views_natural_sort.module in Views Natural Sort 6

Provides a views filter that sorts titles by a more natural manner by ignoring articles like "The" and "A."

Normal sort: A Chorus Line All American Fiddler on the Roof Oklahoma! The King And I

Natural sort: All American A Chorus Line Fiddler on the Roof The King And I Oklahoma!

File

views_natural_sort.module

<?php

/**
 * @file
 * Provides a views filter that sorts titles by a more natural manner by
 * ignoring articles like "The" and "A."
 *
 * Normal sort:
 * A Chorus Line
 * All American
 * Fiddler on the Roof
 * Oklahoma!
 * The King And I
 *
 * Natural sort:
 * All American
 * A Chorus Line
 * Fiddler on the Roof
 * The King And I
 * Oklahoma!
 */

/**
 * Implementation of hook_menu().
 */
function views_natural_sort_menu() {
  $items = array();
  $items['admin/settings/views_natural_sort'] = array(
    'title' => 'Views Natural Sort',
    'description' => 'Configuration and settings for natural sorting.',
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array(
      'administer site configuration',
    ),
    'file' => 'system.admin.inc',
    'file path' => drupal_get_path('module', 'system'),
    'type' => MENU_NORMAL_ITEM,
  );
  $items['admin/settings/views_natural_sort/rebuild_index'] = array(
    'title' => 'Rebuild Search Index',
    'description' => 'Rebuild Views Natural Sort\'s search index',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'views_natural_sort_rebuild_index_form',
    ),
    'access callback' => 'user_access',
    'access arguments' => array(
      'administer views',
    ),
    'file' => 'views_natural_sort.admin.inc',
    'type' => MENU_NORMAL_ITEM,
  );
  $items['admin/settings/views_natural_sort/settings'] = array(
    'title' => 'Configure Word Removal Lists',
    'description' => 'Set what words should be ignored when performing a natural sort.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'views_natural_sort_settings_form',
    ),
    'access callback' => 'user_access',
    'access arguments' => array(
      'administer views',
    ),
    'file' => 'views_natural_sort.admin.inc',
    'type' => MENU_NORMAL_ITEM,
  );
  return $items;
}

/**
 * Implementation of hook_views_api().
 */
function views_natural_sort_views_api() {
  return array(
    'api' => 2.0,
  );
}

/**
 * Implementation of hook_nodeapi().
 *
 * This keeps our natural sort index up to date.
 */
function views_natural_sort_nodeapi(&$node, $op) {

  //
  switch ($op) {
    case 'update':
    case 'insert':
      _views_natural_sort_store_node($node);
      break;
    case 'delete':
      _views_natural_sort_remove_node($node);
  }
}

/**
 * Helper function for writing node data to our sort index.
 *
 * @param $node
 * A drupal node object containing at least a nid and title.
 */
function _views_natural_sort_store_node($node) {
  $record = new stdClass();
  $record->nid = $node->nid;
  $record->field = 'title';
  $record->content = views_natural_sort_encode($node->title);

  // Try to update. On fail, try inserting.
  $exists = db_result(db_query("SELECT 1 FROM {views_natural_sort} WHERE nid = %d AND field = '%s'", array(
    $record->nid,
    $record->field,
  )));
  if ($exists) {
    $return = drupal_write_record('views_natural_sort', $record, array(
      'nid',
      'field',
    ));
  }
  else {
    $return = drupal_write_record('views_natural_sort', $record);
  }
  return $return;
}

/**
 * _views_natural_sort_remove_node
 *
 * @param $node
 * A drupal node object containing at least a nid.
 */
function _views_natural_sort_remove_node($node) {
  db_query('DELETE FROM {views_natural_sort} WHERE nid = %d', $node->nid);
}

/**
 * Encodes a string into an ascii-sortable such:
 *  - Leading articles in common languages are ingored: The A An El La Le Il
 *  - Unimportant punctuation is ignored: # ' " ( )
 *  - Unimportant words are ignored: and of or
 *  - Embeded numbers will sort in numerical order. The following possiblities
 *    are supported
 *    - A leading dash indicates a negative number, unless it is preceded by a
 *      non-whitespace character, which case it is considered just a dash.
 *    - Leading zeros are properly ignored so as to not influence sort order
 *    - Decimal numbers are supported using a period as the decimal character
 *    - Thousands separates are ignored, using the comma as the thous. character
 *    - Numbers may be up to 99 digits before the decimal, up to the precision
 *      of the processor.
 *
 * @param $string string
 *   The string to be encoded
 *
 * @return string
 *   The encoded string
 */
function views_natural_sort_encode($string) {
  $words = variable_get('views_natural_sort_words_remove', array());
  $beginning_words = variable_get('views_natural_sort_beginning_words_remove', array());
  $symbols = variable_get('views_natural_sort_symbols_remove', '');

  // Get the words ready for being put in a regex.
  array_walk($beginning_words, 'preg_quote');
  array_walk($words, 'preg_quote');
  $regex = array();
  $replace = array();

  // Remove words from the beginning only!
  if (!empty($beginning_words)) {
    $regex[] = '/^(' . implode('|', $beginning_words) . ')\\s+/i';
    $replace[] = '';
  }

  // Remove words reguardless where they are as long as they are a word.
  if (!empty($words)) {
    $regex[] = '/\\s(' . implode('|', $words) . ')\\s+/i';
    $replace[] = ' ';
    $regex[] = '/^(' . implode('|', $words) . ')\\s+/i';
    $replace[] = '';
  }

  // Remove symbols.
  if (strlen($symbols) != 0) {
    $regex[] = '/[' . preg_quote($symbols) . ']/';
    $replace[] = '';
  }
  if (!empty($regex) && !empty($replace)) {
    $string = preg_replace($regex, $replace, $string);
  }

  // Find an optional leading dash (either preceded by whitespace or the first character) followed
  // by either:
  //   - an optional series of digits (with optional imbedded commas), then a period, then an optional series of digits OR
  //   - a series of digits (with optional imbedded commas)
  $string = preg_replace_callback('/(\\s-|^-)?(?:(\\d[\\d,]*)?\\.(\\d+)|(\\d[\\d,]*))/', '_views_natural_sort_number_encode_match_callback', $string);
  return $string;
}

/**
 * Encodes a string representing numbers into a special format that can be sorted alphanumerically.
 *
 * @param array $match
 *   array of matches passed from preg_replace_callback
 *   $match[0] is the entire matching string
 *   $match[1] if present, is the optional dash, preceded by optional whitespace
 *   $match[2] if present, is whole number portion of the decimal number
 *   $match[3] if present, is the fractional portion of the decimal number
 *   $match[4] if present, is the integer (when no fraction is matched)
 *
 * @return string
 *   String representing a numerical value that will sort numerically in an
 *   alphanumeric search.
 */
function _views_natural_sort_number_encode_match_callback($match) {

  // Remove commas and leading zeros from whole number
  $whole = (string) (int) str_replace(',', '', isset($match[4]) && strlen($match[4]) > 0 ? $match[4] : $match[2]);

  // Remove traililng 0's from fraction, then add the decimal and one trailing 0
  $fraction = trim('.' . $match[3], '0') . '0';
  $encode = sprintf('%02u', strlen($whole)) . $whole . $fraction;
  if (strlen($match[1])) {

    // Negative number. Make 10's complement. Put back any leading white space and the dash
    // Requires intermediate to avoid double-replacing the same digit. str_replace seems to
    // work by copying the source to the result, then successively replacing within it,
    // rather than replacing from the source to the result.
    $digits = array(
      '0',
      '1',
      '2',
      '3',
      '4',
      '5',
      '6',
      '7',
      '8',
      '9',
    );
    $intermediate = array(
      'a',
      'b',
      'c',
      'd',
      'e',
      'f',
      'g',
      'h',
      'i',
      'j',
    );
    $rev_digits = array(
      '9',
      '8',
      '7',
      '6',
      '5',
      '4',
      '3',
      '2',
      '1',
      '0',
    );
    $encode = $match[1] . str_replace($intermediate, $rev_digits, str_replace($digits, $intermediate, $encode));
  }
  return $encode;
}

Functions

Name	Description
views_natural_sort_encode	Encodes a string into an ascii-sortable such:
views_natural_sort_menu	Implementation of hook_menu().
views_natural_sort_nodeapi	Implementation of hook_nodeapi().
views_natural_sort_views_api	Implementation of hook_views_api().
_views_natural_sort_number_encode_match_callback	Encodes a string representing numbers into a special format that can be sorted alphanumerically.
_views_natural_sort_remove_node	_views_natural_sort_remove_node
_views_natural_sort_store_node	Helper function for writing node data to our sort index.