function positionInfo(object) {
  var p_elm = object;
  this.getElementLeft = getElementLeft;
  function getElementLeft() {
    var x = 0;
    var elm;
    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    while (elm != null) {
      x+= elm.offsetLeft;
      elm = elm.offsetParent;
    }
    return parseInt(x);
  }

  this.getElementWidth = getElementWidth;
  function getElementWidth(){
    var elm;
    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    return parseInt(elm.offsetWidth);
  }



  this.getElementRight = getElementRight;

  function getElementRight(){

    return getElementLeft(p_elm) + getElementWidth(p_elm);

  }



  this.getElementTop = getElementTop;
  function getElementTop() {
    var y = 0;
    var elm;
    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    while (elm != null) {
      y+= elm.offsetTop;
      elm = elm.offsetParent;
    }
    return parseInt(y);
  }

  this.getElementHeight = getElementHeight;
  function getElementHeight(){
    var elm;
    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    return parseInt(elm.offsetHeight);
  }



  this.getElementBottom = getElementBottom;
  function getElementBottom(){
    return getElementTop(p_elm) + getElementHeight(p_elm);
  }

}



function fechamayor(fec0, fec1, iguales){ 
    var sDia0 = fec0.substr(0, 2); 
    var sMes0 = fec0.substr(3, 2); 
    var sAno0 = fec0.substr(6, 4); 
    var sDia1 = fec1.substr(0, 2); 
    var sMes1 = fec1.substr(3, 2); 
    var sAno1 = fec1.substr(6, 4);
    if (sAno0 > sAno1) return true; 
    if (sAno0 < sAno1) return false; 
    if (sMes0 > sMes1) return true; 
    if (sMes0 < sMes1) return false; 
    if (sDia0 > sDia1) return true; 
    if (sDia0 < sDia1) return false; 
    return iguales;
}

function CalendarControl() {
  var calendarId = 'CalendarControl';
  var currentYear = 0;
  var currentMonth = 0;
  var currentDay = 0;
  var selectedYear = 0;
  var selectedMonth = 0;
  var selectedDay = 0;
  var months = ['Enero','Febrero','Marzo','Abril','Mayo','Junio','Julio','Agosto','Septiembre','Octubre','Noviembre','Diciembre'];
  var dateField = null;

  function getProperty(p_property){
    var p_elm = calendarId;
    var elm = null;
    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    if (elm != null){
      if(elm.style){
        elm = elm.style;
        if(elm[p_property]){
          return elm[p_property];
        } else {
          return null;
        }
      } else {
        return null;
      }
    }
  }

  function setElementProperty(p_property, p_value, p_elmId){
    var p_elm = p_elmId;
    var elm = null;
    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    if((elm != null) && (elm.style != null)){
      elm = elm.style;
      elm[ p_property ] = p_value;
    }
  }

  function setProperty(p_property, p_value) {
    setElementProperty(p_property, p_value, calendarId);
  }

  function getDaysInMonth(year, month) {
    return [31,((!(year % 4 ) && ( (year % 100 ) || !( year % 400 ) ))?29:28),31,30,31,30,31,31,30,31,30,31][month-1];
  }

  function getDayOfWeek(year, month, day) {
    var date = new Date(year,month-1,day)
    return date.getDay();
  }

  this.clearDate = clearDate;
  function clearDate() {
    dateField.value = '';
    hide();
  }

  this.setDate = setDate;

  function setDate(year, month, day) {
    if (dateField) {
      if (month < 10) {month = "0" + month;}
      if (day < 10) {day = "0" + day;}

      var dateString = day + "/" + month + "/" + year;
      dateField.value = dateString;
      hide();
    }
    return;
  }


  this.changeMonth = changeMonth;
  function changeMonth(change) {
    currentMonth += change;
    currentDay = 0;
    if(currentMonth > 12) {
      currentMonth = 1;
      currentYear++;
    } else if(currentMonth < 1) {
      currentMonth = 12;
      currentYear--;
    }

    calendar = document.getElementById(calendarId);
    calendar.innerHTML = calendarDrawTable();
  }

  this.changeYear = changeYear;
  function changeYear(change) {
    currentYear += change;
    currentDay = 0;
    calendar = document.getElementById(calendarId);
    calendar.innerHTML = calendarDrawTable();
  }

  function getCurrentYear() {
    var year = new Date().getFullYear();
    return year;
  }

  function getCurrentMonth() {
    return new Date().getMonth() + 1;
  } 

  function getCurrentDay() {
    return new Date().getDate();
  }

  function format(dia, mes, ano){	
	var sDia = ""+dia;
	var sMes = ""+mes;
	var sAno = ""+ano;
	if (sDia.length==1) sDia = "0" + sDia;
	if (sMes.length==1) sMes = "0" + sMes;
	return sDia + "/" + sMes + "/" + sAno;
  }



   function getHoy(){
		var now = new Date();
		return format(now.getDate(), now.getMonth()+1, now.getFullYear());
   }



  function calendarDrawTable() {



    var dayOfMonth = 1;

    var validDay = 0;

    var startDayOfWeek = getDayOfWeek(currentYear, currentMonth, dayOfMonth);

    var daysInMonth = getDaysInMonth(currentYear, currentMonth);

    var css_class = null; //CSS class for each day



    var table = "<table cellspacing='0' cellpadding='0' border='0'>";
    table = table + "<tr class='header'>";
    table = table + "  <td colspan='2' class='previous'><a href='javascript:changeCalendarControlMonth(-1);'>&lt;</a> <a href='javascript:changeCalendarControlYear(-1);'>&laquo;</a></td>";
    table = table + "  <td colspan='3' class='title'>" + months[currentMonth-1] + "<br>" + currentYear + "</td>";
    table = table + "  <td colspan='2' class='next'><a href='javascript:changeCalendarControlYear(1);'>&raquo;</a> <a href='javascript:changeCalendarControlMonth(1);'>&gt;</a></td>";
    table = table + "</tr>";
    table = table + "<tr><th>L</th><th>M</th><th>X</th><th>J</th><th>V</th><th>S</th><th>D</th></tr>";

    for(var week=0; week < 6; week++) {
      table = table + "<tr>";
      for(var dayOfWeek=1; dayOfWeek < 8; dayOfWeek++) {
        if(week == 0 && startDayOfWeek == (dayOfWeek%7)) {
          validDay = 1;
        } else if (validDay == 1 && dayOfMonth > daysInMonth) {
          validDay = 0;
        }
        if(validDay) {
			if (dayOfMonth == selectedDay && currentYear == selectedYear && currentMonth == selectedMonth) {
				css_class = 'current';
			} else if (dayOfWeek == 6 || dayOfWeek == 7) {
				css_class = 'weekend';
			} else {
				css_class = 'weekday';
			}
			if(fechamayor(format(dayOfMonth, currentMonth, currentYear), getHoy(), true)) {
				table = table + "<td><a class='"+css_class+"' href=\"javascript:setCalendarControlDate("+currentYear+","+currentMonth+","+dayOfMonth+");calcularFechas()\">"+dayOfMonth+"</a></td>";
			}else{
				table = table + "<td><a class='"+css_class+"i' >"+dayOfMonth+"</a></td>";
			}
				dayOfMonth++;
			} else {
				table = table + "<td class='empty'>&nbsp;</td>";
			}
      }
      table = table + "</tr>";
    }

    table = table + "<tr class='header'><th colspan='7' style='padding: 3px;'><a href='javascript:hideCalendarControl();'>Cerrar</a></td></tr>";
    table = table + "</table>";



    return table;

  }

  this.show = show;
  function show(field) {
    can_hide = 0;
    if (dateField == field) {
		return;
    } else {
		dateField = field;
    }

    if(dateField) {
      try {
        var dateString = new String(dateField.value);
        var dateParts = dateString.split("-");

        selectedMonth = parseInt(dateParts[0],10);

        selectedDay = parseInt(dateParts[1],10);

        selectedYear = parseInt(dateParts[2],10);

      } catch(e) {}

    }



    if (!(selectedYear && selectedMonth && selectedDay)) {
      selectedMonth = getCurrentMonth();
      selectedDay = getCurrentDay();
      selectedYear = getCurrentYear();
    }

    currentMonth = selectedMonth;
    currentDay = selectedDay;
    currentYear = selectedYear;



    if(document.getElementById){

      calendar = document.getElementById(calendarId);

      calendar.innerHTML = calendarDrawTable(currentYear, currentMonth);

      setProperty('display', 'block');

      var fieldPos = new positionInfo(dateField);

      var calendarPos = new positionInfo(calendarId);



      var x = fieldPos.getElementLeft();

      var y = fieldPos.getElementBottom();



      setProperty('left', x + "px");

      setProperty('top', y + "px");

 

      if (document.all) {

        setElementProperty('display', 'block', 'CalendarControlIFrame');

        setElementProperty('left', x + "px", 'CalendarControlIFrame');

        setElementProperty('top', y + "px", 'CalendarControlIFrame');

        setElementProperty('width', calendarPos.getElementWidth() + "px", 'CalendarControlIFrame');

        setElementProperty('height', calendarPos.getElementHeight() + "px", 'CalendarControlIFrame');

      }

    }

  }



  this.hide = hide;

  function hide() {

    if(dateField) {

      setProperty('display', 'none');

      setElementProperty('display', 'none', 'CalendarControlIFrame');

      dateField = null;

    }

  }



  this.visible = visible;

  function visible() {

    return dateField

  }



  this.can_hide = can_hide;

  var can_hide = 0;

}



var calendarControl = new CalendarControl();



function showCalendarControl(textField) {
  // textField.onblur = hideCalendarControl;
  calendarControl.show(textField);

}



function clearCalendarControl() {

  calendarControl.clearDate();

}



function hideCalendarControl() {

  if (calendarControl.visible()) {

    calendarControl.hide();

  }

}



function setCalendarControlDate(year, month, day) {

  calendarControl.setDate(year, month, day);

}



function changeCalendarControlYear(change) {

  calendarControl.changeYear(change);

}



function changeCalendarControlMonth(change) {

  calendarControl.changeMonth(change);

}



document.write("<iframe id='CalendarControlIFrame' src='javascript:false;' frameBorder='0' scrolling='no'></iframe>");
document.write("<div id='CalendarControl'></div>");