package CGI::Util;
use parent 'Exporter';
require 5.008001;
use strict;
our @EXPORT_OK = qw(rearrange rearrange_header make_attributes unescape escape
        expires ebcdic2ascii ascii2ebcdic);

our $VERSION = '4.51';

our $_EBCDIC = "\t" ne "\011";

my $appease_cpants_kwalitee = q/
use strict;
use warnings;
#/;

# (ord('^') == 95) for codepage 1047 as on os390, vmesa
our @A2E = (
   0,  1,  2,  3, 55, 45, 46, 47, 22,  5, 21, 11, 12, 13, 14, 15,
  16, 17, 18, 19, 60, 61, 50, 38, 24, 25, 63, 39, 28, 29, 30, 31,
  64, 90,127,123, 91,108, 80,125, 77, 93, 92, 78,107, 96, 75, 97,
 240,241,242,243,244,245,246,247,248,249,122, 94, 76,126,110,111,
 124,193,194,195,196,197,198,199,200,201,209,210,211,212,213,214,
 215,216,217,226,227,228,229,230,231,232,233,173,224,189, 95,109,
 121,129,130,131,132,133,134,135,136,137,145,146,147,148,149,150,
 151,152,153,162,163,164,165,166,167,168,169,192, 79,208,161,  7,
  32, 33, 34, 35, 36, 37,  6, 23, 40, 41, 42, 43, 44,  9, 10, 27,
  48, 49, 26, 51, 52, 53, 54,  8, 56, 57, 58, 59,  4, 20, 62,255,
  65,170, 74,177,159,178,106,181,187,180,154,138,176,202,175,188,
 144,143,234,250,190,160,182,179,157,218,155,139,183,184,185,171,
 100,101, 98,102, 99,103,158,104,116,113,114,115,120,117,118,119,
 172,105,237,238,235,239,236,191,128,253,254,251,252,186,174, 89,
  68, 69, 66, 70, 67, 71,156, 72, 84, 81, 82, 83, 88, 85, 86, 87,
 140, 73,205,206,203,207,204,225,112,221,222,219,220,141,142,223
     );
our @E2A = (
   0,  1,  2,  3,156,  9,134,127,151,141,142, 11, 12, 13, 14, 15,
  16, 17, 18, 19,157, 10,  8,135, 24, 25,146,143, 28, 29, 30, 31,
 128,129,130,131,132,133, 23, 27,136,137,138,139,140,  5,  6,  7,
 144,145, 22,147,148,149,150,  4,152,153,154,155, 20, 21,158, 26,
  32,160,226,228,224,225,227,229,231,241,162, 46, 60, 40, 43,124,
  38,233,234,235,232,237,238,239,236,223, 33, 36, 42, 41, 59, 94,
  45, 47,194,196,192,193,195,197,199,209,166, 44, 37, 95, 62, 63,
 248,201,202,203,200,205,206,207,204, 96, 58, 35, 64, 39, 61, 34,
 216, 97, 98, 99,100,101,102,103,104,105,171,187,240,253,254,177,
 176,106,107,108,109,110,111,112,113,114,170,186,230,184,198,164,
 181,126,115,116,117,118,119,120,121,122,161,191,208, 91,222,174,
 172,163,165,183,169,167,182,188,189,190,221,168,175, 93,180,215,
 123, 65, 66, 67, 68, 69, 70, 71, 72, 73,173,244,246,242,243,245,
 125, 74, 75, 76, 77, 78, 79, 80, 81, 82,185,251,252,249,250,255,
  92,247, 83, 84, 85, 86, 87, 88, 89, 90,178,212,214,210,211,213,
  48, 49, 50, 51, 52, 53, 54, 55, 56, 57,179,219,220,217,218,159
     );

if ($_EBCDIC && ord('^') == 106) { # as in the BS2000 posix-bc coded character set
     $A2E[91] = 187;   $A2E[92] = 188;  $A2E[94] = 106;  $A2E[96] = 74;
     $A2E[123] = 251;  $A2E[125] = 253; $A2E[126] = 255; $A2E[159] = 95;
     $A2E[162] = 176;  $A2E[166] = 208; $A2E[168] = 121; $A2E[172] = 186;
     $A2E[175] = 161;  $A2E[217] = 224; $A2E[219] = 221; $A2E[221] = 173;
     $A2E[249] = 192;

     $E2A[74] = 96;   $E2A[95] = 159;  $E2A[106] = 94;  $E2A[121] = 168;
     $E2A[161] = 175; $E2A[173] = 221; $E2A[176] = 162; $E2A[186] = 172;
     $E2A[187] = 91;  $E2A[188] = 92;  $E2A[192] = 249; $E2A[208] = 166;
     $E2A[221] = 219; $E2A[224] = 217; $E2A[251] = 123; $E2A[253] = 125;
     $E2A[255] = 126;
   }
elsif ($_EBCDIC && ord('^') == 176) { # as in codepage 037 on os400
  $A2E[10] = 37;  $A2E[91] = 186;  $A2E[93] = 187; $A2E[94] = 176;
  $A2E[133] = 21; $A2E[168] = 189; $A2E[172] = 95; $A2E[221] = 173;

  $E2A[21] = 133; $E2A[37] = 10;  $E2A[95] = 172; $E2A[173] = 221;
  $E2A[176] = 94; $E2A[186] = 91; $E2A[187] = 93; $E2A[189] = 168;
}

# Smart rearrangement of parameters to allow named parameter
# calling.  We do the rearrangement if:
# the first parameter begins with a -

sub rearrange {
    my ($order,@param) = @_;
    my ($result, $leftover) = _rearrange_params( $order, @param );
    push @$result, make_attributes( $leftover, defined $CGI::Q ? $CGI::Q->{escape} : 1 ) 
    if keys %$leftover;
    @$result;
}

sub rearrange_header {
    my ($order,@param) = @_;

    my ($result,$leftover) = _rearrange_params( $order, @param );
    push @$result, make_attributes( $leftover, 0, 1 ) if keys %$leftover;

    @$result;
}

sub _rearrange_params {
    my($order,@param) = @_;
    return [] unless @param;

    if (ref($param[0]) eq 'HASH') {
    @param = %{$param[0]};
    } else {
    return \@param 
        unless (defined($param[0]) && substr($param[0],0,1) eq '-');
    }

    # map parameters into positional indices
    my ($i,%pos);
    $i = 0;
    foreach (@$order) {
    foreach (ref($_) eq 'ARRAY' ? @$_ : $_) { $pos{lc($_)} = $i; }
    $i++;
    }

    my %params_as_hash = ( @param );

    my (@result,%leftover);
    $#result = $#$order;  # preextend

    foreach my $k (
        # sort keys alphabetically but favour certain keys before others
        # specifically for the case where there could be several options
        # for a param key, but one should be preferred (see GH #155)
        sort {
            if    ( $a =~ /content/i ) { return 1 }
            elsif ( $b =~ /content/i ) { return -1 }
            else  { $a cmp $b }
        }
        keys( %params_as_hash )
    ) {
    my $key = lc($k);
    $key =~ s/^\-//;
    if (exists $pos{$key}) {
        $result[$pos{$key}] = $params_as_hash{$k};
    } else {
        $leftover{$key} = $params_as_hash{$k};
    }
    }

    return \@result, \%leftover;
}

sub make_attributes {
    my $attr = shift;
    return () unless $attr && ref($attr) && ref($attr) eq 'HASH';
    my $escape =  shift || 0;
    my $do_not_quote = shift;

    my $quote = $do_not_quote ? '' : '"';

    my @attr_keys= sort keys %$attr;
    my(@att);
    foreach (@attr_keys) {
    my($key) = $_;
    $key=~s/^\-//;     # get rid of initial - if present

    # old way: breaks EBCDIC!
    # $key=~tr/A-Z_/a-z-/; # parameters are lower case, use dashes

    ($key="\L$key") =~ tr/_/-/; # parameters are lower case, use dashes

    my $value = $escape ? simple_escape($attr->{$_}) : $attr->{$_};
    push(@att,defined($attr->{$_}) ? qq/$key=$quote$value$quote/ : qq/$key/);
    }
    return sort @att;
}

sub simple_escape {
  return unless defined(my $toencode = shift);
  $toencode =~ s{&}{&amp;}gso;
  $toencode =~ s{<}{&lt;}gso;
  $toencode =~ s{>}{&gt;}gso;
  $toencode =~ s{\"}{&quot;}gso;
# Doesn't work.  Can't work.  forget it.
#  $toencode =~ s{\x8b}{&#139;}gso;
#  $toencode =~ s{\x9b}{&#155;}gso;
  $toencode;
}

sub utf8_chr {
    my $c = shift(@_);
    my $u = chr($c);
    utf8::encode($u); # drop utf8 flag
    return $u;
}

# unescape URL-encoded data
sub unescape {
  shift() if @_ > 0 and (ref($_[0]) || (defined $_[1] && $_[0] eq $CGI::DefaultClass));
  my $todecode = shift;
  return undef unless defined($todecode);
  $todecode =~ tr/+/ /;       # pluses become spaces
    if ($_EBCDIC) {
      $todecode =~ s/%([0-9a-fA-F]{2})/chr $A2E[hex($1)]/ge;
    } else {
    # handle surrogate pairs first -- dankogai. Ref: http://unicode.org/faq/utf_bom.html#utf16-2
    $todecode =~ s{
            %u([Dd][89a-bA-B][0-9a-fA-F]{2}) # hi
                %u([Dd][c-fC-F][0-9a-fA-F]{2})   # lo
              }{
              utf8_chr(
                   0x10000 
                   + (hex($1) - 0xD800) * 0x400 
                   + (hex($2) - 0xDC00)
                  )
              }gex;
      $todecode =~ s/%(?:([0-9a-fA-F]{2})|u([0-9a-fA-F]{4}))/
    defined($1)? chr hex($1) : utf8_chr(hex($2))/ge;
    }
  return $todecode;
}

# URL-encode data
#
# We cannot use the %u escapes, they were rejected by W3C, so the official
# way is %XX-escaped utf-8 encoding.
# Naturally, Unicode strings have to be converted to their utf-8 byte
# representation. 
# Byte strings were traditionally used directly as a sequence of octets.
# This worked if they actually represented binary data (i.e. in CGI::Compress).
# This also worked if these byte strings were actually utf-8 encoded; e.g.,
# when the source file used utf-8 without the appropriate "use utf8;".
# This fails if the byte string is actually a Latin 1 encoded string, but it
# was always so and cannot be fixed without breaking the binary data case.
# -- Stepan Kasal <skasal@redhat.com>
#

sub escape {
  # If we being called in an OO-context, discard the first argument.
  shift() if @_ > 1 and ( ref($_[0]) || (defined $_[1] && $_[0] eq $CGI::DefaultClass));
  my $toencode = shift;
  return undef unless defined($toencode);
  utf8::encode($toencode) if utf8::is_utf8($toencode);
    if ($_EBCDIC) {
      $toencode=~s/([^a-zA-Z0-9_.~-])/uc sprintf("%%%02x",$E2A[ord($1)])/eg;
    } else {
      $toencode=~s/([^a-zA-Z0-9_.~-])/uc sprintf("%%%02x",ord($1))/eg;
    }
  return $toencode;
}

# This internal routine creates date strings suitable for use in
# cookies and HTTP headers.  (They differ, unfortunately.)
# Thanks to Mark Fisher for this.
sub expires {
    my($time,$format) = @_;
    $format ||= 'http';

    my(@MON)=qw/Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec/;
    my(@WDAY) = qw/Sun Mon Tue Wed Thu Fri Sat/;

    # pass through preformatted dates for the sake of expire_calc()
    $time = expire_calc($time);
    return $time unless $time =~ /^\d+$/;

    # make HTTP/cookie date string from GMT'ed time
    # (cookies use '-' as date separator, HTTP uses ' ')
    my($sc) = ' ';
    $sc = '-' if $format eq "cookie";
    my($sec,$min,$hour,$mday,$mon,$year,$wday) = gmtime($time);
    $year += 1900;
    return sprintf("%s, %02d$sc%s$sc%04d %02d:%02d:%02d GMT",
                   $WDAY[$wday],$mday,$MON[$mon],$year,$hour,$min,$sec);
}

# This internal routine creates an expires time exactly some number of
# hours from the current time.  It incorporates modifications from 
# Mark Fisher.
sub expire_calc {
    my($time) = @_;
    my(%mult) = ('s'=>1,
                 'm'=>60,
                 'h'=>60*60,
                 'd'=>60*60*24,
                 'M'=>60*60*24*30,
                 'y'=>60*60*24*365);
    # format for time can be in any of the forms...
    # "now" -- expire immediately
    # "+180s" -- in 180 seconds
    # "+2m" -- in 2 minutes
    # "+12h" -- in 12 hours
    # "+1d"  -- in 1 day
    # "+3M"  -- in 3 months
    # "+2y"  -- in 2 years
    # "-3m"  -- 3 minutes ago(!)
    # If you don't supply one of these forms, we assume you are
    # specifying the date yourself
    my($offset);
    if (!$time || (lc($time) eq 'now')) {
      $offset = 0;
    } elsif ($time=~/^\d+/) {
      return $time;
    } elsif ($time=~/^([+-]?(?:\d+|\d*\.\d*))([smhdMy])/) {
      $offset = ($mult{$2} || 1)*$1;
    } else {
      return $time;
    }
    my $cur_time = time; 
    return ($cur_time+$offset);
}

sub ebcdic2ascii {
  my $data = shift;
  $data =~ s/(.)/chr $E2A[ord($1)]/ge;
  $data;
}

sub ascii2ebcdic {
  my $data = shift;
  $data =~ s/(.)/chr $A2E[ord($1)]/ge;
  $data;
}

1;

__END__

=head1 NAME

CGI::Util - Internal utilities used by CGI module

=head1 SYNOPSIS

none

=head1 DESCRIPTION

no public subroutines

=head1 AUTHOR INFORMATION

The CGI.pm distribution is copyright 1995-2007, Lincoln D. Stein. It is
distributed under the Artistic License 2.0. It is currently
maintained by Lee Johnson with help from many contributors.

Address bug reports and comments to: https://github.com/leejo/CGI.pm/issues

The original bug tracker can be found at: https://rt.cpan.org/Public/Dist/Display.html?Queue=CGI.pm

When sending bug reports, please provide the version of CGI.pm, the version of
Perl, the name and version of your Web server, and the name and version of the
operating system you are using.  If the problem is even remotely browser
dependent, please provide information about the affected browsers as well.

=head1 SEE ALSO

L<CGI>

=cut
