#!/usr/bin/env perl

# http://creation.mb.softbank.jp/web/web_pic_01.html

use strict;
use warnings;

use CGI;

my $q = new CGI;

my $text = $q->param('text');
my $artpack = $q->param('artpack') || 'softbank';

my %artpacks = (
  'softbank' => '/images/emoji/softbank/%04X.gif',
  'iphone'   => '/images/emoji/iphone/%04X.png',
);

# map the range character to the codepoint range
my %map = (
  'G' => 0xE0,
  'E' => 0xE1,
  'F' => 0xE2,
  'O' => 0xE3,
  'P' => 0xE4,
  'Q' => 0xE5
);

# converts an emoji webcode into its codepoint
# expects a single arg in the <range><char> format ex) G] or F'
sub WebcodeToCodepoint {
  # A:  Brings in one char directly as a string
  # C*: Brings in a char and converts it to its codepoint
  my ($set, $index) = unpack("AC*", $_[0]);

  # Find the first byte for this named codepoint
  my $prefix = $map{$set};

  # The chars are offset by 32, so undo that
  my $item = $index - 32;

  my $codepoint = $prefix << 8 | $item;

  return $codepoint;
}

sub CodepointToImage {
  return sprintf "<img src='" . $artpacks{$artpack} . "' />", $_[0];
}

sub DecimalToImage {
  my $dec = $_[0];
  my $range = $dec >> 8;

  if (0xE0 <= $range && $range <= 0xE5) {
    return CodepointToImage($1);
  }
  else {
    return "&#$dec;";
  }
}

$text =~ s/\$([GEFOPQ].)/CodepointToImage(WebcodeToCodepoint($1))/eg;
$text =~ s/&#([0-9]{5});/DecimalToImage($1)/eg;
$text =~ s/[\r\n]/<br \/>/g;

print "Content-Type: text/html; charset=utf8\n\n";
print $text;