protected function sanitize($markdown)
{
$markdown = html_entity_decode($markdown, ENT_QUOTES, 'UTF-8');
$markdown = preg_replace('/<!DOCTYPE [^>]+>/', '', $markdown);
// Strip doctype declaration
$markdown = trim($markdown);
// Remove blank spaces at the beggining of the html
/*
* Removing unwanted tags. Tags should be added to the array in the order they are expected.
* XML, html and body opening tags should be in that order. Same case with closing tags
*/
$unwanted = array('<?xml encoding="UTF-8">', '<html>', '</html>', '<body>', '</body>', '<head>', '</head>', '
');
foreach ($unwanted as $tag) {
if (strpos($tag, '/') === false) {
// Opening tags
if (strpos($markdown, $tag) === 0) {
$markdown = substr($markdown, strlen($tag));
}
} else {
// Closing tags
if (strpos($markdown, $tag) === strlen($markdown) - strlen($tag)) {
$markdown = substr($markdown, 0, -strlen($tag));
}
}
}
$markdown = trim($markdown, "\n\r\v");
return $markdown;
}
