<?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.

 *

 * @package log4php

 */

/**

 * Returns a value from a superglobal array corresponding to the

 * given key.

 *

 * Option: the key to look up within the superglobal array

 *

 * Also, it is possible that a superglobal variable is not populated by PHP

 * because of the settings in the variables-order ini directive. In this case

 * the converter will return an empty value.

 *

 * @see http://php.net/manual/en/language.variables.superglobals.php

 * @see http://www.php.net/manual/en/ini.core.php#ini.variables-order

 *

 * @package log4php

 * @subpackage pattern

 * @version $Revision: 1326626 $

 * @since 2.3

 */

abstract class LoggerPatternConverterSuperglobal extends LoggerPatternConverter {

    /**

     * Name of the superglobal variable, to be defined by subclasses.

     * For example: "_SERVER" or "_ENV".

     */

    protected $name;

    protected $value = '';

    public function activateOptions() {

        // Read the key from options array

        if (isset($this->option) && $this->option !== '') {

            $key = $this->option;

        }

        /*

         * There is a bug in PHP which doesn't allow superglobals to be

         * accessed when their name is stored in a variable, e.g.:

         *

         * $name = '_SERVER';

         * $array = $$name;

         *

         * This code does not work when run from within a method (only when run

         * in global scope). But the following code does work:

         *

         * $name = '_SERVER';

         * global $$name;

         * $array = $$name;

         *

         * That's why global is used here.

         */

        global ${$this->name};

        // Check the given superglobal exists. It is possible that it is not initialized.

        if (!isset(${$this->name})) {

            $class = get_class($this);

            trigger_error("log4php: $class: Cannot find superglobal variable \${$this->name}.", E_USER_WARNING);

            return;

        }

        $source = ${$this->name};

        // When the key is set, display the matching value

        if (isset($key)) {

            if (isset($source[$key])) {

                $this->value = $source[$key];

            }

        } // When the key is not set, display all values

        else {

            $values = array();

            foreach ($source as $key => $value) {

                $values[] = "$key=$value";

            }

            $this->value = implode(', ', $values);

        }

    }

    public function convert(LoggerLoggingEvent $event) {

        return $this->value;

    }

}