package Encode::JP::JIS7;

use strict;

use warnings;

our $VERSION = do { my @r = ( q$Revision: 2.8 $ =~ /\d+/g ); sprintf "%d." . "%02d" x $#r, @r };

use Encode qw(:fallbacks);

for my $name ( '7bit-jis', 'iso-2022-jp', 'iso-2022-jp-1' ) {

    my $h2z     = ( $name eq '7bit-jis' )    ? 0 : 1;

    my $jis0212 = ( $name eq 'iso-2022-jp' ) ? 0 : 1;

    my $obj = bless {

        Name    => $name,

        h2z     => $h2z,

        jis0212 => $jis0212,

    } => __PACKAGE__;

    Encode::define_encoding($obj, $name);

}

use parent qw(Encode::Encoding);

# we override this to 1 so PerlIO works

sub needs_lines { 1 }

use Encode::CJKConstants qw(:all);

#

# decode is identical for all 2022 variants

#

sub decode($$;$) {

    my ( $obj, $str, $chk ) = @_;

    return undef unless defined $str;

    my $residue = '';

    if ($chk) {

        $str =~ s/([^\x00-\x7f].*)$//so and $residue = $1;

    }

    $residue .= jis_euc( \$str );

    $_[1] = $residue if $chk;

    return Encode::decode( 'euc-jp', $str, FB_PERLQQ );

}

#

# encode is different

#

sub encode($$;$) {

    require Encode::JP::H2Z;

    my ( $obj, $utf8, $chk ) = @_;

    return undef unless defined $utf8;

    # 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-jp', $utf8, $chk || 0 );

    $h2z and &Encode::JP::H2Z::h2z( \$octet );

    euc_jis( \$octet, $jis0212 );

    return $octet;

}

#

# cat_decode

#

my $re_scan_jis_g = qr{

   \G ( ($RE{JIS_0212}) |  $RE{JIS_0208}  |

        ($RE{ISO_ASC})  | ($RE{JIS_KANA}) | )

      ([^\e]*)

}x;

sub cat_decode {    # ($obj, $dst, $src, $pos, $trm, $chk)

    my ( $obj, undef, undef, $pos, $trm ) = @_;    # currently ignores $chk

    my ( $rdst, $rsrc, $rpos ) = \@_[ 1, 2, 3 ];

    local ${^ENCODING};

    use bytes;

    my $opos = pos($$rsrc);

    pos($$rsrc) = $pos;

    while ( $$rsrc =~ /$re_scan_jis_g/gc ) {

        my ( $esc, $esc_0212, $esc_asc, $esc_kana, $chunk ) =

          ( $1, $2, $3, $4, $5 );

        unless ($chunk) { $esc or last; next; }

        if ( $esc && !$esc_asc ) {

            $chunk =~ tr/\x21-\x7e/\xa1-\xfe/;

            if ($esc_kana) {

                $chunk =~ s/([\xa1-\xdf])/\x8e$1/og;

            }

            elsif ($esc_0212) {

                $chunk =~ s/([\xa1-\xfe][\xa1-\xfe])/\x8f$1/og;

            }

            $chunk = Encode::decode( 'euc-jp', $chunk, 0 );

        }

        elsif ( ( my $npos = index( $chunk, $trm ) ) >= 0 ) {

            $$rdst .= substr( $chunk, 0, $npos + length($trm) );

            $$rpos += length($esc) + $npos + length($trm);

            pos($$rsrc) = $opos;

            return 1;

        }

        $$rdst .= $chunk;

        $$rpos = pos($$rsrc);

    }

    $$rpos = pos($$rsrc);

    pos($$rsrc) = $opos;

    return '';

}

# JIS<->EUC

my $re_scan_jis = qr{

   (?:($RE{JIS_0212})|$RE{JIS_0208}|($RE{ISO_ASC})|($RE{JIS_KANA}))([^\e]*)

}x;

sub jis_euc {

    local ${^ENCODING};

    my $r_str = shift;

    $$r_str =~ s($re_scan_jis)

    {

    my ($esc_0212, $esc_asc, $esc_kana, $chunk) =

       ($1, $2, $3, $4);

    if (!$esc_asc) {

        $chunk =~ tr/\x21-\x7e/\xa1-\xfe/;

        if ($esc_kana) {

        $chunk =~ s/([\xa1-\xdf])/\x8e$1/og;

        }

        elsif ($esc_0212) {

        $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);

    local ${^ENCODING};

    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{JIS_0212} :

            $ESC{JIS_0208};

        if ($esc eq $ESC{JIS_0212} && !$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{JIS_0212}\E|\Q$ESC{JIS_0208}\E)/$1/gox;

    $$r_str;

}

1;

__END__

=head1 NAME

Encode::JP::JIS7 -- internally used by Encode::JP

=cut