var MESSAGE_USERNAME_REQUIRED = "Please enter the username.";
 var MESSAGE_PASSWORD_REQUIRED = "Please enter the password."; 
 var MESSAGE_PASSWORD_CONFIRM = "Password and confirmation must coincide. Please retype password and confirmation.";  
 var MESSAGE_EMAIL_REQUIRED = "Please enter a valid email address.";
 var MESSAGE_USERNAME_USED = "The username is already in use. Please enter a different username.";

 function HDW_locate_field(item,form)
 {
    for(i=0;i < form.elements.length;i++) 
        if (form.elements[i].name == item)  
          return i;
    return -1;    
 }

 function HDW_validate_registration(form)
 {
     var username_f = form.hdwusername.value;
	 var password_f = form.hdwpassword.value;
	 var passwordc_f = form.hdwconfirm.value;
	 var password_f = form.hdwpassword.value;
	 var activationemail_f = form.hdwactivation_email.value;
	 
	 if (form.elements[HDW_locate_field(username_f,form)].value == '')
	 {
	     alert(MESSAGE_USERNAME_REQUIRED);
		 return false;
	 }
	 if (form.elements[HDW_locate_field(password_f,form)].value == '')
	 {
	     alert(MESSAGE_PASSWORD_REQUIRED);
		 return false;
	 }
	 if (passwordc_f != '' && form.elements[HDW_locate_field(password_f,form)].value != form.elements[HDW_locate_field(passwordc_f,form)].value)
	 {
	     alert(MESSAGE_PASSWORD_CONFIRM);
		 return false;
	 }	 
	 if (activationemail_f != '')
	 {
	     var email = form.elements[HDW_locate_field(activationemail_f,form)].value;
		 if (email.indexOf("@")<1)
		 {
  	         alert(MESSAGE_EMAIL_REQUIRED);
 		     return false;
		 } 
	 }		 	 
	 return HDW_verify_username(form);
 }
 
 function HDW_verify_username(form)
 {
     var username_f = form.hdwusername.value;
     var table = form.hdwtablename.value;
     http_request = HDW_getRequest();   
     http_request.open("GET", "/HDWRegistrationAndLogin/verify_username.php?table="+table+"&field="+username_f+"&username="+form.elements[HDW_locate_field(username_f,form)].value, false);
     http_request.send(null);
     var text = http_request.responseText;
     if (text == 'OK')               
         return true;                
     else if (text == 'USED')               
     {
         alert(MESSAGE_USERNAME_USED);
         return false;
     }
     else
         return true;
 }
  
 function HDW_logout()
 {
     http_request = HDW_getRequest();   
     http_request.open("GET", "/HDWRegistrationAndLogin/logout.php", false);
     http_request.send(null);
     var text = http_request.responseText;
     document.location.reload(true);
 }
 
 function HDW_verify_Login(form)
 {
     var username_v = form.username.value;
     var password_v = form.password.value;
     var table = form.hdwtable.value;
     http_request = HDW_getRequest();   
     http_request.open("GET", "/HDWRegistrationAndLogin/login.php?table="+table+"&username="+username_v+"&password="+password_v, false);
     http_request.send(null);
     var text = http_request.responseText;
     if (text == 'OK')               
         return true;                
     else
     {
         alert(text);
         return false;
     }
 }
  
 
function HDW_getRequest()
{
    http_request = false;
    if (window.XMLHttpRequest) { // Mozilla, Safari,...
       http_request = new XMLHttpRequest();
       if (http_request.overrideMimeType) {
       	// set type accordingly to anticipated content type
          //http_request.overrideMimeType('text/xml');
          http_request.overrideMimeType('text/html');
       }
    } else if (window.ActiveXObject) { // IE
       try {
          http_request = new ActiveXObject("Msxml2.XMLHTTP");
       } catch (e) {
          try {
             http_request = new ActiveXObject("Microsoft.XMLHTTP");
          } catch (e) {}
       }
    }
    if (!http_request) {
       alert('Cannot create XMLHTTP instance');
       return false;
    }
    return http_request;
}
function HDW_showILMP()
{
	var divlogin = document.getElementById("hdwdivlogin");
	divlogin.style.display = "none";
	var divlogin = document.getElementById("hdwdivILMP");
	divlogin.style.display = "";
	var divlogin = document.getElementById("hdwdivLink");
	divlogin.style.display = "none";
}
function HDW_showLogin()
{
	var divlogin = document.getElementById("hdwdivlogin");
	divlogin.style.display = "";
	var divlogin = document.getElementById("hdwdivILMP");
	divlogin.style.display = "none";
	var divlogin = document.getElementById("hdwdivLink");
	divlogin.style.display = "";
}
function HDW_submitILMP()
{
	 var email_v = document.getElementById("hdwILMPemail").value;
     var table = document.getElementById("hdwtable").value;
     http_request = HDW_getRequest();   
     http_request.open("GET", "/HDWRegistrationAndLogin/ilmp.php?table="+table+"&email="+email_v, false);
     http_request.send(null);
     var text = http_request.responseText;
     if (text == 'OK')               
         return true;                
     else
     {
         alert(text);
         return false;
     }
}