function _footnotes_replace_callback in Footnotes 6.2

Same name and namespace in other branches

1. 5.2 footnotes.module \_footnotes_replace_callback()
2. 5 footnotes.module \_footnotes_replace_callback()
3. 6 footnotes.module \_footnotes_replace_callback()
4. 7.3 footnotes.module \_footnotes_replace_callback()
5. 7.2 footnotes.module \_footnotes_replace_callback()

Helper function called from preg_replace_callback() above

Uses static vars to temporarily store footnotes found. In my understanding, this is not threadsafe?!

1 call to _footnotes_replace_callback()

footnotes_filter in ./footnotes.module

Implementation of hook_filter().

1 string reference to '_footnotes_replace_callback'

footnotes_filter in ./footnotes.module

Implementation of hook_filter().

File

./footnotes.module, line 267

The Footnotes module is a filter that can be used to insert automatically numbered footnotes into Drupal texts.

Code

function _footnotes_replace_callback($matches, $op = '') {
  static $opt_collapse = 0;
  static $n = 0;
  static $store_matches = array();
  static $used_values = array();
  $str = '';
  if ($op == 'prepare') {

    // In the 'prepare' case, the first argument contains the options to use.
    // The name 'matches' is incorrect, we just use the variable anyway.
    $opt_collapse = $matches;
    return 0;
  }
  if ($op == 'output footer') {
    if (count($store_matches) > 0) {

      // Only if there are stored fn matches, pass the array of fns to be themed
      // as a list
      $str = theme('footnote_list', $store_matches);
    }

    // Reset the static variables so they can be used again next time
    $n = 0;
    $store_matches = array();
    $used_values = array();
    return $str;
  }

  // Default op: act as called by preg_replace_callback()
  // Random string used to ensure footnote id's are unique, even
  // when contents of multiple nodes reside on same page. (fixes http://drupal.org/node/194558)
  $randstr = _footnotes_helper_randstr();
  $value = '';

  // Did the pattern match anything in the <fn> tag?
  if ($matches[1]) {

    // See if value attribute can parsed, either well-formed in quotes eg <fn value="3">
    if (preg_match('|value=["\'](.*?)["\']|', $matches[1], $value_match)) {
      $value = $value_match[1];

      // Or without quotes eg <fn value=8>
    }
    elseif (preg_match('|value=(\\S*)|', $matches[1], $value_match)) {
      $value = $value_match[1];
    }
  }
  if ($value) {

    // A value label was found. If it is numeric, record it in $n so further notes
    // can increment from there.
    // After adding support for multiple references to same footnote in the body (http://drupal.org/node/636808)
    // also must check that $n is monotonously increasing
    if (is_numeric($value) && $n < $value) {
      $n = $value;
    }
  }
  elseif ($opt_collapse and $value_existing = _footnotes_helper_find_footnote($matches[2], $store_matches)) {

    // An identical footnote already exists. Set value to the previously existing value.
    $value = $value_existing;
  }
  else {

    // No value label, either a plain <fn> or unparsable attributes. Increment the
    // footnote counter, set label equal to it.
    $n++;
    $value = $n;
  }

  // Remove illegal characters from $value so it can be used as an HTML id attribute.
  $value_id = preg_replace('|[^\\w\\-]|', '', $value);

  // Create a sanitized version of $text that is suitable for using as HTML attribute
  // value. (In particular, as the title attribute to the footnote link.)
  $allowed_tags = array();
  $text_clean = filter_xss($matches['2'], $allowed_tags);

  // HTML attribute cannot contain quotes
  $text_clean = str_replace('"', "&quot;", $text_clean);

  // Remove newlines. Browsers don't support them anyway and they'll confuse line break converter in filter.module
  $text_clean = str_replace("\n", " ", $text_clean);
  $text_clean = str_replace("\r", "", $text_clean);

  // Create a footnote item as an array.
  $fn = array(
    'value' => $value,
    'text' => $matches[2],
    'text_clean' => $text_clean,
    'fn_id' => 'footnote' . $value_id . '_' . $randstr,
    'ref_id' => 'footnoteref' . $value_id . '_' . $randstr,
  );

  // We now allow to repeat the footnote value label, in which case the link to the previously
  // existing footnote is returned. Content of the current footnote is ignored.
  // See http://drupal.org/node/636808
  if (!in_array($value, $used_values)) {

    // This is the normal case, add the footnote to $store_matches
    // Store the footnote item.
    array_push($store_matches, $fn);
    array_push($used_values, $value);
  }
  else {

    // A footnote with the same label already exists
    // Use the text and id from the first footnote with this value.
    // Any text in this footnote is discarded.
    $i = array_search($value, $used_values);
    $fn['text'] = $store_matches[$i]['text'];
    $fn['text_clean'] = $store_matches[$i]['text_clean'];
    $fn['fn_id'] = $store_matches[$i]['fn_id'];

    // Push the new ref_id into the first occurence of this footnote label
    // The stored footnote thus holds a list of ref_id's rather than just one id
    $ref_array = is_array($store_matches[$i]['ref_id']) ? $store_matches[$i]['ref_id'] : array(
      $store_matches[$i]['ref_id'],
    );
    array_push($ref_array, $fn['ref_id']);
    $store_matches[$i]['ref_id'] = $ref_array;
  }

  // Return the item themed into a footnote link.
  return theme('footnote_link', $fn);
}