Замена формата цвета CSS в PHP

function hexToRgb($hex) 
{
	$hex = trim($hex, ' #');
 
	$size = strlen($hex);	
	if ($size == 3 || $size == 4) {
		$parts = str_split($hex, 1);
		$hex = '';
		foreach ($parts as $row) {
			$hex .= $row . $row;
		}		
	}
 
	$dec = hexdec($hex);
	$rgb = array();
	if ($size == 3 || $size == 6) {
		$rgb['red']   = 0xFF & ($dec >> 0x10);
		$rgb['green'] = 0xFF & ($dec >> 0x8);
		$rgb['blue']  = 0xFF & $dec;
		return 'rgb(' . implode(',', $rgb) . ')';
	} elseif ($size == 4 || $size == 8) {
		$rgb['red']   = 0xFF & ($dec >> 0x16);
		$rgb['green'] = 0xFF & ($dec >> 0x10);
		$rgb['blue']  = 0xFF & ($dec >> 0x8);
		$rgb['alpha'] = 0xFF & $dec;

		$rgb['alpha'] = round(($rgb['alpha'] / (255 / 100)) / 100, 2);
		return 'rgba(' . implode(',', $rgb) . ')';	
	} else {
		return false;
	}
	
	return $rgb;
}

function CssHexToRgb($css) 
{
	return preg_replace_callback(
		'/#(?:[0-9a-f]{3,8})/i', 
		function($matches){
			return hexToRgb($matches[0], true);
		}, 
		$css
	);
}


$css = '
	body {
		color: #000; 
		background: #4545;
	}
	header {
		color: #111111; 
		background: #00000080;
	}
';
 
echo CssHexToRgb($css);

exit();

function rgbToHex($color) 
{
	preg_match_all("/\((.+?)\)/", $color, $matches);
	if (!empty($matches[1][0])) {
		$rgb = explode(',', $matches[1][0]);
		$size = count($rgb);
		if ($size == 3 || $size == 4) {
			if ($size == 4) {
				$alpha = array_pop($rgb);
				$alpha = floatval(trim($alpha));
				$alpha = ceil(($alpha * (255 * 100)) / 100);
				array_push($rgb, $alpha);
			}
 
			$result = '#';
			foreach ($rgb as $row) {
				$result .= str_pad(dechex(trim($row)), 2, '0', STR_PAD_LEFT);
			}	
			
			return $result;
		}	
	}
 
	return false;
}


function CssRgbToHex($css) 
{
	return preg_replace_callback(
		'/((rgba)\((\d{1,3},\s?){3}(1|0?\.?\d+)\)|(rgb)\(\d{1,3}(,\s?\d{1,3}){2}\))/i', 
		function($matches){
			return rgbToHex($matches[0]);
		}, 
		$css
	);
}


$css = '
	body {
		color: rgb(0,0,0); 
		background: rgba(17,85,68,0.33);
	}
	header {
		color: rgb(17,17,17); 
		background: rgba(0,0,0,0.5);
	}
';

echo CssRgbToHex($css);