Content::convertBodyHtmlToText

static function convertBodyHtmlToText($body)
{
	// remove tags
	$innerBody = preg_replace('/<(script|iframe|style)(.*?)>(.*?)(<\\/\\1.*?>)/is', '', $body);
	$body = $innerBody ?: $body;

	// get  inner html if exists
	$innerBody = trim(preg_replace('/(.*?]*>)(.*?)(<\/body>.*)/is', '$2', $body));
	$body = $innerBody ?: $body;

	// modify links to text version
	$body = preg_replace_callback(
		"/]*?>([^>]*?)<\\/a>/i",
		function ($matches)
		{
			return $matches[1];
		},
		$body
	);

	// change 
 to new line
	$body = preg_replace('/\/i', "\n", $body);

	// remove tags
	$body = strip_tags($body);

	// format text to the left side
	$lines = [];
	foreach (explode("\n", trim($body)) as $line)
	{
		$lines[] = trim($line);
	}

	// remove redundant new lines
	$body = preg_replace("/[\\n]{2,}/", " ", implode(" ", $lines));

	// remove redundant spaces
	$body = preg_replace("/[ \\t]{2,}/", " ", $body);

	// decode html-entities
	return html_entity_decode($body);
}