function _paging_body_shift in Paging 6

Helper function for automatic page separation by character limit.

1 call to _paging_body_shift()

_paging_nodeapi in ./paging.module

Helper function for paging_nodeapi().

File

./paging.module, line 687

Allows users to use a tag to break up a node into multiple pages.

Code

function _paging_body_shift($body, $size) {

  // If we have a short body, the entire body is the teaser.
  if (drupal_strlen($body) <= $size) {
    return $body;
  }

  // If the delimiter has not been specified, try to split at paragraph or
  // sentence boundaries.
  // The teaser may not be longer than maximum length specified. Initial slice.
  $teaser = truncate_utf8($body, $size);

  // Store the actual length of the UTF8 string -- which might not be the same
  // as $size.
  $max_rpos = drupal_strlen($teaser);

  // How much to cut off the end of the teaser so that it doesn't end in the
  // middle of a paragraph, sentence, or word.
  // Initialize it to maximum in order to find the minimum.
  $min_rpos = $max_rpos;

  // Store the reverse of the teaser.  We use strpos on the reversed needle and
  // haystack for speed and convenience.
  $reversed = strrev($teaser);

  // Build an array of arrays of break points grouped by preference.
  $break_points = array();

  // A paragraph near the end of sliced teaser is most preferable.
  $break_points[] = array(
    '</p>' => 0,
  );

  // If no complete paragraph then treat line breaks as paragraphs.
  $line_breaks = array(
    '<br />' => 6,
    '<br>' => 4,
  );

  // Newline only indicates a line break if line break converter
  // filter is present.
  if (isset($filters['filter/1'])) {
    $line_breaks["\n"] = 1;
  }
  $break_points[] = $line_breaks;

  // If the first paragraph is too long, split at the end of a sentence.
  $break_points[] = array(
    '. ' => 1,
    '! ' => 1,
    '? ' => 1,
    '。' => 0,
    '؟ ' => 1,
  );

  // Iterate over the groups of break points until a break point is found.
  foreach ($break_points as $points) {

    // Look for each break point, starting at the end of the teaser.
    foreach ($points as $point => $offset) {

      // The teaser is already reversed, but the break point isn't.
      $rpos = strpos($reversed, strrev($point));
      if ($rpos !== FALSE) {
        $min_rpos = min($rpos + $offset, $min_rpos);
      }
    }

    // If a break point was found in this group, slice and return the teaser.
    if ($min_rpos !== $max_rpos) {

      // Don't slice with length 0.  Length must be <0 to slice from RHS.
      return $min_rpos === 0 ? $teaser : drupal_substr($teaser, 0, 0 - $min_rpos);
    }
  }

  // If a break point was not found, still return a teaser.
  return $teaser;
}