adds the array "dates" to the calendars selectedDates array (no duplicate dates) and redraws the calendar
{
    var j,in_sd;
    for(var i=0;i<dates.length;i++)
    {   
        in_sd = false;
        for(j=0;j<this.selectedDates.length;j++)
        {
            if(dates[i].getUeDay() == this.selectedDates[j].getUeDay())
            {
                in_sd = true;
                break;
            }
        }
        if(!in_sd) { //if the date isn't already in the array, add it!
            this.selectedDates.push(dates[i]);
        }
    }
    if(redraw != false) {//redraw  the calendar if "redraw" is false or undefined
        this.reDraw();
    }
};
//-----------------------------------------------------------------------------
Epoch.prototype.removeDates = function (dates,redraw)  //PUBLIC: adds the dates to the calendars selectedDates array and redraws the calendar
{
    var j;
    for(var i=0;i<dates.length;i++)
    {
        for(j=0;j<this.selectedDates.length;j++)
        {
            if(dates[i].getUeDay() == this.selectedDates[j].getUeDay()) { //search for the dates in the selectedDates array, removing them if the dates match
                this.selectedDates.splice(j,1);
            }
        }
    }
    if(redraw != false) { //redraw  the calendar if "redraw" is false or undefined
        this.reDraw();
    }
};
//-----------------------------------------------------------------------------
Epoch.prototype.outputDate = function (vDate, vFormat) //PUBLIC: outputs a date in the appropriate format (DEPRECATED)
{
    var vDay            = this.addZero(vDate.getDate()); 
    var vMonth          = this.addZero(vDate.getMonth() + 1); 
    var vYearLong       = this.addZero(vDate.getFullYear()); 
    var vYearShort      = this.addZero(vDate.getFullYear().toString().substring(3,4)); 
    var vYear           = (vFormat.indexOf('yyyy') > -1 ? vYearLong : vYearShort);
    var vHour           = this.addZero(vDate.getHours()); 
    var vMinute         = this.addZero(vDate.getMinutes()); 
    var vSecond         = this.addZero(vDate.getSeconds()); 
    return vFormat.replace(/dd/g, vDay).replace(/mm/g, vMonth).replace(/y{1,4}/g, vYear).replace(/hh/g, vHour).replace(/nn/g, vMinute).replace(/ss/g, vSecond);
};
//-----------------------------------------------------------------------------

/*****************************************************************************/
function CalHeading(owner,tableCell,dow)
{
    this.owner = owner;
    this.tableCell = tableCell;
    this.dayOfWeek = dow;
    
    //the event handlers
    this.tableCell.onclick = this.onclick;
}
//-----------------------------------------------------------------------------
CalHeading.prototype.onclick = function ()
{
    //reduce indirection:
    var owner = this.headObj.owner;
    var sdates = owner.selectedDates;
    var cells = owner.cells;
    
    owner.cols[this.headObj.dayOfWeek] = !owner.cols[this.headObj.dayOfWeek];
    for(var i=0;i<cells.length;i++) //cycle through all the cells in the calendar, selecting all cells with the same dayOfWeek as this heading
    {
        if(cells[i].dayOfWeek == this.headObj.dayOfWeek && (!owner.selCurMonthOnly || cells[i].date.getMonth() == owner.displayMonth && cells[i].date.getFullYear() == owner.displayYear)) //if the cell's DoW matches, with other conditions
        {
            if(owner.cols[this.headObj.dayOfWeek])      //if selecting, add the cell's date to the selectedDates array
            {
                if(owner.selectedDates.arrayIndex(cells[i].date) == -1) { //if the date isn't already in the array
                    sdates.push(cells[i].date);
                }
            }
            else                                        //otherwise, remove it
            {
                for(var j=0;j<sdates.length;j++) 
                {
                    if(cells[i].dayOfWeek == sdates[j].getDay())
                    {
                        sdates.splice(j,1); //remove dates that are within the displaying month/year that have the same day of week as the day cell
                        break;
                    }
                }
            }
            cells[i].selected = owner.cols[this.headObj.dayOfWeek];
        }
    }
    owner.reDraw();
};
/*****************************************************************************/
function WeekHeading(owner,tableCell,week,row)
{
    this.owner = owner;
    this.tableCell = tableCell;
    this.week = week;
    this.tableRow = row;
    this.tableCell.setAttribute('class','wkhead');
    this.tableCell.setAttribute('className','wkhead'); //<iehack>
    //the event handlers
    this.tableCell.onclick = this.onclick;
}
//-----------------------------------------------------------------------------
WeekHeading.prototype.onclick = function ()
{
    //reduce indirection:
    var owner = this.weekObj.owner;
    var cells = owner.cells;
    var sdates = owner.selectedDates;
    var i,j;
    owner.rows[this.weekObj.tableRow] = !owner.rows[this.weekObj.tableRow];
    for(i=0;i<cells.length;i++)
    {
        if(cells[i].tableRow == this.weekObj.tableRow)
        {
            if(owner.rows[this.weekObj.tableRow] && (!owner.selCurMonthOnly || cells[i].date.getMonth() == owner.displayMonth && cells[i].date.getFullYear() == owner.displayYear)) //match all cells in the current row, with option to restrict to current month only
            {
                if(owner.selectedDates.arrayIndex(cells[i].date) == -1) {//if the date isn't already in the array
                    sdates.push(cells[i].date);
                }
            }
            else                                        //otherwise, remove it
            {
                for(j=0;j<sdates.length;j++)
                {
                    if(sdates[j].getTime() == cells[i].date.getTime())  //this.weekObj.tableRow && sdates[j].getMonth() == owner.displayMonth && sdates[j].getFullYear() == owner.displayYear)
                    {
                        sdates.splice(j,1); //remove dates that are within the displaying month/year that have the same day of week as the day cell
                        break;
                    }
                }
            }
        }
    }
    owner.reDraw();
};
/*****************************************************************************/
//-----------------------------------------------------------------------------
function CalCell(owner,tableCell,dateObj,row)
{
    this.owner = owner;     //used primarily for event handling
    this.tableCell = tableCell;             //the link to this cell object's table cell in the DOM
    this.cellClass;         //the CSS class of the cell
    this.selected = false;  //whether the cell is selected (and is therefore stored in the owner's selectedDates array)
    this.date = new Date(dateObj);
    this.dayOfWeek = this.date.getDay();
    this.week = this.date.getWeek();
    this.tableRow = row;
    
    //assign the event handlers for the table cell element
    this.tableCell.onclick = this.onclick;
    this.tableCell.onmouseover = this.onmouseover;
    this.tableCell.onmouseout = this.onmouseout;
    
    //and set the CSS class of the table cell
    this.setClass();
}
//-----------------------------------------------------------------------------
CalCell.prototype.onmouseover = function () //replicate CSS :hover effect for non-supporting browsers <iehack>
{
    this.setAttribute('class',this.cellClass + ' hover');
    this.setAttribute('className',this.cellClass + ' hover');
};
//-----------------------------------------------------------------------------
CalCell.prototype.onmouseout = function () //replicate CSS :hover effect for non-supporting browsers <iehack>
{
    this.cellObj.setClass();
};
//-----------------------------------------------------------------------------
CalCell.prototype.onclick = function () 
{
    //reduce indirection:
    var cell = this.cellObj;
    var owner = cell.owner;
    if(!owner.selCurMonthOnly || cell.date.getMonth() == owner.displayMonth && cell.date.getFullYear() == owner.displayYear)
    {
        if(owner.selectMultiple == true)  //if we can select multiple cells simultaneously, add the currently selected cell's date to the selectedDates array
        {
            if(!cell.selected) //if this cell has been selected
            {
                if(owner.selectedDates.arrayIndex(cell.date) == -1) {
                    owner.selectedDates.push(cell.date);
                }
            }
            else        
            {
                var tmp = owner.selectedDates; // to reduce indirection
                //if the cell has been deselected, remove it from the owner calendar's selectedDates array
                for(var i=0;i<tmp.length;i++)
                {
                    if(tmp[i].getUeDay() == cell.date.getUeDay()) {
                        tmp.splice(i,1);
                    }
                }
            }
        }
        else //if we can only select one cell at a time
        {
            owner.selectedDates = new Array(cell.date);
            if(owner.tgt) //if there is a target element to place the value in, do so
            {
                owner.tgt.jsdate = owner.selectedDates[0].getTime();
                owner.tgt.value = owner.outputDate(owner.selectedDates[0],'dd/mm/yyyy');
                if (owner.extObj){
                    owner.extObj.onCalSelected(owner.selectedDates[0]);
                }
                if(owner.mode == 'popup') {
                    owner.hide();
                }
            }
        }
        owner.reDraw(); //redraw the calendar cell styles to reflect the changes
    }
};
//-----------------------------------------------------------------------------
CalCell.prototype.setClass = function ()  //private: sets the CSS class of the cell based on the specified criteria
{
    if(this.selected) {
        this.cellClass = 'cell_selected';
    }
    else if(this.owner.displayMonth != this.date.getMonth() ) {
        this.cellClass = 'notmnth'; 
    }
    else if(this.date.getDay() > 0 && this.date.getDay() < 6) {
        this.cellClass = 'wkday';
    }
    else {
        this.cellClass = 'wkend';
    }
    
    if(this.date.getFullYear() == this.owner.curDate.getFullYear() && this.date.getMonth() == this.owner.curDate.getMonth() && this.date.getDate() == this.owner.curDate.getDate()) {
        this.cellClass = this.cellClass + ' curdate';
    }

    this.tableCell.setAttribute('class',this.cellClass);
    this.tableCell.setAttribute('className',this.cellClass); //<iehack>
};
/*****************************************************************************/
Date.prototype.getDayOfYear = function () //returns the day of the year for this date
{
    return parseInt((this.getTime() - new Date(this.getFullYear(),0,1).getTime())/86400000 + 1);
};
//-----------------------------------------------------------------------------
Date.prototype.getWeek = function () //returns the day of the year for this date
{
    return parseInt((this.getTime() - new Date(this.getFullYear(),0,1).getTime())/604800000 + 1);
};
//-----------------------------------------------------------------------------
Date.prototype.getUeDay = function () //returns the number of DAYS since the UNIX Epoch - good for comparing the date portion
{
    return parseInt(Math.floor((this.getTime() - this.getTimezoneOffset() * 60000)/86400000)); //must take into account the local timezone
};
//-----------------------------------------------------------------------------
Date.prototype.dateFormat = function(format)
{
    if(!format) { //if no format is specified, assign a default (in this case the ISO 8601 date/time format.  this default can be safely changed)
        format = 'Y-m-d H:i:s';
    }
    LZ = function(x) {return(x < 0 || x > 9 ? '' : '0') + x};
    var MONTH_NAMES = new Array('January','February','March','April','May','June','July','August','September','October','November','December','Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec');
    var DAY_NAMES = new Array('Sunday','Monday','Tuesday','Wednesday','Thursday','Friday','Saturday','Sun','Mon','Tue','Wed','Thu','Fri','Sat');
    format = format + "";
    var result="";
    var i_format=0;
    var c="";
    var token="";
    var y=this.getFullYear().toString();
    var M=this.getMonth()+1;
    var d=this.getDate();
    var E=this.getDay();
    var H=this.getHours();
    var m=this.getMinutes();
    var s=this.getSeconds();
    var yyyy,yy,MMM,MM,dd,hh,h,mm,ss,ampm,HH,H,KK,K,kk,k;
    // Convert real this parts into formatted versions
    var value = new Object();
    //if (y.length < 4) {y=''+(y-0+1900);}
    value['Y'] = y.toString();
    value['y'] = y.substring(2);
    value['n'] = M;
    value['m'] = LZ(M);
    value['F'] = MONTH_NAMES[M-1];
    value['M'] = MONTH_NAMES[M+11];
    value['j'] = d;
    value['d'] = LZ(d);
    value['D'] = DAY_NAMES[E+7];
    value['l'] = DAY_NAMES[E];
    value['G'] = H;
    value['H'] = LZ(H);
    if (H==0) {value['g']=12;}
    else if (H>12){value['g']=H-12;}
    else {value['g']=H;}
    value['h']=LZ(value['g']);
    if (H > 11) {value['a']='pm'; value['A'] = 'PM';}
    else { value['a']='am'; value['A'] = 'AM';}
    value['i']=LZ(m);
    value['s']=LZ(s);
    //construct the result string
    while (i_format < format.length) {
        c=format.charAt(i_format);
        token="";
        while ((format.charAt(i_format)==c) && (i_format < format.length)) {
            token += format.charAt(i_format++);
            }
        if (value[token] != null) { result=result + value[token]; }
        else { result=result + token; }
        }
    return result;
};
/*****************************************************************************/
/*
Array.prototype.arrayIndex = function(searchVal,startIndex) //similar to array.indexOf() - created to fix IE deficiencies
{
    startIndex = (startIndex != null ? startIndex : 0); //default startIndex to 0, if not set
    for(var i=startIndex;i<this.length;i++)
    {
        if(searchVal == this[i]) {
            return i;
        }
    }
    return -1;
};
*/
/*****************************************************************************/