php cut html text maintaining html tags and support utf-8 character

function html_cut($text, $max_length){
  $tags   = array();
	$result = "";

	$is_open   = false;
	$grab_open = false;
	$is_close  = false;
	$in_double_quotes = false;
	$in_single_quotes = false;
	$tag = "";

	$i = 0;
	$stripped = 0;

	$stripped_text = strip_tags($text);

	while ($i < mb_strlen($text,'utf-8') && $stripped < mb_strlen($stripped_text,'utf-8') && $stripped < $max_length){
		$symbol = mb_substr($text,$i,1,'utf-8');
		$result .= $symbol;

		switch ($symbol){
			case '<':
				$is_open   = true;
				$grab_open = true;
				break;

			case '"':
				if ($in_double_quotes)
					$in_double_quotes = false;
				else
					$in_double_quotes = true;

				break;

			case "'":
				if ($in_single_quotes)
					$in_single_quotes = false;
				else
					$in_single_quotes = true;

				break;

			case '/':
				if ($is_open && !$in_double_quotes && !$in_single_quotes){
					$is_close  = true;
					$is_open   = false;
					$grab_open = false;
				}

				break;

			case ' ':
				if ($is_open)
					$grab_open = false;
				else
					$stripped++;

				break;

			case '>':
				if ($is_open){
					$is_open   = false;
					$grab_open = false;
					array_push($tags, $tag);
					$tag = "";
				}elseif($is_close){
					$is_close = false;
					array_pop($tags);
					$tag = "";
				}

				break;

			default:
				if ($grab_open || $is_close)
					$tag .= $symbol;

				if (!$is_open && !$is_close)
					$stripped++;
		}

		$i++;
	}

	while ($tags){
		if (($tag = array_pop($tags)) != 'br') {
			$result .= "</$tag>";
		}
	}

	return $result;
}