<?php
// $Id: faceted_search_views.module,v 1.18 2009/03/03 00:22:41 davidlesieur Exp $

/**
 * @file
 * Allows to use Views to display Faceted Search results.
 */

require_once('./'. drupal_get_path('module', 'faceted_search') .'/faceted_search_ui.inc');

/**
 * Implementation of hook_faceted_search_ui_style_info().
 *
 * Return display styles based on views that use the Faceted Search argument.
 */
function faceted_search_views_faceted_search_ui_style_info() {
  $styles = array();
  foreach (views_get_all_views() as $view) {
    if ($view->base_table == 'node' && empty($view->disabled) && $view->display['default']->display_options['use_pager']) {
      $styles[$view->name] = new faceted_search_views_style($view->name);
    }
  }
  return $styles;
}
	
/**
 * Implementation of hook_views_query_alter().
 */
function faceted_search_views_views_query_alter (&$view, &$query) {   
  if (is_array($view->args[0]) && isset($view->args[0]['faceted_search'])) {    
    $search = $view->args[0]['faceted_search'];
	        
    if ($search->ready()) {
      if ($search->get_results_count() > 0) {
        $join = new views_join();
        $join->construct($search->get_results_table(), 'node', 'nid', 'nid', array(), 'INNER');
        $query->add_table($search->get_results_table(), NULL, $join);        		
      }
      else {
        $query->add_where(0, 'FALSE'); // Ensure the view shows no results.
      }
    }
  }
}

/**
 * Provides a view-based display style for search results.
 */
class faceted_search_views_style extends faceted_search_ui_style {
  // Name of the view to use with this style.
  var $_name;
  
  /**
   * Constructor.
   *
   * @param $view_name
   *   Name of the view to use with this style.
   */
  function faceted_search_views_style($view_name) {
    $this->_name = $view_name;
  }

  /**
   * Return the name of this style.
   */
  function get_label() {
    return t('Views: @view', array('@view' => $this->_name));
  }

  /**
   * Return the number of nodes per page.
   */
  function get_limit() {
    $view = views_get_view($this->_name);
       
    if ($view->display['default']->display_options['items_per_page'] > 0) {
      return $view->display['default']->display_options['items_per_page'];
    }
    // The pager is mandatory for search results, thus a valid limit required.
    return variable_get('default_nodes_main', 10);
  }

  /**
   * Apply the view's count query as a subquery to filter the search results.
   *
   * Note: We use the view's count query for this purpose because we don't need
   * the sorting and field selection provided by view's full query. The view's
   * only purpose here is to filter the search results.
   */
  function query_alter(&$query, $search) {
    $view = views_get_view($this->_name);
    $view->set_display('default');
    $view->set_arguments(array('faceted_search' => $search));
    $view->build('default');
    $views_query = db_rewrite_sql($view->build_info['count_query'], $view->base_table, $view->base_field, array('view' => &$view));
    $views_args = $view->build_info['query_args'];
    $views_replacements = module_invoke_all('views_query_substitutions', $view);
    if (is_array($views_args)) {
      foreach ($views_args as $id => $arg) {
        $views_args[$id] = str_replace(array_keys($views_replacements), $views_replacements, $arg);
      }
    }
    $query->add_subquery('n.nid IN ('. $views_query .')', $views_args);
  }

  /**
   * Format the search results according to this style's desire.
   */
  function format_results($search) {
    return views_embed_view($this->_name, 'default' , array('faceted_search' => $search));
  }
}