<?php
/**
 * App优化JSSDK
 */

namespace Util\Wx;
class Jssdk
{
    private $appid;
    private $token;//access_token
    private $url;

    public function __construct($options)
    {
        $this->appid = isset($options['appid']) ? $options['appid'] : '';
        $this->token = isset($options['token']) ? $options['token'] : '';
        $this->url = isset($options['url']) ? $options['url'] : '';
    }

    public function getSignPackage()
    {
        $appid = $this->appid;
        $token = $this->token;
        $url = $this->url;
        if (!$appid || !$token || !$url) {
            return FALSE;
        }
        //处理超链接#
        $ret = strpos($url, '#');
        if ($ret) {
            $url = substr($url, 0, $ret);
        }
        $url = trim($url);
        $jsapiTicket = $this->getJsApiTicket($token);
        $timestamp = time();
        $nonceStr = $this->createNonceStr();

        // 这里参数的顺序要按照 key 值 ASCII 码升序排序
        $string = "jsapi_ticket=$jsapiTicket&noncestr=$nonceStr&timestamp=$timestamp&url=$url";

        $signature = sha1($string);

        $signPackage = array(
            "appId" => $appid,
            "nonceStr" => $nonceStr,
            "timestamp" => $timestamp,
            "url" => $url,
            "signature" => $signature,
            "rawString" => $string
        );

        return $signPackage;
    }

    private function createNonceStr($length = 16)
    {
        $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
        $str = "";
        for ($i = 0; $i < $length; $i++) {
            $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
        }
        return $str;
    }

    private function getJsApiTicket($accessToken)
    {
        // jsapi_ticket 应该全局存储与更新，以下代码以写入到文件中做示例
        $data = json_decode(file_get_contents("./Data/jsapi_ticket.json"));
        //dump($data);
        if ($data->expire_time < time()) {
            // $accessToken = $this->getAccessToken();
            $url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&access_token=$accessToken";
            $res = json_decode($this->http_get($url));
            //dump($res);
            $ticket = $res->ticket;
            if ($ticket) {
                $data->expire_time = time() + 7000;
                $data->jsapi_ticket = $ticket;
                file_put_contents("./Data/jsapi_ticket.json", json_encode($data));
                //$fp = fopen("./Data/jsapi_ticket.json", "w");
                //fwrite($fp, json_encode($data));
                //fclose($fp);
            } else {
                die('no ticket!');
            }
        } else {
            $ticket = $data->jsapi_ticket;
        }

        return $ticket;
    }

    /**
     * GET 请求
     * @param string $url
     */
    private function http_get($url)
    {
        $oCurl = curl_init();
        if (stripos($url, "https://") !== FALSE) {
            curl_setopt($oCurl, CURLOPT_SSL_VERIFYPEER, FALSE);
            curl_setopt($oCurl, CURLOPT_SSL_VERIFYHOST, FALSE);
            curl_setopt($oCurl, CURLOPT_SSLVERSION, 1); //CURL_SSLVERSION_TLSv1
        }
        curl_setopt($oCurl, CURLOPT_URL, $url);
        curl_setopt($oCurl, CURLOPT_RETURNTRANSFER, 1);
        $sContent = curl_exec($oCurl);
        $aStatus = curl_getinfo($oCurl);
        curl_close($oCurl);
        if (intval($aStatus["http_code"]) == 200) {
            return $sContent;
        } else {
            return false;
        }
    }

}