static function formatDiffAsHTML($before, $after, $mode = "w")
{
if (!self::diff($before, $after, $mode)) {
return false;
}
$html = '';
$td = count(self::$diff);
for ($d = 0; $d < $td; ++$d) {
$diff = self::$diff[$d];
switch ($diff['change']) {
case '=':
$html .= nl2br(htmlSpecialChars(substr($before, $diff['position'], $diff['length'])));
break;
case '-':
$html .= '<del class="diff">' . nl2br(htmlSpecialChars(substr($before, $diff['position'], $diff['length']))) . '</del>';
break;
case '+':
$html .= '<ins class="diff">' . nl2br(htmlSpecialChars(substr($after, $diff['position'], $diff['length']))) . '</ins>';
break;
default:
self::$error = $diff['change'] . ' is not an expected difference change type';
return false;
}
}
return self::$diff_html = self::purifyHTML($html);
}
