var bugchars = '!#$^&*()+|}{[]?><~%:;/,=`"\'';

function CharsInBag(s){
	var i;
	var lchar="";
    // Search through string's characters one by one.
    // If character is not in bag.
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);
		if(i>0)lchar=s.charAt(i-1)
        if (bugchars.indexOf(c) != -1 || (lchar=="." && c==".")) return false;
    }
    return true;
}

function isInteger(s){
	var i;
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character is not a number.
        var c = s.charAt(i);
        if ((c >= "0") && (c <= "9") && (c != ".")) return false;
    }
    // All characters are numbers.
    return true;
}

function echeck(str) {
	var at="@"
	var dot="."
	var lat=str.indexOf(at)
	var lstr=str.length
	var ldot=str.indexOf(dot)
	var lastdot=str.lastIndexOf(dot)
	if (str.indexOf(at)==-1){
	   alert("e-mail invalido")
	   return false
	}
	if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
	   alert("e-mail invalido")
	   return false
	}
	if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr || str.substring(lastdot+1)==""){
		alert("e-mail invalido")
		return false
	}
	 
	 if (str.indexOf(at,(lat+1))!=-1){
		alert("e-mail invalido")
		return false
	 }

	 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
		alert("e-mail invalido")
		return false
	 }

	 if (str.indexOf(dot,(lat+2))==-1){
		alert("e-mail invalido")
		return false
	 }
	
	 if (str.indexOf(" ")!=-1){
		alert("e-mail invalido")
		return false
	 }
	if(CharsInBag(str)==false){
		alert("e-mail invalido")
		return false
	 }
	 var arrEmail=str.split("@")
	 var ldot=arrEmail[1].indexOf(".")
	 if(isInteger(arrEmail[1].substring(ldot+1))==false){
		alert("e-mail invalido")
		return false
	 }
	 return true					
}
	
function Validar(){
	var nombre=document.contact.nombre
	var coment=document.contact.comentario
	var emailID=document.contact.email
	
	if ((nombre.value==null)||(nombre.value=="")){
		alert("Por favor, introduzca un nombre")
		nombre.focus()
		return false	
	}

	if ((emailID.value==null)||(emailID.value=="")){
		alert("Por favor, introduzca un e-mail")
		emailID.focus()
		return false
	}
	if (echeck(emailID.value)==false){
		emailID.value=""
		emailID.focus()
		return false
	}
	
	if ((coment.value==null)||(coment.value=="")){
		alert("Por favor, introduzca un comentario")
		coment.focus()
		return false	
	}
	
	return true
}

function Validar_mail(){
	var mailID=document.news.mailnews
	
	if ((mailID.value==null)||(mailID.value=="")){
		alert("Por favor, introduzca un e-mail")
		mailID.focus()
		return false
	}
	if (echeck(mailID.value)==false){
		mailID.value=""
		mailID.focus()
		return false
	}
	
	return true
 }