<?php
namespace Q3i\T3Local\Core\Log\Writer;

/**
 * This file is part of the TYPO3 CMS project.
 *
 * It is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, either version 2
 * of the License, or any later version.
 *
 * For the full copyright and license information, please read the
 * LICENSE.txt file that was distributed with this source code.
 *
 * The TYPO3 project - inspiring people to share!
 */

use TYPO3\CMS\Core\Log\LogLevel;
use TYPO3\CMS\Core\Log\LogRecord;
use TYPO3\CMS\Core\Log\Writer\WriterInterface;

/**
 * Log writer that writes the log records into a file.
 * but only if during the request at least one error with severity level "error" and above ocurres
 * Inspired by symfonys/monologs fingers_crossed log handler
 *
 * @author Artur Cichosz <a.cichosz@q3i.de>
 */
class FingersCrossedFileWriter extends \TYPO3\CMS\Core\Log\Writer\FileWriter {

	private $recordBuffer = [];
	private $severityThresholdHit = FALSE;

	/**
	 * Writes the log record
	 * but only if during the request at leas tone error with severity level "error" and above ocurres
	 *
	 * @param LogRecord $record Log record
	 * @return WriterInterface $this
	 * @throws \RuntimeException
	 */
	public function writeLog(LogRecord $record) {

		// force at least LogLevel::ERROR otherwise accept higher levels set with $GLOBALS["TYPO3_CONF_VARS"]['SYS']['systemLogLevel']
		$logLevelThreshold = $GLOBALS["TYPO3_CONF_VARS"]['SYS']['systemLogLevel'] < LogLevel::ERROR ? LogLevel::ERROR : $GLOBALS["TYPO3_CONF_VARS"]['SYS']['systemLogLevel'];

		if ($this->severityThresholdHit) {
			// write the record immediately, because the severity threshold has benn hit at least once
			// during this request
			parent::writeLog($record);
		} else if ($record->getLevel() <= $logLevelThreshold) {
			// severity level threshold hit, write all stored messages until the point the error
			// happend and all after
			$this->severityThresholdHit = TRUE;
			$this->recordBuffer[] = $record;
			foreach ($this->recordBuffer as $bufRecord) {
				parent::writeLog($bufRecord);
			}
			$this->recordBuffer = [];
		} else {
			// do not write immediately but store in memory
			$this->recordBuffer[] = $record;
		}

		return $this;
	}

}