#!/usr/bin/perl -w
use HTML::Template;
use CGI::Simple;
use Data::FormValidator;
use Data::FormValidator::Constraints qw(:closures FV_length_between FV_min_length FV_max_length);


sub display_virgin_site;
sub func2;
sub check_missings;



my $cgi = new CGI::Simple;

#initial invocation of the site. Just display the empty form.
if ( scalar($cgi->param)==0 ) {
    display_virgin_site();
} else{
    check_missings();
}

sub display_virgin_site
{
  # open the html template
  my $template = HTML::Template->new( filename => 'main.html' );
  
  # send the obligatory Content-Type and print the template output
  print( "Content-Type: text/html\n\n", $template->output );
}

sub check_missings
{
  my $profile_obj = Data::FormValidator->new('criteria.pl');
  
  my $results = $profile_obj->check($cgi,'profil_name_1');
  
  if($results->success()){
    &func2();
  } else{
    my %cgiHash = $cgi->Vars();
    my $errhash = $results->msgs();
    # open the html template
    my $template = HTML::Template->new( filename => 'main.html' );
    @used_keys = qw(
                  lastname         
                  phone            
                  mobile           
                  email            
    );
    
    #filter error variables to items from array @used_keys
    my %clearedHash;
    foreach(@used_keys){
      $clearedHash{'error_'.$_} = $errhash->{'error_'.$_};     
    }
    $template->param(\%clearedHash);
    
    #clear hash before second usage
    %clearedHash=();
    foreach(@used_keys){
      $clearedHash{$_} = $cgiHash{$_};     
    }
    $template->param(\%clearedHash);
    
    print( "Content-Type: text/html\n\n", $template->output );
}

use Data::FormValidator::Constraints qw(:closures FV_length_between FV_min_length FV_max_length);
use Data::FormValidator::Filters;
 {  profil_name_1 => {
    required => [qw( 
                    lastname         
                   )
    ],
    # Entferne alle führenden und folgenden Leerstellen von den Werten der Formularfelder
    filters       => ['trim'],
    field_filter_regexp_map => {
       qr/(?:phone|mobile)$/    => sub {
                                                  my $value =  shift;
                                                  $value   =~ s§[-/ ]§§g;#Entferne Füllzeichen '/', '-' ' ' aus Telefonnummern
                                                  return $value;
                                                 },
    },
    # alle Felder deren name mit regexp übereinstimmen, bekommen passenden validator zugewiesen
    constraint_method_regexp_map => {
                                                                        # !Not like in doku on cpan with notation 'email' or 'email()'. That wouldn't work.  
      qr/email$/                                                   => [email(),FV_length_between(6,50)],
      qr/lastname$/                                                => FV_length_between(2,30)
    },
    msgs => {
  
       # Präfix für Variablen des Formulars die fehlerhaft sind erhalten Namensschema error_<name> 
       prefix=> 'error_',
  
       # Fehlertext für Variablen die als Required markiert waren erhalten diesen Fehlertext als Wert, welcher unten im format Schlüssel als %s Argument eingefügt wird
       missing => 'This value is required',
  
       # Fehlertext für Variablen, welche eine der Bedingungen, die für Sie definiert wurden verletzt haben
       invalid => 'Invalid value inserted',
  
       # Trennzeichenkette für das auftreteten von mehreren Bedingungsverletzungen für eine Variable aus dem Formular
       invalid_separator => "<br>\n",
  
       # Die Variablen mit Namensschema error_<name> bekommen diesen Fehlertext als Wert zugewiesen. %s ist entweder der Wert von missing oder von invalid
       format => '<span class="hint">%s</span>',
  
       # if a constraint is violated with one of this names, than create a custom error mmessage instead of the text in format.
       # length_between is the inlined name of FV_length_between(x,y). Just use the subname without brackets and params as name.
       constraints => {
                       'length_between' => 'To short or to long',
                       'email'          => 'Not a valid email adress',
       },
  
       # if any error is returned by msgs function then hash key 'errorflag' will be defined aka gets value 1
       any_errors => 'errorflag',
    }
  }
}

<!DOCTYPE html>
<html lang="en">
  <head>
    <!-- HTML 5 -->
    <title>Titel der Seite</title>
    <meta http-equiv="content-type" content="text/html; charset=utf-8">
  </head>
  <body>
    <form action="form.cgi" method="post">
        <table>
          <tr>
            <td>
              <label for="lastname">last name</label>
            </td>
            <td>
              <input name="lastname" size="20" maxlength="30" type="text" id="lastname" value="<TMPL_VAR ESCAPE=HTML NAME="lastname">"><TMPL_VAR NAME="error_lastname">
            </td>
          </tr>
          <tr>
            <td>  
              <label for="phone">phone</label>
            </td>
            <td>
              <input name="phone" size="11" maxlength="11" type="tel" id="phone" value="<TMPL_VAR ESCAPE=HTML NAME="phone">"><TMPL_VAR NAME="error_phone">
            </td>
          </tr>
          <tr>
            <td>  
              <label for="mobile">mobile</label>
            </td>
            <td>
              <input name="mobile" size="11" maxlength="11" type="tel" id="mobile" value="<TMPL_VAR ESCAPE=HTML NAME="mobile">"><TMPL_VAR NAME="error_mobile">
            </td>
          </tr>
          <tr>
            <td>  
              <label for="email">email</label>
            </td>
            <td>
              <input name="email" size="11" maxlength="11" type="email" id="email" value="<TMPL_VAR ESCAPE=HTML NAME="email">"><TMPL_VAR NAME="error_email">
            </td>
          </tr>
        </table>
    </form>
  </body>
</html>