<?php
/**
 * Plugin to implement cache interface forRedis
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @category  Cache
 * @package   PostActiv
 * @author    Moon Man <shitposterclub@gmail.com>
 * @copyright 2017 Shitposter Club
 * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
 * @link      https://shitposter.club/
 */


if (!defined('STATUSNET')) {
    exit(1);
}

class RedisCachePlugin extends Plugin
{
	static $cacheInitialized = false;

	private $_conn  = null;

	public $namespace = null;
        public $host = null;
        public $port = null;
	public $defaultExpiry = 86400; // 24hr

	function onInitializePlugin()
	{
		$this->_ensureConn();
		self::$cacheInitialized = true;
		return true;
	}

    function onStartCacheGet(&$key, &$value)
    {
        $this->_ensureConn();
        $value = $this->_conn->get($key);
        Event::handle('EndCacheGet', array($key, &$value));
        return false;
    }

    function onStartCacheSet(&$key, &$value, &$flag, &$expiry, &$success)
    {
        $this->_ensureConn();
        if ($expiry === null) {
            $expiry = $this->defaultExpiry;
        }
        $success = $this->_conn->set($key, $value, $expiry);
        Event::handle('EndCacheSet', array($key, $value, $flag,
                                           $expiry));
        return false;
    }

    function onStartCacheIncrement(&$key, &$step, &$value)
    {
        $this->_ensureConn();
        $value = $this->_conn->incrBy($key, $step);
        Event::handle('EndCacheIncrement', array($key, $step, $value));
        return false;
    }

    function onStartCacheDelete(&$key, &$success)
    {
        $this->_ensureConn();
        $success = $this->_conn->delete($key);
        Event::handle('EndCacheDelete', array($key));
        return false;
    }

    function onStartCacheReconnect(&$success)
    {
        // nothing to do
        return true;
    }

    private function _ensureConn()
    {
        if (empty($this->namespace)) {
            $this->namespace = common_config('site', 'nickname') . 'rcp:';
        }
        if (empty($this->_conn)) {
            $this->_conn = new Redis();
        }
        $this->_conn->pconnect($this->host, $this->port);
        $this->_conn->setOption(Redis::OPT_SERIALIZER, Redis::SERIALIZER_PHP);
        $this->_conn->setOption(Redis::OPT_PREFIX, $this->namespace);
    }

    protected function flag($flag)
    {
        //no flags are presently supported
        return $flag;
    }

    function onPluginVersion(array &$versions)
    {
        $versions[] = array('name' => 'Redis Cache',
                            'version' => '0.0.1',
                            'author' => 'MoonMan',
                            'homepage' => 'https://gitgud.io/ShitposterClub/RedisCache/',
                            'rawdescription' =>
                            _m('Use Redis to cache query results.'));
        return true;
    }
}