--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/includes/actions.inc	Tue Dec 23 14:28:28 2008 +0100
@@ -0,0 +1,365 @@
+<?php
+// $Id: actions.inc,v 1.8 2007/12/31 14:51:04 goba Exp $
+
+/**
+ * @file
+ * This is the actions engine for executing stored actions.
+ */
+
+/**
+ * Perform a given list of actions by executing their callback functions.
+ *
+ * Given the IDs of actions to perform, find out what the callbacks
+ * for the actions are by querying the database. Then call each callback
+ * using the function call $function($object, $context, $a1, $2)
+ * where $function is the name of a function written in compliance with
+ * the action specification; that is, foo($object, $context).
+ *
+ * @param $action_ids
+ *   The ID of the action to perform. Can be a single action ID or an array
+ *   of IDs. IDs of instances will be numeric; IDs of singletons will be
+ *   function names.
+ * @param $object
+ *   Parameter that will be passed along to the callback. Typically the
+ *   object that the action will act on; a node, user or comment object.
+ *   If the action does not act on an object, pass a dummy object. This
+ *   is necessary to support PHP 4 object referencing.
+ * @param $context
+ *   Parameter that will be passed along to the callback. $context is a
+ *   keyed array containing extra information about what is currently
+ *   happening at the time of the call. Typically $context['hook'] and
+ *   $context['op'] will tell which hook-op combination resulted in this
+ *   call to actions_do().
+ * @param $a1
+ *   Parameter that will be passed along to the callback.
+ * @param $a2
+ *   Parameter that will be passed along to the callback.
+ *
+ * @return
+ *   An associative array containing the result of the function that
+ *   performs the action, keyed on action ID.
+ */
+function actions_do($action_ids, &$object, $context = NULL, $a1 = NULL, $a2 = NULL) {
+  static $stack;
+  $stack++;
+  if ($stack > variable_get('actions_max_stack', 35)) {
+    watchdog('actions', 'Stack overflow: too many calls to actions_do(). Aborting to prevent infinite recursion.', WATCHDOG_ERROR);
+    return;
+  }
+  $actions = array();
+  $available_actions = actions_list();
+  $result = array();
+  if (is_array($action_ids)) {
+    $where = array();
+    $where_values = array();
+    foreach ($action_ids as $action_id) {
+      if (is_numeric($action_id)) {
+        $where[] = 'OR aid = %d';
+        $where_values[] = $action_id;
+      }
+      elseif (isset($available_actions[$action_id])) {
+        $actions[$action_id] = $available_actions[$action_id];
+      }
+    }
+
+    // When we have action instances we must go to the database to
+    // retrieve instance data.
+    if ($where) {
+      $where_clause = implode(' ', $where);
+      // Strip off leading 'OR '.
+      $where_clause = '('. strstr($where_clause, " ") .')';
+      $result_db = db_query('SELECT * FROM {actions} WHERE '. $where_clause, $where_values);
+      while ($action = db_fetch_object($result_db)) {
+        $actions[$action->aid] = $action->parameters ? unserialize($action->parameters) : array();
+        $actions[$action->aid]['callback'] = $action->callback;
+        $actions[$action->aid]['type'] = $action->type;
+      }
+    }
+
+    // Fire actions, in no particular order.
+    foreach ($actions as $action_id => $params) {
+      if (is_numeric($action_id)) { // Configurable actions need parameters.
+        $function = $params['callback'];
+        $context = array_merge($context, $params);
+        $result[$action_id] = $function($object, $context, $a1, $a2);
+      }
+      // Singleton action; $action_id is the function name.
+      else {
+        $result[$action_id] = $action_id($object, $context, $a1, $a2);
+      }
+    }
+  }
+  // Optimized execution of single action.
+  else {
+    // If it's a configurable action, retrieve stored parameters.
+    if (is_numeric($action_ids)) {
+      $action = db_fetch_object(db_query("SELECT * FROM {actions} WHERE aid = %d", $action_ids));
+      $function = $action->callback;
+      $context = array_merge($context, unserialize($action->parameters));
+      $result[$action_ids] = $function($object, $context, $a1, $a2);
+    }
+    // Singleton action; $action_ids is the function name.
+    else {
+      $result[$action_ids] = $action_ids($object, $context, $a1, $a2);
+    }
+  }
+  return $result;
+}
+
+
+/**
+ * Discover all action functions by invoking hook_action_info().
+ *
+ * mymodule_action_info() {
+ *   return array(
+ *     'mymodule_functiondescription_action' => array(
+ *       'type' => 'node',
+ *       'description' => t('Save node'),
+ *       'configurable' => FALSE,
+ *       'hooks' => array(
+ *         'nodeapi' => array('delete', 'insert', 'update', 'view'),
+ *         'comment' => array('delete', 'insert', 'update', 'view'),
+ *       )
+ *     )
+ *   );
+ * }
+ *
+ * The description is used in presenting possible actions to the user for
+ * configuration. The type is used to present these actions in a logical
+ * grouping and to denote context. Some types are 'node', 'user', 'comment',
+ * and 'system'. If an action is configurable it will provide form,
+ * validation and submission functions. The hooks the action supports
+ * are declared in the 'hooks' array.
+ *
+ * @param $reset
+ *   Reset the action info static cache.
+ *
+ * @return
+ *   An associative array keyed on function name. The value of each key is
+ *   an array containing information about the action, such as type of
+ *   action and description of the action, e.g.,
+ *
+ *   @code
+ *   $actions['node_publish_action'] = array(
+ *     'type' => 'node',
+ *     'description' => t('Publish post'),
+ *     'configurable' => FALSE,
+ *     'hooks' => array(
+ *       'nodeapi' => array('presave', 'insert', 'update', 'view'),
+ *       'comment' => array('delete', 'insert', 'update', 'view'),
+ *     ),
+ *   );
+ *   @endcode
+ */
+function actions_list($reset = FALSE) {
+  static $actions;
+  if (!isset($actions) || $reset) {
+    $actions = module_invoke_all('action_info');
+    drupal_alter('action_info', $actions);
+  }
+
+  // See module_implements for explanations of this cast.
+  return (array)$actions;
+}
+
+/**
+ * Retrieve all action instances from the database.
+ *
+ * Compare with actions_list() which gathers actions by
+ * invoking hook_action_info(). The two are synchronized
+ * by visiting /admin/build/actions (when actions.module is
+ * enabled) which runs actions_synchronize().
+ *
+ * @return
+ *   Associative array keyed by action ID. Each value is
+ *   an associative array with keys 'callback', 'description',
+ *   'type' and 'configurable'.
+ */
+function actions_get_all_actions() {
+  $actions = array();
+  $result = db_query("SELECT * FROM {actions}");
+  while ($action = db_fetch_object($result)) {
+    $actions[$action->aid] = array(
+      'callback' => $action->callback,
+      'description' => $action->description,
+      'type' => $action->type,
+      'configurable' => (bool) $action->parameters,
+    );
+  }
+  return $actions;
+}
+
+/**
+ * Create an associative array keyed by md5 hashes of function names.
+ *
+ * Hashes are used to prevent actual function names from going out into
+ * HTML forms and coming back.
+ *
+ * @param $actions
+ *   An associative array with function names as keys and associative
+ *   arrays with keys 'description', 'type', etc. as values. Generally
+ *   the output of actions_list() or actions_get_all_actions() is given
+ *   as input to this function.
+ *
+ * @return
+ *   An associative array keyed on md5 hash of function name. The value of
+ *   each key is an associative array of function, description, and type
+ *   for the action.
+ */
+function actions_actions_map($actions) {
+  $actions_map = array();
+  foreach ($actions as $callback => $array) {
+    $key = md5($callback);
+    $actions_map[$key]['callback']     = isset($array['callback']) ? $array['callback'] : $callback;
+    $actions_map[$key]['description']  = $array['description'];
+    $actions_map[$key]['type']         = $array['type'];
+    $actions_map[$key]['configurable'] = $array['configurable'];
+  }
+  return $actions_map;
+}
+
+/**
+ * Given an md5 hash of a function name, return the function name.
+ *
+ * Faster than actions_actions_map() when you only need the function name.
+ *
+ * @param $hash
+ *   MD5 hash of a function name
+ *
+ * @return
+ *   Function name
+ */
+function actions_function_lookup($hash) {
+  $actions_list = actions_list();
+  foreach ($actions_list as $function => $array) {
+    if (md5($function) == $hash) {
+      return $function;
+    }
+  }
+
+  // Must be an instance; must check database.
+  $aid = db_result(db_query("SELECT aid FROM {actions} WHERE MD5(aid) = '%s' AND parameters != ''", $hash));
+  return $aid;
+}
+
+/**
+ * Synchronize actions that are provided by modules.
+ *
+ * They are synchronized with actions that are stored in the actions table.
+ * This is necessary so that actions that do not require configuration can
+ * receive action IDs. This is not necessarily the best approach,
+ * but it is the most straightforward.
+ */
+function actions_synchronize($actions_in_code = array(), $delete_orphans = FALSE) {
+  if (!$actions_in_code) {
+    $actions_in_code = actions_list();
+  }
+  $actions_in_db = array();
+  $result = db_query("SELECT * FROM {actions} WHERE parameters = ''");
+  while ($action = db_fetch_object($result)) {
+    $actions_in_db[$action->callback] = array('aid' => $action->aid, 'description' => $action->description);
+  }
+
+  // Go through all the actions provided by modules.
+  foreach ($actions_in_code as $callback => $array) {
+    // Ignore configurable actions since their instances get put in
+    // when the user adds the action.
+    if (!$array['configurable']) {
+      // If we already have an action ID for this action, no need to assign aid.
+      if (array_key_exists($callback, $actions_in_db)) {
+        unset($actions_in_db[$callback]);
+      }
+      else {
+        // This is a new singleton that we don't have an aid for; assign one.
+        db_query("INSERT INTO {actions} (aid, type, callback, parameters, description) VALUES ('%s', '%s', '%s', '%s', '%s')", $callback, $array['type'], $callback, '', $array['description']);
+        watchdog('actions', "Action '%action' added.", array('%action' => filter_xss_admin($array['description'])));
+      }
+    }
+  }
+
+  // Any actions that we have left in $actions_in_db are orphaned.
+  if ($actions_in_db) {
+    $orphaned = array();
+    $placeholder = array();
+
+    foreach ($actions_in_db as $callback => $array) {
+      $orphaned[] = $callback;
+      $placeholder[] = "'%s'";
+    }
+
+    $orphans = implode(', ', $orphaned);
+
+    if ($delete_orphans) {
+      $placeholders = implode(', ', $placeholder);
+      $results = db_query("SELECT a.aid, a.description FROM {actions} a WHERE callback IN ($placeholders)", $orphaned);
+      while ($action = db_fetch_object($results)) {
+        actions_delete($action->aid);
+        watchdog('actions', "Removed orphaned action '%action' from database.", array('%action' => filter_xss_admin($action->description)));
+      }
+    }
+    else {
+      $link = l(t('Remove orphaned actions'), 'admin/build/actions/orphan');
+      $count = count($actions_in_db);
+      watchdog('actions', format_plural($count, 'One orphaned action (%orphans) exists in the actions table. !link', '@count orphaned actions (%orphans) exist in the actions table. !link', array('@count' => $count, '%orphans' => $orphans, '!link' => $link), 'warning'));
+    }
+  }
+}
+
+/**
+ * Save an action and its associated user-supplied parameter values to the database.
+ *
+ * @param $function
+ *   The name of the function to be called when this action is performed.
+ * @param $params
+ *   An associative array with parameter names as keys and parameter values
+ *   as values.
+ * @param $desc
+ *   A user-supplied description of this particular action, e.g., 'Send
+ *   e-mail to Jim'.
+ * @param $aid
+ *   The ID of this action. If omitted, a new action is created.
+ *
+ * @return
+ *   The ID of the action.
+ */
+function actions_save($function, $type, $params, $desc, $aid = NULL) {
+  $serialized = serialize($params);
+  if ($aid) {
+    db_query("UPDATE {actions} SET callback = '%s', type = '%s', parameters = '%s', description = '%s' WHERE aid = %d", $function, $type, $serialized, $desc, $aid);
+    watchdog('actions', 'Action %action saved.', array('%action' => $desc));
+  }
+  else {
+    // aid is the callback for singleton actions so we need to keep a
+    // separate table for numeric aids.
+    db_query('INSERT INTO {actions_aid} VALUES (default)');
+    $aid = db_last_insert_id('actions_aid', 'aid');
+    db_query("INSERT INTO {actions} (aid, callback, type, parameters, description) VALUES (%d, '%s', '%s', '%s', '%s')", $aid, $function, $type, $serialized, $desc);
+    watchdog('actions', 'Action %action created.', array('%action' => $desc));
+  }
+
+  return $aid;
+}
+
+/**
+ * Retrieve a single action from the database.
+ *
+ * @param $aid
+ *   integer The ID of the action to retrieve.
+ *
+ * @return
+ *   The appropriate action row from the database as an object.
+ */
+function actions_load($aid) {
+  return db_fetch_object(db_query("SELECT * FROM {actions} WHERE aid = %d", $aid));
+}
+
+/**
+ * Delete a single action from the database.
+ *
+ * @param $aid
+ *   integer The ID of the action to delete.
+ */
+function actions_delete($aid) {
+  db_query("DELETE FROM {actions} WHERE aid = %d", $aid);
+  module_invoke_all('actions_delete', $aid);
+}