<?php
/**
 * @file
 * Subscriptions to content in groups
 * 
 * Group subscriptions are allowed for user that have view access to the group node
 * Whether a user can get a notification about a specific post will be decided later
 */

/**
 * Implementation of hook_menu_()
 */
function notifications_group_menu($may_cache) {
  global $user;  // we need the user to to build some urls
  $items = array();
  
  if ($may_cache) {
    $items[] = array(
      'path' => 'admin/notifications/settings/group',
      'title' => t('Group Subscriptions'),
      'type' => MENU_LOCAL_TASK,
      'callback' => 'drupal_get_form',
      'callback arguments' => array('notifications_group_settings_form'),
    );
  } else {
    if ($user->uid && arg(0) == 'user' && is_numeric(arg(1)) && arg(2) == 'notifications' && ($user->uid == arg(1) || user_access('administer notifications'))) {
      $account = ($user->uid == arg(1)) ? $user : user_load(array('uid' => arg(1)));
      $items[] = array(
        'path' => 'user/'. $account->uid .'/notifications/group',
        'type' => MENU_LOCAL_TASK,
        'access' => user_access('subscribe to content'),
        'title' => t('Groups'),
        'callback' => 'notifications_group_user_page',
        'callback arguments' => array($account),
        'weight' => 10,
      );
    }
  }
  return $items;
}

/**
 * Implementation of hook_perm()
 */
function notifications_group_perm() {
  return array('subscribe to content in groups');
}

/**
 * Admin settings form
 */
function notifications_group_settings_form() {
  // General content settings
  $select = array();
  $nodetypes = node_get_types();
  foreach ($nodetypes as $ntype => $nname) {
    $select[$ntype] = $nname->name;
  }

  $form['notifications_group_content_types'] = array(
    '#type'          => 'checkboxes',
    '#title'         => t('Allowed content types'),
    '#default_value' => variable_get('notifications_group_content_types', array()),
    '#options'       => $select,
    '#description'   => t('Select specific content types which should be <strong>allowed</strong> for group subscriptions.'),
    '#multiple'      => TRUE,
  );
  $form['notifications_group_link_teaser'] = array(
    '#type'          => 'checkbox',
    '#title'         => t('Show subscribe link with teaser'),
    '#default_value' => variable_get('notifications_grouplink_teaser', 1),
    '#description'   => t('Uncheck to show link only in group view.'),
  );
  return system_settings_form($form);
}

/**
 * Implementation of hook_notifications().
 */
function notifications_group_notifications($op, &$arg0, $arg1 = NULL, $arg2 = NULL) {
  switch ($op) {
    case 'names':
      $subs = &$arg0;
      if ($subs->event_type == 'node') {
        if (!empty($subs->fields['group']) && ($group = node_load($subs->fields['group']))) {
          $subs->names['group'] = t('Group: %name', array('%name' => $group->title));
        }
      }
      break;
    case 'subscription types':
      $types['group'] = array(
        'event_type' => 'node',
        'title' => t('Groups'),
        'access' => 'subscribe to content in groups',
        'page' => 'notifications_group_user_page',
        'fields' => array('group'),
      );
      $types['grouptype'] = array(
        'event_type' => 'node',
        'title' => t('Content type in group'),
        'access' => 'subscribe to content in groups',
        'fields' => array('group', 'type'),
      );
      return $types;
    case 'query':
      // $arg0 = 'event' and $arg1 = 'node' and $event = $arg2
      // $arg0 = 'user'  and $arg1 = 'noe' and $node = $arg2
      if ($arg0 == 'event' && $arg1 == 'node' && ($node = $arg2->node) || 
          $arg0 == 'user' && $arg1 == 'node' && ($node = $arg2)) 
      {
        $query = array();
        if ($node->og_groups) {
          $query[] = array(
            'join' => "LEFT JOIN {og_ancestry} og ON f.field = 'group' AND f.value = og.group_nid",
            'where' => 'og.nid = %d',
            'args' => array($node->nid),
          );
        }
        if ($arg0 == 'user' && og_is_group_type($node->type)) {
          $query[]['fields']['group'] = $node->nid;
        }
        return $query;
      }
      break;
    case 'node options':
      return _notifications_group_node_options($arg0, $arg1);
    case 'event load': // $arg0 is event
      // Nothing to load here, the user may be subscribed through one of many parent groups      
      break;
    case 'event types':
      // Event types for this are defined in notifications_content module
      break;
    case 'access':
      $type = $arg0;
      $account = &$arg1;
      $object = &$arg2;
      if ($type == 'subscription' && !empty($object->fields['group'])) {
        if (($group = node_load($object->fields['group'])) && og_is_group_type($group->type) && notifications_content_node_allow($account, $group)) {
          return array(TRUE);
        } else {
          return array(FALSE);
        }
      }
      break;
  }
}

/**
 * Options to display for node subscriptions
 */
function _notifications_group_node_options($account, $node) {
  // If node is a group type
  if (og_is_group_type($node->type)) {
    $options[] = array(
      'name' => t('To all posts in this group'),
      'type' => 'group',
      'fields' => array('group' => $node->nid),
    );

    foreach (array_filter(variable_get('notifications_group_content_types', array())) as $type) {
      $options[] = array(
        'name' => t('To %type posts in this group', array('%type' => node_get_types('name', $type))),
        'type' => 'grouptype',
        'fields' => array('group' => $node->nid, 'type' => $type),
      );
    }
  }
  // If node is part of a group user may be subscribed to the node through one of the groups
  if ($node->og_groups) {
    foreach ($node->og_groups as $index => $gid) {
      // Content type
      $options[] = array(
        'name' => t('To posts in group %name', array('%name' => $node->og_groups_names[$index])),
        'type' => 'group',
        'fields' => array('group' => $gid),
      );
      $options[] = array(
        'name' => t('To %type posts in this group', array('%type' => node_get_types('name', $node->type))),
        'type' => 'grouptype',
        'fields' => array('group' => $gid, 'type' => $node->type),
      );
    }
  }
  return $options;
}

/**
 * Menu callback. User subscriptions to groups.
 */
function notifications_group_user_page($account = NULL) {
  global $user;
  $account = $account ? $account : $user;

  // Query for group subscriptions. 
  // @ TO DO Retrieve also grouptype subscriptions
  $query = "SELECT s.*, f.value AS nid, n.type AS node_type, n.title FROM {notifications} s 
    INNER JOIN {notifications_fields} f ON s.sid = f.sid LEFT JOIN {node} n ON f.value = n.nid
    WHERE s.uid = %d AND s.type = 'group' AND s.conditions = 1 AND f.field = 'group'
    ORDER BY node_type, n.title";
  $results = db_query($query, $account->uid);

  $subscriptions = $list = array();

  while ($sub = db_fetch_object($results)) {
    $subscriptions[$sub->nid] = $sub;
    $list[$sub->nid] = $sub->title;
  }  

  if (!$subscriptions) {
    $output = t('There are no active group subscriptions.');    
  } else {
    $defaults = array('type' => 'group', 'event_type' => 'node');
    $options = array('title' => t('Group'));
    $output = drupal_get_form('notifications_user_form', $account, 'group', $subscriptions, $list, $defaults, $options);
  }
  return $output;
}