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package RT::Config;

use strict;
use warnings;

use File::Spec ();

=head1 NAME

    RT::Config - RT's config

=head1 SYNOPSYS

    # get config object
    use RT::Config;
    my $config = new RT::Config;
    $config->LoadConfigs;

    # get or set option
    my $rt_web_path = $config->Get('WebPath');
    $config->Set(EmailOutputEncoding => 'latin1');

    # get config object from RT package
    use RT;
    RT->LoadConfig;
    my $config = RT->Config;

=head1 DESCRIPTION

C<RT::Config> class provide access to RT's and RT extensions' config files.

RT uses two files for site configuring:

First file is F<RT_Config.pm> - core config file. This file is shipped
with RT distribution and contains default values for all available options.
B<You should never edit this file.>

Second file is F<RT_SiteConfig.pm> - site config file. You can use it
to customize your RT instance. In this file you can override any option
listed in core config file.

RT extensions could also provide thier config files. Extensions should
use F<< <NAME>_Config.pm >> and F<< <NAME>_SiteConfig.pm >> names for
config files, where <NAME> is extension name.

B<NOTE>: All options from RT's config and extensions' configs are saved
in one place and thus extension could override RT's options, but it is not
recommended.

=cut

=head2 %META

Hash of Config options that may be user overridable
or may require more logic than should live in RT_*Config.pm

Keyed by config name, there are several properties that
can be set for each config optin:

 Section     - What header this option should be grouped
               under on the user Settings page
 Overridable - Can users change this option
 SortOrder   - Within a Section, how should the options be sorted
               for display to the user
 Widget      - Mason component path to widget that should be used 
               to display this config option
 WidgetArguments - An argument hash passed to the WIdget
    Description - Friendly description to show the user
    Values      - Arrayref of options (for select Widget)
    ValuesLabel - Hashref, key is the Value from the Values
                  list, value is a user friendly description
                  of the value
    Callback    - subref that receives no arguments.  It returns
                  a hashref of items that are added to the rest
                  of the WidgetArguments
 PostLoadCheck - subref passed the RT::Config object and the current
                 setting of the config option.  Can make further checks
                 (such as seeing if a library is installed) and then change
                 the setting of this or other options in the Config using 
                 the RT::Config option.

=cut

our %META = (
    # General user overridable options
    DefaultQueue => {
        Section         => 'General',
        Overridable     => 1,
        SortOrder       => 1,
        Widget          => '/Widgets/Form/Select',
        WidgetArguments => {
            Description => 'Default queue',    #loc
            Callback    => sub {
                my $ret = { Values => [], ValuesLabel => {}};
                my $q = new RT::Queues($HTML::Mason::Commands::session{'CurrentUser'});
                $q->UnLimit;
                while (my $queue = $q->Next) {
                    next unless $queue->CurrentUserHasRight("CreateTicket");
                    push @{$ret->{Values}}, $queue->Id;
                    $ret->{ValuesLabel}{$queue->Id} = $queue->Name;
                }
                return $ret;
            },
        }
    },
    UsernameFormat => {
        Section         => 'General',
        Overridable     => 1,
        SortOrder       => 2,
        Widget          => '/Widgets/Form/Select',
        WidgetArguments => {
            Description => 'Username format', # loc
            Values      => [qw(concise verbose)],
            ValuesLabel => {
                concise => 'Short usernames', # loc_left_pair
                verbose => 'Name and email address', # loc_left_pair
            },
        },
    },
    WebDefaultStylesheet => {
        Section         => 'General',                #loc
        Overridable     => 1,
        SortOrder       => 3,
        Widget          => '/Widgets/Form/Select',
        WidgetArguments => {
            Description => 'Theme',                  #loc
            # XXX: we need support for 'get values callback'
            Values => [qw(3.5-default 3.4-compat web2)],
        },
    },
    MessageBoxRichText => {
        Section => 'General',
        Overridable => 1,
        SortOrder => 4,
        Widget => '/Widgets/Form/Boolean',
        WidgetArguments => {
            Description => 'WYSIWYG message composer' # loc
        }
    },
    MessageBoxRichTextHeight => {
        Section => 'General',
        Overridable => 1,
        SortOrder => 5,
        Widget => '/Widgets/Form/Integer',
        WidgetArguments => {
            Description => 'WYSIWYG composer height', # loc
        }
    },
    MessageBoxWidth => {
        Section         => 'General',
        Overridable     => 1,
        SortOrder       => 6,
        Widget          => '/Widgets/Form/Integer',
        WidgetArguments => {
            Description => 'Message box width',           #loc
        },
    },
    MessageBoxHeight => {
        Section         => 'General',
        Overridable     => 1,
        SortOrder       => 7,
        Widget          => '/Widgets/Form/Integer',
        WidgetArguments => {
            Description => 'Message box height',          #loc
        },
    },
    SearchResultsRefreshInterval => {
        Section         => 'General',                       #loc
        Overridable     => 1,
        SortOrder       => 8,
        Widget          => '/Widgets/Form/Select',
        WidgetArguments => {
            Description => 'Search results refresh interval',                            #loc
            Values      => [qw(0 120 300 600 1200 3600 7200)],
            ValuesLabel => {
                0 => "Don't refresh search results.",                      #loc
                120 => "Refresh search results every 2 minutes.",          #loc
                300 => "Refresh search results every 5 minutes.",          #loc
                600 => "Refresh search results every 10 minutes.",         #loc
                1200 => "Refresh search results every 20 minutes.",        #loc
                3600 => "Refresh search results every 60 minutes.",        #loc
                7200 => "Refresh search results every 120 minutes.",       #loc
            },  
        },  
    },
    ResolveDefaultUpdateType => {
        Section         => 'General',                                      #loc
        Overridable     => 1,
        SortOrder       => 9,
        Widget          => '/Widgets/Form/Select',
        WidgetArguments => {
            Description => 'Default Update Type when Resolving',           #loc
            Values      => [qw(Comment Respond)],
            ValuesLabel => {
                Comment => "Comments (Not sent to requestors)",            #loc
                Respond => "Reply to requestors",                          #loc
            },
        },
    },
    SuppressAutoOpenOnUpdate => {
        Section => 'General',
        Overridable => 1,
        SortOrder => 10,
        Widget => '/Widgets/Form/Boolean',
        WidgetArguments => {
            Description => 'Suppress automatic new to open status change on ticket update' # loc
        }
    },

    # User overridable options for RT at a glance
    DefaultSummaryRows => {
        Section         => 'RT at a glance',    #loc
        Overridable     => 1,
        SortOrder       => 1,
        Widget          => '/Widgets/Form/Integer',
        WidgetArguments => {
            Description => 'Number of search results',    #loc
        },
    },
    HomePageRefreshInterval => {
        Section         => 'RT at a glance',                       #loc
        Overridable     => 1,
        SortOrder       => 2,
        Widget          => '/Widgets/Form/Select',
        WidgetArguments => {
            Description => 'Home page refresh interval',                #loc
            Values      => [qw(0 120 300 600 1200 3600 7200)],
            ValuesLabel => {
                0 => "Don't refresh home page.",                  #loc
                120 => "Refresh home page every 2 minutes.",      #loc
                300 => "Refresh home page every 5 minutes.",      #loc
                600 => "Refresh home page every 10 minutes.",     #loc
                1200 => "Refresh home page every 20 minutes.",    #loc
                3600 => "Refresh home page every 60 minutes.",    #loc
                7200 => "Refresh home page every 120 minutes.",   #loc
            },  
        },  
    },

    # User overridable options for Ticket displays
    MaxInlineBody => {
        Section         => 'Ticket display',              #loc
        Overridable     => 1,
        SortOrder       => 1,
        Widget          => '/Widgets/Form/Integer',
        WidgetArguments => {
            Description => 'Maximum inline message length',    #loc
            Hints =>
            "Length in characters; Use '0' to show all messages inline, regardless of length" #loc
        },
    },
    OldestTransactionsFirst => {
        Section         => 'Ticket display',
        Overridable     => 1,
        SortOrder       => 2,
        Widget          => '/Widgets/Form/Boolean',
        WidgetArguments => {
            Description => 'Show oldest history first',    #loc
        },
    },
    ShowUnreadMessageNotifications => { 
        Section         => 'Ticket display',
        Overridable     => 1,
        SortOrder       => 3,
        Widget          => '/Widgets/Form/Boolean',
        WidgetArguments => {
            Description => 'Notify me of unread messages',    #loc
        },

    },
    PlainTextPre => {
        Section         => 'Ticket display',
        Overridable     => 1,
        SortOrder       => 4,
        Widget          => '/Widgets/Form/Boolean',
        WidgetArguments => {
            Description => 'add <pre> tag around plain text attachments', #loc
            Hints       => "Use this to protect the format of plain text" #loc
        },
    },
    PlainTextMono => {
        Section         => 'Ticket display',
        Overridable     => 1,
        SortOrder       => 5,
        Widget          => '/Widgets/Form/Boolean',
        WidgetArguments => {
            Description => 'display wrapped and formatted plain text attachments', #loc
            Hints => 'Use css rules to display text monospaced and with formatting preserved, but wrap as needed.  This does not work well with IE6 and you should use the previous option', #loc
        },
    },

    # User overridable locale options
    DateTimeFormat => {
        Section         => 'Locale',                       #loc
        Overridable     => 1,
        Widget          => '/Widgets/Form/Select',
        WidgetArguments => {
            Description => 'Date format',                            #loc
            Callback => sub { my $ret = { Values => [], ValuesLabel => {}};
                              my $date = new RT::Date($HTML::Mason::Commands::session{'CurrentUser'});
                              $date->Set;
                              foreach my $value ($date->Formatters) {
                                 push @{$ret->{Values}}, $value;
                                 $ret->{ValuesLabel}{$value} = $date->$value();
                              }
                              return $ret;
            },
        },
    },

    RTAddressRegexp => {
        Type    => 'SCALAR',
        PostLoadCheck => sub {
            my $self = shift;
            my $value = $self->Get('RTAddressRegexp');
            return if $value;

            $RT::Logger->debug(
                'The RTAddressRegexp option is not set in the config.'
                .' Not setting this option results in additional SQL queries to'
                .' check whether each address belongs to RT or not.'
                .' It is especially important to set this option if RT recieves'
                .' emails on addresses that are not in the database or config.'
            );
        },
    },
    # User overridable mail options
    EmailFrequency => {
        Section         => 'Mail',                                     #loc
        Overridable     => 1,
        Default     => 'Individual messages',
        Widget          => '/Widgets/Form/Select',
        WidgetArguments => {
            Description => 'Email delivery',    #loc
            Values      => [
            'Individual messages',    #loc
            'Daily digest',           #loc
            'Weekly digest',          #loc
            'Suspended'               #loc
            ]
        }
    },
    NotifyActor => {
        Section         => 'Mail',                                     #loc
        Overridable     => 1,
        SortOrder       => 2,
        Widget          => '/Widgets/Form/Boolean',
        WidgetArguments => {
            Description => 'Outgoing mail', #loc
            Hints => 'Should RT send you mail for ticket updates you make?', #loc
        }
    },

    # this tends to break extensions that stash links in ticket update pages
    Organization => {
        Type            => 'SCALAR',
        PostLoadCheck   => sub {
            my ($self,$value) = @_;
            $RT::Logger->error("your \$Organization setting ($value) appears to contain whitespace.  Please fix this.")
                if $value =~ /\s/;;
        },
    },

    # Internal config options
    DisableGraphViz => {
        Type            => 'SCALAR',
        PostLoadCheck   => sub {
            my $self  = shift;
            my $value = shift;
            return if $value;
            return if $INC{'GraphViz.pm'};
            local $@;
            return if eval {require GraphViz; 1};
            $RT::Logger->debug("You've enabled GraphViz, but we couldn't load the module: $@");
            $self->Set( DisableGraphViz => 1 );
        },
    },
    DisableGD => {
        Type            => 'SCALAR',
        PostLoadCheck   => sub {
            my $self  = shift;
            my $value = shift;
            return if $value;
            return if $INC{'GD.pm'};
            local $@;
            return if eval {require GD; 1};
            $RT::Logger->debug("You've enabled GD, but we couldn't load the module: $@");
            $self->Set( DisableGD => 1 );
        },
    },
    MailPlugins  => { Type => 'ARRAY' },
    Plugins      => { Type => 'ARRAY' },
    GnuPG        => { Type => 'HASH' },
    GnuPGOptions => { Type => 'HASH',
        PostLoadCheck => sub {
            my $self = shift;
            my $gpg = $self->Get('GnuPG');
            return unless $gpg->{'Enable'};
            my $gpgopts = $self->Get('GnuPGOptions');
            unless (-d $gpgopts->{homedir}  && -r _ ) { # no homedir, no gpg
                $RT::Logger->debug(
                    "RT's GnuPG libraries couldn't successfully read your".
                    " configured GnuPG home directory (".$gpgopts->{homedir}
                    ."). PGP support has been disabled");
                $gpg->{'Enable'} = 0;
                return;
            }


            require RT::Crypt::GnuPG;
            unless (RT::Crypt::GnuPG->Probe()) {
                $RT::Logger->debug(
                    "RT's GnuPG libraries couldn't successfully execute gpg.".
                    " PGP support has been disabled");
                $gpg->{'Enable'} = 0;
            }
        }
    },
);
my %OPTIONS = ();

=head1 METHODS

=head2 new

Object constructor returns new object. Takes no arguments.

=cut

sub new {
    my $proto = shift;
    my $class = ref($proto) ? ref($proto) : $proto;
    my $self  = bless {}, $class;
    $self->_Init(@_);
    return $self;
}

sub _Init {
    return;
}

=head2 InitConfig

Do nothin right now.

=cut

sub InitConfig {
    my $self = shift;
    my %args = ( File => '', @_ );
    $args{'File'} =~ s/(?<=Config)(?=\.pm$)/Meta/;
    return 1;
}

=head2 LoadConfigs

Load all configs. First of all load RT's config then load
extensions' config files in alphabetical order.
Takes no arguments.

=cut

sub LoadConfigs {
    my $self    = shift;

    $self->InitConfig( File => 'RT_Config.pm' );
    $self->LoadConfig( File => 'RT_Config.pm' );

    my @configs = $self->Configs;
    $self->InitConfig( File => $_ ) foreach @configs;
    $self->LoadConfig( File => $_ ) foreach @configs;
    return;
}

=head1 LoadConfig

Takes param hash with C<File> field.
First, the site configuration file is loaded, in order to establish
overall site settings like hostname and name of RT instance.
Then, the core configuration file is loaded to set fallback values
for all settings; it bases some values on settings from the site
configuration file.

B<Note> that core config file don't change options if site config
has set them so to add value to some option instead of
overriding you have to copy original value from core config file.

=cut

sub LoadConfig {
    my $self = shift;
    my %args = ( File => '', @_ );
    $args{'File'} =~ s/(?<!Site)(?=Config\.pm$)/Site/;
    if ( $args{'File'} eq 'RT_SiteConfig.pm'
        and my $site_config = $ENV{RT_SITE_CONFIG} )
    {
        $self->_LoadConfig( %args, File => $site_config );
    } else {
        $self->_LoadConfig(%args);
    }
    $args{'File'} =~ s/Site(?=Config\.pm$)//;
    $self->_LoadConfig(%args);
    return 1;
}

sub _LoadConfig {
    my $self = shift;
    my %args = ( File => '', @_ );

    my ($is_ext, $is_site);
    if ( $args{'File'} eq ($ENV{RT_SITE_CONFIG}||'') ) {
        ($is_ext, $is_site) = ('', 1);
    } else {
        $is_ext = $args{'File'} =~ /^(?!RT_)(?:(.*)_)(?:Site)?Config/ ? $1 : '';
        $is_site = $args{'File'} =~ /SiteConfig/ ? 1 : 0;
    }

    eval {
        package RT;
        local *Set = sub(\[$@%]@) {
            my ( $opt_ref, @args ) = @_;
            my ( $pack, $file, $line ) = caller;
            return $self->SetFromConfig(
                Option     => $opt_ref,
                Value      => [@args],
                Package    => $pack,
                File       => $file,
                Line       => $line,
                SiteConfig => $is_site,
                Extension  => $is_ext,
            );
        };
        my @etc_dirs = ($RT::LocalEtcPath);
        push @etc_dirs, RT->PluginDirs('etc') if $is_ext;
        push @etc_dirs, $RT::EtcPath, @INC;
        local @INC = @etc_dirs;
        require $args{'File'};
    };
    if ($@) {
        return 1 if $is_site && $@ =~ qr{^Can't locate \Q$args{File}};
        if ( $is_site || $@ !~ qr{^Can't locate \Q$args{File}} ) {
            die qq{Couldn't load RT config file $args{'File'}:\n\n$@};
        }

        my $username = getpwuid($>);
        my $group    = getgrgid($();

        my ( $file_path, $fileuid, $filegid );
        foreach ( $RT::LocalEtcPath, $RT::EtcPath, @INC ) {
            my $tmp = File::Spec->catfile( $_, $args{File} );
            ( $fileuid, $filegid ) = ( stat($tmp) )[ 4, 5 ];
            if ( defined $fileuid ) {
                $file_path = $tmp;
                last;
            }
        }
        unless ($file_path) {
            die
                qq{Couldn't load RT config file $args{'File'} as user $username / group $group.\n}
                . qq{The file couldn't be found in $RT::LocalEtcPath and $RT::EtcPath.\n$@};
        }

        my $message = <<EOF;

RT couldn't load RT config file %s as:
    user: $username 
    group: $group

The file is owned by user %s and group %s.  

This usually means that the user/group your webserver is running
as cannot read the file.  Be careful not to make the permissions
on this file too liberal, because it contains database passwords.
You may need to put the webserver user in the appropriate group
(%s) or change permissions be able to run succesfully.
EOF

        my $fileusername = getpwuid($fileuid);
        my $filegroup    = getgrgid($filegid);
        my $errormessage = sprintf( $message,
            $file_path, $fileusername, $filegroup, $filegroup );
        die "$errormessage\n$@";
    }
    return 1;
}

sub PostLoadCheck {
    my $self = shift;
    foreach my $o ( grep $META{$_}{'PostLoadCheck'}, $self->Options( Overridable => undef ) ) {
        $META{$o}->{'PostLoadCheck'}->( $self, $self->Get($o) );
    }
}

=head2 Configs

Returns list of config files found in local etc, plugins' etc
and main etc directories.

=cut

sub Configs {
    my $self    = shift;

    my @configs = ();
    foreach my $path ( $RT::LocalEtcPath, RT->PluginDirs('etc'), $RT::EtcPath ) {
        my $mask = File::Spec->catfile( $path, "*_Config.pm" );
        my @files = glob $mask;
        @files = grep !/^RT_Config\.pm$/,
            grep $_ && /^\w+_Config\.pm$/,
            map { s/^.*[\\\/]//; $_ } @files;
        push @configs, sort @files;
    }

    my %seen;
    @configs = grep !$seen{$_}++, @configs;
    return @configs;
}

=head2 Get

Takes name of the option as argument and returns its current value.

In the case of a user-overridable option, first checks the user's
preferences before looking for site-wide configuration.

Returns values from RT_SiteConfig, RT_Config and then the %META hash
of configuration variables's "Default" for this config variable,
in that order.

Returns different things in scalar and array contexts. For scalar
options it's not that important, however for arrays and hash it's.
In scalar context returns references to arrays and hashes.

Use C<scalar> perl's op to force context, especially when you use
C<(..., Argument => RT->Config->Get('ArrayOpt'), ...)>
as perl's '=>' op doesn't change context of the right hand argument to
scalar. Instead use C<(..., Argument => scalar RT->Config->Get('ArrayOpt'), ...)>.

It's also important for options that have no default value(no default
in F<etc/RT_Config.pm>). If you don't force scalar context then you'll
get empty list and all your named args will be messed up. For example
C<(arg1 => 1, arg2 => RT->Config->Get('OptionDoesNotExist'), arg3 => 3)>
will result in C<(arg1 => 1, arg2 => 'arg3', 3)> what is most probably
unexpected, or C<(arg1 => 1, arg2 => RT->Config->Get('ArrayOption'), arg3 => 3)>
will result in C<(arg1 => 1, arg2 => 'element of option', 'another_one' => ..., 'arg3', 3)>.

=cut

sub Get {
    my ( $self, $name, $user ) = @_;

    my $res;
    if ( $user && $user->id && $META{$name}->{'Overridable'} ) {
        $user = $user->UserObj if $user->isa('RT::CurrentUser');
        my $prefs = $user->Preferences($RT::System);
        $res = $prefs->{$name} if $prefs;
    }
    $res = $OPTIONS{$name}           unless defined $res;
    $res = $META{$name}->{'Default'} unless defined $res;
    return $self->_ReturnValue( $res, $META{$name}->{'Type'} || 'SCALAR' );
}

=head2 Set

Set option's value to new value. Takes name of the option and new value.
Returns old value.

The new value should be scalar, array or hash depending on type of the option.
If the option is not defined in meta or the default RT config then it is of
scalar type.

=cut

sub Set {
    my ( $self, $name ) = ( shift, shift );

    my $old = $OPTIONS{$name};
    my $type = $META{$name}->{'Type'} || 'SCALAR';
    if ( $type eq 'ARRAY' ) {
        $OPTIONS{$name} = [@_];
        { no warnings 'once'; no strict 'refs'; @{"RT::$name"} = (@_); }
    } elsif ( $type eq 'HASH' ) {
        $OPTIONS{$name} = {@_};
        { no warnings 'once'; no strict 'refs'; %{"RT::$name"} = (@_); }
    } else {
        $OPTIONS{$name} = shift;
        {no warnings 'once'; no strict 'refs'; ${"RT::$name"} = $OPTIONS{$name}; }
    }
    $META{$name}->{'Type'} = $type;
    return $self->_ReturnValue( $old, $type );
}

sub _ReturnValue {
    my ( $self, $res, $type ) = @_;
    return $res unless wantarray;

    if ( $type eq 'ARRAY' ) {
        return @{ $res || [] };
    } elsif ( $type eq 'HASH' ) {
        return %{ $res || {} };
    }
    return $res;
}

sub SetFromConfig {
    my $self = shift;
    my %args = (
        Option     => undef,
        Value      => [],
        Package    => 'RT',
        File       => '',
        Line       => 0,
        SiteConfig => 1,
        Extension  => 0,
        @_
    );

    unless ( $args{'File'} ) {
        ( $args{'Package'}, $args{'File'}, $args{'Line'} ) = caller(1);
    }

    my $opt = $args{'Option'};

    my $type;
    my $name = $self->__GetNameByRef($opt);
    if ($name) {
        $type = ref $opt;
        $name =~ s/.*:://;
    } else {
        $name = $$opt;
        $type = $META{$name}->{'Type'} || 'SCALAR';
    }

    # if option is already set we have to check where
    # it comes from and may be ignore it
    if ( exists $OPTIONS{$name} ) {
        if ( $args{'SiteConfig'} && $args{'Extension'} ) {
            # if it's site config of an extension then it can only
            # override options that came from its main config
            if ( $args{'Extension'} ne $META{$name}->{'Source'}{'Extension'} ) {
                my %source = %{ $META{$name}->{'Source'} };
                warn
                    "Change of config option '$name' at $args{'File'} line $args{'Line'} has been ignored."
                    ." This option earlier has been set in $source{'File'} line $source{'Line'}."
                    ." To overide this option use ". ($source{'Extension'}||'RT')
                    ." site config."
                ;
                return 1;
            }
        } elsif ( !$args{'SiteConfig'} && $META{$name}->{'Source'}{'SiteConfig'} ) {
            # if it's core config then we can override any option that came from another
            # core config, but not site config

            my %source = %{ $META{$name}->{'Source'} };
            if ( $source{'Extension'} ne $args{'Extension'} ) {
                # as a site config is loaded earlier then its base config
                # then we warn only on different extensions, for example
                # RTIR's options is set in main site config or RTFM's
                warn
                    "Change of config option '$name' at $args{'File'} line $args{'Line'} has been ignored."
                    ." It may be ok, but we want you to be aware."
                    ." This option has been set earlier in $source{'File'} line $source{'Line'}."
                ;
            }

            return 1;
        }
    }

    $META{$name}->{'Type'} = $type;
    foreach (qw(Package File Line SiteConfig Extension)) {
        $META{$name}->{'Source'}->{$_} = $args{$_};
    }
    $self->Set( $name, @{ $args{'Value'} } );

    return 1;
}

{
    my $last_pack = '';

    sub __GetNameByRef {
        my $self = shift;
        my $ref  = shift;
        my $pack = shift;
        if ( !$pack && $last_pack ) {
            my $tmp = $self->__GetNameByRef( $ref, $last_pack );
            return $tmp if $tmp;
        }
        $pack ||= 'main::';
        $pack .= '::' unless substr( $pack, -2 ) eq '::';

        my %ref_sym = (
            SCALAR => '$',
            ARRAY  => '@',
            HASH   => '%',
            CODE   => '&',
        );
        no strict 'refs';
        my $name = undef;

        # scan $pack's nametable(hash)
        foreach my $k ( keys %{$pack} ) {

            # hash for main:: has reference on itself
            next if $k eq 'main::';

            # if entry has trailing '::' then
            # it is link to other name space
            if ( $k =~ /::$/ ) {
                $name = $self->__GetNameByRef( $ref, $k );
                return $name if $name;
            }

            # entry of the table with references to
            # SCALAR, ARRAY... and other types with
            # the same name
            my $entry = ${$pack}{$k};
            next unless $entry;

            # get entry for type we are looking for
            # XXX skip references to scalars or other references.
            # Otherwie 5.10 goes boom. maybe we should skip any
            # reference
            next if ref($entry) eq 'SCALAR' || ref($entry) eq 'REF';
            my $entry_ref = *{$entry}{ ref($ref) };
            next unless $entry_ref;

            # if references are equal then we've found
            if ( $entry_ref == $ref ) {
                $last_pack = $pack;
                return ( $ref_sym{ ref($ref) } || '*' ) . $pack . $k;
            }
        }
        return '';
    }
}

=head2 Metadata


=head2 Meta

=cut

sub Meta {
    return $META{ $_[1] };
}

sub Sections {
    my $self = shift;
    my %seen;
    my @sections = sort
        grep !$seen{$_}++,
        map $_->{'Section'} || 'General',
        values %META;
    return @sections;
}

sub Options {
    my $self = shift;
    my %args = ( Section => undef, Overridable => 1, Sorted => 1, @_ );
    my @res  = keys %META;
    
    @res = grep( ( $META{$_}->{'Section'} || 'General' ) eq $args{'Section'},
        @res 
    ) if defined $args{'Section'};

    if ( defined $args{'Overridable'} ) {
        @res
            = grep( ( $META{$_}->{'Overridable'} || 0 ) == $args{'Overridable'},
            @res );
    }

    if ( $args{'Sorted'} ) {
        @res = sort {
            ($META{$a}->{SortOrder}||9999) <=> ($META{$b}->{SortOrder}||9999)
            || $a cmp $b 
        } @res;
    } else {
        @res = sort { $a cmp $b } @res;
    }
    return @res;
}

RT::Base->_ImportOverlays();

1;
