/**
* Truncate (html) string
*
* @see http://dodona.wordpress.com/2009/04/05/how-do-i-truncate-an-html-string-without-breaking-the-html-code/
*
* @param string $a_text
* @param int $a_length
* @param string $a_ending
* @param bool $a_exact
* @param bool $a_consider_html
* @return string
*/
public static function truncateHTML($a_text, $a_length = 100, $a_ending = '...', $a_exact = false, $a_consider_html = true)
{
include_once "Services/Utilities/classes/class.ilStr.php";
if ($a_consider_html) {
// if the plain text is shorter than the maximum length, return the whole text
if (strlen(preg_replace('/<.*?>/', '', $a_text)) <= $a_length) {
return $a_text;
}
// splits all html-tags to scanable lines
$total_length = strlen($a_ending);
$open_tags = array();
$truncate = '';
preg_match_all('/(<.+?>)?([^<>]*)/s', $a_text, $lines, PREG_SET_ORDER);
foreach ($lines as $line_matchings) {
// if there is any html-tag in this line, handle it and add it (uncounted) to the output
if (!empty($line_matchings[1])) {
// if it's an "empty element" with or without xhtml-conform closing slash
if (preg_match('/^<(\\s*.+?\\/\\s*|\\s*(img|br|input|hr|area|base|basefont|col|frame|isindex|link|meta|param)(\\s.+?)?)>$/is', $line_matchings[1])) {
// do nothing
} else {
if (preg_match('/^<\\s*\\/([^\\s]+?)\\s*>$/s', $line_matchings[1], $tag_matchings)) {
// delete tag from $open_tags list
$pos = array_search($tag_matchings[1], $open_tags);
if ($pos !== false) {
unset($open_tags[$pos]);
}
} else {
if (preg_match('/^<\\s*([^\\s>!]+).*?>$/s', $line_matchings[1], $tag_matchings)) {
// add tag to the beginning of $open_tags list
array_unshift($open_tags, strtolower($tag_matchings[1]));
}
}
}
// add html-tag to $truncate'd text
$truncate .= $line_matchings[1];
}
// calculate the length of the plain text part of the line; handle entities as one character
$content_length = strlen(preg_replace('/&[0-9a-z]{2,8};|&#[0-9]{1,7};|[0-9a-f]{1,6};/i', ' ', $line_matchings[2]));
if ($total_length + $content_length > $a_length) {
// the number of characters which are left
$left = $a_length - $total_length;
$entities_length = 0;
// search for html entities
if (preg_match_all('/&[0-9a-z]{2,8};|&#[0-9]{1,7};|[0-9a-f]{1,6};/i', $line_matchings[2], $entities, PREG_OFFSET_CAPTURE)) {
// calculate the real length of all entities in the legal range
foreach ($entities[0] as $entity) {
if ($entity[1] + 1 - $entities_length <= $left) {
$left--;
$entities_length += strlen($entity[0]);
} else {
// no more characters left
break;
}
}
}
// $truncate .= substr($line_matchings[2], 0, $left+$entities_length);
$truncate .= ilStr::shortenText($line_matchings[2], 0, $left + $entities_length);
// maximum lenght is reached, so get off the loop
break;
} else {
$truncate .= $line_matchings[2];
$total_length += $content_length;
}
// if the maximum length is reached, get off the loop
if ($total_length >= $a_length) {
break;
}
}
} else {
if (strlen($a_text) <= $a_length) {
return $a_text;
} else {
// $truncate = substr($a_text, 0, $a_length - strlen($a_ending));
$truncate = ilStr::shortenText($a_text, 0, $a_length - strlen($a_ending));
}
}
// THIS IS BUGGY AS IT MIGHT BREAK AN OPEN TAG AT THE END
if (!sizeof($open_tags)) {
// if the words shouldn't be cut in the middle...
if (!$a_exact) {
// ...search the last occurance of a space...
$spacepos = strrpos($truncate, ' ');
if ($spacepos !== false) {
// ...and cut the text in this position
// $truncate = substr($truncate, 0, $spacepos);
$truncate = ilStr::shortenText($truncate, 0, $spacepos);
}
}
}
// add the defined ending to the text
$truncate .= $a_ending;
if ($a_consider_html) {
// close all unclosed html-tags
foreach ($open_tags as $tag) {
$truncate .= '</' . $tag . '>';
}
}
return $truncate;
}
/**
* Shorten text depending on target encoding
* @param string $table
* @param string $field
* @param string $a_value
* @param int $a_size
* @return string
*/
protected function shortenText($table, $field, $a_value, $a_size)
{
global $ilLog;
if ($this->getTargetEncoding() == 'UTF-8') {
return $a_value;
}
// Convert to target encoding
$shortened = mb_convert_encoding($a_value, $this->getTargetEncoding(), 'UTF-8');
// Shorten
include_once './Services/Utilities/classes/class.ilStr.php';
$shortened = ilStr::shortenText($shortened, 0, $a_size, $this->getTargetEncoding());
// Convert back to UTF-8
$shortened = mb_convert_encoding($shortened, 'UTF-8', $this->getTargetEncoding());
if (strlen($a_value) != strlen($shortened)) {
$ilLog->write('Table : ' . $table);
$ilLog->write('Field : ' . $field);
$ilLog->write('Type : ' . $this->fields[$field]['type']);
$ilLog->write('Length : ' . $this->fields[$field]['length']);
$ilLog->write('Before : ' . $a_value);
$ilLog->write('Shortened : ' . $shortened);
$ilLog->write('Strlen Before: ' . strlen($a_value));
$ilLog->write('Strlen After : ' . strlen($shortened));
}
return $shortened;
}
