<?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.
 */

namespace Apache\Log4php\Layouts;

use Apache\Log4php\Helpers\PatternParser;
use Apache\Log4php\LoggerException;
use Apache\Log4php\LoggingEvent;

/**
 * A flexible layout configurable with a pattern string.
 *
 * Configurable parameters:
 *
 * * converionPattern - A string which controls the formatting of logging
 *   events. See docs for full specification.
 *
 * @license http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0
 */
class PatternLayout extends AbstractLayout
{
    /** Default conversion pattern */
    const DEFAULT_CONVERSION_PATTERN = '%date %-5level %logger %message%newline';

    /** Default conversion TTCC Pattern */
    const TTCC_CONVERSION_PATTERN = '%d [%t] %p %c %x - %m%n';

    /** The conversion pattern. */
    protected $pattern = self::DEFAULT_CONVERSION_PATTERN;

    /** Maps conversion keywords to the relevant converter (default implementation). */
    protected static $defaultConverterMap = array(
        'c' => 'LoggerConverter',
        'lo' => 'LoggerConverter',
        'logger' => 'LoggerConverter',

        'C' => 'ClassConverter',
        'class' => 'ClassConverter',

        'cookie' => 'CookieConverter',

        'd' => 'DateConverter',
        'date' => 'DateConverter',

        'e' => 'EnvironmentConverter',
        'env' => 'EnvironmentConverter',

        'ex' => 'ThrowableConverter',
        'exception' => 'ThrowableConverter',
        'throwable' => 'ThrowableConverter',

        'F' => 'FileConverter',
        'file' => 'FileConverter',

        'l' => 'LocationConverter',
        'location' => 'LocationConverter',

        'L' => 'LineConverter',
        'line' => 'LineConverter',

        'm' => 'MessageConverter',
        'msg' => 'MessageConverter',
        'message' => 'MessageConverter',

        'M' => 'MethodConverter',
        'method' => 'MethodConverter',

        'n' => 'NewLineConverter',
        'newline' => 'NewLineConverter',

        'p' => 'LevelConverter',
        'le' => 'LevelConverter',
        'level' => 'LevelConverter',

        'r' => 'RelativeConverter',
        'relative' => 'RelativeConverter',

        'req' => 'RequestConverter',
        'request' => 'RequestConverter',

        's' => 'ServerConverter',
        'server' => 'ServerConverter',

        'ses' => 'SessionConverter',
        'session' => 'SessionConverter',

        'sid' => 'SessionIdConverter',
        'sessionid' => 'SessionIdConverter',

        't' => 'ProcessConverter',
        'pid' => 'ProcessConverter',
        'process' => 'ProcessConverter',

        'x' => 'NdcConverter',
        'ndc' => 'NdcConverter',

        'X' => 'MdcConverter',
        'mdc' => 'MdcConverter',
    );

    /** Maps conversion keywords to the relevant converter. */
    protected $converterMap = array();

    /**
     * Head of a chain of Converters.
     * @var AbstractConverter
     */
    private $head;

    /** Returns the default converter map. */
    public static function getDefaultConverterMap()
    {
        return self::$defaultConverterMap;
    }

    /** Constructor. Initializes the converter map. */
    public function __construct()
    {
        $this->converterMap = self::$defaultConverterMap;
    }

    /**
     * Sets the conversionPattern option. This is the string which
     * controls formatting and consists of a mix of literal content and
     * conversion specifiers.
     * @param array $conversionPattern
     */
    public function setConversionPattern($conversionPattern)
    {
        $this->pattern = $conversionPattern;
    }

    /**
     * Processes the conversion pattern and creates a corresponding chain of
     * pattern converters which will be used to format logging events.
     */
    public function activateOptions()
    {
        if (!isset($this->pattern)) {
            throw new LoggerException("Mandatory parameter 'conversionPattern' is not set.");
        }

        $parser = new PatternParser($this->pattern, $this->converterMap);
        $this->head = $parser->parse();
    }

    /**
     * Produces a formatted string as specified by the conversion pattern.
     *
     * @param  LoggingEvent $event
     * @return string
     */
    public function format(LoggingEvent $event)
    {
        $sbuf = '';
        $converter = $this->head;
        while ($converter !== null) {
            $converter->format($sbuf, $event);
            $converter = $converter->next;
        }

        return $sbuf;
    }
}