Logger

<?php

class Logger
{
    private $logPath;
    private $files;

    public function __construct($relativeLogPath = '/logs', $files = 10)
    {
        if (class_exists('\Bitrix\Main\Application')) {
            $this->logPath = \Bitrix\Main\Application::getDocumentRoot() . $relativeLogPath;
        } elseif ($_SERVER['DOCUMENT_ROOT']) {
            $this->logPath = $_SERVER['DOCUMENT_ROOT'] . $relativeLogPath;
        } else {
            $this->logPath = __DIR__ . $relativeLogPath;
        }
        $this->files = $files;
    }

    public function write($dump, $file = 'info', $message = '')
    {
        if (!is_dir($this->logPath . '/')) {
            mkdir($this->logPath . '/');
        }
        $file = $this->logPath . '/' . $file . '.log';

        if (!is_string($dump)) {
            $dump = var_export($dump, true);
        }

        ignore_user_abort(true);
        if ($fp = @fopen($file, "ab")) {
            if (flock($fp, LOCK_EX)) {
                @fwrite($fp, "Date: " . date("Y-m-d H:i:s") . "\n");
                if ($message) {
                    @fwrite($fp, "Message: " . $message . "\n");
                }
                @fwrite($fp, "Dump: " . $dump . "\n");
                @fwrite($fp, str_repeat('-', 30) . "\n\n");
                @fflush($fp);
                @flock($fp, LOCK_UN);
                @fclose($fp);
            }
        }
        ignore_user_abort(false);

        // if filesize more than 10 Mb rotate it
        if (filesize($file) > 10485760) {
            $this->rotate($file);
        }
    }

    private function rotate($file)
    {
        $path = pathinfo($file);
        $rotate = implode('', array(
            $path['dirname'],
            '/',
            $path['filename'],
            '_',
            date('Y-m-d_H:i:s'),
            '.',
            $path['extension']
        ));

        copy($file, $rotate);
        $this->clean($file);

        $files = glob($path['dirname'] . '/' . $path['filename'] . "*" . ".log");

        if (0 === $this->files) {
            return;
        }

        if (count($files) > $this->files) {
            natsort($files);
            $files = array_reverse($files);
            foreach (array_slice($files, $this->files) as $log) {
                if (is_writable($log)) {
                    unlink($log);
                }
            }
        }
    }

    private function clean($file)
    {
        file_put_contents($file, '');
    }

}