<?php
/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * An Appender that automatically creates a new logfile each day.
 *
 * The file is rolled over once a day. That means, for each day a new file
 * is created. A formatted version of the date pattern is used as to create
 * the file name using the {@link PHP_MANUAL#sprintf} function.
 *
 * This appender uses a layout.
 *
 * ##Configurable parameters:##
 *
 * - **datePattern** - Format for the date in the file path, follows formatting
 *     rules used by the PHP date() function. Default value: "Ymd".
 * - **file** - Path to the target file. Should contain a %s which gets
 *     substituted by the date.
 * - **append** - If set to true, the appender will append to the file,
 *     otherwise the file contents will be overwritten. Defaults to true.
 *
 * @version $Revision: 1382274 $
 * @package log4php
 * @subpackage appenders
 * @license http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0
 * @link http://logging.apache.org/log4php/docs/appenders/daily-file.html Appender documentation
 */
class LoggerAppenderDailyFile extends LoggerAppenderFile {

    /**
     * The 'datePattern' parameter.
     * Determines how date will be formatted in file name.
     * @var string
     */
    protected $datePattern = "Ymd";

    /**
     * Current date which was used when opening a file.
     * Used to determine if a rollover is needed when the date changes.
     * @var string
     */
    protected $currentDate;

    /** Additional validation for the date pattern. */
    public function activateOptions() {
        parent::activateOptions();

        if (empty($this->datePattern)) {
            $this->warn("Required parameter 'datePattern' not set. Closing appender.");
            $this->closed = true;
            return;
        }
    }

    /**
     * Appends a logging event.
     *
     * If the target file changes because of passage of time (e.g. at midnight)
     * the current file is closed. A new file, with the new date, will be
     * opened by the write() method.
     */
    public function append(LoggerLoggingEvent $event) {
        $eventDate = $this->getDate($event->getTimestamp());

        // Initial setting of current date
        if (!isset($this->currentDate)) {
            $this->currentDate = $eventDate;
        } // Check if rollover is needed
        else if ($this->currentDate !== $eventDate) {
            $this->currentDate = $eventDate;

            // Close the file if it's open.
            // Note: $this->close() is not called here because it would set
            //       $this->closed to true and the appender would not recieve
            //       any more logging requests
            if (is_resource($this->fp)) {
                $this->write($this->layout->getFooter());
                fclose($this->fp);
            }
            $this->fp = null;
        }

        parent::append($event);
    }

    /** Renders the date using the configured <var>datePattern<var>. */
    protected function getDate($timestamp = null) {
        return date($this->datePattern, $timestamp);
    }

    /**
     * Determines target file. Replaces %s in file path with a date.
     */
    protected function getTargetFile() {
        return str_replace('%s', $this->currentDate, $this->file);
    }

    /**
     * Sets the 'datePattern' parameter.
     * @param string $datePattern
     */
    public function setDatePattern($datePattern) {
        $this->setString('datePattern', $datePattern);
    }

    /**
     * Returns the 'datePattern' parameter.
     * @return string
     */
    public function getDatePattern() {
        return $this->datePattern;
    }
}