// Documento JavaScript
function createRequestObject() {

   var req;

   if(window.XMLHttpRequest){
      // Firefox, Safari, Opera...
      req = new XMLHttpRequest();
   } else if(window.ActiveXObject) {
      // Internet Explorer 5+
      req = new ActiveXObject("Microsoft.XMLHTTP");
   } else {
      // There is an error creating the object,
      // just as an old browser is being used.
      alert('Su navegador no soporta AJAX.');
   }

   return req;

}

// Make the XMLHttpRequest object
var http = createRequestObject();

function is_empty(value) {
	if(value==null || value==0) {
		return true;
	}
	return (value=="");
}

function validar_fecha(fecha) {
	if (fecha != undefined && fecha != "" ) {
		if (!/^\d{2}\/\d{2}\/\d{4}$/.test(fecha)) {
			return false;
		}
		
		var dia  =  parseInt(fecha.substring(0,2),10);
		var mes  =  parseInt(fecha.substring(3,5),10);
		var anio =  parseInt(fecha.substring(6),10);

		switch(mes){
			case 1: case 3: case 5: case 7:	case 8: case 10: case 12:
				numDias=31;
				break;
			case 4: case 6: case 9: case 11:
				numDias=30;
				break;
			case 2:
				if (comprobarSiBisisesto(anio)){ 
					numDias=29 
				}else{ 
					numDias=28
				};
				break;
			default:
				return false;
		}

		if (dia>numDias || dia==0) {
			return false;
		}

		return true;
	}
}

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

function enviar_formulario(form) {

	formulario = form;
	var variables = "";
	var bandera = 0;

	for(i=0;i<eval("document." + formulario + ".elements.length");i++){
		campo = eval("document." + formulario + ".elements[i].name");
		if(eval("document." + formulario + ".elements[i].type != 'button'") && eval("document." + formulario + ".elements[i].type != 'reset'")){
			if(eval("document." + formulario + ".elements[i].type == 'radio'")){
				for (f=0;f<eval("document." + formulario + "." + campo + ".length");f++){
					if (eval("document." + formulario + "." + campo + "[f].checked")) 
						break;
				}
				valor = escape(eval("document." + formulario + "." + campo + "[f].value"));
			}else{
				valor = escape(eval("document." + formulario + ".elements[i].value"));
			}		
		
			if(bandera == 0){
				variables += campo + "=" + valor;
			}else{
				variables += "&" + campo + "=" + valor;
			}
			bandera++;
		}
	}
	variables += "&check=" + campos;
			
	http.open('post', './' + destino, true);
	http.onreadystatechange = handleResponsemail;
	http.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
	http.send(variables);
	return false;
}

function handleResponsemail() {
	if(http.readyState == 4 && http.status == 200){
		var response = http.responseText;
		if(response) {
			for(i=0;i<eval("document." + formulario + ".elements.length");i++){
				if(eval("document." + formulario + ".elements[i].type != 'button'") && eval("document." + formulario + ".elements[i].type != 'reset'") && eval("document." + formulario + ".elements[i].type != 'radio'")){
					eval("document." + formulario + ".elements[i].value = ''");
				}
			}
			document.getElementById("box").innerHTML = response;
		}
	} else {
		document.getElementById("box").innerHTML = "<strong>Enviando datos...</strong>";
	}
}