function focusForm() {
   document.getElementById("name").focus();
}

function markNeededLabels() {
   theform=document.getElementById("feedbackform");
   labels=theform.getElementsByTagName("label");
   for (j = 0; j < labels.length; ++j) {
      if (labels[j].className == "obligatory") {
         labels[j].innerHTML +="<span class=\"asterix\">&nbsp;*</span>";
      }
   }

}

function validateForm() {
   theform=document.getElementById("feedbackform"); 
   inputs=theform.getElementsByTagName("input");
   for (j = 0; j < inputs.length; ++j) {
      if (inputs[j].className=="oblig") {
         if (inputs[j].type == "radio") {
            sel=getRadio(theform.elements[inputs[j].name]); 
            if (sel == "") {
               inputs[j].focus();
               alert("A " + inputs[j].name + " must be chosen.");
               return false;
            }
         } else if (inputs[j].value == "") {
            inputs[j].focus();
            alert(inputs[j].name + " must be filled out.");
            return false;
         } else if (inputs[j].name == "Email") {
            if (validateEmail(inputs[j].value) == false) {
               inputs[j].focus();
               alert(inputs[j].name + " must be a valid e-mail address.");
               return false; 
            } 
         }
      }
   }

   texts=theform.getElementsByTagName("textarea");
   for (j = 0; j < texts.length; ++j) {
      if (texts[j].className=="oblig") {
         if (texts[j].value == ""){
            texts[j].focus();
            alert(texts[j].name + " must be filled out.");
            return false;
         }
      }
   }
   return true;
}

function getRadio(radioObj) {
   if(!radioObj) return "";
   var radioLength = radioObj.length;
   if(radioLength == undefined)
      if(radioObj.checked) return radioObj.value;
      else return "";
  
   for(var i = 0; i < radioLength; i++) {
      if(radioObj[i].checked) {
         return radioObj[i].value;
      }
   }
   return "";
}

function validateEmail(emailStr) {
   /* The following variable tells the rest of the function whether or not
   to verify that the address ends in a two-letter country or well-known
   TLD.  1 means check it, 0 means dont. */

   var checkTLD=1;

   /* The following is the list of known TLDs that an e-mail address must end with. */

   var knownDomsPat=/^(com|cat|jobs|mobi|travel|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum)$/;

   /* The following pattern is used to check if the entered e-mail address
   fits the user@domain format.  It also is used to separate the username
   from the domain. */

   var emailPat=/^(.+)@(.+)$/;

   /* The following string represents the pattern for matching all special
   characters.  We don't want to allow special characters in the address.
   These characters include ( ) < > @ , ; : \ " . [ ] */

   var specialChars="\\(\\)><@,;:\\\\\\\"\\.\\[\\]";

   /* The following string represents the range of characters allowed in a
   username or domainname.  It really states which chars aren't allowed.*/

   var validChars="\[^\\s" + specialChars + "\]";

   /* The following pattern applies if the "user" is a quoted string (in
   which case, there are no rules about which characters are allowed
   and which aren't; anything goes).  E.g. "jiminy cricket"@disney.com
   is a legal e-mail address. */

   var quotedUser="(\"[^\"]*\")";

   /* The following pattern applies for domains that are IP addresses,
   rather than symbolic names.  E.g. joe@[123.124.233.4] is a legal
   e-mail address. NOTE: The square brackets are required. */

   var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;

   /* The following string represents an atom (basically a series of non-special characters.) */

   var atom=validChars + '+';

   /* The following string represents one word in the typical username.
   For example, in john.doe@somewhere.com, john and doe are words.
   Basically, a word is either an atom or quoted string. */

   var word="(" + atom + "|" + quotedUser + ")";

   // The following pattern describes the structure of the user

   var userPat=new RegExp("^" + word + "(\\." + word + ")*$");

   /* The following pattern describes the structure of a normal symbolic
   domain, as opposed to ipDomainPat, shown above. */

   var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");

   /* Finally, let's start trying to figure out if the supplied address is valid. */

   /* Begin with the coarse pattern to simply break up user@domain into
   different pieces that are easy to analyze. */

   var matchArray=emailStr.match(emailPat);

   if (matchArray==null) {

   /* Too many/few @'s or something; basically, this address doesn't
   even fit the general mould of a valid e-mail address. */

   //alert("Email address seems incorrect (check @ and .'s)");
   return false;
   }
   var user=matchArray[1];
   var domain=matchArray[2];

   // Start by checking that only basic ASCII characters are in the strings (0-127).

   for (i=0; i<user.length; i++) {
   if (user.charCodeAt(i)>127) {
   //alert("Ths username contains invalid characters.");
   return false;
      }
   }
   for (i=0; i<domain.length; i++) {
   if (domain.charCodeAt(i)>127) {
   //alert("Ths domain name contains invalid characters.");
   return false;
      }
   }

   // See if "user" is valid

   if (user.match(userPat)==null) {

   // user is not valid

   //alert("The username doesn't seem to be valid.");
   return false;
   }

   /* if the e-mail address is at an IP address (as opposed to a symbolic
   host name) make sure the IP address is valid. */

   var IPArray=domain.match(ipDomainPat);
   if (IPArray!=null) {

   // this is an IP address

   for (var i=1;i<=4;i++) {
   if (IPArray[i]>255) {
   //alert("Destination IP address is invalid!");
   return false;
      }
   }
   return true;
   }

   // Domain is symbolic name.  Check if it's valid.

   var atomPat=new RegExp("^" + atom + "$");
   var domArr=domain.split(".");
   var len=domArr.length;
   for (i=0;i<len;i++) {
   if (domArr[i].search(atomPat)==-1) {
   //alert("The domain name does not seem to be valid.");
   return false;
      }
   }

   /* domain name seems valid, but now make sure that it ends in a
   known top-level domain (like com, edu, gov) or a two-letter word,
   representing country (uk, nl), and that there's a hostname preceding
   the domain or country. */

   if (checkTLD && domArr[domArr.length-1].length!=2 &&
   domArr[domArr.length-1].search(knownDomsPat)==-1) {
   //alert("The address must end in a well-known domain or two letter " + "country.");
   return false;
   }

   // Make sure there's a host name preceding the domain.

   if (len<2) {
   //alert("This address is missing a hostname!");
   return false;
   }

   // If we've gotten this far, everything's valid!
   return true;
}