<?php

function getrandstr($length){
	 $str = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890';
	 $randStr = str_shuffle($str);//打乱字符串
	 $rands= substr($randStr,0,$length);//substr(string,start,length);返回字符串的一部分
	 return $rands;
}

/*
  示例C SSO
*/
class ClassC
{
    /**
     * 来源
     * @var string
     */
	protected $source_url;

	/**
     * 用户登录凭证
     * @var string
     */
	protected $userToken;

	/**
	 * 用户昵称
	 * @var string
	 */
	protected $username;

	/**
	 * redis
	 */
    protected $redis;

	/**
	 * 构造 获取存在用户信息
	 */
	public function __construct($redis)
	{
		$this->redis = $redis;
		$this->getCookie();
	}
    
    /**
     * [getCookie description]
     * @return [type] [description]
     */
	protected function getCookie()
	{
        $this->userToken = isset($_COOKIE['USERTOKEN']) ? $_COOKIE['USERTOKEN'] : '';
        $this->username = isset($_COOKIE['USERNAME']) ? $_COOKIE['USERNAME'] : '';
	}

    /**
     * 路由
     * @return
     */
    public function index()
    {
        if (empty($_GET['a'])) {
            exit('Empty Action');
        }

        $param = isset($_GET['c']) ? trim($_GET['c']) : '';
        $this->source_url = isset($_GET['d']) ? trim($_GET['d']) : '';

        $action = strtolower($_GET['a']);

        $this->$action($param);
    }
    
    /**
     * 登录页
     * @param  [type] $param [description]
     * @return [type]        [description]
     */
    public function login($param)
    {
        if($this->userToken && $this->username) {
        	if(empty($param)) {
	            echo '<span>用户'.$this->username.',你已经别的系统登录过了！</span></br><button type="button"><a href="http://a.cn/?token='.$this->userToken.'">返回A系统</a></button><button type="button"><a href="http://b.cn/?token='.$this->userToken.'">返回B系统</a></button>';
	            exit;
	        }
        } else {
        	if(empty($param)) {
	        	echo '你没有登录，如何登陆http://c.cn/?a=login&c=您的用户名称，即成功登陆';
	        	exit;
	        }
        } 

        $token = getrandstr(8);
        $username = $param;
 
        setcookie('USERTOKEN', $token, time() + 3600);
        setcookie('USERNAME', $username, time() + 3600);

        $this->setRedis($token, $username);

        echo '<span>用户'.$username.',登录成功！</span></br><button type="button"><a href="http://a.cn/?token='.$token.'">返回A系统</a></button><button type="button"><a href="http://b.cn/?token='.$token.'">返回B系统</a></button>';
    }
    
    /**
     * [setRedis description]
     * @param [type] $token    [description]
     * @param [type] $username [description]
     */
    protected function setRedis($token, $username)
    {
        $data = [];
    	$data['token']    = $token;
    	$data['username'] = $username;
        $this->redis->set($token, json_encode($data));
    }

    /**
     * 鉴权
     * @param  [type] $param [description]
     * @return [type]        [description]
     */
    protected function oauth($param)
    {
    	$redisParam = $this->redis->get($param);

        $oauth = (json_decode($redisParam)->token == $param) ? true : false;

        if(!$oauth) {
        	$this->output('5001', '错误Token');
        	exit;
        }

    	$data = [];
    	$data['token']    = $param;
    	$data['username'] = json_decode($redisParam)->username;
    	$this->output('200', 'ok', $data);
    }

    /**
     * 返回格式
     * @param  integer $errNo  [标识号]
     * @param  string  $errMsg [返回内容]
     * @param  array   $data   [返回数据]
     * @return [json]          
     */
    public function output($errNo = 200, $errMsg = 'ok', $data = array())
    {
        $res['errno'] = $errNo;
        $res['errMsg'] = $errMsg;
        $res['data'] = $data;
        echo json_encode($res);
    }
}

$redis = new Redis();
$redis->connect('127.0.0.1', 6379);
$redis->auth('199407');
$obj = new ClassC($redis);
$obj->index();