public function calculateTimings($messages)
    {
        $timings = [];
        $stack = [];

        foreach ($messages as $i => $log) {
            list($token, $level, $category, $timestamp, $traces) = $log;
            $log[5] = $i;
            if ($level == Logger::LEVEL_PROFILE_BEGIN) {
                $stack[] = $log;
            } elseif ($level == Logger::LEVEL_PROFILE_END) {
                if (($last = array_pop($stack)) !== null && $last[0] === $token) {
                    $timings[$last[5]] = [
                        'info' => $last[0],
                        'category' => $last[2],
                        'timestamp' => $last[3],
                        'trace' => $last[4],
                        'level' => count($stack),
                        'duration' => $timestamp - $last[3],
                    ];
                }
            }
        }

        ksort($timings);

        return array_values($timings);
    }