pictcode

<?php

/**

 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)

 * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)

 *

 * Licensed under The MIT License

 * For full copyright and license information, please see the LICENSE.txt

 * Redistributions of files must retain the above copyright notice.

 *

 * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)

 * @link          http://cakephp.org CakePHP(tm) Project

 * @package       Cake.Cache

 * @since         CakePHP(tm) v 1.2.0.4933

 * @license       http://www.opensource.org/licenses/mit-license.php MIT License

 */

/**

 * Storage engine for CakePHP caching

 *

 * @package       Cake.Cache

 */

abstract class CacheEngine {

/**

 * Settings of current engine instance

 *

 * @var array

 */

        public $settings = array();

/**

 * Contains the compiled string with all groups

 * prefixes to be prepended to every key in this cache engine

 *

 * @var string

 */

        protected $_groupPrefix = null;

/**

 * Initialize the cache engine

 *

 * Called automatically by the cache frontend

 *

 * @param array $settings Associative array of parameters for the engine

 * @return bool True if the engine has been successfully initialized, false if not

 */

        public function init($settings = array()) {

                $settings += $this->settings + array(

                        'prefix' => 'cake_',

                        'duration' => 3600,

                        'probability' => 100,

                        'groups' => array()

                );

                $this->settings = $settings;

                if (!empty($this->settings['groups'])) {

                        sort($this->settings['groups']);

                        $this->_groupPrefix = str_repeat('%s_', count($this->settings['groups']));

                }

                if (!is_numeric($this->settings['duration'])) {

                        $this->settings['duration'] = strtotime($this->settings['duration']) - time();

                }

                return true;

        }

/**

 * Garbage collection

 *

 * Permanently remove all expired and deleted data

 *

 * @param int $expires [optional] An expires timestamp, invalidating all data before.

 * @return void

 */

        public function gc($expires = null) {

        }

/**

 * Write value for a key into cache

 *

 * @param string $key Identifier for the data

 * @param mixed $value Data to be cached

 * @param int $duration How long to cache for.

 * @return bool True if the data was successfully cached, false on failure

 */

        abstract public function write($key, $value, $duration);

/**

 * Read a key from the cache

 *

 * @param string $key Identifier for the data

 * @return mixed The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it

 */

        abstract public function read($key);

/**

 * Increment a number under the key and return incremented value

 *

 * @param string $key Identifier for the data

 * @param int $offset How much to add

 * @return New incremented value, false otherwise

 */

        abstract public function increment($key, $offset = 1);

/**

 * Decrement a number under the key and return decremented value

 *

 * @param string $key Identifier for the data

 * @param int $offset How much to subtract

 * @return New incremented value, false otherwise

 */

        abstract public function decrement($key, $offset = 1);

/**

 * Delete a key from the cache

 *

 * @param string $key Identifier for the data

 * @return bool True if the value was successfully deleted, false if it didn't exist or couldn't be removed

 */

        abstract public function delete($key);

/**

 * Delete all keys from the cache

 *

 * @param bool $check if true will check expiration, otherwise delete all

 * @return bool True if the cache was successfully cleared, false otherwise

 */

        abstract public function clear($check);

/**

 * Clears all values belonging to a group. Is up to the implementing engine

 * to decide whether actually delete the keys or just simulate it to achieve

 * the same result.

 *

 * @param string $group name of the group to be cleared

 * @return bool

 */

        public function clearGroup($group) {

                return false;

        }

/**

 * Does whatever initialization for each group is required

 * and returns the `group value` for each of them, this is

 * the token representing each group in the cache key

 *

 * @return array

 */

        public function groups() {

                return $this->settings['groups'];

        }

/**

 * Cache Engine settings

 *

 * @return array settings

 */

        public function settings() {

                return $this->settings;

        }

/**

 * Generates a safe key for use with cache engine storage engines.

 *

 * @param string $key the key passed over

 * @return mixed string $key or false

 */

        public function key($key) {

                if (empty($key)) {

                        return false;

                }

                $prefix = '';

                if (!empty($this->_groupPrefix)) {

                        $prefix = vsprintf($this->_groupPrefix, $this->groups());

                }

                $key = preg_replace('/[\s]+/', '_', strtolower(trim(str_replace(array(DS, '/', '.'), '_', strval($key)))));

                return $prefix . $key;

        }

}