google_appliance_suggest.module

<?php

/**
 * @file 
 * Google Appliance Suggest module enables Query Suggestions feature of Google
 * Search Appliance hardware device.
 */


/**
 * Default module settings.
 */
define('SGAS_DEFAULT_MAX', 5);
define('SGAS_DEFAULT_CACHE', 0);
define('SGAS_DEFAULT_HIDE_THROBBER', 1);
define('SGAS_DEFAULT_AUTOSUBMIT', 1);


/**
 * Implements hook_form_alter().
 *
 * Adds autocomplete functionality to both search forms provided by the Google
 * Appliance module.
 */
function google_appliance_suggest_form_alter(&$form, &$form_state, $form_id) {
  $gsa_forms = array(
    'google_appliance_block_form',
    'google_appliance_search_form',
  );

  // Apply autocomplete to both block and standard search forms.
  if (in_array($form_id, $gsa_forms)) {
    global $base_url;
    $settings = _google_appliance_suggest_get_settings();

    // Only alter the form if the module is enabled.
    if ($settings['max']) {
      // Set up the path for the autocomplete callback.
      $module = drupal_get_path('module', 'google_appliance_suggest');
      $file = 'google_appliance_suggest_callback.php';
      $autocomplete_path = $base_url . '/' . $module . '/' . $file . '?q=';

      // Attach the autocomplete callback.
      if ($form_id == 'google_appliance_search_form') {
        $form['basic']['search_keys']['#autocomplete_path'] = $autocomplete_path;
      }
      else {
        $form['search_keys']['#autocomplete_path'] = $autocomplete_path;
      }

      // If desired, hide standard Drupal autocomplete styles.
      if ($settings['hide_throbber']) {
        $form['#attached']['css'][] = $module . '/google_appliance_suggest.css';
      }

      // If desired, automatically submit the form when a query is suggested.
      if ($settings['autosubmit']) {
        $form['#attached']['js'][] = $module . '/google_appliance_suggest.js';

        // Add the auto_submit class that the JS hooks onto.
        if ($form_id == 'google_appliance_search_form') {
          $form['basic']['search_keys']['#attributes']['class'][] = 'auto_submit';
        }
        else {
          $form['search_keys']['#attributes']['class'][] = 'auto_submit';
        }
      }
    }
  }
}


/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Adds Google Search Appliance Query Suggestion settings to the main appliance
 * admin form.
 */
function google_appliance_suggest_form_google_appliance_admin_settings_alter(&$form, &$form_state, $form_id) {
  $settings = _google_appliance_suggest_get_settings();

  // Create new fieldset for query suggestion setup.
  $form['suggest_settings'] = array(
    '#title' => t('Query Suggestion Settings'),
    '#type' => 'fieldset',
    '#collapsible' => 1,
    '#collapsed' => 0,
  );

  // Field for max number of query suggestions returned.
  $form['suggest_settings']['max'] = array(
    '#title' => t('Maximum suggestions returned'),
    '#type' => 'select',
    '#options' => array(
      0 => 0,
      1 => 1,
      2 => 2,
      3 => 3,
      4 => 4,
      5 => 5,
      6 => 6,
      7 => 7,
      8 => 8,
      9 => 9,
      10 => 10,
    ),
    '#default_value' => $settings['max'],
    '#description' => t('Maximum number of query suggestions to display to the user. Setting this to 0 disables query suggestions.'),
  );

  // Switch whether or not to hide the default Drupal throbber.
  $form['suggest_settings']['hide_throbber'] = array(
    '#title' => t('Hide throbber'),
    '#type' => 'checkbox',
    '#description' => t('Hides the throbber image Drupal provides by default on auto-complete form elements.'),
    '#default_value' => $settings['hide_throbber'],
  );

  // Switch whether or not to autosubmit the form when a suggestion is selected.
  $form['suggest_settings']['autosubmit'] = array(
    '#title' => t('Auto-submit query suggestion'),
    '#type' => 'checkbox',
    '#description' => t('Automatically submits the search form when a user selects a query suggestion.'),
    '#default_value' => $settings['autosubmit'],
  );

  // Switch whether or not to enable query suggest caching.
  $form['suggest_settings']['cache'] = array(
    '#title' => t('Enable suggestion caching'),
    '#type' => 'checkbox',
    '#description' => t('Speeds up query suggestions by caching suggestion results.'),
    '#default_value' => $settings['cache'],
  );

  // Button to clear query suggestion cache.
  $form['suggest_settings']['clear_cache'] = array(
    '#type' => 'submit',
    '#value' => t('Clear suggestion cache'),
    '#submit' => array('google_appliance_suggest_clear_cache_submit'),
    '#disabled' => (boolean) !$settings['cache'],
  );

  // Add another submit handler to save query suggestion variables.
  array_unshift($form['#submit'], 'google_appliance_suggest_admin_settings_submit');
}


/**
 * Submit handler for query suggestion settings.
 */
function google_appliance_suggest_admin_settings_submit($form, &$form_state) {
  $field_keys =  array(
    'max',
    'cache',
    'hide_throbber',
    'autosubmit',
  );

  // Save settings.
  foreach ($field_keys as $field) {
    variable_set('google_appliance_suggest_' . $field, $form_state['values'][$field]);
  }
  
  // Refresh settings getter.
  $settings = _google_appliance_suggest_get_settings(TRUE);   
}

/**
 * Submit handler for suggestion cache clearing.
 */
function google_appliance_suggest_clear_cache_submit($form, &$form_state) {
  $deleted = db_delete('cache_page')
    ->condition('cid', '%google_appliance_suggest%', 'LIKE')
    ->execute();
  drupal_set_message(t('@num suggestions cleared from cache.', array('@num' => $deleted)));
}


/**
 * Helper function to get Google Appliance Suggest settings.
 *
 * @param $refresh boolean
 *   If this is set to TRUE, this function will freshly return variable settings
 *   for query suggestions.
 *
 * @return
 *   A keyed array of module settings keyed by $field_keys.
 */
function _google_appliance_suggest_get_settings($refresh = FALSE) {
  static $settings; 

  $field_keys =  array(
    'max',
    'cache',
    'hide_throbber',
    'autosubmit',
  );
  
  if ($refresh || empty($settings)) {
    foreach ($field_keys as $field) {  
      $settings[$field] = trim(variable_get(
        'google_appliance_suggest_' . $field,
        constant('SGAS_DEFAULT_' . strtoupper($field))
      ));
    
    }
  }
  return $settings;
}