plugins: first prototype version

git-svn-id: http://piwigo.org/svn/trunk@1578 68402e56-0260-453c-a942-63ccdbb3a9ee

13 files changed, 459 insertions, 14 deletions

diff --git a/admin.php b/admin.php
index 6617dfadc..93340855f 100644
--- a/admin.php
+++ b/admin.php
@@ -92,6 +92,7 @@ $template->assign_vars(
     'U_COMMENTS'=> $link_start.'comments',
     'U_RATING'=> $link_start.'rating',
     'U_CADDIE'=> $link_start.'element_set&cat=caddie',
+    'U_PLUGINS'=> $link_start.'plugins',
     'U_TAGS'=> $link_start.'tags',
     'U_THUMBNAILS'=> $link_start.'thumbnail',
     'U_USERS'=> $link_start.'user_list',
diff --git a/admin/include/functions_plugins.inc.php b/admin/include/functions_plugins.inc.php
new file mode 100644
index 000000000..bb85e15f6
--- /dev/null
+++ b/admin/include/functions_plugins.inc.php
@@ -0,0 +1,101 @@
+<?php
+// +-----------------------------------------------------------------------+
+// | PhpWebGallery - a PHP based picture gallery                           |
+// | Copyright (C) 2003-2006 PhpWebGallery Team - http://phpwebgallery.net |
+// +-----------------------------------------------------------------------+
+// | branch        : BSF (Best So Far)
+// | file          : $Id$
+// | last update   : $Date$
+// | last modifier : $Author$
+// | revision      : $Revision$
+// +-----------------------------------------------------------------------+
+// | This program is free software; you can redistribute it and/or modify  |
+// | it under the terms of the GNU General Public License as published by  |
+// | the Free Software Foundation                                          |
+// |                                                                       |
+// | This program is distributed in the hope that it will be useful, but   |
+// | WITHOUT ANY WARRANTY; without even the implied warranty of            |
+// | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      |
+// | General Public License for more details.                              |
+// |                                                                       |
+// | You should have received a copy of the GNU General Public License     |
+// | along with this program; if not, write to the Free Software           |
+// | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
+// | USA.                                                                  |
+// +-----------------------------------------------------------------------+
+
+function get_plugins()
+{
+  $plugins = array();
+
+  $dir = opendir(PHPWG_PLUGINS_PATH);
+  while ($file = readdir($dir))
+  {
+    if ($file!='.' and $file!='..')
+    {
+      $path = PHPWG_PLUGINS_PATH.$file;
+      if (is_dir($path) and !is_link($path)
+          and preg_match('/^[a-zA-Z0-9-_]+$/', $file )
+          and file_exists($path.'/index.php')
+          )
+      {
+        $plugin = array('name'=>'?', 'version'=>'?', 'uri'=>'', 'description'=>'');
+        $plg_data = implode( '', file($path.'/index.php') );
+
+        if ( preg_match("|Plugin Name: (.*)|i", $plg_data, $val) )
+        {
+          $plugin['name'] = trim( $val[1] );
+        }
+        if (preg_match("|Version: (.*)|i", $plg_data, $val))
+        {
+          $plugin['version'] = trim($val[1]);
+        }
+        if ( preg_match("|Plugin URI: (.*)|i", $plg_data, $val) )
+        {
+          $plugin['uri'] = $val[1];
+        }
+        if ( preg_match("|Description: (.*)|i", $plg_data, $val) )
+        {
+          $plugin['description'] = trim($val[1]);
+        }
+        $plugins[$file] = $plugin;
+      }
+    }
+  }
+  closedir($dir);
+  return $plugins;
+}
+
+function activate_plugin($plugin_name)
+{
+  global $conf;
+  $arr = get_active_plugins(false);
+  array_push($arr, $plugin_name);
+  if ($arr != array_unique($arr) )
+    return false; // just added the same one
+  $conf['active_plugins'] = implode(',', $arr);
+  pwg_query('
+UPDATE '.CONFIG_TABLE.'
+  SET value="'.$conf['active_plugins'].'"
+  WHERE param="active_plugins"');
+  return true;
+}
+
+function deactivate_plugin($plugin_name)
+{
+  global $conf;
+  $arr = get_active_plugins(false);
+  $idx = array_search($plugin_name, $arr);
+  if ($idx!==false)
+  {
+    unset( $arr[$idx] );
+    $conf['active_plugins'] = implode(',', $arr);
+    pwg_query('
+UPDATE '.CONFIG_TABLE.'
+  SET value="'.$conf['active_plugins'].'"
+  WHERE param="active_plugins"');
+    return true;
+  }
+  return false;
+}
+?>
\ No newline at end of file
diff --git a/admin/plugins.php b/admin/plugins.php
new file mode 100644
index 000000000..04c79aeca
--- /dev/null
+++ b/admin/plugins.php
@@ -0,0 +1,94 @@
+<?php
+// +-----------------------------------------------------------------------+
+// | PhpWebGallery - a PHP based picture gallery                           |
+// | Copyright (C) 2002-2003 Pierrick LE GALL - pierrick@phpwebgallery.net |
+// | Copyright (C) 2003-2005 PhpWebGallery Team - http://phpwebgallery.net |
+// +-----------------------------------------------------------------------+
+// | branch        : BSF (Best So Far)
+// | file          : $RCSfile$
+// | last update   : $Date$
+// | last modifier : $Author$
+// | revision      : $Revision$
+// +-----------------------------------------------------------------------+
+// | This program is free software; you can redistribute it and/or modify  |
+// | it under the terms of the GNU General Public License as published by  |
+// | the Free Software Foundation                                          |
+// |                                                                       |
+// | This program is distributed in the hope that it will be useful, but   |
+// | WITHOUT ANY WARRANTY; without even the implied warranty of            |
+// | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      |
+// | General Public License for more details.                              |
+// |                                                                       |
+// | You should have received a copy of the GNU General Public License     |
+// | along with this program; if not, write to the Free Software           |
+// | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
+// | USA.                                                                  |
+// +-----------------------------------------------------------------------+
+
+if( !defined("PHPWG_ROOT_PATH") )
+{
+  die ("Hacking attempt!");
+}
+
+include_once(PHPWG_ROOT_PATH.'admin/include/functions.php');
+include_once(PHPWG_ROOT_PATH.'admin/include/functions_plugins.inc.php');
+check_status(ACCESS_ADMINISTRATOR);
+
+$my_base_url = PHPWG_ROOT_PATH.'admin.php?page=plugins';
+
+if ( isset($_REQUEST['action']) and isset($_REQUEST['plugin'])  )
+{
+  if ( $_REQUEST['action']=='deactivate')
+  {
+    $result = deactivate_plugin( $_REQUEST['plugin'] );
+  }
+  else
+  {
+    $result = activate_plugin( $_REQUEST['plugin'] );
+  }
+  if ($result)
+  { // we need a redirect so that we really reload it
+    redirect($my_base_url.'&amp;'.$_REQUEST['action'].'='.$result);
+  }
+  else
+  {
+    array_push( $page['errors'], 'Plugin activation/deactivation error' );
+  }
+}
+
+
+$active_plugins = get_active_plugins();
+$active_plugins = array_flip($active_plugins);
+
+$plugins = get_plugins();
+
+$template->set_filenames(array('plugins' => 'admin/plugins.tpl'));
+
+if (count($plugins))
+{
+  $template->assign_block_vars( 'plugins', array() );
+  foreach( $plugins as $plugin_id => $plugin )
+  {
+    $action_url = $my_base_url.'&amp;plugin='.$plugin_id;
+    if ( isset( $active_plugins[$plugin_id] ) )
+    {
+      $action_url .= '&amp;action=deactivate';
+      $action_name = l10n('Deactivate');
+    }
+    else
+    {
+      $action_url .= '&amp;action=activate';
+      $action_name = l10n('Activate');
+    }
+    $template->assign_block_vars( 'plugins.plugin',
+        array(
+          'NAME' => $plugin['name'],
+          'DESCRIPTION' => $plugin['description'],
+          'L_ACTION' => $action_name,
+          'U_ACTION' => $action_url,
+          )
+       );
+  }
+}
+$template->assign_var_from_handle('ADMIN_CONTENT', 'plugins');
+?>
diff --git a/include/common.inc.php b/include/common.inc.php
index d0376afe8..e77d41f89 100644
--- a/include/common.inc.php
+++ b/include/common.inc.php
@@ -158,6 +158,8 @@ if ($user['is_the_guest'])
 // template instance
 $template = new Template(PHPWG_ROOT_PATH.'template/'.$user['template'], $user['theme'] );
 
+load_plugins();
+
 if ($conf['gallery_locked'])
 {
   $header_msgs[] = $lang['gallery_locked_message'];
@@ -191,6 +193,7 @@ if ($conf['check_upgrade_feed']
     and defined('PHPWG_IN_UPGRADE')
     and PHPWG_IN_UPGRADE)
 {
+
   // retrieve already applied upgrades
   $query = '
 SELECT id
diff --git a/include/config_default.inc.php b/include/config_default.inc.php
index c4426d711..b70b24e21 100644
--- a/include/config_default.inc.php
+++ b/include/config_default.inc.php
@@ -521,4 +521,6 @@ $conf['email_admin_on_new_user']=false;
 // stored on user informations
 //$conf['default_admin_layout']='yoga/dark';
 
+
+$conf['disable_plugins']=false;
 ?>
diff --git a/include/functions.inc.php b/include/functions.inc.php
index 2e7a47b4b..3b7c88bc6 100644
--- a/include/functions.inc.php
+++ b/include/functions.inc.php
@@ -33,6 +33,7 @@ include_once( PHPWG_ROOT_PATH .'include/functions_group.inc.php' );
 include_once( PHPWG_ROOT_PATH .'include/functions_html.inc.php' );
 include_once( PHPWG_ROOT_PATH .'include/functions_tag.inc.php' );
 include_once( PHPWG_ROOT_PATH .'include/functions_url.inc.php' );
+include_once( PHPWG_ROOT_PATH .'include/functions_plugins.inc.php' );
 
 //----------------------------------------------------------- generic functions
 
diff --git a/include/functions_plugins.inc.php b/include/functions_plugins.inc.php
new file mode 100644
index 000000000..23b6df5cd
--- /dev/null
+++ b/include/functions_plugins.inc.php
@@ -0,0 +1,155 @@
+<?php
+// +-----------------------------------------------------------------------+
+// | PhpWebGallery - a PHP based picture gallery                           |
+// | Copyright (C) 2003-2006 PhpWebGallery Team - http://phpwebgallery.net |
+// +-----------------------------------------------------------------------+
+// | branch        : BSF (Best So Far)
+// | file          : $Id$
+// | last update   : $Date$
+// | last modifier : $Author$
+// | revision      : $Revision$
+// +-----------------------------------------------------------------------+
+// | This program is free software; you can redistribute it and/or modify  |
+// | it under the terms of the GNU General Public License as published by  |
+// | the Free Software Foundation                                          |
+// |                                                                       |
+// | This program is distributed in the hope that it will be useful, but   |
+// | WITHOUT ANY WARRANTY; without even the implied warranty of            |
+// | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      |
+// | General Public License for more details.                              |
+// |                                                                       |
+// | You should have received a copy of the GNU General Public License     |
+// | along with this program; if not, write to the Free Software           |
+// | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
+// | USA.                                                                  |
+// +-----------------------------------------------------------------------+
+
+/*
+Events and event handlers are the core of PhpWebGallery plugin management.
+Plugins are addons that are found in plugins subdirectory. If activated, PWG
+will include the index.php of each plugin.
+Events are triggered by PWG core code. Plugins (or even PWG itself) can
+register their functions to handle these events. An event is identified by a
+string.
+*/
+
+define('PHPWG_PLUGINS_PATH',PHPWG_ROOT_PATH.'plugins/');
+
+/* Register a event handler.
+ * @param string $event the name of the event to listen to
+ * @param mixed $func the function that will handle the event
+*/
+function add_event_handler($event, $func, $priority=50, $accepted_args=1)
+{
+  global $pwg_event_handlers;
+
+  if ( isset($pwg_event_handlers[$event]["$priority"]) )
+  {
+    foreach($pwg_event_handlers[$event]["$priority"] as $handler)
+    {
+      if ( $handler['function'] == $func )
+      {
+        return true;
+      }
+    }
+  }
+
+  trigger_event('add_event_handler',
+      array('event'=>$event, 'function'=>$func)
+    );
+
+  $pwg_event_handlers[$event]["$priority"][] =
+    array(
+      'function'=>$func,
+      'accepted_args'=>$accepted_args);
+
+  return true;
+}
+
+
+function trigger_event($event, $data=null)
+{
+  global $pwg_event_handlers;
+  if ($event!='pre_trigger_event' and $event!='post_trigger_event')
+  {// special case
+    trigger_event('pre_trigger_event',
+        array('event'=>$event, 'data'=>$data) );
+    if ( !isset($pwg_event_handlers[$event]) )
+    {
+      trigger_event('post_trigger_event',
+          array('event'=>$event, 'data'=>$data) );
+    }
+  }
+
+  if ( !isset($pwg_event_handlers[$event]) )
+  {
+    return $data;
+  }
+  $args = array_slice(func_get_args(), 2);
+
+  foreach ($pwg_event_handlers[$event] as $priority => $handlers)
+  {
+    if ( !is_null($handlers) )
+    {
+      foreach($handlers as $handler)
+      {
+        $all_args = array_merge( array($data), $args);
+        $function_name = $handler['function'];
+        $accepted_args = $handler['accepted_args'];
+
+        if ( $accepted_args == 1 )
+          $the_args = array($data);
+        elseif ( $accepted_args > 1 )
+          $the_args = array_slice($all_args, 0, $accepted_args);
+        elseif ( $accepted_args == 0 )
+          $the_args = NULL;
+        else
+          $the_args = $all_args;
+
+        $data = call_user_func_array($function_name, $the_args);
+      }
+    }
+  }
+
+  if ($event!='pre_trigger_event' and $event!='post_trigger_event')
+  {
+    trigger_event('post_trigger_event',
+        array('event'=>$event, 'data'=>$data) );
+  }
+
+  return $data;
+}
+
+
+
+
+
+function get_active_plugins($runtime = true)
+{
+  global $conf;
+  if ($conf['disable_plugins'] and $runtime)
+  {
+    return array();
+  }
+  if (empty($conf['active_plugins']))
+  {
+    return array();
+  }
+  return explode(',', $conf['active_plugins']);
+
+}
+
+
+function load_plugins()
+{
+  $plugins = get_active_plugins();
+  foreach( $plugins as $plugin)
+  {
+    if (!empty($plugin))
+    {
+      include_once( PHPWG_PLUGINS_PATH.$plugin.'/index.php' );
+    }
+  }
+  trigger_event('plugins_loaded');
+}
+?>
\ No newline at end of file
diff --git a/include/page_header.php b/include/page_header.php
index a729e0ebc..af571ab19 100644
--- a/include/page_header.php
+++ b/include/page_header.php
@@ -37,8 +37,9 @@ $template->assign_vars(
         $page['gallery_title'] : $conf['gallery_title'],
 
     'PAGE_BANNER' =>
-      isset($page['page_banner']) ?
-        $page['page_banner'] : $conf['page_banner'],
+      trigger_event('page_banner',
+          isset($page['page_banner']) ?
+          $page['page_banner'] : $conf['page_banner'] ),
 
     'BODY_ID' =>
       isset($page['body_id']) ?
@@ -49,22 +50,22 @@ $template->assign_vars(
     'LANG'=>$lang_info['code'],
     'DIR'=>$lang_info['direction'],
 
-    'TAG_INPUT_ENABLED' => 
+    'TAG_INPUT_ENABLED' =>
       ((is_adviser()) ? 'disabled onclick="return false;"' : '')
     ));
 
-// refresh 	 
-if ( isset( $refresh ) and intval($refresh) >= 0 
+// refresh
+if ( isset( $refresh ) and intval($refresh) >= 0
     and isset( $url_link ) and isset( $redirect_msg ) )
-{ 	 
-  $template->assign_vars( 	 
-    array( 	 
-      'U_REDIRECT_MSG' => $redirect_msg, 	 
-      'REFRESH_TIME' => $refresh, 	 
-      'U_REFRESH' => $url_link 	 
-      )); 	 
-  $template->assign_block_vars('refresh', array()); 	 
-} 	 
+{
+  $template->assign_vars(
+    array(
+      'U_REDIRECT_MSG' => $redirect_msg,
+      'REFRESH_TIME' => $refresh,
+      'U_REFRESH' => $url_link
+      ));
+  $template->assign_block_vars('refresh', array());
+}
 
 header('Content-Type: text/html; charset='.$lang_info['charset']);
 $template->parse('header');
diff --git a/install/config.sql b/install/config.sql
index 22fcd428d..ec985a496 100644
--- a/install/config.sql
+++ b/install/config.sql
@@ -22,6 +22,7 @@ INSERT INTO phpwebgallery_config (param,value,comment) VALUES ('page_banner','<h
 INSERT INTO phpwebgallery_config (param,value,comment) VALUES ('history_admin','false','keep a history of administrator visits on your website');
 INSERT INTO phpwebgallery_config (param,value,comment) VALUES ('history_guest','true','keep a history of guest visits on your website');
 INSERT INTO phpwebgallery_config (param,value,comment) VALUES ('login_history','true','keep a history of user logins on your website');
+INSERT INTO phpwebgallery_config (param,value,comment) VALUES ('active_plugins','','activated plugins');
 -- Notification by mail
 INSERT INTO phpwebgallery_config (param,value,comment) VALUES ('nbm_send_mail_as','','Send mail as param value for notification by mail');
 INSERT INTO phpwebgallery_config (param,value,comment) VALUES ('nbm_send_detailed_content','true','Send detailed content for notification by mail');
diff --git a/install/db/32-database.php b/install/db/32-database.php
new file mode 100644
index 000000000..f47fec986
--- /dev/null
+++ b/install/db/32-database.php
@@ -0,0 +1,47 @@
+<?php
+// +-----------------------------------------------------------------------+
+// | PhpWebGallery - a PHP based picture gallery                           |
+// | Copyright (C) 2002-2003 Pierrick LE GALL - pierrick@phpwebgallery.net |
+// | Copyright (C) 2003-2006 PhpWebGallery Team - http://phpwebgallery.net |
+// +-----------------------------------------------------------------------+
+// | branch        : BSF (Best So Far)
+// | file          : $RCSfile$
+// | last update   : $Date: 2006-07-23 14:17:00 +0200 (dim, 23 jui 2006) $
+// | last modifier : $Author: nikrou $
+// | revision      : $Revision: 1492 $
+// +-----------------------------------------------------------------------+
+// | This program is free software; you can redistribute it and/or modify  |
+// | it under the terms of the GNU General Public License as published by  |
+// | the Free Software Foundation                                          |
+// |                                                                       |
+// | This program is distributed in the hope that it will be useful, but   |
+// | WITHOUT ANY WARRANTY; without even the implied warranty of            |
+// | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      |
+// | General Public License for more details.                              |
+// |                                                                       |
+// | You should have received a copy of the GNU General Public License     |
+// | along with this program; if not, write to the Free Software           |
+// | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
+// | USA.                                                                  |
+// +-----------------------------------------------------------------------+
+
+if (!defined('PHPWG_ROOT_PATH'))
+{
+  die('Hacking attempt!');
+}
+
+$upgrade_description = 'add active_plugins to config';
+
+// add column auto_login_key
+$query = '
+INSERT INTO '.PREFIX_TABLE.'config (param,value,comment)
+  VALUES (\'active_plugins\',\'\',\'activated plugins\')
+;';
+pwg_query($query);
+
+echo
+"\n"
+. $upgrade_description
+."\n"
+;
+?>
diff --git a/plugins/hello_world/index.php b/plugins/hello_world/index.php
new file mode 100644
index 000000000..d2a8bcddb
--- /dev/null
+++ b/plugins/hello_world/index.php
@@ -0,0 +1,18 @@
+<?php /*
+Plugin Name: Hello World !
+Author: PhpWebGallery team
+Description: This example plugin changes the page banner for the administration page
+*/
+
+add_event_handler('page_banner', 'hello_world_banner' );
+
+function hello_world_banner($banner)
+{
+  global $page;
+  if ( isset($page['body_id']) and $page['body_id']=='theAdminPage')
+  {
+    return '<h1>Hello world from PhpWebGallery plugin!</h1>';
+  }
+  return $banner;
+}
+?>
diff --git a/template/yoga/admin.tpl b/template/yoga/admin.tpl
index 24177e427..294b39b15 100644
--- a/template/yoga/admin.tpl
+++ b/template/yoga/admin.tpl
@@ -19,6 +19,7 @@
 	<li><a href="{U_CAT_UPDATE}">{lang:update}</a></li>
 	<li><a href="{U_MAINTENANCE}">{lang:Maintenance}</a></li>
 	<li><a href="{U_NOTIFICATION_BY_MAIL}">{lang:nbm_item_notification}</a></li>
+	<li><a href="{U_PLUGINS}">{lang:Plugins}</a></li>
       </ul>
     </dd>
   </dl>
diff --git a/template/yoga/admin/plugins.tpl b/template/yoga/admin/plugins.tpl
new file mode 100644
index 000000000..81bade54d
--- /dev/null
+++ b/template/yoga/admin/plugins.tpl
@@ -0,0 +1,20 @@
+<div class="titrePage">
+  <h2>{lang:Plugins}</h2>
+</div>
+
+<!-- BEGIN plugins -->
+<table>
+<thead><tr>
+  <td>{lang:Name}</td>
+  <td>{lang:Description}</td>
+  <td>{lang:Action}</td>
+</tr></thead>
+<!-- BEGIN plugin -->
+<tr>
+  <td>{plugins.plugin.NAME}</td>
+  <td>{plugins.plugin.DESCRIPTION}</td>
+  <td><a href="{plugins.plugin.U_ACTION}">{plugins.plugin.L_ACTION}</a></td>
+</tr>
+<!-- END plugin -->
+</table>
+<!-- END plugins -->
\ No newline at end of file