<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2014 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------
namespace Think\Cache\Driver;

use Think\Cache;

/**
 * Apachenote缓存驱动
 */
class Apachenote extends Cache
{

    /**
     * 架构函数
     * @param array $options 缓存参数
     * @access public
     */
    public function __construct($options = array())
    {
        if (!empty($options)) {
            $this->options = $options;
        }
        if (empty($options)) {
            $options = array(
                'host'    => '127.0.0.1',
                'port'    => 1042,
                'timeout' => 10,
            );
        }
        $this->options           = $options;
        $this->options['prefix'] = isset($options['prefix']) ? $options['prefix'] : C('DATA_CACHE_PREFIX');
        $this->options['length'] = isset($options['length']) ? $options['length'] : 0;
        $this->handler           = null;
        $this->open();
    }

    /**
     * 读取缓存
     * @access public
     * @param string $name 缓存变量名
     * @return mixed
     */
    public function get($name)
    {
        $this->open();
        $name = $this->options['prefix'] . $name;
        $s    = 'F' . pack('N', strlen($name)) . $name;
        fwrite($this->handler, $s);

        for ($data = '';!feof($this->handler);) {
            $data .= fread($this->handler, 4096);
        }
        N('cache_read', 1);
        $this->close();
        return '' === $data ? '' : unserialize($data);
    }

    /**
     * 写入缓存
     * @access public
     * @param string $name 缓存变量名
     * @param mixed $value  存储数据
     * @return boolean
     */
    public function set($name, $value)
    {
        N('cache_write', 1);
        $this->open();
        $value = serialize($value);
        $name  = $this->options['prefix'] . $name;
        $s     = 'S' . pack('NN', strlen($name), strlen($value)) . $name . $value;

        fwrite($this->handler, $s);
        $ret = fgets($this->handler);
        $this->close();
        if ("OK\n" === $ret) {
            if ($this->options['length'] > 0) {
                // 记录缓存队列
                $this->queue($name);
            }
            return true;
        }
        return false;
    }

    /**
     * 删除缓存
     * @access public
     * @param string $name 缓存变量名
     * @return boolean
     */
    public function rm($name)
    {
        $this->open();
        $name = $this->options['prefix'] . $name;
        $s    = 'D' . pack('N', strlen($name)) . $name;
        fwrite($this->handler, $s);
        $ret = fgets($this->handler);
        $this->close();
        return "OK\n" === $ret;
    }

    /**
     * 关闭缓存
     * @access private
     */
    private function close()
    {
        fclose($this->handler);
        $this->handler = false;
    }

    /**
     * 打开缓存
     * @access private
     */
    private function open()
    {
        if (!is_resource($this->handler)) {
            $this->handler = fsockopen($this->options['host'], $this->options['port'], $_, $_, $this->options['timeout']);
        }
    }

}
