function emailCheck (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 don't. */

var checkTLD=1;

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

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

// See if "user" is valid 

if (user.match(userPat)==null) {
    // user is not valid
    return("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) {
    return("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) {
return("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) {
    return("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) {
    return("This address is missing a hostname!");
    //return false;
}

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


function checkClientRegForm(name_form){
var err = '';

                var f = document.forms[name_form];
                if(!f) {
                    alert('Wrong form!');
                    return false;
                }

                f.elements['client_name'].value = f.elements['client_billing_fname'].value + ' ' + f.elements['client_billing_lname'].value;

            //alert(emailCheck(f.client_email.value));
            if(emailCheck(f.client_email.value) != true)
            {   
                errm="";
                if( emailCheck(f.client_email.value)!= false)
                    errm = ": " + emailCheck(f.client_email.value); 
                
                err += "\n\tWrong value for Email"+errm;
            }

                if('' == f.elements['client_password'].value) 
                {
                    err += "\n\tPassword is empty";
                }
                
                if(f.client_phone.value == '')
                {
                    err += "\n\tType your phone";
                }

                //if(f.client_birthday.value == '')
                //{
                //    err += "\n\tType your birthday";
                //}

                if(f.elements['client_billing_fname'].value == '') 
                {
                    err += "\n\tType your billing first name";
                }

                if(f.elements['client_billing_lname'].value == '') 
                {
                    err += "\n\tType your billing last name";
                }

                if(f.elements['client_shipping_fname'].value == '') 
                {
                    err += "\n\tType your shipping first name";
                }

                if(f.elements['client_shipping_lname'].value == '') 
                {
                    err += "\n\tType your shipping last name";
                }
                
                if(f.elements['client_billing_adress1'].value == '') 
                {
                    err += "\n\tType your billing address1";
                }
    
                if(f.elements['client_billing_city'].value == '') 
                {
                    err += "\n\tType your billing city";
                }

                if(f.elements['client_billing_zip'].value == '') 
                {
                    err += "\n\tType your billing zip";
                }

                if(f.elements['client_billing_phone'].value == '') 
                {
                    err += "\n\tType your billing phone number";
                }

                if(err != '') 
                {
                    alert("You haven't fill all required fields:\n"+err);
                    return false;
                }
                return true;


}


//****************************************************************************************************************

            function getRadioValue(f, rkey)
            {
                for(i=0; i<f.elements[rkey].length;i++)
                {
                    if(true == f.elements[rkey][i].checked)
                    {
                        resolution = f.elements[rkey][i].value;
                        return f.elements[rkey][i].value;
                    }
                }
                return -1;
            }


//****************************************************************************************************************

            function validateclient(name_form) 
            {
                var f = document.forms[name_form];
                if(!f) {
                    alert('Wrong form!');
                    return false;
                }
    
                err = '';
                if(f.elements['client_name'].value == '') 
                {
                    err += "\n\tType your name";
                }
    
            //var re = new RegExp("^[a-zA-Z]+[0-9a-zA-Z_]+@[0-9a-zA-Z]+[\.][a-zA-Z]+$");
            //if(re.exec(f.client_email.value) == null)
            //{
            //        err += "\n\tWrong value for Email";
            //}

                if(f.elements['client_password'].value == '') 
                {
                    err += "\n\tType your password";
                }


                if(err != '') 
                {
                    alert("You haven't fill all required fields:\n"+err);
                    return false;
                }
                return true;
            }
            
//****************************************************************************************************************
            
            function checkForm(name_form) 
            {
                var f = document.forms[name_form];
                if(!f) {
                    alert('Wrong form!');
                    return false;
                }
    
                err = '';
                if(f.elements['client_name'].value == '') 
                {
                    err += "\n\tType your name";
                }
    
                var re = new RegExp("^[a-zA-Z]+[0-9a-zA-Z_]+@[0-9a-zA-Z]+[\.][a-zA-Z]+$");
                if(re.exec(f.client_email.value) == null)
                {
                        err += "\n\tWrong value for Email";
                }
    
                if('' == f.elements['client_password'].value) 
                {
                    err += "\n\tPassword is empty";
                }
                
                if(f.client_phone.value == '')
                {
                    err += "\n\tType your phone";
                }
                
                //if(f.elements['client_billing_name'].value == '') 
                //{
                //    err += "\n\tType your billing name";
                //}
                
                if(f.elements['client_billing_adress1'].value == '') 
                {
                    err += "\n\tType your billing address1";
                }
    
                if(f.elements['client_billing_city'].value == '') 
                {
                    err += "\n\tType your billing city";
                }

                if(f.elements['client_billing_zip'].value == '') 
                {
                    err += "\n\tType your billing zip";
                }

                if(f.elements['client_billing_phone'].value == '') 
                {
                    err += "\n\tType your billing phone number";
                }


                
                if(getRadioValue(f, "client_cctype") == -1)
                {
                    err += "\n\t Do not select Credit Card";
                }
                
                if(f.elements['client_ccnumber'].value == '') 
                {
                    err += "\n\tType your credit card number";
                }

                if(f.elements['client_cccvv'].value == '') 
                {
                    err += "\n\tType your cvv";
                }

                if(f.elements['client_ccholdername'].value == '') 
                {
                    err += "\n\tType Credit Card Owner";
                }




                if(err != '') 
                {
                    alert("You haven't fill all required fields:\n"+err);
                    return false;
                }
                return true;
            }


//******************************************************************

//****************************************************************************************************************
            
//****************************************************************************************************************
            
            function checkForm(name_form) 
            {
                var f = document.forms[name_form];
                if(!f) {
                    alert('Wrong form!');
                    return false;
                }
    
                err = '';
                if(f.elements['client_name'].value == '') 
                {
                    err += "\n\tType your name";
                }
    
                var re = new RegExp("^[a-zA-Z]+[0-9a-zA-Z_]+@[0-9a-zA-Z]+[\.][a-zA-Z]+$");
                if(re.exec(f.client_email.value) == null)
                {
                        err += "\n\tWrong value for Email";
                }
    
                if('' == f.elements['client_password'].value) 
                {
                    err += "\n\tPassword is empty";
                }
                
                if(f.client_phone.value == '')
                {
                    err += "\n\tType your phone";
                }
                
                if(f.elements['client_billing_name'].value == '') 
                {
                    err += "\n\tType your billing name";
                }
                
                if(f.elements['client_billing_adress1'].value == '') 
                {
                    err += "\n\tType your billing address1";
                }
    
                if(f.elements['client_billing_city'].value == '') 
                {
                    err += "\n\tType your billing city";
                }

                if(f.elements['client_billing_zip'].value == '') 
                {
                    err += "\n\tType your billing zip";
                }

                if(f.elements['client_billing_phone'].value == '') 
                {
                    err += "\n\tType your billing phone number";
                }


                

                if(err != '') 
                {
                    alert("You haven't fill all required fields:\n"+err);
                    return false;
                }
                return true;
            }


//******************************************************************

//****************************************************************************************************************
            

//****************************************************************************************************************
            
            function FullcheckForm(name_form) 
            {
                var f = document.forms[name_form];
                if(!f) {
                    alert('Wrong form!');
                    return false;
                }
    
                err = '';
                if(f.elements['client_name'].value == '') 
                {
                    err += "\n\tType your name";
                }
    
                var re = new RegExp("^[a-zA-Z]+[0-9a-zA-Z_]+@[0-9a-zA-Z]+[\.][a-zA-Z]+$");
                if(re.exec(f.client_email.value) == null)
                {
                        err += "\n\tWrong value for Email";
                }
    
                if('' == f.elements['client_password'].value) 
                {
                    err += "\n\tPassword is empty";
                }
                
                if(f.client_phone.value == '')
                {
                    err += "\n\tType your phone";
                }
                
                if(f.elements['client_billing_name'].value == '') 
                {
                    err += "\n\tType your billing name";
                }
                
                if(f.elements['client_billing_adress1'].value == '') 
                {
                    err += "\n\tType your billing address1";
                }
    
                if(f.elements['client_billing_city'].value == '') 
                {
                    err += "\n\tType your billing city";
                }

                if(f.elements['client_billing_zip'].value == '') 
                {
                    err += "\n\tType your billing zip";
                }

                if(f.elements['client_billing_phone'].value == '') 
                {
                    err += "\n\tType your billing phone number";
                }


                
                if(getRadioValue(f, "client_cctype") == -1)
                {
                    err += "\n\t Do not select Credit Card";
                }
                
                if(f.elements['client_ccnumber'].value == '') 
                {
                    err += "\n\tType your credit card number";
                }

                if(f.elements['client_cccvv'].value == '') 
                {
                    err += "\n\tType your cvv";
                }

                if(f.elements['client_ccholdername'].value == '') 
                {
                    err += "\n\tType Credit Card Owner";
                }




                if(err != '') 
                {
                    alert("You haven't fill all required fields:\n"+err);
                    return false;
                }
                return true;
            }


//******************************************************************

//****************************************************************************************************************