<?php
// $Id: views_premium.inc,v 1.0 2007/10/15 Exp $

/**
 * This include file implements views functionality on behalf of premium.module
 */

function premium_views_tables() {
  $tables['premium'] = array(
    'name' => 'premium',
    'provider' => 'internal',
    'join' => array(
      'left' => array(
        'table' => 'node',
        'field' => 'nid'
      ),
      'right' => array(
        'field' => 'nid'
      ),
    ),

    'filters' => array(
      'nid' => array(
        'name' => t('Node: Premium Content'),
        'operator' => array('=' => t('Equals')),
        'list' => 'views_handler_operator_yesno',
        'list-type' => 'select',
        'handler' => 'premium_views_handler_filter_nid_exist',
        'help' => t('Filter by whether or not the node is premium content.'),
      ),
    ),
  );
  return $tables;
}

/**
 * Views handler for filtering whether or not the node is premium content.
 */
function premium_views_handler_filter_nid_exist($op, $filter, $filterdata, &$query) {
  switch ($op) {
    case 'handler':
      $query->ensure_table('premium');
      if ($filter['value']) {
        $query->add_where('premium.nid');
      }
      else {
        $query->add_where('ISNULL(premium.nid)');
      }
      break;
  }
}