=head1 NAME

SuikaWiki::Implementation --- SuikaWiki : Wiki Core Implementation

=cut

package SuikaWiki::Implementation;
use strict;
our $VERSION = do{my @r=(q$Revision: 1.3 $=~/\d+/g);sprintf "%d."."%02d" x $#r,@r};

our $INTERFACE_VERSION = v2.9.1;

=head1 METHODS

=over 4

=item $wiki = SuikaWiki::Implementation->new ()

Constructs new instance of wiki implementation

=cut

sub new ($;%) {
  my $self = bless {
    implementation_name => 'SuikaWiki',
    implementation_version => 'impl'.$VERSION,
    interface_version => $INTERFACE_VERSION,
  }, shift;
  
  $self;
}

=item $wiki->init_variables

Initialize per-access variables.  This method should be called
before other init_* methods are to be called.

=cut

sub init_variables ($) {
  my $self = shift;
  $self->{var} = {};
  $self->__raise_event (name => 'setting_initial_variables');
}

=item $wiki->init_plugin

Prepares to use wiki plugins

=cut

sub init_plugin ($) {
  my $self = shift;
  require SuikaWiki::Plugin;
  $self->{plugin} = SuikaWiki::Plugin->new;
  
  $self->__raise_event (name => 'plugin_manager_loaded');
}

=item $wiki->init_view

Prepares to use wikiview

=cut

sub init_view ($) {
  my $self = shift;
  require SuikaWiki::View::Implementation;
  $self->{view} = SuikaWiki::View::Implementation->new (wiki => $self);

  $self->__raise_event (name => 'view_implementation_loaded');
}

=item $wiki->init_db

Prepares to use wiki database

=cut

sub init_db ($) {
  my $self = shift;
  return if ref $self->{db};  ## Already initialized
  $self->{config}->{lock}
    = {-directory => $self->{config}->{path_to}->{db__lock__dir},
       -retry     => 20,
       -error_handler => sub {
                    my ($self, %o) = @_;
                    if ($self->{config}->{path_to}->{db__content__error_log}) {
                      open LOG, '>>', $self->{config}->{path_to}
                                           ->{db__content__error_log};
                        print LOG scalar (gmtime),
                                  "\@@{[time]} @{[$$]} {$o{level}}: LOCK: ",
                                  $o{msg}, "\n";
                      close LOG;
                    }
                    if ($o{level} eq 'fatal') {
                      die $o{msg};
                    }
       },
      };
  $self->{var}->{db}->{lock_prop} = sub {
    my $prop = shift;
    my %lock = %{$self->{config}->{lock}};
    $lock{-name} = $prop;
    $lock{-share} = defined $self->{var}->{db}->{read_only}->{$prop}
                  ? $self->{var}->{db}->{read_only}->{$prop}
                  : $self->{var}->{db}->{read_only}->{'#default'};
    \%lock;
  };
  
  require SuikaWiki::DB::Util;
  SuikaWiki::DB::Util->error_handler->{-error_handler} = sub {
    my ($self, $err_type, $err_msg, $err) = @_;
    $err_msg = caller (3) . '-->' . caller (2) . '-->' . caller (1)
             . ($err->{method} ? '->'.$err->{method} : '')
             . ': '
             . (defined $err->{file} ? $err->{file} . ': ' : '')  
             . (defined $err->{prop} ? $err->{prop} . ': ' : '')
             . (defined $err->{key} ? join ('//', @{$err->{key}}) . ': ' : '')
             . $err_msg;
    if ($self->{config}->{path_to}->{db__content__error_log}) {
      open LOG, '>>', $self->{config}->{path_to}->{db__content__error_log};
        print LOG scalar (gmtime), " @{[$$]} {$err_type->{level}}: ",
                  $err_msg, "\n";
      close LOG;
    }
    if ($err_type->{level} eq 'fatal' || $err_type->{level} eq 'stop') {
      require Carp;
      local $Carp::Verbose = 1;
      Carp::croak $err_msg;
    }
  };
  
  require SuikaWiki::DB::Logical;
  $self->{db} = new SuikaWiki::DB::Logical;
  
  $self->__raise_event (name => 'database_loaded');
}

=item $wiki->view_in_mode (%opt)

Doing main process in accordance to the mode.

Actually, this method only raises an event of 'view_in_mode'.
So that "doing main process" code should be registered as an event procedure
of 'view_in_mode'.

=cut

sub view_in_mode ($%) {
  my ($self, %opt) = @_;
  $self->__raise_event (name => 'view_in_mode', argv => [\%opt]);
}

sub __raise_event ($%) {
  my ($self, %o) = @_;
  for (@{$self->{event}->{$o{name}}||[]}) {
    &{$_} ($self, @{$o{argv}||[]});
    ## TODO: canceling
  }
  1;
}

=item $string = $wiki->version

Returns version string of the WikiEngine implementation.
This value is combination of the SuikaWiki Interface version and
implementation's version.

=cut

sub version ($) {
  my ($self) = @_;
  sprintf '%vd-%s', $self->{interface_version}, $self->{implementation_version};
}

=item $wiki->exit

Exits wiki

=cut

sub exit ($) {
  my $self = shift;
  if ($self->__raise_event (name => 'close')) {
    $self->{db}->close if ref $self->{db};
    undef $self->{db};
  }
}

sub DESTROY ($) {
  my $self = shift;
  if (ref $self->{db}) {
    $self->exit;
  }
}

=back

=head1 PUBLIC PROPERTIES

=over 4

=item $wiki->{config}

Persistent wiki configureation parameters
(that is not changed with the situation when is who accessing in what way)

=over 4

=item ->{charset}->{internal} = <IANA charset name (in lower case)>

Character encoding scheme used in wiki implementation

=item ->{charset}->{output} = <IANA charset name (in lower case)>

Default character encoding scheme used to output content

=item ->{entity}->{expires}->{$rulename} = {delta => $seconds}

How long outputed entity will be fresh.

=item ->{lock}

Default (prototype) properties to give SuikaWiki::DB::Util::Lock

=item ->{page}->{ $name }

WikiPage which has feature of $name

=item ->{path_to}->{ $name }

Filesystem path (or path fragment) to $name

=back

=item $wiki->{db}

Wiki main database

=item @{$wiki->{event}->{ $event_name }}

Event handling procedures

Standarized event names:

=over 4

=item database_loaded

When WikiDatabase manager is loaded.  This event handler is typically
used to set database property module for SuikaWiki::DB::Logical.

=item plugin_manager_loaded

When WikiPlugin manager is loaded.  Note that plugins themselves are not
loaded yet.

=item setting_initial_variables

On the process to set per-access variables.
This event is raised before other core modules such as WikiDatabase
or WikiPlugin are loaded.

=back

=item $wiki->{implementation_name} (default 'SuikaWiki')

Product name of the WikiEngine.

For interoperability, only alphanumeric characters and limited symbols
(those allowed in RFC 2616 token) should be used as parts of product name.

=item $wiki->{implementation_version} (default "impl$VERSION")

WikiEngine implementation's version in string.

For interoperability, only alphanumeric characters and limited symbols
(those allowed in RFC 2616 token) should be used as parts of product name.

=item $wiki->{interface_version} (Read only)

SuikaWiki Interface version implemented by this wiki implementation
in v-string format.

=item $wiki->{var}

Non-persistent wiki variable options
(that might vary with context such as caller's argument values)

=over 4

=item ->{client}->{used_for_negotiation} = [<HTTP field name>s]

HTTP (request) header field names used to select variable content.
This value will be used to generate HTTP Vary header field.

=item ->{client}->{user_agent_name} = <HTTP User-Agent field body value>

User agent name provided by such ways as User-Agent field (in HTTP) 
or HTTP_USER_AGENT meta variable (in HTTP-CGI).

=item ->{db}->{lock_prop} = sub ($prop)

Function returning hash reference of lock options
(that will be passed to SuikaWiki::DB::Util::Lock->new).

$prop, an argument to the function, is a database property name.

=item ->{db}->{read_only}->{ $prop } = 1/0

Whether the database property named as $prop is opened in read only
mode or not.  Special property name of '#default' is used to set
the default value referred when {read_only}->{$prop} is not specified
explicily.

Note that this value must be set before the instance of database property
is loaded.

=item ->{input}

Instance of input parameter interface (such as SuikaWiki::Input::HTTP)

=item ->{mode} = mode name

Wiki mode name

=item ->{page} = [page]

WikiPage being referred

=back

=item $wiki->{view}

WikiView implementation (an instance of SuikaWiki::View::Implementation)

=cut

=head1 LICENSE

Copyright 2003 Wakaba <w@suika.fam.cx>

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

=cut

1; # $Date: 2003/10/30 07:45:46 $