Merged branch devel-api (from r2208 to r2387) back into trunk (omitting some sample plugins)

1 files changed, 312 insertions, 0 deletions

diff --git a/program/include/rcube_plugin_api.php b/program/include/rcube_plugin_api.php
new file mode 100644
index 000000000..4780f2e7e
--- /dev/null
+++ b/program/include/rcube_plugin_api.php
@@ -0,0 +1,312 @@
+<?php
+
+/*
+ +-----------------------------------------------------------------------+
+ | program/include/rcube_plugin_api.php                                  |
+ |                                                                       |
+ | This file is part of the RoundCube Webmail client                     |
+ | Copyright (C) 2008-2009, RoundCube Dev. - Switzerland                 |
+ | Licensed under the GNU GPL                                            |
+ |                                                                       |
+ | PURPOSE:                                                              |
+ |   Plugins repository                                                  |
+ |                                                                       |
+ +-----------------------------------------------------------------------+
+ | Author: Thomas Bruederli <roundcube@gmail.com>                        |
+ +-----------------------------------------------------------------------+
+
+ $Id: $
+
+*/
+
+/**
+ * The plugin loader and global API
+ *
+ * @package Core
+ */
+class rcube_plugin_api
+{
+  static private $instance;
+  
+  public $dir;
+  public $url = 'plugins/';
+  public $output;
+  
+  public $handlers = array();
+  private $plugins = array();
+  private $actions = array();
+  private $actionmap = array();
+  private $objectsmap = array();
+  private $template_contents = array();
+  
+  private  $required_plugins = array('filesystem_attachments');
+
+  /**
+   * This implements the 'singleton' design pattern
+   *
+   * @return object rcube_plugin_api The one and only instance if this class
+   */
+  static function get_instance()
+  {
+    if (!self::$instance) {
+      self::$instance = new rcube_plugin_api();
+    }
+
+    return self::$instance;
+  }
+  
+  
+  /**
+   * Private constructor
+   */
+  private function __construct()
+  {
+    $rcmail = rcmail::get_instance();
+    $this->dir = realpath($rcmail->config->get('plugins_dir'));
+  }
+  
+  
+  /**
+   * Load and init all enabled plugins
+   *
+   * This has to be done after rcmail::load_gui() or rcmail::init_json()
+   * was called because plugins need to have access to rcmail->output
+   */
+  public function init()
+  {
+    $rcmail = rcmail::get_instance();
+    $this->output = $rcmail->output;
+    
+    $plugins_dir = dir($this->dir);
+    $plugins_enabled = (array)$rcmail->config->get('plugins', array());
+    
+    foreach ($plugins_enabled as $plugin_name) {
+      $fn = $plugins_dir->path . DIRECTORY_SEPARATOR . $plugin_name . DIRECTORY_SEPARATOR . $plugin_name . '.php';
+      
+      if (file_exists($fn)) {
+        include($fn);
+        
+        // instantiate class if exists
+        if (class_exists($plugin_name, false)) {
+          $plugin = new $plugin_name($this);
+          // check inheritance and task specification
+          if (is_subclass_of($plugin, 'rcube_plugin') && (!$plugin->task || $plugin->task == $rcmail->task)) {
+            $plugin->init();
+            $this->plugins[] = $plugin;
+          }
+        }
+        else {
+          raise_error(array('code' => 520, 'type' => 'php', 'message' => "No plugin class $plugin_name found in $fn"), true, false);
+        }
+      }
+      else {
+        raise_error(array('code' => 520, 'type' => 'php', 'message' => "Failed to load plugin file $fn"), true, false);
+      }
+    }
+    
+    // check existance of all required core plugins
+    foreach ($this->required_plugins as $plugin_name) {
+      $loaded = false;
+      foreach ($this->plugins as $plugin) {
+        if ($plugin instanceof $plugin_name) {
+          $loaded = true;
+          break;
+        }
+      }
+      
+      // load required core plugin if no derivate was found
+      if (!$loaded) {
+        $fn = $plugins_dir->path . DIRECTORY_SEPARATOR . $plugin_name . DIRECTORY_SEPARATOR . $plugin_name . '.php';
+        if (file_exists($fn)) {
+          include($fn);
+          
+          if (class_exists($plugin_name, false)) {
+            $plugin = new $plugin_name($this);
+            // check inheritance
+            if (is_subclass_of($plugin, 'rcube_plugin')) {
+              $plugin->init();
+              $this->plugins[] = $plugin;
+              $loaded = true;
+            }
+          }
+        }
+      }
+      
+      // trigger fatal error if still not loaded
+      if (!$loaded) {
+        raise_error(array('code' => 520, 'type' => 'php', 'message' => "Requried plugin $plugin_name was not loaded"), true, true);
+      }
+    }
+
+    // register an internal hook
+    $this->register_hook('template_container', array($this, 'template_container_hook'));
+    
+    // maybe also register a shudown function which triggers shutdown functions of all plugin objects
+    
+    
+    // call imap_init right now
+    // (should actually be done in rcmail::imap_init() but plugins are not initialized then)
+    if ($rcmail->imap) {
+      $hook = $this->exec_hook('imap_init', array('fetch_headers' => $rcmail->imap->fetch_add_headers));
+      if ($hook['fetch_headers'])
+        $rcmail->imap->fetch_add_headers = $hook['fetch_headers'];
+    }
+  }
+  
+  
+  /**
+   * Allows a plugin object to register a callback for a certain hook
+   *
+   * @param string Hook name
+   * @param mixed String with global function name or array($obj, 'methodname')
+   */
+  public function register_hook($hook, $callback)
+  {
+    if (is_callable($callback))
+      $this->handlers[$hook][] = $callback;
+    else
+      raise_error(array('code' => 521, 'type' => 'php', 'message' => "Invalid callback function for $hook"), true, false);
+  }
+  
+  
+  /**
+   * Triggers a plugin hook.
+   * This is called from the application and executes all registered handlers
+   *
+   * @param string Hook name
+   * @param array Named arguments (key->value pairs)
+   * @return array The (probably) altered hook arguments
+   */
+  public function exec_hook($hook, $args = array())
+  {
+    $args += array('abort' => false);
+    
+    foreach ((array)$this->handlers[$hook] as $callback) {
+      $ret = call_user_func($callback, $args);
+      if ($ret && is_array($ret))
+        $args = $ret + $args;
+      
+      if ($args['abort'])
+        break;
+    }
+    
+    return $args;
+  }
+
+
+  /**
+   * Let a plugin register a handler for a specific request
+   *
+   * @param string Action name (_task=mail&_action=plugin.foo)
+   * @param string Plugin name that registers this action
+   * @param mixed Callback: string with global function name or array($obj, 'methodname')
+   */
+  public function register_action($action, $owner, $callback)
+  {
+    // check action name
+    if (strpos($action, 'plugin.') !== 0)
+      $action = 'plugin.'.$action;
+    
+    // can register action only if it's not taken or registered by myself
+    if (!isset($this->actionmap[$action]) || $this->actionmap[$action] == $owner) {
+      $this->actions[$action] = $callback;
+      $this->actionmap[$action] = $owner;
+    }
+    else {
+      raise_error(array('code' => 523, 'type' => 'php', 'message' => "Cannot register action $action; already taken by another plugin"), true, false);
+    }
+  }
+
+
+  /**
+   * This method handles requests like _task=mail&_action=plugin.foo
+   * It executes the callback function that was registered with the given action.
+   *
+   * @param string Action name
+   */
+  public function exec_action($action)
+  {
+    if (isset($this->actions[$action])) {
+      call_user_func($this->actions[$action]);
+    }
+    else {
+      raise_error(array('code' => 524, 'type' => 'php', 'message' => "No handler found for action $action"), true, true);
+    }
+  }
+
+
+  /**
+   * Register a handler function for template objects
+   *
+   * @param string Object name
+   * @param string Plugin name that registers this action
+   * @param mixed Callback: string with global function name or array($obj, 'methodname')
+   */
+  public function register_handler($name, $owner, $callback)
+  {
+    // check name
+    if (strpos($name, 'plugin.') !== 0)
+      $name = 'plugin.'.$name;
+    
+    // can register handler only if it's not taken or registered by myself
+    if (!isset($this->objectsmap[$name]) || $this->objectsmap[$name] == $owner) {
+      $this->output->add_handler($name, $callback);
+      $this->objectsmap[$name] = $owner;
+    }
+    else {
+      raise_error(array('code' => 525, 'type' => 'php', 'message' => "Cannot register template handler $name; already taken by another plugin"), true, false);
+    }
+  }
+  
+  /**
+   * Include a plugin script file in the current HTML page
+   */
+  public function include_script($fn)
+  {
+    if ($this->output->type == 'html') {
+      $src = $this->ressource_url($fn);
+      $this->output->add_header(html::tag('script', array('type' => "text/javascript", 'src' => $src)));
+    }
+  }
+
+  /**
+   * Include a plugin stylesheet in the current HTML page
+   */
+  public function include_stylesheet($fn)
+  {
+    if ($this->output->type == 'html') {
+      $src = $this->ressource_url($fn);
+      $this->output->add_header(html::tag('link', array('rel' => "stylesheet", 'type' => "text/css", 'href' => $src)));
+    }
+  }
+  
+  /**
+   * Save the given HTML content to be added to a template container
+   */
+  public function add_content($html, $container)
+  {
+    $this->template_contents[$container] .= $html . "\n";
+  }
+  
+  /**
+   * Callback for template_container hooks
+   */
+  private function template_container_hook($attrib)
+  {
+    $container = $attrib['name'];
+    return array('content' => $this->template_contents[$container]);
+  }
+  
+  /**
+   * Make the given file name link into the plugins directory
+   */
+  private function ressource_url($fn)
+  {
+    if ($fn[0] != '/' && !eregi('^https?://', $fn))
+      return $this->url . $fn;
+    else
+      return $fn;
+  }
+
+}
+