package Plack::Middleware::IIS6ScriptNameFix;

use strict;
use parent 'Plack::Middleware';

sub call {
    my($self, $env) = @_;

    if ($env->{SERVER_SOFTWARE} && $env->{SERVER_SOFTWARE} =~ /IIS\/[6-9]\.[0-9]/) {
        my @script_name = split(m!/!, $env->{PATH_INFO});
        my @path_translated = split(m!/|\\\\?!, $env->{PATH_TRANSLATED});
        my @path_info;

        while ($script_name[$#script_name] eq $path_translated[$#path_translated]) {
            pop(@path_translated);
            unshift(@path_info, pop(@script_name));
        }

        unshift(@path_info, '', '');

        $env->{PATH_INFO} = join('/', @path_info);
        $env->{SCRIPT_NAME} = join('/', @script_name);
    }

    return $self->app->($env);
}

1;

__END__

=head1 NAME

Plack::Middleware::IIS6ScriptNameFix - fixes wrong SCRIPT_NAME and PATH_INFO that IIS6 sets

=head1 SYNOPSIS

  # in your app.psgi
  use Plack::Builder;

  builder {
    enable "IIS6ScriptNameFix";
    $app;
  };

  # Or from the command line
  plackup -s FCGI -e 'enable "IIS6ScriptNameFix"' /path/to/app.psgi

=head1 DESCRIPTION

This middleware fixes wrong C<SCRIPT_NAME> and C<PATH_INFO> set by IIS6.

=head1 AUTHORS

Florian Ragwitz

=cut