/**
This is a JavaScript library that will allow you to easily add some basic DHTML
drop-down datepicker functionality to your Notes forms. This script is not as
full-featured as others you may find on the Internet, but it's free, it's easy to
understand, and it's easy to change.

You'll also want to include a stylesheet that makes the datepicker elements
look nice. An example one can be found in the database that this script was
originally released with, at:

http://www.nsftools.com/tips/NotesTips.htm#datepicker

version 1.5
December 4, 2005
Julian Robichaux -- http://www.nsftools.com
*/

var dpLastDateFieldId;

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

var dayArrayShort = new Array('S', 'M', 'T', 'W', 'T', 'F', 'S');
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');
 
// 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 = "mdy"    // valid values are "mdy", "dmy", and "ymd"
var dateSeparator = defaultDateSeparator;
var dateFormat = defaultDateFormat;

/**
This is the main function you'll call from the onClick event of a button.
Normally, you'll have something like this on your HTML page:
*/
function displayDatePicker(dateFieldId, displayBelowThisObject, dtFormat, dtSep)
{
  var targetDateField = document.getElementById(dateFieldId);
  
  // only want the calendar to open the first time the textbox obtains focus.
  document.detachEvent ? targetDateField.detachEvent('onfocus', textboxFocus) : targetDateField.removeEventListener('focus', textboxFocus, false);
 
  // 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 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 = 50000;
 
  // draw the datepicker table
  refreshDatePicker(targetDateField.id, dt.getFullYear(), dt.getMonth(), dt.getDate());
}


/**
This is the function that actually draws the datepicker calendar.
*/
function refreshDatePicker(dateFieldId, 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();
  var selectedDay = new Date(year, month, day);
 
  if ((month >= 0) && (year > 0)) {
    thisDay = new Date(year, month, 1);
  } else {
    day = thisDay.getDate();
    thisDay.setDate(1);
  }
 
  // get the day limits allowed for selection.
  var minDay = window[dateFieldId + "MinDate"];
  var maxDay = window[dateFieldId + "MaxDate"];
  
  // make sure the date is after the minDay.
  if(minDay && minDay > selectedDay) {
    thisDay = new Date(minDay.getFullYear(), minDay.getMonth(), 1);
    day = minDay.getDate();
  }
  
  // make sure the date is before the maxDay.
  if(maxDay && maxDay < selectedDay) {
    thisDay = new Date(maxDay.getFullYear(), maxDay.getMonth(), 1);
    day = maxDay.getDate();
  }
  
  // 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_inactive_day = "<td class='dpTD dpInactiveTD'>";
  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(dateFieldId, thisDay, -1, "previous", minDay, maxDay) + xTD;
  html += TD_title + DIV_title + monthArrayLong[ thisDay.getMonth()] + " " + thisDay.getFullYear() + xDIV + xTD;
  html += TD_buttons + getButtonCode(dateFieldId, thisDay, 1, "next", minDay, maxDay) + 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_inactive_day + "&nbsp;" + xTD;
 
  // now, the days of the month
  var weeks = 1;
  do {
    dayNum = thisDay.getDate();
    TD_onclick = " onclick=\"updateDateField('" + dateFieldId + "', '" + getDateString(thisDay) + "');\">";

    // determine how to show the day.
    if ((minDay && thisDay < minDay) || (maxDay && thisDay > maxDay)) {
      // if the date is outside of the specified range, inactivate it.
      html += TD_inactive_day + dayNum + xTD;
    } else if (dayNum == day) {
      // if the day is the selected day, highlight it.
      html += TD_selected + TD_onclick + DIV_selected + dayNum + xDIV + xTD;
    } else {
      html += TD + TD_onclick + dayNum + xTD;
    }
    
    // if this is a Saturday, end the row.
    if (thisDay.getDay() == 6) {
      html += xTR;

      // if this is the end of the month, don't start a new row.
      if (thisDay.getDate() < daysInMonth(thisDay.getMonth() + 1, thisDay.getFullYear())) {
        html += TR;
        ++weeks;
      }
    }
    
    // increment the day
    thisDay.setDate(thisDay.getDate() + 1);
  } while (thisDay.getDate() > 1)
  
  // fill in any trailing blanks
  if (thisDay.getDay() > 0) {
    for (i = 7; i > thisDay.getDay(); i--)
      html += TD_inactive_day + "&nbsp;" + xTD;
      
    html += xTR;
  }

  // make sure the calendar always displays 7 weeks.
  while(weeks < 6) {
    html += TR;
    for (k = 0;k < 7;++k) {
      html += TD_inactive_day + "&nbsp;" + xTD;
    }
    html += xTR;
    ++weeks;
  }
 
  // 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(\"" + dateFieldId + "\");'>today</button> ";
  html += "<button class='dpTodayButton' onClick='updateDateField(\"" + dateFieldId + "\");'>close</button>";
  html += xTD + xTR;
  
  // Keep track of last opened 
  dpLastDateFieldId = dateFieldId;
  document.attachEvent ? document.attachEvent('onclick', closeLastDatePicker) : document.addEventListener('click', closeLastDatePicker, false);
 
  // 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();
}

/* Closes the last opened date picker. */
function closeLastDatePicker(e)
{
  var elem = getEventSource(e);
  
  if (elem) {
    // If the click was in the date picker, ignore it.
    if(isInDatePicker(elem)) return;
    
    // If the click came from the textbox, ignore it.
    if(elem.id == dpLastDateFieldId) return;
    
    // If the click came from the date anchor, ignore it.
    if(elem.id == dpLastDateFieldId + "Anchor") return;
    
    // If the click came from the date image, ignore it.
    if(elem.id == dpLastDateFieldId + "Image") return;
  }
  
  // Close the date picker.
  skipBookingUpdate = true;
  updateDateField(dpLastDateFieldId);
  document.detachEvent ? document.detachEvent('onclick', closeLastDatePicker) : document.removeEventListener('click', closeLastDatePicker, false);
}

/* Determines if an element is in the date picker. */
function isInDatePicker(elem)
{
  // Looks at up to 10 parent nodes.
  for (i = 0;i < 10;++i) {
    elem = elem.parentNode;
    
    // If the parent node is null, return false.
    if(elem == null) return false;
    
    // If the parent node is the datepicker div, return true.
    if(elem.id == datePickerDivID) return true;
  }
}


/**
Convenience function for writing the code for the buttons that bring us back or forward
a month.
*/
function getButtonCode(dateFieldId, dateVal, adjust, label, minDay, maxDay)
{
  var newMonth = (dateVal.getMonth () + adjust) % 12;
  var newYear = dateVal.getFullYear() + parseInt((dateVal.getMonth() + adjust) / 12);
  if (newMonth < 0) {
    newMonth += 12;
    newYear += -1;
  }
  
  // Don't allow moving to next or previous month if outside of range.
  if((minDay && minDay > new Date(newYear, newMonth, daysInMonth(newMonth, newYear))) || 
     (maxDay && maxDay < new Date(newYear, newMonth, 1)))
    return "&nbsp";
  
  var href = "javascript:refreshDatePicker('" + dateFieldId + "', " + newYear + ", " + newMonth + ");";
  
  if(label == "next") {
    return "<a href=\"" + href + "\" class=\"pagination_next\" style=\"cursor: pointer;\">&nbsp;</a>";
  } else {
    return "<a href=\"" + href + "\" class=\"pagination_prev\" style=\"cursor: pointer;\">&nbsp;</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);
 
  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 && dateString.match("Check") == null) {
      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.match("Check") != null)    //checks for 'check-in' or 'check-out' date watermarks
    dArray = false;
  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 if (dateString.indexOf("\\") >= 0)
    dArray = dateString.split("\\");
  else
    dArray = false;
 
  return dArray;
}

/**
Update the field with the given dateFieldId 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.

Also, if the page developer has defined a function called datePickerClosed anywhere on
the page or in an imported library, we will attempt to run that function with the updated
field as a parameter. This can be used for such things as date validation, setting default
values for related fields, etc. For example, you might have a function like this to validate
a start date field:

function datePickerClosed(dateField)
{
  var dateObj = getFieldDate(dateField.value);
  var today = new Date();
  today = new Date(today.getFullYear(), today.getMonth(), today.getDate());
 
  if (dateField.name == "StartDate") {
    if (dateObj < today) {
      // if the date is before today, alert the user and display the datepicker again
      alert("Please enter a date that is today or later");
      dateField.value = "";
      document.getElementById(datePickerDivID).style.visibility = "visible";
      adjustiFrame();
    } else {
      // if the date is okay, set the EndDate field to 7 days after the StartDate
      dateObj.setTime(dateObj.getTime() + (7 * 24 * 60 * 60 * 1000));
      var endDateField = document.getElementsByName ("EndDate").item(0);
      endDateField.value = getDateString(dateObj);
    }
  }
}

*/
function updateDateField(dateFieldId, dateString)
{
  var targetDateField = document.getElementById (dateFieldId);
  if (dateString) {
    targetDateField.focus();
    targetDateField.value = dateString;
  }
 
  var pickerDiv = document.getElementById(datePickerDivID);
  pickerDiv.style.visibility = "hidden";
  pickerDiv.style.display = "none";
 
  adjustiFrame();
 
  // 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);
    
  if(!skipBookingUpdate)
  {
    if(targetDateField.id == "ctl00_phContent_StartDatePickerTextBox2Booking")
    {
    updateValidation("ctl00_phContent_RangeValidator2");
    setTimeout('__doPostBack(\'ctl00$phContent$StartDatePickerTextBox2Booking\',\'\')', 0);
    }
    else if(targetDateField.id == "ctl00_phContent_EndDatePickerTextBox2Booking")
    {
    updateValidation("ctl00_phContent_RangeValidator1");    
    setTimeout('__doPostBack(\'ctl00$phContent$EndDatePickerTextBox2Booking\',\'\')', 0);
    }
  }
  skipBookingUpdate = false;
}

function updateValidation(validatorToUpdate)
{
    var a = $get(validatorToUpdate);
    a.isvalid = a.evaluationfunction(a);
    ValidatorUpdateDisplay(a);
}

/**
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) {
  }
}

/* fires when the textbox obtains focus the first time. */
function textboxFocus(e)
{
  var elem = getEventSource(e);

  displayDatePicker(elem.id);
}