###########################################################################
package Netfax::Grammar;
###########################################################################

# $Id: Grammar.pm,v 1.3 2003/12/09 18:35:28 lcampos Exp $

use strict;
use warnings;
our( $VERSION, @ISA, @EXPORT, @EXPORT_OK, %EXPORT_TAGS );

BEGIN{
  use Exporter;
  $VERSION = do{my@r=(q$Revision: 1.3 $=~/\d+/g);sprintf"%d."."%02d"x$#r,@r};
  use base qw( Exporter );
}

@EXPORT_OK = qw( $command_line $subject_spec
		 $telephone_list $option $option_spec
		 $from_spec $domainname_spec $username_spec
	       );

###########################################################################
# Gramatica para capturar linha de comando (RFC822 "Subject:")
my $time_spec    = qr{
		      # Hora: dois digitos codificando numeros de 00 a 23.
		      (?:[01]\d|2[0-3])
		      # Dois pontos, separador de hora/min, opcional.
		      :?
		      # Minutos: dois digitos, codificando minutos de 00 a 59
		      [0-5]\d}x;
my $day_spec     = qr{
		      # Dias de 01 a 09
		      0[1-9]
		      |
		      # Dias de 10 a 29
		      [12][0-9]
		      |
		      # Dias 30 e 31.
		      3[01]
		     }x;
my $month_spec   = qr{
		      # Meses de 01 a 09
		      0[1-9]
		      |
		      # Meses 10, 11 e 12
		      1[012]
		     }x;
my $year_spec    = qr{
		      # Seculo vinte, apenas
		      20
		      # Decadas: de 03 a 99.
		      (?:0[3-9]|[1-9]\d)
		     }x;
my $date_sep     = qr{
		      # Separadores validos sao '.' e '-'.
		      (?:\.|-)
		     }x;
my $date_spec    = qr{
		      # Dia, de 01 a 31.
		      $day_spec
		      # Separador de data, opcional.
		      $date_sep?
		      # Mes, de 01 a 12.
		      $month_spec
		      # Separador de data, opcional.
		      $date_sep?
		      # Ano, de 2003 a 2099.
		      $year_spec
		     }x;
our $option       = qr{
		      # Todas as opcoes comecam com '/'
		      /
		      (?:
		       # IMO ou IM
		       [Ii][Mm][Oo]?     |
		       # NSIM ou SIM
		       [Nn]?[Ss][Ii][Mm] |
		       # D (data)
		       [Dd]$date_spec    |
		       # H (hora)
		       [Hh]$time_spec
		      )
		     }x;
# Captura o valor passado como argumento em algumas opcoes.
our $option_spec = qr{
		      # Todas as opcoes comecam com '/'
		      /
		      (?:
		       # IMO ou IM
		       ([Ii][Mm][Oo])?     |
		       # NSIM ou SIM
		       ([Nn]?[Ss][Ii][Mm]) |
		       # D (data)
		       [Dd]($date_spec)    |
		       # H (hora)
		       [Hh]($time_spec)
		      )
		     }x;
my $option_list  = qr{
		      # lista de opcoes:
		      (?:
		       # uma opcao
		       $option
		       # seguida de zero ou mais espacos
		       \s*
		       # tantas vezes quantas se puder encontrar.
		      )*
		     }x;
my $phone        = qr{
		      (?:
		       # Caracteres '-', '+', '(', ')', '.', '0-9',
		       # 'a-z', 'A-Z', '_'
		       [-+\(\)\.\w]
		       # ou
		       |
		       # todo espaco em branco (' ') nao seguido de virgula
		       \ (?!,)
		       # obrigatoriamente uma vez, e
		       # tantas mais quantas voce conseguir.
		      )+
		     }x;
my $phone_list   = qr{ $phone(?:(?:\s*,\s*)$phone)* }x;

# Linha de comando: captura a lista de telefones
# e a lista de opcoes separadamente.
our $command_line = qr{($phone_list)\s*($option_list)}x;

our $subject_spec = qr{^[Ss][Uu][Bb][Jj][Ee][Cc][Tt]:\s*$command_line}x;
# Fim das Regras
###########################################################################


###########################################################################
# Regras para capturar telefones de uma lista de telefones

our $telephone_list = qr{($phone)(?:\s*,\s*)?}x;

# Fim das Regras
###########################################################################

###########################################################################
# Regras para capturar o RFC822 "From:" de um email

our $username_spec = qr{
		       # Username
		       [A-Za-z0-9_.-]+
		      }x;

our $domainname_spec = qr;(?:$username_spec\.)+[A-Za-z]{2,4};x;

our $from_spec = qr{
		    $username_spec
		    # "at"
		    @
		    $domainname_spec
		   }x;

# Fim das Regras
###########################################################################
1;__END__