<?php

/**
 * Memcached缓存驱动
 */

namespace base\cache;

class MemcachedDriver implements CacheInterface{
    protected $mmc = NULL;
    protected $group = '';
    protected $ver = 0;

    public function __construct($config = array()) {
        $this->mmc = new \Memcached;

        if(empty($config)) {
            $config['MEM_SERVER'] = array(array('127.0.0.1', 11211));
            $config['MEM_GROUP'] = '';
            $config['MEM_OPTIONS'] = NULL;
            $config['USERNAME'] = '';
            $config['PASSWORD'] = '';
        }

        foreach($config['MEM_SERVER'] as $v) {
            call_user_func_array(array($this->mmc, 'addServer'), $v);
        }
        if(isset($config['MEM_OPTIONS'])){
            $this->mmc->setOptions($config['MEM_OPTIONS']);
        }
        if(isset($config['USERNAME']) && !empty($config['USERNAME'])){
            $this->mmc->setSaslAuthData($config['USERNAME'], $config['PASSWORD']);
        }

        if( isset($config['MEM_GROUP']) ){
            $this->group = $config['MEM_GROUP'];
        }
        $this->ver = intval( $this->mmc->get($this->group.'_ver') );
    }

    public function get($key) {
        return $this->mmc->get($this->group.'_'.$this->ver.'_'.$key);
    }

    public function set($key, $value, $expire = 1800) {
        return $this->mmc->set($this->group.'_'.$this->ver.'_'.$key, $value, $expire);
    }

    public function inc($key, $value = 1) {
        return $this->mmc->increment($this->group.'_'.$this->ver.'_'.$key, $value);
    }

    /**
     * 更新缓存
     * @access public
     * @param string $name 缓存变量名
     * @param mixed $value  存储数据
     * @param integer $expire  有效时间（秒）
     * @return boolean
     */
    public function replace($key, $value, $expire = 1800)
    {
        if ($this->mmc->replace($this->group.'_'.$this->ver.'_'.$key, $value, time() + $expire)) {
            return true;

        }
        return false;

    }

    public function des($key, $value = 1) {
        return $this->mmc->decrement($this->group.'_'.$this->ver.'_'.$key, $value);
    }

    public function del($key) {
        return $this->mmc->delete($this->group.'_'.$this->ver.'_'.$key);
    }

    public function clear() {
        return  $this->mmc->set($this->group.'_ver', $this->ver+1);
    }
}