drupal_module__url_replace_filter/url_replace_filter.install

<?php
/**
 * @file
 * Install file for URL Replace filter.
 *
 * @author: Frédéric G. MARAND <fgm@osinet.fr>
 *
 * @license General Public License version 2.0 or later
 */

/**
 * Implementation of hook_requirements().
 *
 * Ensure the module is actually used in at least one filter.
 */
function url_replace_filter_requirements($phase) {
  if ($phase != 'runtime') {
    return array();
  }

  $formats = _url_replace_filter_get_formats();
  $filter_id = 'url_replace_filter/0';
  $count = 0;
  foreach ($formats as $format) {
    if (!empty($format->{$filter_id})) {
      $count++;
    }
  }
  $req = array(
    'title' => t('URL replace filter'),
  );
  if ($count) {
    $req['value'] = format_plural($count, "Used in 1 format.", "Used in @count formats.");
    $req['severity'] = REQUIREMENT_OK;
  }
  else {
    $req['value'] = t('Module is enabled but no format uses its filter. You should disable the module or use the filter in at least one format.');
    $req['severity'] = REQUIREMENT_INFO;
  }

  return array('url_replace_filter' => $req);
}

/**
 * Implementation of hook_disable().
 *
 * - Flush filter cache to remove content cached with this filter.
 */
function url_replace_filter_disabled() {
  cache_clear_all('*', 'cache_filter', TRUE);
}

/**
 * Implementation of hook_uninstall().
 *
 * - Remove all configuration variables for the module.
 * - Remove instances of the filter in all input formats.
 * - Flush filter cache to remove content cached with this filter.
 */
function url_replace_filter_uninstall() {
  // Delete configuration variables.
  foreach (array_keys($GLOBALS['conf']) as $name ) {
    if (strpos($name, 'url_replace_filter_') === 0) {
      variable_del($name);
    }
  }

  // Remove filter from input formats.
  $formats = _url_replace_filter_get_formats();
  foreach ($formats as $format) {
    db_query("DELETE FROM {filters} WHERE module = 'url_replace_filter'");
  }
  cache_clear_all('*', 'cache_filter', TRUE);
}