drupal_module__url_replace_filter/url_replace_filter.module

<?php
/**
 * @file
 * URL replace filter module.
 *
 * @author David Lesieur
 * @author Frédéric G. MARAND <fgm@osinet.fr>
 *
 * @license Licensed under the General Public License version 2.0 or later.
 */

/**
 * Implements hook_filter().
 */
function url_replace_filter_filter($operation, $delta = 0, $format = -1, $text = '') {
  if (intval($delta) !== 0) {
    watchdog('url_replace_filter', '@function invoked with non-zero delta: @delta. This should never happen.', array(
      '@function' => __FUNCTION__,
      '@delta' => $delta,
    ), WATCHDOG_ERROR);
  }

  switch ($operation) {
    case 'list':
      return array(0 => t('URL Replace Filter'));

    case 'description':
      return t('Allows administrators to replace the base URL in &lt;img&gt; and &lt;a&gt; elements.');

    case 'settings':
      return _url_replace_filter_settings($format);

    case 'process':
      $text = _url_replace_filter_process($text, $format);
      return $text;

    default:
      return $text;
  }
}

/**
 * Filter the given text.
 */
function _url_replace_filter_process($text, $format) {
  $settings = _url_replace_filter_get_settings($format);
  foreach ($settings as $setting) {
    if ($setting['original']) {
      $pattern = '!((<a\s[^>]*href)|(<img\s[^>]*src))\s*=\s*"' . preg_quote($setting['original']) . '!iU';
      if (preg_match_all($pattern, $text, $matches)) {
        $replacement = str_replace('%baseurl', rtrim(base_path(), '/'), $setting['replacement']);
        foreach ($matches[0] as $key => $match) {
          $text = str_replace($match, $matches[1][$key] . '="' . $replacement, $text);
        }
      }
    }
  }
  return $text;
}

/**
 * Settings for the HTML filter.
 */
function _url_replace_filter_settings($format) {
  $empty = 0;
  $form['url_replace_filter_' . $format] = array(
    '#type' => 'fieldset',
    '#title' => t('URL Replace Filter'),
    '#collapsible' => TRUE,
    '#collapsed' => FALSE,
    '#theme' => 'url_replace_filter_settings_form',
    '#tree' => TRUE,
  );
  $form['#submit'][] = '_url_replace_filter_settings_form_submit';

  $settings = _url_replace_filter_get_settings($format);
  $index = 0;
  foreach ($settings as $index => $setting) {
    _url_replace_filter_row_form($form, $format, $index, $setting['original'], $setting['replacement']);
    if (!$setting['original']) {
      $empty++;
    }
  }
  // Append some empty fields.
  while ($empty < 3) {
    $index++;
    $empty++;
    _url_replace_filter_row_form($form, $format, $index, '', '');
  }
  return $form;
}

/**
 * Submit handler for _url_replace_filter_settings() form.
 *
 * Remove useless empty settings to keep variable as small as possible.
 */
function _url_replace_filter_settings_form_submit($form, &$form_state) {
  $format = $form_state['values']['format'];
  $format_id = 'url_replace_filter_' . $format;
  if (!isset($form_state['values'][$format_id])) {
    return;
  }

  // Remove empty sets.
  foreach ($form_state['values'][$format_id] as $key => $value) {
    if (empty($value['original']) && empty($value['replacement'])) {
      unset($form_state['values'][$format_id][$key]);
    }
  }

  if (empty($form_state['values'][$format_id])) {
    drupal_set_message(t('URL Replace filter configuration is empty : you could <a href="!edit">remove it</a> from this input format.', array(
      '!edit' => check_url(url('admin/settings/filters/1')),
      )), 'warning');
  }
}

/**
 * Helper to build rows in the table built by _url_replace_filter_settings().
 *
 * @param array $form
 *   The form array.
 * @param int $format
 *   The format index.
 * @param int $index
 *   The format index.
 * @param string $original
 *   The original value to be replaced.
 * @param string $replacement
 *   The replacement for the original value.
 */
function _url_replace_filter_row_form(array &$form, $format, $index, $original, $replacement) {
  $form['url_replace_filter_' . $format][$index]['original'] = array(
    '#type' => 'textfield',
    '#size' => 50,
    '#default_value' => $original,
  );
  $form['url_replace_filter_' . $format][$index]['replacement'] = array(
    '#type' => 'textfield',
    '#size' => 50,
    '#default_value' => $replacement,
  );
}

/**
 * Helper for _url_replace_filter_process().
 *
 * @param int $format
 *   The id of the format.
 *
 * @return mixed
 *   The replacement information for the format.
 */
function _url_replace_filter_get_settings($format) {
  return variable_get('url_replace_filter_' . $format, array(
    0 => array('original' => '', 'replacement' => ''),
  ));
}

/**
 * Return the list of input formats containing the URL Replace filter.
 *
 * @return array
 *   The list of input formats, keyed by format_id.
 */
function _url_replace_filter_get_formats() {
  $filter_id = 'url_replace_filter/0';
  $formats = filter_formats();

  $ret = array();
  foreach ($formats as $format_id => $format) {
    $format_filters = filter_list_format($format_id);
    $format->{$filter_id} = isset($format_filters[$filter_id]);
    $ret[$format_id] = $format;
  }

  return $ret;
}

/**
 * Theme for the filter settings form.
 *
 * @param array $form
 *   A form array.
 *
 * @return string
 *   The themed form.
 */
function theme_url_replace_filter_settings_form(array $form = array()) {
  $header = array(t('Original'), t('Replacement'));
  foreach (element_children($form) as $index) {
    $row = array();
    foreach (element_children($form[$index]) as $key) {
      $row[] = drupal_render($form[$index][$key]);
    }
    $rows[] = $row;
  }
  $output = '<p>' . t('This filter allows you to replace the base URL in &lt;img&gt; and &lt;a&gt; elements.') . '</p>';
  $output .= theme('table', $header, $rows);
  $output .= t("<p>Enter original base URLs and their replacements. Matching is case-insensitive. You may use %baseurl in the replacement string to insert your site's base URL (without the trailing slash).</p><p><strong>Warning</strong>: To avoid unexpected results, you must include trailing slashes in both the original and replacement strings.</p><p><strong>Warning</strong>: Replacements are executed in the order you give them. Place the most specific URLs first. For example, <em>http://example.com/somepath/</em> should be replaced before <em>http://example.com/</em>.</p><p>If you need more replacement rules, more fields will be added after saving the settings.</p>");
  $output .= drupal_render($form);
  return $output;
}

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Insert configuration links in modules page.
 */
function url_replace_filter_form_system_modules_alter(array &$form) {
  // No way to know what alternate themes do with this form, so play it safe.
  if (isset($form['#theme']) && $form['#theme'] != 'confirm_form' && $form['#theme'] != 'module_filter_system_modules') {
    return;
  }
  // Users without filter access can not access the module settings.
  if (!user_access('administer filters')) {
    return;
  }

  $machine_name = 'url_replace_filter';
  $human_name = $form['name'][$machine_name]['#value'];

  // Description might have been altered, so do not rely on its default value.
  $description = isset($form['description'][$machine_name]['#value'])
    ? $form['description'][$machine_name]['#value']
    : $human_name;

  $format_ids = _url_replace_filter_get_formats();
  $links_array = array();
  $filter_id = "$machine_name/0";
  foreach ($format_ids as $format_id => $format) {
    if ($format->{$filter_id}) {
      $text = '!link (present)';
      $link = l($format->name, "admin/settings/filters/$format_id/configure");
    }
    else {
      $text = '!link (absent)';
      $link = l($format->name, "admin/settings/filters/$format_id");
    }
    $links_array[$format_id] = t($text, array('!link' => $link));
  }
  $links = implode(', ', $links_array);
  $form['description'][$machine_name]['#value'] = $description . ' ' . t('(Configure in !urls)', array(
    '!urls' => $links,
  ));
}

/**
 * Implements hook_theme().
 */
function url_replace_filter_theme() {
  $ret = array(
    'url_replace_filter_settings_form' => array(
      'arguments' => array('form' => NULL),
    ),
  );

  return $ret;
}