function isEmailAddr(email)
{
  var result = false;
  var theStr = new String(email);
  var index = theStr.indexOf("@");
  if (index > 0)
  {
    var pindex = theStr.indexOf(".",index);
    if ((pindex > index+1) && (theStr.length > pindex+1))
    result = true;
  }
  return result;
}

function validRequired(formField,fieldLabel)
{
    var result = true;

    if (formField.value == "")
    {
        alert('El campo "' + fieldLabel +'" es requerido.');
        formField.focus();
        result = false;
    }

    return result;
}

function allDigits(str)
{
    return inValidCharSet(str,"0123456789");
}

function inValidCharSet(str,charset)
{
    var result = true;

    // Note: doesn't use regular expressions to avoid early Mac browser bugs
    for (var i=0;i<str.length;i++)
        if (charset.indexOf(str.substr(i,1))<0)
        {
            result = false;
            break;
        }

    return result;
}

function validEmail(formField,fieldLabel,required)
{
    var result = true;

    if (required && !validRequired(formField,fieldLabel))
        result = false;

    if (result && ((formField.value.length < 3) || !isEmailAddr(formField.value)) )
    {
        alert("Ingrese una direcci� de correo completa: sunombre@sudominio.com");
        formField.focus();
        result = false;
    }

  return result;

}

function validNum(formField,fieldLabel,required)
{
    var result = true;

    if (required && !validRequired(formField,fieldLabel))
        result = false;

     if (result)
     {
         if (!allDigits(formField.value))
         {
             alert('EL campo "' + fieldLabel +'" es num�ico.');
            formField.focus();
            result = false;
        }
    }

    return result;
}


function validInt(formField,fieldLabel,required)
{
    var result = true;

    if (required && !validRequired(formField,fieldLabel))
        result = false;

     if (result)
     {
         var num = parseInt(formField.value,10);
         if (isNaN(num))
         {
             alert('El campo "' + fieldLabel +'" es num�ico.');
            formField.focus();
            result = false;
        }
    }

    return result;
}


function validDate(formField,fieldLabel,required)
{
    var result = true;

    if (required && !validRequired(formField,fieldLabel))
	result = false;

     if (result)
     {
	 var elems = formField.value.split("-");

	 result = (elems.length == 3); // should be three components

	 if (result)
	 {
	     var month = parseInt(elems[1],10);
              var day = parseInt(elems[2],10);
	     var year = parseInt(elems[0],10);
            result = allDigits(elems[0]) && (month > 0) && (month < 13) &&
		     allDigits(elems[1]) && (day > 0) && (day < 32) &&
		     allDigits(elems[2]) && ((elems[2].length == 2) || (elems[2].length == 4));
         }

	  if (!result)
	 {
	     alert('El formato de fecha debe ser AAAA-MM-DD en el campo "' + fieldLabel +'".');
	    formField.focus();
	}
    }

    return result;
}

function validExtensions(formfield,fieldLabel,extensions) {
	var result = true;
		if (formfield.value != '') {
			var extension = formfield.value.split(".");
			var elementos = extension.length;	
			if(elementos <= 1) {
				alert('El tipo de archivo en el campo "' + fieldLabel + '" es incorrecto.  El archivo debe ser de tipo: "' + extensions + '"');
				result = false;
				formfield.focus();
			}
			else {
				var extFile = extension[elementos-1];
				var extPerm = extensions.split(",");
				var correcto = 0;
				for(i=0; i<extPerm.length; i++) {
					if(extPerm[i] == extFile.toLowerCase()) {
						var correcto = 1;
					}
				}
				if(correcto == 0) {
					alert('El tipo de archivo en el campo "' + fieldLabel + '" es incorrecto.  El archivo debe ser de tipo: "' + extensions + '"');
					formfield.focus();
					result = false;
				
				}
			}
		}
	return result;
}

function requiredCheckbox(formfield,fieldLabel) {
	if (formfield.checked == false)
		alert('Debe marcar la casilla "' + fieldLabel + '" para continuar');
	return false;
	
	return true;
}