// JavaScript Document
function checkers(f){
	if(f.url.value=='' || f.url.value.length <= 3){
		alert('Complete Name seems incorrect');
		f.completename.focus();
		return false;
	}
	if(f.comments.value=='' || f.comments.value.length <= 3){
		alert('comments Name seems incorrect');
		f.comments.focus();
		return false;
	}
	if(f.email.value!=""){
		emailStr=f.email.value;
		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) {
			alert("Email address seems incorrect. Check @ and .");
			f.email.focus();
			return false;
		}	
		var user=matchArray[1];
		var domain=matchArray[2];
		
		// See if "user" is valid 
		if (user.match(userPat)==null) {
		    alert("The username doesn't seem to be valid.");
			f.email.focus();
		    return false;
		}
		
		var IPArray=domain.match(ipDomainPat);
		if (IPArray!=null) {
			for (var i=1;i<=4;i++) {
				if (IPArray[i]>255) {
			        alert("Destination IP address is invalid!");
					f.email.focus();
					return false;
			    }
	   	 	}
	   		return true;
		}	
	
		var domainArray=domain.match(domainPat);
		if (domainArray==null) {
			alert("The domain name doesn't seem to be valid.");
			f.email.focus();
		    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) {
	   		alert("The address must end in a three-letter domain, or two letter country.");
			f.email.focus();
		   	return false;
		}
	
		if (len<2) {
		   var errStr="This address is missing a hostname!";
		   alert(errStr);
		   f.email.focus();
		   return false;
		}
	}
}