<?php
// $Id: flag.module,v 1.11.2.79 2010-08-24 09:32:55 mooffie Exp $

/**
 * @file
 * The Flag module.
 */

include_once dirname(__FILE__) .'/flag.inc';

/**
 * Implementation of hook_menu().
 */
function flag_menu() {
  $items = array();

  $items['admin/build/flags'] = array(
    'title' => 'Flags',
    'page callback' => 'flag_admin_page',
    'access callback' => 'user_access',
    'access arguments' => array('administer flags'),
    'description' => 'Configure flags for marking content with arbitary information (such as <em>offensive</em> or <em>bookmarked</em>).',
    'file' => 'includes/flag.admin.inc',
    'type' => MENU_NORMAL_ITEM,
  );
  $items['admin/build/flags/edit'] = array(
    'title' => 'Edit flags',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('flag_form'),
    'access callback' => 'user_access',
    'access arguments' => array('administer flags'),
    'file' => 'includes/flag.admin.inc',
    'type' => MENU_CALLBACK,
  );
  $items['admin/build/flags/delete'] = array(
    'title' => 'Delete flags',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('flag_delete_confirm'),
    'access callback' => 'user_access',
    'access arguments' => array('administer flags'),
    'file' => 'includes/flag.admin.inc',
    'type' => MENU_CALLBACK,
  );
  $items['admin/build/flags/list'] = array(
    'title' => 'List',
    'page callback' => 'flag_admin_page',
    'access callback' => 'user_access',
    'access arguments' => array('administer flags'),
    'file' => 'includes/flag.admin.inc',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -1,
  );
  $items['admin/build/flags/add'] = array(
    'title' => 'Add',
    'page callback' => 'flag_add_page',
    'access callback' => 'user_access',
    'access arguments' => array('administer flags'),
    'file' => 'includes/flag.admin.inc',
    'type' => MENU_LOCAL_TASK,
  );
  $items['flag'] = array(
    'title' => 'Flag',
    'page callback' => 'flag_page',
    'access callback' => 'user_access',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );
  $items['flag/confirm'] = array(
    'title' => 'Flag confirm',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('flag_confirm'),
    'access callback' => 'user_access',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );

  return $items;
}

/**
 * Implementation of hook_init().
 */
function flag_init() {
  $path = drupal_get_path('module', 'flag');
  if (module_exists('trigger')) {
    include_once $path .'/includes/flag.actions.inc';
  }
  if (module_exists('token')) {
    include_once $path .'/includes/flag.token.inc';
  }
}

/**
 * Implementation of hook_views_api().
 */
function flag_views_api() {
  return array(
    'api' => 2.0,
    'path' => drupal_get_path('module', 'flag') . '/includes',
  );
}

/**
 * Implementation of hook_perm().
 */
function flag_perm() {
  return array('administer flags');
}

/**
 * Access checking to check an account for flagging ability.
 *
 * See documentation for $flag->user_access().
 */
function flag_access($flag, $account = NULL) {
  return $flag->user_access($account);
}

/**
 * Content type checking to see if a flag applies to a certain type of data.
 *
 * @param $flag
 *   The flag object whose available types are being checked.
 * @param $content_type
 *   The type of content being checked, usually "node".
 * @param $content_subtype
 *   The subtype (node type) being checked.
 *
 * @return
 *   Boolean TRUE if the flag is enabled for this type and subtype.
 *   FALSE otherwise.
 */
function flag_content_enabled($flag, $content_type, $content_subtype = NULL) {
  $return = $flag->content_type == $content_type && (!isset($content_subtype) || in_array($content_subtype, $flag->types));
  return $return;
}

/**
 * Implementation of hook_link().
 */
function flag_link($type, $object = NULL, $teaser = FALSE) {
  if (!isset($object) || !flag_fetch_definition($type)) {
    return;
  }
  global $user;

  // Anonymous users can't create flags with this system.
  if (!$user->uid) {
    return;
  }

  // Get all possible flags for this content-type.
  $flags = flag_get_flags($type);

  foreach ($flags as $flag) {
    if (!$flag->user_access($user)) {
      // User has no permission to use this flag.
      continue;
    }
    if (!$flag->uses_hook_link($teaser)) {
      // Flag is not configured to show its link here.
      continue;
    }
    if (!$flag->applies_to_content_object($object)) {
      // Flag does not apply to this content.
      continue;
    }

    $content_id = $flag->get_content_id($object);
    // The flag links are actually fully rendered theme functions.
    // The HTML attribute is set to TRUE to allow whatever the themer desires.
    $links['flag-'. $flag->name] = array(
      'title' => $flag->theme($flag->is_flagged($content_id) ? 'unflag' : 'flag', $content_id),
      'html' => TRUE,
    );
  }

  if (isset($links)) {
    return $links;
  }
}

/**
 * Implementation of hook_flag_link().
 *
 * When Flag uses a link type provided by this module, it will call this
 * implementation of hook_flag_link(). It returns a single link's attributes,
 * using the same structure as hook_link(). Note that "title" is provided by
 * the Flag configuration if not specified here.
 *
 * @param $flag
 *   The full flag object of for the flag link being generated.
 * @param $action
 *   The action this link will perform. Either 'flag' or 'unflag'.
 * @param $content_id
 *   The ID of the node, comment, user, or other object being flagged.
 * @return
 *   An array defining properties of the link.
 */
function flag_flag_link($flag, $action, $content_id) {
  $token = flag_get_token($content_id);
  return array(
    'href' => "flag/". ($flag->link_type == 'confirm' ? 'confirm/' : '') ."$action/$flag->name/$content_id",
    'query' => drupal_get_destination() . ($flag->link_type == 'confirm' ? '' : '&token='. $token),
  );
}

/**
 * Implementation of hook_flag_link_types().
 */
function flag_flag_link_types() {
  return array(
    'toggle' => t('JavaScript toggle'),
    'normal' => t('Normal link'),
    'confirm' => t('Confirmation form'),
  );
}

/**
 * Implementation of hook_content_extra_fields().
 *
 * Informations for non-CCK 'node fields' defined in core.
 */
function flag_content_extra_fields($type_name) {
  $extra = array();
  $flags = flag_get_flags('node', $type_name);

  // Filter out flags which need to be included on the node form.
  foreach ($flags as $name => $flag) {
    if (!$flag->show_on_form) {
      unset($flags[$name]);
    }
  }

  if (!empty($flags)) {
    $extra['flag'] = array(
      'label' => t('Flags'),
      'description' => t('Flags fieldset.'),
      'weight' => 0
    );
  }
  return $extra;
}

/**
 * Implementation of hook_form_alter().
 */
function flag_form_alter(&$form, &$form_state, $form_id) {

  global $user;
  if ($form_id == 'node_type_form' && isset($form['identity']['type'])) {
    $flags = flag_get_flags('node', $form['#node_type']->type, $user);
    foreach ($flags as $flag) {
      if ($flag->show_on_form) {
        $var = 'flag_'. $flag->name .'_default';
        $form['workflow']['flag'][$var] = array(
          '#type' => 'checkbox',
          '#title' => $flag->get_label('flag_short'),
          '#default_value' => variable_get($var .'_'. $form['#node_type']->type, 0),
          '#return_value' => 1,
        );
      }
    }

    if (isset($form['workflow']['flag'])) {
      $form['workflow']['flag'] += array(
        '#type' => 'item',
        '#title' => t('Default flags'),
        '#description' => t('Above are the <a href="@flag-url">flags</a> you elected to show on the node editing form. You may specify their initial state here.', array('@flag-url' => url('admin/build/flags'))),
        // Make the spacing a bit more compact:
        '#prefix' => '<div class="form-checkboxes">',
        '#suffix' => '</div>',
      );
    }
  }
  elseif (isset($form['type']) && isset($form['#node'])
      && ($form_id == $form['type']['#value'] .'_node_form')) {
    if (!$user->uid) {
      return;
    }

    $nid = !empty($form['nid']['#value']) ? $form['nid']['#value'] : NULL;

    $flags = flag_get_flags('node', $form['type']['#value'], $user);

    // Filter out flags which need to be included on the node form.
    foreach ($flags as $name => $flag) {
      if (!$flag->show_on_form) {
        unset($flags[$name]);
      }
    }

    if (count($flags)) {
      $form['flag'] = array(
        '#type' => 'fieldset',
        '#weight' => module_exists('content') ? content_extra_field_weight($form['#node']->type, 'flags') : 1,
        '#tree' => TRUE,
        '#title' => t('Flags'),
        '#collapsible' => TRUE,
      );
    }

    foreach ($flags as $flag) {
      if (isset($form['#node']->flag[$flag->name])) {
        $flag_status = $form['#node']->flag[$flag->name];
      }
      else {
        $flag_status_default = variable_get('flag_' . $flag->name . '_default_' . $form['type']['#value'], 0);
        $flag_status = $nid ? $flag->is_flagged($nid) : $flag_status_default;
      }
      $form['flag'][$flag->name] = array(
        '#type' => 'checkbox',
        '#title' => $flag->get_label('flag_short', $nid),
        '#description' => $flag->get_label('flag_long', $nid),
        '#default_value' => $flag_status,
        '#return_value' => 1,
      );
    }
  }
}

/**
 * Implementation of hook_nodeapi().
 */
function flag_nodeapi(&$node, $op, $teaser = NULL, $page = NULL) {
  global $user;
  switch ($op) {
    case 'update':
    case 'insert':
      // Response to the flag checkboxes added to the form in flag_form_alter().
      $remembered = FALSE;
      if (isset($node->flag)) {
        foreach ($node->flag as $name => $state) {
          $flag = flag_get_flag($name);
          // Flagging may trigger actions. We want actions to get the current
          // node, not a stale database-loaded one:
          if (!$remembered) {
            $flag->remember_content($node->nid, $node);
            // Actions may modify a node, and we don't want to overwrite this
            // modification:
            $remembered = TRUE;
          }
          flag($state ? 'flag' : 'unflag', $name, $node->nid);
        }
      }
      break;
    case 'delete':
      foreach (flag_get_flags('node') as $flag) {
        // If the flag is being tracked by translation set and the node is part
        // of a translation set, don't delete the flagging record.
        // Instead, data will be updated in the 'translation_change' op, below.
        if (!$flag->i18n || empty($node->tnid)) {
          db_query("DELETE FROM {flag_content} WHERE fid = %d AND content_id = %d", $flag->fid, $node->nid);
          db_query("DELETE FROM {flag_counts} WHERE fid = %d AND content_id = %d", $flag->fid, $node->nid);
        }
      }
      break;
    case 'translation_change':
      if (isset($node->translation_change)) {
        // If there is only one node remaining, track by nid rather than tnid.
        // Otherwise, use the new tnid.
        $content_id = $node->translation_change['new_tnid'] == 0 ? $node->translation_change['remaining_nid'] : $node->translation_change['new_tnid'];
        foreach (flag_get_flags('node') as $flag) {
          if ($flag->i18n) {
            db_query("UPDATE {flag_content} SET content_id = %d WHERE fid = %d AND content_id = %d", $content_id, $flag->fid, $node->translation_change['old_tnid']);
            db_query("UPDATE {flag_counts} SET content_id = %d WHERE fid = %d AND content_id = %d", $content_id, $flag->fid, $node->translation_change['old_tnid']);
          }
        }
      }
      break;
  }
}

/**
 * Implementation of hook_user().
 */
function flag_user($op, &$edit, &$account, $category = NULL) {
  switch ($op) {
    case 'delete':
      // Remove flags by this user.
      $result = db_query("SELECT fc.fid, fc.content_id, c.count FROM {flag_content} fc LEFT JOIN {flag_counts} c ON fc.content_id = c.content_id AND fc.content_type = c.content_type WHERE fc.uid = %d", $account->uid);
      while ($flag_data = db_fetch_object($result)) {
        $flag_data->count--;
        db_query("UPDATE {flag_counts} SET count = %d WHERE fid = %d AND content_id = %d", $flag_data->count, $flag_data->fid, $flag_data->content_id);
      }
      db_query("DELETE FROM {flag_content} WHERE uid = %d", $account->uid);
      break;
    case 'view';
      $flags = flag_get_flags('user');
      $flag_items = array();
      foreach ($flags as $flag) {
        if (!$flag->user_access()) {
          // User has no permission to use this flag.
          continue;
        }
        if (!$flag->applies_to_content_object($account)) {
          // Flag does not apply to this content.
          continue;
        }
        if (!$flag->uses_hook_link(array())){
          // Flag not set to appear on profile.
          continue;
        }
        $flag_items[$flag->name] = array(
          '#type' => 'user_profile_item',
          '#title' => $flag->get_title($account->uid),
          '#value' => $flag->theme($flag->is_flagged($account->uid) ? 'unflag' : 'flag', $account->uid),
          '#attributes' => array('class' => 'flag-profile-' . $flag->name),
        );
      }
      if (!empty($flag_items)) {
        $account->content['flags'] = $flag_items;
        $account->content['flags'] += array(
          '#type' => 'user_profile_category',
          '#title' => t('Actions'),
          '#attributes' => array('class' => 'flag-profile'),
        );
      }
      break;
  }
}

/**
 * Implementation of hook_node_type().
 */
function flag_node_type($op, $info) {
  switch ($op) {
    case 'delete':
      // Remove entry from flaggable content types.
      db_query("DELETE FROM {flag_types} WHERE type = '%s'", $info->type);
      break;
  }
}

/**
 * Menu callback for (un)flagging a node.
 *
 * Used both for the regular callback as well as the JS version.
 */
function flag_page($action = NULL, $flag_name = NULL, $content_id = NULL) {
  $js = isset($_REQUEST['js']);
  $token = $_REQUEST['token'];

  // Check the flag token, then perform the flagging.
  if (!flag_check_token($token, $content_id)) {
    $error = t('Bad token. You seem to have followed an invalid link.');
  }
  else {
    $result = flag($action, $flag_name, $content_id);
    if (!$result) {
      $error = t('You are not allowed to flag, or unflag, this content.');
    }
  }

  // If an error was received, set a message and exit.
  if (isset($error)) {
    if ($js) {
      drupal_set_header('Content-Type: text/javascript; charset=utf-8');
      print drupal_to_js(array(
        'status' => FALSE,
        'errorMessage' => $error,
      ));
      exit;
    }
    else {
      drupal_set_message($error);
      drupal_access_denied();
      return;
    }
  }

  // If successful, return data according to the request type.
  if ($js) {
    drupal_set_header('Content-Type: text/javascript; charset=utf-8');
    $flag = flag_get_flag($flag_name);
    $flag->link_type = 'toggle';
    print drupal_to_js(array(
      'status' => TRUE,
      'newLink' => $flag->theme($flag->is_flagged($content_id) ? 'unflag' : 'flag', $content_id, TRUE),
      // Further information for the benefit of custom JavaScript event handlers:
      'contentId' => $content_id,
      'contentType' => $flag->content_type,
      'flagName' => $flag->name,
      'flagStatus' => $flag->is_flagged($content_id) ? 'flagged' : 'unflagged',
    ));
    exit;
  }
  else {
    $flag = flag_get_flag($flag_name);
    drupal_set_message($flag->get_label($action . '_message', $content_id));
    drupal_goto();
  }
}

/**
 * Form for confirming the (un)flagging of a piece of content.
 */
function flag_confirm(&$form_state, $action = 'flag', $flag_name, $content_id = '') {
  $form = array();

  $form['action'] = array(
    '#type' => 'value',
    '#value' => $action,
  );
  $form['flag_name'] = array(
    '#type' => 'value',
    '#value' => $flag_name,
  );
  $form['content_id'] = array(
    '#type' => 'value',
    '#value' => $content_id,
  );

  $flag = flag_get_flag($flag_name);
  $question = $flag->get_label($action .'_confirmation', $content_id);
  $path = isset($_GET['destination']) ? $_GET['destination'] : '<front>';
  $yes = $flag->get_label($action .'_short', $content_id);

  return confirm_form($form, $question, $path, '', $yes);
}

function flag_confirm_submit(&$form, &$form_state) {
  $action = $form_state['values']['action'];
  $flag_name = $form_state['values']['flag_name'];
  $content_id = $form_state['values']['content_id'];

  $result = flag($action, $flag_name, $content_id);
  if (!$result) {
    drupal_set_message(t('You are not allowed to flag, or unflag, this content.'));
  }
  else {
    $flag = flag_get_flag($flag_name);
    drupal_set_message($flag->get_label($action . '_message', $content_id));
  }
}

/**
 * Flags or unflags an item.
 *
 * @param $account
 *   The user on whose behalf to flag. Leave empty for the current user.
 * @return
 *   FALSE if some error occured (e.g., user has no permission, flag isn't
 *   applicable to the item, etc.), TRUE otherwise.
 */
function flag($action, $flag_name, $content_id, $account = NULL) {
  if (!($flag = flag_get_flag($flag_name))) {
    // Flag does not exist.
    return FALSE;
  }
  return $flag->flag($action, $content_id, $account);
}

/**
 * Implementation of hook_flag(). Trigger actions if any are available.
 */
function flag_flag($action, $flag, $content_id, $account) {
  if (module_exists('trigger')) {

    $flag_action = $flag->get_flag_action($content_id);
    $flag_action->action = $action;
    $context = (array)$flag_action;
    $aids = _trigger_get_hook_aids($action, $action);
    foreach ($aids as $aid => $action_info) {
      // The 'if ($aid)' is a safeguard against http://drupal.org/node/271460#comment-886564
      if ($aid) {
        actions_do($aid, $flag, $context);
      }
    }

  }

  if (module_exists('rules')) {
    $event_name = ($action == 'flag' ? 'flag_flagged_' : 'flag_unflagged_') . $flag->name;
    $arguments = array('flag' => $flag, 'flag_content_id' => $content_id, 'flagging_user' => $account);
    rules_invoke_event($event_name, $arguments);
  }
}

/**
 * Implementation of hook_node_operations().
 *
 * Add additional options on the admin/build/node page.
 */
function flag_node_operations() {
  global $user;

  $flags = flag_get_flags('node', NULL, $user);
  $operations = array();

  foreach ($flags as $flag) {
    $operations['flag_'. $flag->name] = array(
      'label' => $flag->get_label('flag_short'),
      'callback' => 'flag_nodes',
      'callback arguments' => array('flag', $flag->name),
      'behavior' => array(),
    );
    $operations['unflag_'. $flag->name] = array(
      'label' => $flag->get_label('unflag_short'),
      'callback' => 'flag_nodes',
      'callback arguments' => array('unflag', $flag->name),
      'behavior' => array(),
    );
  }
  return $operations;
}

/**
 * Callback function for hook_node_operations().
 */
function flag_nodes($nodes, $action, $flag_name) {
  $performed = FALSE;
  foreach ($nodes as $nid) {
    $performed |= flag($action, $flag_name, $nid);
  }
  // Drupal 6 doesn't display a confirmation message itself, so it's our responsibility.
  if ($performed) {
    drupal_set_message(t('The update has been performed.'));
  }
}

/**
 * Implementation of hook_mail().
 */
function flag_mail($key, &$message, $params) {
  switch ($key) {
    case 'over_threshold':
      $message['subject'] = $params['subject'];
      $message['body'] = $params['body'];
      break;
  }
}

/**
 * Implementation of hook_theme().
 */
function flag_theme() {
  $path = drupal_get_path('module', 'flag') .'/theme';

  return array(
    'flag' => array(
      'arguments' => array('flag' => NULL, 'action' => NULL, 'content_id' => NULL, 'after_flagging' => FALSE),
      'template' => 'flag',
      'pattern' => 'flag__',
      'path' => $path,
    ),
    'flag_token_help' => array(
      'arguments' => array('types' => NULL, 'prefix' => NULL, 'suffix' => NULL),
    ),
    'flag_admin_page' => array(
      'arguments' => array('flags' => NULL, 'default_flags' => NULL),
    ),
    'flag_rules_radios' => array(
      'arguments' => array(),
    ),
  );
}

/**
 * A preprocess function for our theme('flag'). It generates the
 * variables needed there.
 *
 * The $variables array initially contains the following arguments:
 * - $flag
 * - $action
 * - $content_id
 * - $after_flagging
 *
 * See 'flag.tpl.php' for their documentation.
 *
 * Note: The Drupal 5 version of this module calls this function directly.
 */
function template_preprocess_flag(&$variables) {
  static $first_time = TRUE;

  // Some typing shotcuts:
  $flag =& $variables['flag'];
  $action = $variables['action'];
  $content_id = $variables['content_id'];

  // Generate the link URL.
  $link_types = flag_get_link_types();
  $link_type_module = $link_types[$flag->link_type]['module'];
  $link = module_invoke($link_type_module, 'flag_link', $flag, $action, $content_id);
  if (isset($link['title']) && empty($link['html'])) {
    $link['title'] = check_plain($link['title']);
  }

  if ($flag->link_type == 'toggle' && $first_time) {
    $variables['setup'] = $first_time;
    $first_time = FALSE;
  }
  else {
    $variables['setup'] = FALSE;
  }

  $variables['link_href'] = check_url(url($link['href'], $link));
  $variables['link_text'] = isset($link['title']) ? $link['title'] : $flag->get_label($action . '_short', $content_id);
  $variables['link_title'] = isset($link['attributes']['title']) ? check_plain($link['attributes']['title']) : check_plain(strip_tags($flag->get_label($action . '_long', $content_id)));
  $variables['flag_name_css'] = str_replace('_', '-', $flag->name);
  $variables['last_action'] = ($action == 'flag' ? 'unflagged' : 'flagged');
  $variables['flag_classes_array'] = array();
  $variables['flag_classes_array'][] = 'flag';
  $variables['flag_classes_array'][] = $variables['action'] .'-action';
  $variables['flag_classes_array'][] = 'flag-link-'. $flag->link_type;

  if (isset($link['attributes']['class'])) {
    $variables['flag_classes_array'][] = $link['attributes']['class'];
  }

  if ($variables['after_flagging']) {
    $inverse_action = ($action == 'flag' ? 'unflag' : 'flag');
    $variables['message_text'] = $flag->get_label($inverse_action . '_message', $content_id);
    $variables['flag_classes_array'][] = $variables['last_action'];
  }

  $variables['flag_classes'] = implode(' ', $variables['flag_classes_array']);
}

/**
 * Format a string containing a count of items.
 *
 * _flag_format_plural() is a version of format_plural() which
 * accepts the format string as a single argument, where the singular and
 * plural forms are separated by pipe. A 'zero' form is allowed as well.
 *
 * _flag_format_plural() is used where we want the admin, not the
 * programmer, to be able to nicely and easily format a number.
 *
 * If three forms are provided, separated by pipes, then the first is
 * considered the zero form and is used if $count is 0. The zero form may
 * well be an empty string.
 *
 * @param $count
 *   The item count to display.
 * @param $format
 *   The singular, plural, and optionally the zero, forms separated
 *   by pipe characters.
 * @return
 *   A formatted, translated string.
 *
 * Examples for $format:
 *
 * @code
 *   "@count"
 *   "1 vote|@count votes"
 *   "needs voting|1 vote|@count votes"
 *   "|1 vote|@count votes"
 *   "|@count|@count"
 * @endcode
 */
function _flag_format_plural($count, $format) {
  $elements = explode('|', $format ? $format : '@count', 3);

  if (count($elements) == 3) {
    list($zero, $singular, $plural) = $elements;
  }
  elseif (count($elements) == 2) {
    list($singular, $plural) = $elements;
    $zero = NULL;
  }
  else { // count($elements) == 1
    $singular = $plural = $elements[0];
    $zero = NULL;
  }

  if (isset($zero) && intval($count) == 0) {
    return $zero;
  }
  else {
    return format_plural(intval($count), $singular, $plural);
  }
}

/**
 * Return an array of flag names keyed by fid.
 */
function _flag_get_flag_names() {
  $flags = flag_get_flags();
  $flag_names = array();
  foreach ($flags as $flag) {
    $flag_names[$flag->fid] = $flag->name;
  }
  return $flag_names;
}

/**
 * Return an array of flag link types suitable for a select list or radios.
 */
function _flag_link_type_options() {
  $options = array();
  $types = flag_get_link_types();
  foreach ($types as $type_name => $type) {
    $options[$type_name] = $type['title'];
  }
  return $options;
}

// ---------------------------------------------------------------------------
// Non-Views public API

/**
 * Get flag counts for all flags on a node.
 *
 * @param $content_type
 *   The content type (usually 'node').
 * @param $content_id
 *   The content ID (usually the node ID).
 * @param $reset
 *   Reset the internal cache and execute the SQL query another time.
 *
 * @return $flags
 *   An array of the structure [name] => [number of flags].
 */
function flag_get_counts($content_type, $content_id, $reset = FALSE) {
  static $counts;

  if ($reset) {
    $counts = array();
    if (!isset($content_type)) {
      return;
    }
  }

  if (!isset($counts[$content_type][$content_id])) {
    $counts[$content_type][$content_id] = array();
    $result = db_query("SELECT f.name, fc.count FROM {flags} f LEFT JOIN {flag_counts} fc ON f.fid = fc.fid WHERE fc.content_type = '%s' AND fc.content_id = %d", $content_type, $content_id);
    while ($row = db_fetch_object($result)) {
      $counts[$content_type][$content_id][$row->name] = $row->count;
    }
  }

  return $counts[$content_type][$content_id];
}

/**
 * Load a single flag either by name or by flag ID.
 *
 * @param $name
 *   The the flag name.
 * @param $fid
 *   The the flag id.
 */
function flag_get_flag($name = NULL, $fid = NULL) {
  $flags = flag_get_flags();
  if (isset($name)) {
    if (isset($flags[$name])) {
      return $flags[$name];
    }
  }
  elseif (isset($fid)) {
    foreach ($flags as $flag) {
      if ($flag->fid == $fid) {
        return $flag;
      }
    }
  }
}

/**
 * List all flags available.
 *
 * If node type or account are entered, a list of all possible flags will be
 * returned.
 *
 * @param $content_type
 *   Optional. The type of content for which to load the flags. Usually 'node'.
 * @param $content_subtype
 *   Optional. The node type for which to load the flags.
 * @param $account
 *   Optional. The user accont to filter available flags. If not set, all
 *   flags for will this node will be returned.
 * @param $reset
 *   Optional. Reset the internal query cache.
 *
 * @return $flags
 *   An array of the structure [fid] = flag_object.
 */
function flag_get_flags($content_type = NULL, $content_subtype = NULL, $account = NULL, $reset = FALSE) {
  static $flags;

  // Retrieve a list of all flags, regardless of the parameters.
  if (!isset($flags) || $reset) {
    $flags = array();

    // Database flags.
    $result = db_query("SELECT f.*, fn.type FROM {flags} f LEFT JOIN {flag_types} fn ON fn.fid = f.fid");
    while ($row = db_fetch_object($result)) {
      if (!isset($flags[$row->name])) {
        $flags[$row->name] = flag_flag::factory_by_row($row);
      }
      else {
        $flags[$row->name]->types[] = $row->type;
      }
    }

    // Add code-based flags provided by modules.
    $default_flags = flag_get_default_flags();
    foreach ($default_flags as $name => $default_flag) {
      // Insert new enabled flags into the database to give them an FID.
      if ($default_flag->status && !isset($flags[$name])) {
        $default_flag->save();
        $flags[$name] = $default_flag;
      }

      if (isset($flags[$name])) {
        // Ensure overridden flags are associated with their parent module.
        $flags[$name]->module = $default_flag->module;

        // Update the flag with any properties that are "locked" by the code version.
        if (isset($default_flag->locked)) {
          $flags[$name]->locked = $default_flag->locked;
          foreach ($default_flag->locked as $property) {
            $flags[$name]->$property = $default_flag->$property;
          }
        }
      }
    }
  }

  // Make a variable copy to filter types and account.
  $filtered_flags = $flags;

  // Filter out flags based on type and subtype.
  if (isset($content_type) || isset($content_subtype)) {
    foreach ($filtered_flags as $name => $flag) {
      if (!flag_content_enabled($flag, $content_type, $content_subtype)) {
        unset($filtered_flags[$name]);
      }
    }
  }

  // Filter out flags based on account permissions.
  if (isset($account) && $account->uid != 1) {
    foreach ($filtered_flags as $name => $flag) {
      if (!flag_access($flag, $account)) {
        unset($filtered_flags[$name]);
      }
    }
  }

  return $filtered_flags;
}

/**
 * Retrieve a list of flags defined by modules.
 *
 * @param $include_disabled
 *   Unless specified, only enabled flags will be returned.
 * @return
 *   An array of flag prototypes, not usable for flagging. Use flag_get_flags()
 *   if needing to perform a flagging with any enabled flag.
 */
function flag_get_default_flags($include_disabled = FALSE) {
  $default_flags = array();
  $flag_status = variable_get('flag_default_flag_status', array());

  foreach (module_implements('flag_default_flags') as $module) {
    $function = $module . '_flag_default_flags';
    foreach ($function() as $config) {
      $flag = flag_flag::factory_by_array($config);
      $flag->module = $module;
      // Add flags that have been enabled.
      if ((!isset($flag_status[$flag->name]) && (!isset($flag->status) || $flag->status)) || !empty($flag_status[$flag->name])) {
        $flag->status = TRUE;
        $default_flags[$flag->name] = $flag;
      }
      elseif ($include_disabled) {
        $flag->status = FALSE;
        $default_flags[$flag->name] = $flag;
      }
    }
  }

  return $default_flags;
}

/**
 * Find what a user has flagged, either a single node or on the entire site.
 *
 * @param $content_type
 *   The type of content that will be retrieved. Usually 'node'.
 * @param $content_id
 *   Optional. The content ID to check for flagging. If none given, all
 *   content flagged by this user will be returned.
 * @param $uid
 *   Optional. The user ID whose flags we're checking. If none given, the
 *   current user will be used.
 * @param $reset
 *   Reset the internal cache and execute the SQL query another time.
 *
 * @return $flags
 *   If returning a single node's flags, an array of the structure
 *   [flag_name] => (fcid => [fcid], uid => [uid], content_id => [content_id], timestamp => [timestamp], ...)
 *
 *   If returning all nodes, an array of arrays for each flag:
 *   [flag_name] => [content_id] => Object from above.
 *
 */
function flag_get_user_flags($content_type, $content_id = NULL, $uid = NULL, $reset = FALSE) {
  static $flagged_content;

  if ($reset) {
    $flagged_content = array();
    if (!isset($content_type)) {
      return;
    }
  }

  $uid = !isset($uid) ? $GLOBALS['user']->uid : $uid;

  if (isset($content_id)) {
    if (!isset($flagged_content[$uid][$content_type][$content_id])) {
      $flag_names = _flag_get_flag_names();
      $flagged_content[$uid][$content_type][$content_id] = array();
      $result = db_query("SELECT * FROM {flag_content} WHERE content_type = '%s' AND content_id = %d AND (uid = %d OR uid = 0)", $content_type, $content_id, $uid);
      while ($flag_content = db_fetch_object($result)) {
        $flagged_content[$uid][$content_type][$content_id][$flag_names[$flag_content->fid]] = $flag_content;
      }
    }
    return $flagged_content[$uid][$content_type][$content_id];
  }

  else {
    if (!isset($flagged_content[$uid][$content_type]['all'])) {
      $flag_names = _flag_get_flag_names();
      $flagged_content[$uid][$content_type]['all'] = array();
      $result = db_query("SELECT * FROM {flag_content} WHERE content_type = '%s' AND (uid = %d OR uid = 0)", $content_type, $uid);
      while ($flag_content = db_fetch_object($result)) {
        $flagged_content[$uid][$content_type]['all'][$flag_names[$flag_content->fid]][$flag_content->content_id] = $flag_content;
      }
    }
    return $flagged_content[$uid][$content_type]['all'];
  }

}

/**
 * Return a list of users who have flagged a piece of content.
 */
function flag_get_content_flags($content_type, $content_id, $reset = FALSE) {
  static $content_flags;

  if (!isset($content_flags[$content_type][$content_id]) || $reset) {
    $flag_names = _flag_get_flag_names();
    $result = db_query("SELECT * FROM {flag_content} WHERE content_type = '%s' AND content_id = %d ORDER BY timestamp DESC", $content_type, $content_id);
    while ($flag_content = db_fetch_object($result)) {
      $content_flags[$content_type][$content_id]['users'][$flag_content->uid][$flag_names[$flag_content->fid]] = $flag_content;
    }
  }

  return $content_flags[$content_type][$content_id]['users'];
}

/**
 * A utility function for outputting a flag link.
 *
 * You should call this function from your template when you want to put the
 * link on the page yourself. For example, you could call this function from
 * your 'node.tpl.php':
 *
 *   <?php print flag_create_link('bookmarks', $node->nid); ?>
 *
 * @param $flag_name
 *   The "machine readable" name of the flag; e.g. 'bookmarks'.
 * @param $content_id
 *   The content ID to check for flagging. This is usually a node ID.
 */
function flag_create_link($flag_name, $content_id) {
  $flag = flag_get_flag($flag_name);
  if (!$flag) {
    // Flag does not exist.
    return;
  }
  if (!$flag->user_access()) {
    // User has no permission to use this flag.
    return;
  }
  if (!$flag->applies_to_content_id($content_id)) {
    // Flag does not apply to this content.
    return;
  }
  return $flag->theme($flag->is_flagged($content_id) ? 'unflag' : 'flag', $content_id);
}

/**
 * Return an array of link types provided by modules.
 */
function flag_get_link_types($reset = FALSE) {
  static $link_types;

  if (!isset($link_types) || $reset) {
    $link_types = array();
    foreach (module_implements('flag_link_types') as $module) {
      $module_types = module_invoke($module, 'flag_link_types');
      foreach ($module_types as $type_name => $type_title) {
        $link_types[$type_name] = array(
          'module' => $module,
          'title' => $type_title,
        );
      }
    }
  }

  return $link_types;
}

/**
 * Get a private token used to protect links from spoofing - CSRF.
 */
function flag_get_token($nid) {
  return drupal_get_token($nid);
}

/**
 * Check to see if a token value matches the specified node.
 */
function flag_check_token($token, $seed) {
  return drupal_get_token($seed) == $token;
}