#!/bin/false
package SVN::Web;

use strict;
use warnings;

use Encode ();
use URI::Escape;
use SVN::Client;
use SVN::Ra;
use YAML ();
use Template;
use File::Spec;
use Plack::Request;

use SVN::Web::X;
use FindBin;

use SVN::Web::I18N;

# Add the localisations that ship with SVN::Web as the default, and set
# the default language.  This will be overridden later, but ensures that
# any error messages generated *before* it's overridden are generated
# properly.
SVN::Web::I18N::add_directory(
    File::Spec->catdir( substr( __FILE__, 0, -3 ), 'I18N' ) );
SVN::Web::I18N::loc_lang('en');

our $VERSION = 0.63;

my $template;
my $config;

my %REPOS;

sub load_config {
    return if defined $config;
    my $file = shift || 'config.yaml';
    my $config = YAML::LoadFile($file);
    set_config($config);
}

sub canonicalise_config {

    # Catch missing / incorrect 'version' entries
    die "Config file does not define a 'version' key."
      unless exists $config->{version} and defined $config->{version};

    die
"Configuration file version ($config->{version}) does not match SVN::Web version ($VERSION)"
      if $config->{version} != $VERSION;

    # Deal with possibly conflicting 'templatedir' and 'templatedirs' settings.

    # If neither of them are set, use 'templatedirs'
    if ( !exists $config->{templatedir} and !exists $config->{templatedirs} ) {
        $config->{templatedirs} = [ File::Spec->catdir(qw(template trac)) ];
    }

    # If 'templatedir' is the only one set, use it.
    if ( exists $config->{templatedir} and !exists $config->{templatedirs} ) {
        $config->{templatedirs} = [ $config->{templatedir} ];
        delete $config->{templatedir};
    }

    # If they're both set then throw an error
    if ( exists $config->{templatedir} and exists $config->{templatedirs} ) {
        die "templatedir and templatedirs both defined in config.yaml";
    }

    # Handle tt_compile_dir.  If it doesn't exist then set it to undef.
    # If it does exist, and is defined, append a '.' and the current
    # real UID, to help ensure uniqueness.
    unless ( exists $config->{tt_compile_dir} ) {
        $config->{tt_compile_dir} = undef;    # undef == no compiling
    }
    else {
        if ( defined $config->{tt_compile_dir} ) {
            $config->{tt_compile_dir} .= '.' . $<;
        }
    }

    # Handle timedate_format
    unless ( exists $config->{timedate_format} ) {
        $config->{timedate_format} = '%Y/%m/%d %H:%M:%S';
    }

    # Set the timezone, if not already specified.
    $config->{timezone} = '' unless exists $config->{timezone};

    # If cache/opts/directory_umask is configured, and it has a leading
    # 0 then ensure it's treated as an octal number.
    $config->{cache}{opts}{directory_umask} =
      oct( $config->{cache}{opts}{directory_umask} )
      if exists $config->{cache}{opts}{directory_umask}
          and $config->{cache}{opts}{directory_umask} =~ m/^0/;

    # Add any additional language directories
    if ( defined $config->{language_dirs} ) {
        for my $dir ( @{ $config->{language_dirs} } ) {
            SVN::Web::I18N::add_directory($dir);
        }
    }

    return;
}

sub set_config {
    $config = shift;

    canonicalise_config();
}

sub get_config {
    return $config;
}

my $repospool = SVN::Pool->new();

sub get_repos {
    my $repos = shift;

    SVN::Web::X->throw(
        error => '(unconfigured repository)',
        vars  => []
    ) unless exists $config->{repos}{$repos} || $config->{reposparent};

    my $repo_uri =
      $config->{reposparent}
      ? File::Spec->catdir( $config->{reposparent}, $repos )
      : $config->{repos}{$repos};

    SVN::Web::X->throw(
        error => '(no such repo %1 %2)',
        vars  => [ $repos, $repo_uri ]
      )
      unless defined $repos
          and ( exists $config->{repos}{$repos} or -e $repo_uri );

    $repo_uri =~ s{/$}{}g;    # Trim trailing '/', SVN::Repos::open fails
                              # otherwise

    # If there's a leading '/' then tack 'file://' on to the start
    $repo_uri = "file://$repo_uri" if $repo_uri =~ m{^/};

    # warn "REPO_URI: $repo_uri";

    eval {
        my $client = SVN::Client->new( pool => $repospool );
        my $auth = $client->auth;
        $REPOS{$repos}{uri} ||= $repo_uri;
        $REPOS{$repos}{ra}  ||= SVN::Ra->new(
            url  => $repo_uri,
            pool => $repospool,
            auth => $auth,
        );
    };

    if ($@) {
        my $e = $@;
        SVN::Web::X->throw(
            error => '(SVN::Client->new() failed: %1 %2)',
            vars  => [ $repo_uri, $e ]
        );
    }

    if ( $config->{block} ) {
        for my $blocked ( @{ $config->{block} } ) {
            delete $REPOS{$blocked};
        }
    }
}

sub get_action {
    my $cfg = shift;
    my $action_pkg;

    if ( exists $config->{actions}{ $cfg->{action} } ) {
        if ( ref( $config->{actions}{ $cfg->{action} } ) eq 'HASH' ) {
            if ( exists $config->{actions}{ $cfg->{action} }{class} ) {
                $action_pkg = $config->{actions}{ $cfg->{action} }{class};
            }
        }
    }

    unless ($action_pkg) {
        $action_pkg = $cfg->{action};
        $action_pkg =~ s{^(\w)}{\U$1};
        $action_pkg = __PACKAGE__ . "::$action_pkg";
    }

    eval "require $action_pkg && $action_pkg->can('run')"
      or SVN::Web::X->throw(
        error => '(missing package %1 for action %2: %3)',
        vars  => [ $action_pkg, $cfg->{action}, $@ ]
      );

    my $repos = $cfg->{repos} ? $REPOS{ $cfg->{repos} } : undef;

    return $action_pkg->new(
        %$cfg,
        reposname => $cfg->{repos},
        repos     => $repos,
        config    => $config
    );
}

sub run {
    my $cfg = shift;

    my $action;
    my $html;
    my $cache;

    if ( defined $config->{cache}{class} ) {
        eval "require $config->{cache}{class}"
          or SVN::Web::X->throw(
            error => '(require %1 failed: %2)',
            vars  => [ $config->{cache}{class}, $@ ]
          );

        $config->{cache}{opts} = {} unless exists $config->{cache}{opts};
        $config->{cache}{opts}{namespace} = $cfg->{repos};
        $cache = $config->{cache}{class}->new( $config->{cache}{opts} );
    }

    if ( defined $cfg->{repos} && length $cfg->{repos} ) {
        get_repos( $cfg->{repos} );
    }

    if ( $cfg->{repos} && $REPOS{ $cfg->{repos} } ) {
        @{ $cfg->{navpaths} } = File::Spec::Unix->splitdir( $cfg->{path} );
        shift @{ $cfg->{navpaths} };

        # should use attribute or things alike
        $action = get_action(
            {
                %$cfg,
                opts => exists $config->{actions}{ $cfg->{action} }{opts}
                ? $config->{actions}{ $cfg->{action} }{opts}
                : {},
            }
        );
    }
    else {
        $cfg->{action} = 'list';
        $action = get_action(
            {
                %$cfg,
                opts => exists $config->{actions}{ $cfg->{action} }{opts}
                ? $config->{actions}{ $cfg->{action} }{opts}
                : {},
            }
        );
    }

    # Determine the language to use
    my $lang =
      get_language( $cfg->{cgi}, $config->{languages},
        $config->{default_language} );

    $cfg->{lang} = $lang;    # Note the preference, stored in a cookie
                             # later

    SVN::Web::I18N::loc_lang($lang);    # Set the localisation language

    # Generate output, from the cache if necessary.

    # Does the action support caching?  If so, get the cache key
    my $cache_key;
    if ( defined $cache and $action->can('cache_key') ) {
        $cache_key =
          join( ':', $cfg->{action}, $lang ) . ':' . $action->cache_key();
    }

    # If there's a key, retrieve the data from the cache
    $html = $cache->get($cache_key) if defined $cache_key;

    # No data?  Get the action to generate it, then cache it
    unless ( defined $html ) {

        # Create a default pool for the action's allocation
        my $pool = SVN::Pool->new_default();

        $REPOS{ $cfg->{repos} }{client} = SVN::Client->new( config => {} );

        $html = $action->run();

        $pool->clear();

        if ( defined $cache_key ) {
            $cache->set( $cache_key, $html, $cfg->{cache}{expires_in} );
        }
    }

    return $html;
}

sub get_language {
    my $obj          = shift;    # Plack object
    my $languages    = shift;    # Hash ref of valid langauges
    my $default_lang = shift;    # Default language

    my $lang = $obj->param('lang');

    # If lang was included in the query string then delete it now we've
    # got it.  This stops it showing up in from calls to self_url().

    ## FIXME for Plack

    # If no valid lang=.. param was found then check the user's cookies

    unless ( defined $lang ) {
        $lang = $obj->cookies->{'svnweb-lang'};
    }

    # If $lang is not defined, or if it's not in the hash of valid languages
    # then use the default configured language, falling back to English as
    # a last resort.
    if ( !defined $lang or !exists $languages->{$lang} ) {
        $lang = $default_lang;
        $lang = 'en' unless defined $lang;
    }

    die "lang is not defined" unless defined $lang;

    return $lang;
}

sub psgi_output {
    my ( $req, $cfg, $html ) = @_;

    return unless defined $html;

    my $res = $req->new_response(200);
    $res->cookies->{ 'svnweb-lang' } = $cfg->{lang};


    if ( ref $html ) {

        if ( $html->{template} ) {
            my $body;
            $template->process(
                $html->{template},
                {
                    c => $cfg,
                    %{ $html->{data} }
                }, \$body
            ) or die "Template::process() error: " . $template->error;

            $res->content_type('text/html; charset=utf-8');
            $res->body(Encode::encode('utf8',$body));
        }
        else {
            $res->content_type($html->{mimetype} || 'text/plain');
            $res->body($html->{body});
        }
    }
    else {
        $res->content_type('text/plain');
        $res->body($html);
    }

    return $res->finalize

}

sub get_template {
    Template->new(
        {
            INCLUDE_PATH => $config->{templatedirs},
            COMPILE_DIR  => $config->{tt_compile_dir},
            PRE_CHOMP    => 2,
            POST_CHOMP   => 2,
            FILTERS      => {
                l => ( [ \&loc_filter, 1 ] ),
                anchor => ( [ \&anchor_filter, 1 ] ),
            },
            ENCODING     => 'utf8',
        }
    );
}

sub run_psgi {

    my $c = shift;
    my $env = shift;
    my $req = Plack::Request->new($env);

    $template ||= get_template();

    my ( $html, $cfg );

    $cfg = {
        style     => $config->{style},
        cgi       => $req,
        languages => $config->{languages},
    };

    eval {
        my ( $action, $base, $repo, $script, $path ) = crack_url($req);

        SVN::Web::X->throw(
            error => '(action %1 not supported)',
            vars  => [$action]
        ) unless exists $config->{actions}{ lc($action) };

        $cfg->{repos}    = $repo;
        $cfg->{action}   = $action;
        $cfg->{path}     = $path;
        $cfg->{script}   = $script;
        $cfg->{base_uri} = $base;
        $cfg->{self_uri} = $req->path();
        $cfg->{config}   = $config;

        $html = run($cfg);
    };

    if ( my $e = SVN::Web::X->caught() ) {
        $html->{template} = 'x';
        $html->{data}{error_msg} =
          SVN::Web::I18N::loc( $e->error(), @{ $e->vars() } );
    }
    else {
        if ($@) {
            $html->{template} = 'x';
            $html->{data}{error_msg} = $@;
        }
    }

    return psgi_output( $req, $cfg, $html );
}

sub loc_filter {
    my $context = shift;
    my @args    = @_;
    return sub { SVN::Web::I18N::loc( $_[0], @args ) };
}

sub anchor_filter {
    my $context = shift;
    return sub {
        my $str = shift;
        $str =~ s/[\/% ]/_/g;
        return $str;
    };
}

# Crack a URL and determine the components we need.
sub crack_url {

    my $obj = shift;

    my $path_info = Encode::decode('utf8',$obj->path);

    # warn "PATH_INFO: $path_info";

    my ( $action, $base, $repo, $script, $path );

    # Determine $repo.
    #
    # This is used as the key in to the hash of configured repositories.
    # It may be the empty string, in which case the action to run is
    # the 'list repositories' action.
    if ( $path_info eq '/' ) {
        $repo   = '';       # No repo, show repo list
        $action = 'list';
    }
    else {

        # Start with $repo equal to $filename.  Then remove $location.
        # This needs to be quoted for systems where the path may include
        # backslashes.  There may also be a trailing directory separator
        # which needs removing.
        #
        # XXX In an ideal world File::Spec would tell us what the directory
        # separator is.  For the time being, punt, and use both forward and
        # backward slashes.
        ($repo) = $path_info =~ m{^/([^/]+)/?};
        $repo = uri_unescape($repo);
    }

    #    warn "REPO: $repo";

    # Determine $action
    #
    # This will be used as the key in to the hash of configured actions
    # and their classes.  If no action is included in the URL then the
    # default action is 'browse'.
    unless ( defined $action ) {
            my @path = split( '/', $path_info );
            # warn "SPLIT PATH: ", join('|', @path);
            $action = $path[2] || 'browse';
    }

    #    warn "ACTION: $action";

    # Determine $path
    #
    # This is the path in the repository that we will be acting on.  Some
    # actions don't need this set.
    if ( $action eq 'list' ) {
        $path = '/';
    }
    else {
        if ( $path_info eq '/' ) {
            $path = '/';
        }
        else {
            $path = $path_info;
            $path =~ s{^/$repo(/$action)?}{};
            $path =~ s{/+$}{} unless $path eq '/';
        }
    }

    # Unescape it, as it will have been escaped on the web page
    $path = uri_unescape($path);

    #    warn "PATH: $path";

    # Determine $script
    #
    # $script is the URI that points to the SVN::Web script.  If this
    # is CGI then it's something like 'http://host//svnweb/index.cgi'.
    # If it's an Apache handler then it will be a directory reference,
    # like '/svnweb', or possibly '/'.

    $script = $obj->script_name;

    #    warn "SCRIPT: $script";

    # Determine $base
    #
    # $base is the URI that points to the directory that contains index.cgi,
    # config.yaml, css/, etc.  It's needed to generate links to the .css
    # files.

    # In all cases, $base is a substring of $script.  In the mod_perl and
    # svnweb-server cases it's identical
    # $base = $script;       # Only in mod_perl case
    $base = $obj->base;       # Only in mod_perl case

    $base =~ s{/$}{};    # Remove trailing slash

    #    warn "BASE: $base";

    return ( $action, $base, $repo, $script, $path );
}

1;

__END__

=head1 NAME

SVN::Web - Subversion repository web frontend

=head1 SYNOPSIS

If you are upgrading an existing SVN::Web installation then please see
L<UPDATING.pod>.  Installing new SVN::Web versions without making sure
the configuration file, templates, and localisations are properly updated
and merged will likely break your current installation.

To get started with SVN::Web.

=over

=item 1.

Create a directory for SVN::Web's configuration files, templates,
stylesheets, and other data.

  mkdir svnweb

=item 2.

Run C<svnweb-install> in this directory to configure the environment.

  cd svnweb
  svnweb-install

=item 3.

Edit the file F<config.yaml> that's been created, and add the following
two lines:

  repos:
    test: 'file:///path/to/repo'

C<file:///path/to/repo> should be the URL for an existing Subversion
repository.

=item 4.

Either configure your web server (see L</"WEB SERVERS">) to use SVN::Web,
or run with C<plackup> to start a simple web server for testing.

  plackup -Ilib/ ./SVN-Web.psgi

=item 5.

Point your web browser at the correct URL to browse your repository.
If you've run C<plackup> then this is L<http://localhost:5000/>.

=back

See L<https://github.com/djzort/SVN-Web> for the SVN::Web source code.

=head1 DESCRIPTION

SVN::Web provides a web interface to subversion repositories. It's
features include:

=over

=item *

Viewing multiple Subversion repositories.  SVN::Web is a full
Subversion client, so you can access repositories on the local disk
(with the C<file:///> scheme) or that are remotely accessible using
the C<http://> and C<svn://> schemes.

=item *

Browsing every revision of the repository.

=item *

Viewing the contents of files in the repository at any revision.

=item *

Viewing diffs of arbitrary revisions of any file.  Diffs can be viewed
as plain unified diffs, or HTML diffs that use colour to more easily
show what's changed.

=item *

Viewing the revision log of files and directories, see what was changed
when, by who.

=item *

Viewing the blame/annotation details of any file.

=item *

Generating RSS feeds of commits, down to the granularity of individual
files.  The RSS feeds are auto-discoverable in modern web browsers.

=item *

Viewing everything that was changed in a revision, and step through revisions
one at a time, viewing the history of the repository.

=item *

Viewing the interface in a number of different languages.  SVN::Web's
interface is fully templated and localised, allowing you to change the
look-and-feel without writing any code; all strings in the interface
are stored in a separate file, to make localising to different
languages easier.

=item *

Rich log message linking.  You can configure SVN::Web to recognise
patterns in your log messages and automatically generate links to other
web based systems.  For example, if your log messages often refer to
tickets in your request tracking system:

  Reported in: t#1234

then SVN::Web can turn C<t#1234> in to a link to that ticket.  SVN::Web
can also be configured to recognise e-mail addresses, URLs, and anything
else you wish to make clickable.

=item *

Caching.  Internally, SVN::Web caches most of the data it gets from
the repository, helping to speed up repeated visits to the same page,
and reducing the impact on your repository server.

=item *

As L<SVK> repositories are also Subversion repositories, you can do all of
the above with those too.

=back

Additional actions can easily be added to the base set supported by the
core of SVN::Web.

=head1 CONFIGURATION

Various aspects of SVN::Web's behaviour can be controlled through the
configuration file F<config.yaml>.  See the C<YAML> documentation for
information about writing YAML format files.

=head2 Version number

SVN::Web's configuration file must contain a version number.  If this
number is missing, or does not match the version number of the version
of SVN::Web that is being used then a fatal error will occur.

  version: 0.53

=head2 Repositories

=head3 Local and remote repositories

SVN::Web can show information from one or more Subversion repositories.
These repositories do not have to be located on the same server.

Repositories are specified as a hash items under the C<repos> key.  Each
key is the repository name (defined by you), the value is the repository's
URL.

The three types of repository are specified like so.

  repos:
    my_local_repo: 'file:///path/to/local/repo'
    my_http_repo: 'http://hostname/path'
    my_svn_repo: 'svn://hostname/path'

You may list as many repositories as you need.

For backwards compatibility, if a repository URL is specified without a
scheme, and starts with a C</> then the C<file:///> scheme is assumed.  So

  repos:
    my_local_repo: /path/to/local/repo

is also valid.

=head3 Local repositories under a single root

If you have multiple repositories that are all under a single parent
directory then use C<reposparent>.

  reposparent: '/path/to/parent/directory'

If you set C<reposparent> then you can selectively block certain repositories
from being browseable by specifying the C<block> setting.

  block:
    - 'first_subdir_to_block'
    - 'second_subdir_to_block'

C<repos> and C<reposparent> are mutually exclusive.

=head2 Templates

SVN::Web's output is entirely template driven.  SVN::Web ships with a
number of different template styles, installed in to the F<templates/>
subdirectory of wherever you ran C<svnweb-install>.

The default templates are installed in F<templates/trac>.  These implement
a look and feel similar to the Trac (L<http://www.edgewall.com/trac/>)
output.

To change to another set, use the C<templatedirs> configuration directive.

For example, to use a set of templates that implement a much plainer look
and feel:

  templatedirs:
    - 'template/plain'

Alternatively, if you have your own templates elsewhere you can
specify a full path to the templates.

  templatedirs:
    - '/full/path/to/template/directory'

You can specify more than one directory in this list, and templates
will be searched for in each directory in turn.  This makes it possible for
actions that are not part of the core SVN::Web to ship their own templates,
and for you to override specific templates of your choice.

For example, if an action is using a template called C<view>, and
C<templatedirs> is configured like so:

  templatedirs:
    - '/my/local/templates'
    - '/templates/that/ship/with/svn-web'

then F</my/local/templates/view> will first by checked.  If it exists
the search terminates and it's used.  If it does not exist then the search
continues in F</templates/that/ship/with/svn-web>.

For more information about writing your own templates see
L</"ACTIONS, SUBCLASSES, AND URLS">.

=head2 Languages

SVN::Web's interface is fully localised and ships with a number of
translations.  The default web interface allows the user to choose
from the available localisations at will, and the user's choice is
saved in a cookie.

=head3 Localisation directories

SVN::Web's localisation information is stored in files with names that
take the form F<< C<language>.po >>.  SVN::Web ships with a number
of localisations that are automatically installed with SVN::Web.

You can configure SVN::Web to search in additional directories for
localisation files.  There are typically three reasons for this.

=over

=item 1

You wish to add support for a new language, and have placed your
localisation files in a different directory.

=item 2

You wish to change the localisation for a language that SVN::Web already
supports, and don't wish to overwrite the localisation file that SVN::Web
ships with.

=item 3

You have installed a third party SVN::Web::action, and this action
includes its own localisation files stored in a different directory.

=back

Use the C<language_dirs> configuration to specify all the I<additional>
directories that SVN::Web should search.  For example:

  language_dirs:
    - /path/to/my/local/translation
    - /path/to/third/party/action/localisation

If files in more than one directory contain the same localisation key
for the same language then the file in the directory that is listed
I<last> in this directive will be used.

=head3 Available languages

C<languages> specifies the localisations that are considered
I<available>.  This is a hash.  The keys are the basenames of
available localisation files, the values are the language name as it
should appear in the interface.  C<svnweb-install> will have set this
to a default value.

To find the available localisation files look in the F<po/> directory
that was created in the directory in which you ran C<svnweb-install>,
and in the directories listed in the C<language_dirs> directive (if any).

For example, the default (as of SVN::Web 0.48) is:

  languages:
    en: English
    fr: Fran&ccedil;ais
    zh_cn: Chinese (Simplified)
    zh_tw: Chinese (Traditional)

=head3 Default language

C<default_language>, specifies the language to use if the user has not
selected one.  The value for this option should be one of the keys
defined in C<languages>.  For example;

  default_language: fr

=head2 Data cache

SVN::Web can use any module implementing the L<Cache::Cache> interface
to cache the data it retrieves from the repository.  Since this data does
not normally change this reduces the time it takes SVN::Web to generate
results.

This cache is B<not> enabled by default.

To enable the cache you must specify a class that implements a
L<Cache::Cache> interface.  L<Cache::SizeAwareFileCache> is a good
choice.

  cache:
    class: Cache::SizeAwareFileCache

The class' constructor may take various options.  Specify those under
the C<opts> key.

For example, L<Cache::SizeAwareFileCache> supports (among others)
options called C<max_size>, C<cache_root>, and C<directory_umask>.
These could be configured like so:

  # Use the SizeAwareFileCache.  Place it under /var/tmp instead of
  # the default (/tmp), use a custom umask, and limit the cache size to
  # 1MB
  cache:
    class: Cache::SizeAwareFileCache
    opts:
      max_size: 1000000
      cache_root: /var/tmp/svn-web-cache
      directory_umask: 077

B<Note:> The C<namespace> option, if specified, is ignored, and is always
set to the name of the repository being accessed.

=head2 Template cache

Template Toolkit can cache the results of template processing to make
future processing faster.

By default the cache is not enabled.  Use C<tt_compile_dir> to enable it.
Set this directive to the name of a directory where the UID that SVN::Web is
being run as can create files.

For example:

   tt_compile_dir: /var/tmp/tt-cache

A literal C<.> and the UID of the process running SVN::Web will be appended
to this string to generate the final directory name.  For example, if
SVN::Web is being run under UID 80 then the final directory name is
F</var/tmp/tt-cache.80>.  Since the cached templates are always created
with mode 0600 this ensures that different users running SVN::Web can not
overwrite one another's cached templates.

This directive has no default value.  If it is not defined then no caching
will take place.

=head2 Log message filters

Many of the templates shipped with SVN::Web include log messages from
the repository.  It's likely that these log messages contain e-mail
addresses, links to other web sites, and other rich information.

The Template::Toolkit makes it possible to filter these messages through
one or more plugins and/or filters that can recognise these and insert
additional markup to make them active.

In SVN::Web this is accomplished using a Template::Toolkit MACRO called
C<log_msg>.  The F<trac> templates define this in a template called
F<_log_msg>, which is included in the relevant templates by this line:

  [% PROCESS _log_msg %]

You may redefine this macro yourself to filter log messages through
additional plugins depending on your requirements.  As a MACRO this
also has access to the template's variables, allowing you to easily
specify different filters depending on the values of different
variables (perhaps per-repository, or per-author filtering).  See the
F<_log_msg> template included with this distribution for more details.

=head2 Time and date formatting

There are a number of places in the web interface where SVN::Web will
display a timestamp from Subversion.

Internally, Subversion stores times in UTC.  You may wish to show them in
your local timezone (or some other timezone).  You may also wish to change
the formatting of the timestamp.

To do this use the C<timezone> and C<timedate_format> configuration options.

C<timezone> takes one of three settings.

=over

=item 1.

If not set, or set to the empty string, SVN::Web will show all times in
UTC.  This is the default behaviour.

=item 2.

If set to the string C<local> then SVN::Web will adjust all timestamps to
the web server's local timezone (which may not be the same timezone as
the server that hosts the repository).

=item 3.

If set to a timezone name, such as C<BST> or C<EST>, then SVN::Web will
adjust all timestamps to that timezone.

=back

When displaying timestamps SVN::Web uses the L<POSIX> C<strftime()>
function.  You can change the format string that is provided, thereby
changing how the timestamp is formatted.  Use the C<timedate_format>
configuration directive for this.

The default value is:

  timedate_format: '%Y/%m/%d %H:%M:%S'

Using this format, a quarter past one in the afternoon on the 15th of
May 2006 would appear as:

  2006/05/15 13:15:00

If instead that was:

  timedate_format: '%a. %b %d, %l:%M%p'

then the same timestamp would appear as:

  Mon. May 15, 1:15pm

Note that strftime(3) on different operating systems supports different
format specifiers, so consult your system's strftime(3) manual page to
see which specifiers are available.

=head2 Actions, action classes, and action options

Each action that SVN::Web can carry out is implemented as a class (see
L</"ACTIONS, SUBCLASSES, AND URLS"> for more).  You can specify your own
class for a particular action.  This lets you implement your own actions,
or override the behaviour of existing actions.

The complete list of actions is listed in the C<actions> configuration
directive.

If you delete items from this list then the corresponding action becomes
unavailable.  For example, if you would like to prevent people from retrieving
an RSS feed of changes, just delete the C<- rss> entry from the list.

To provide your own behaviour for standard actions just specify a
different value for the C<class> key.  For example, to specify your
own class that implements the C<view> action;

  actions:
    ...
    view:
      class: My::View::Class
    ...

If you wish to implement your own action, give the action a name, add
it to the C<actions> list, and then specify the class that carries out
the action.

For example, SVN::Web currently provides no action that generates ATOM
feeds.  If you implement this, you would write:

  actions:
    ...
    atom:
      class: My::Class::That::Implements::Atom
    ...

Please feel free to submit any classes that implement additional
functionality back to the maintainers, so that they can be included in
the distribution.

Actions may have configurable options specified in F<config.yaml> under
the C<opts> key.  Continuing the C<annotate> example, the action may be
written to provide basic output by default, but feature a C<verbose>
flag that you can enable globally.  That would be configured like so:

  actions:
    ...
    annotate:
      class: My::Class::That::Implements::Annotate
      opts:
        verbose: 1
    ...

The documentation for each action should explain in more detail how it
should be configured.  See L<SVN::Web::action> for more information
about writing actions.

If an action is listed in C<actions> and there is no corresponding
C<class> directive then SVN::Web takes the action name, converts the
first character to uppercase, and then looks for an
C<< SVN::Web::<Action> >> package.

=head2 Action menu configuration

In the user interface the C<action menu> is a list of actions that are
valid in the current context.  This menu is built up programmatically
from additional metadata about each action included in the config file.

The metadata is written as a hash, with each key corresponding to a
particular piece of metadata.  The hash is rooted at the C<action_menu>
key.

A worked example may prove instructive.  Here is the default entry for
L<SVN::Web::RSS>.  This shows all the valid keys under C<action_menu>.

  rss:
    class: SVN::Web::RSS
    action_menu:
      show:
        - file
        - directory
      link_text: (rss)
      head_only: 1
      icon: /css/trac/feed-icon-16x16.png

The keys, and their meanings, are:

=over

=item show

The contexts in which this action should appear in the action menu.  Each
SVN::Web action produces a result in a particular context.  The valid
contexts are:

=over

=item file

The action is acting on a single file.  E.g., L<SVN::Web::View> or
L<SVN::Web::Blame>.

=item directory

The action is acting on a single directory.  E.g., L<SVN::Web::Browse>.

=item revision

The action is acting on a single revision.  E.g., L<SVN::Web::Revision>.

=back

Valid values are any of the three items above, plus the special value
C<global>, indicating that the action should always appear in the
action menu.

In this example, the C<rss> action is available when browsing directories
and viewing files.  It makes no sense to make the RSS action available
when browsing an individual revision, so that is not listed as a valid
context.

=item link_text

The text that should appear in the action menu for this item.  This
text is passed through the localisation system.

=item head_only

A boolean that indicates whether the action is always available in the
listed contexts, or whether it should only appear when viewing the
HEAD revision in a particular context.

In this example it makes no sense to clamp the RSS feed to a particular
revision, so it is flagged as only being available when looking at the
HEAD of a file or directory.

=item icon

The (relative) path to the icon to use for this menu item (if any).

=back

For comparison, this is the recommended setting for L<SVN::Web::Checkout>.

  checkout:
    class: SVN::Web::Checkout
    action_menu:
      show:
        - file
      link_text: (checkout)

This action is only valid when viewing files -- checking out a directory
does not make sense.  A file can be checked out at any revision, so
C<head_only> can be omitted (C<head_only: 0> would have the same effect).
And there is no icon for this action.

For details of how this information is used see the
F<template/trac/_action_menu> template.

The C<action_menu> metadata is optional.  Some actions might not merit
a menu option (e.g., C<diff> or C<revision>), so those actions should
not have C<action_menu> metadata.

=head2 CGI class

SVN::Web can use a custom CGI class.  By default SVN::Web will use
L<CGI::Fast> if it is installed, and fallback to using L<CGI> otherwise.

Of course, if you have your own class that implements the CGI interface
you may specify it here too.

  cgi_class: 'My::CGI::Subclass'

=head1 ACTIONS, SUBCLASSES, AND URLS

SVN::Web URLs are broken down in to four components.

  .../index.cgi/<repo>/<action>/<path>?<arguments>

or

  .../apache-handler/<repo>/<action>/<path>?<arguments>

=over 4

=item I<repo>

The repository the action will be performed on.  SVN::Web can be
configured to operate on multiple Subversion repositories.

=item I<action>

The action that will be run.

=item I<path>

The path within the <repository> that the action is performed on.

=item I<arguments>

Any arguments that control the behaviour of the I<action>.

=back

Each action is implemented as a Perl module.  By convention, each module
carries out whatever processing is required by the action, and returns a
reference to a hash of data that is used to fill out a C<Template::Toolkit>
template that displays the action's results.

The standard actions, and the Perl modules that implement them, are:

=over 4

=item I<blame>, I<SVN::Web::Blame>

Shows the blame (also called annotation) information for a file.  On a
per line basis it shows the revision in which that line was last changed
and the user that committed the change.

=item I<browse>, I<SVN::Web::Browse>

Shows the files and directories in a given repository path.  This is
the default command if no path is specified in the URL.

=item I<checkout>, I<SVN::Web::Checkout>

Returns the raw data for the file at a given repository path and revision.

=item I<diff>, I<SVN::Web::Diff>

Shows the difference between two revisions of the same file.

=item I<list>, I<SVN::Web::List>

Lists the available Subversion repositories.  This is the default
command if no repository is specified in the URL.

=item I<log>, I<SVN::Web::Log>

Shows log information (commit messages) for a given repository path.

=item I<revision>, I<SVN::Web::Revision>

Shows information about a specific repository revision.

=item I<rss>, I<SVN::Web::RSS>

Generates an RSS feed of changes to the repository path.

=item I<view>, I<SVN::Web::View>

Shows the commit message and file contents for a specific repository path
and revision.

=back

See the documentation for each of these modules for more information
about the data that they provide to each template, and for information
about customising the templates used for each module.

=head1 WEB SERVERS

This section explains how to configure some common webservers to run
SVN::Web.  In all cases, C</path/to/svnweb> in the examples is the
directory you ran C<svnweb-install> in, and contains F<config.yaml>.

SVN::Web now uses L<Plack> to provide connectivity to the web server.
Previously a cgi, stand alone, fastcgi, mod_perl1 and a mod_perl2
interface was provided as part of this software. All of which have been
removed and replaced by Plack. In doing so, Plack now will connect
SVN::Web to all of the above, plus PSGI, nginx_perl and anything else
cooked up in the future.

If you've configured a web server that isn't listed here for SVN::Web,
please send in the instructions so they can be included in a future
release.

=head2 plackup

C<plackups> is a simple web server that can run SVN::Web stand alone,
and is included and installed by Plack.  It may be all you need to
productively use SVN::Web without needing to install a larger server.
To use it, run:

  plackup SVN-Web.psgi

See C<perldoc plackup> for details about additional options you can
use.

=head2 Apache as CGI (not recommended)

See L<Plack::Handler::CGI>

=head2 Apache with mod_perl or mod_perl2

See L<Plack::Handler::Apache1> or L<Plack::Handler::Apache2> respectively.

=head2 Apache with FastCGI

See L<Plack::Handler::FCGI>

=head2 IIS

For now this is probably broken.

=head1 SEE ALSO

L<SVN::Web::action>, svnweb-install(1), plackup(1), L<Plack>

=head1 BUGS

Please report any bugs or feature requests to
C<bug-svn-web@rt.cpan.org>, or through the web interface at
L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=SVN-Web>.
I will be notified, and then you'll automatically be notified of progress on
your bug as I make changes.

=head1 AUTHORS

Chia-liang Kao C<< <clkao@clkao.org> >>

Nik Clayton C<< <nik@FreeBSD.org> >>

Dean Hamstead C<< <dean@fragfest.com.au> >>

=head1 COPYRIGHT

Copyright 2003-2004 by Chia-liang Kao C<< <clkao@clkao.org> >>.

Copyright 2005-2007 by Nik Clayton C<< <nik@FreeBSD.org> >>.

Copyright 2012 by Dean Hamstead C<< <dean@fragfest.com.au> >>.

This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.

See L<http://www.perl.com/perl/misc/Artistic.html>

=cut