package Encode::JIS2K::2022JP3;
use strict;

our $VERSION = do { my @r = (q$Revision: 0.03 $ =~ /\d+/g); sprintf "%d."."%02d" x $#r, @r };

use Encode qw(:fallbacks);

use base qw(Encode::Encoding);

my $Canon = 'iso-2022-jp-3';
$Encode::Encoding{$Canon} =
    bless {
          Name      =>   $Canon,
	   h2z       =>   1,
	   jis0212   =>   1,
	  } => __PACKAGE__;

# we override this to 1 so PerlIO works
sub needs_lines { 1 }

use Encode::CJKConstants qw(:all);

our $DEBUG = 0;

#
# decode is identical for all 2022 variants
#

sub decode($$;$)
{
    my ($obj, $str, $chk) = @_;
    my $residue = '';
    if ($chk){
	$str =~ s/([^\x00-\x7f].*)$//so;
	$1 and $residue = $1;
    }
    $residue .= jis_euc(\$str);
    $_[1] = $residue if $chk;
    return Encode::decode('euc-jisx0213', $str, FB_PERLQQ);
}

#
# encode is different
#

sub encode($$;$)
{
    require Encode::JP::H2Z;
    my ($obj, $utf8, $chk) = @_;
    # empty the input string in the stack so perlio is ok
    $_[1] = '' if $chk;
    my ($h2z, $jis0212) = @$obj{qw(h2z jis0212)};
    my $octet = Encode::encode('euc-jisx0213', $utf8, FB_PERLQQ) ;
    $h2z and &Encode::JP::H2Z::h2z(\$octet);
    euc_jis(\$octet, $jis0212);
    return $octet;
}



our $ESC_JISX0213_1 = "\e\$(O";
our $ESC_JISX0213_2 = "\e\$(P";

# JIS<->EUC

sub jis_euc {
    my $r_str = shift;
    $$r_str =~ s(
		 ($RE{JIS_0212}|$RE{JIS_0208}|$RE{ISO_ASC}|$RE{JIS_KANA})
		 ([^\e]*)
		 )
    {
	my ($esc, $chunk) = ($1, $2);
	if ($esc !~ /$RE{ISO_ASC}/o) {
	    $chunk =~ tr/\x21-\x7e/\xa1-\xfe/;
	    if ($esc =~ /$RE{JIS_KANA}/o) {
		$chunk =~ s/([\xa1-\xdf])/\x8e$1/og;
	    }
	    elsif ($esc =~ /$RE{JIS_0212}/o) {
		$chunk =~ s/([\xa1-\xfe][\xa1-\xfe])/\x8f$1/og;
	    }
	}
	$chunk;
    }geox;
    my ($residue) = ($$r_str =~ s/(\e.*)$//so);
    return $residue;
}

sub euc_jis{
    no warnings qw(uninitialized);
    my $r_str = shift;
    my $jis0212 = shift;
    $$r_str =~ s{
	((?:$RE{EUC_C})+|(?:$RE{EUC_KANA})+|(?:$RE{EUC_0212})+)
	}{
	    my $chunk = $1;
	    my $esc =
		( $chunk =~ tr/\x8E//d ) ? $ESC{KANA} :
		    ( $chunk =~ tr/\x8F//d ) ? $ESC_JISX0213_2 :
			$ESC_JISX0213_1;
	    if ($esc eq $ESC_JISX0213_2 && !$jis0212){
		# fallback to '?'
		$chunk =~ tr/\xA1-\xFE/\x3F/;
	    }else{
		$chunk =~ tr/\xA1-\xFE/\x21-\x7E/;
	    }
	    $esc . $chunk . $ESC{ASC};
	}geox;
    $$r_str =~
	s/\Q$ESC{ASC}\E
	    (\Q$ESC{KANA}\E|\Q$ESC_JISX0213_1\E|\Q$ESC_JISX0213_2\E)/$1/gox;
    $$r_str;
}

1;
__END__


=head1 NAME

Encode::JIS2K::2022JP3 -- internally used by Encode::JIS2K

=cut