function checkEmail(emailStr) {
   var emailPat=/^(.+)@(.+)$/ 
   var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]" 
   var validChars="\[^\\s" + specialChars + "\]" 
   var quotedUser="(\"[^\"]*\")" 
   var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/
   var atom=validChars + '+'
   var word="(" + atom + "|" + quotedUser + ")"
   var userPat=new RegExp("^" + word + "(\\." + word + ")*$")
   var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$")
   var matchArray=emailStr.match(emailPat)
   
   if (matchArray==null) return false
   
   var user=matchArray[1]
   var domain=matchArray[2]
   
   if (user.match(userPat)==null) return false
   
   var IPArray=domain.match(ipDomainPat)
   if (IPArray!=null) {
   		for (var i=1;i<=4;i++) {
   			if (IPArray[i]>255) {
   				alert("IP de destino inválida")
   				return false
   			}
   		}
   		return true
   }
   
   var domainArray=domain.match(domainPat)
   if (domainArray==null) return false
   
   var atomPat=new RegExp(atom,"g")
   var domArr=domain.match(atomPat)
   var len=domArr.length
   if ((domArr[domArr.length-1].length<2) || (domArr[domArr.length-1].length>3)) return false;
   
   if (len<2) return false
   
   return true;
}


function Validar(form)
{

if (form.titulo.value == "")
{ alert("Ingrese el titulo de la obra"); form.titulo.focus(); return; }
if (form.nombre.value == "")
{ alert("Ingrese el nombre del artista"); form.nombre.focus(); return; }
if (form.pais.value == "0")
{ alert("Seleccione la nacionalidad del artista"); form.pais.focus(); return; }
if (form.direccion.value == "")
{ alert("Ingrese la direccion del artista"); form.direccion.focus(); return; }
if (form.telefono.value == "")
{ alert("Ingrese el telefono del artista"); form.telefono.focus(); return; }
if (form.email.value == "")
{ alert("Ingrese su e-mail"); form.email.focus(); return; }
if (!checkEmail(form.email.value))
{ alert("Ingrese su e-mail correctamente"); form.email.focus(); return; }
if (form.duracion.value == "")
{ alert("Ingrese la duración de su obra"); form.duracion.focus(); return; }

  form.submit();
}




function GeneraHoja(url_pop)
    {
     var PopWidth=600;
     var PopHeight=400;
     var PopLeft = (window.screen.width-PopWidth)/2;
     var PopTop = (window.screen.height-PopHeight)/2;
    
     imprimir=window.open(url_pop,'imprimir','toolbar=no,status=yes,menubar=no,location=no,directories=no,resizable=yes,scrollbars=yes,width='+PopWidth+',height='+PopHeight+',top='+PopTop+',left='+PopLeft);
     }
     
  function PopWidnow(url_pop)
    {
     var PopWidth=1;
     var PopHeight=1;
     var PopLeft = (window.screen.width-PopWidth)/2;
     var PopTop = (window.screen.height-PopHeight)/2;
    
     Muestas=window.open(url_pop,'Muestas','toolbar=no,status=no,menubar=no,location=no,directories=no,resizable=no,scrollbars=yes,width='+PopWidth+',height='+PopHeight+',top='+PopTop+',left='+PopLeft);
     }