<?php
/**
 * Created by PhpStorm.
 * User: stanley-king
 * Date: 2017/6/20
 * Time: 上午10:25
 */

namespace thrid_author;

use Log;

class signaturer
{
    const appid = 'wx6b42e00ecaade538';
    const appsecret ='ee64233b3144d76217161666f8cb4c86';
    const access_token_url = "https://api.weixin.qq.com/cgi-bin/token";
    const ticket_url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket";

    const prefix = 'signaturer';

    private $mData;
    private static $stInstance = null;

    public static function instance()
    {
        if(self::$stInstance == null) {
            self::$stInstance = new signaturer();
        }
        return self::$stInstance;
    }

    private function __construct()
    {
        $this->mData = [];
    }

    public function signurl()
    {
        $ticket = $this->jsapi_ticket();
        if($ticket == false) {
            Log::record(__METHOD__ . " sign error",Log::ERR);
            return false;
        }

        $protocol = (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off' || $_SERVER['SERVER_PORT'] == 443) ? "https://" : "http://";
        $url = "$protocol$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";

        $timestamp = time();
        $nonceStr = $this->noncestr();
        $string = "jsapi_ticket={$ticket}&noncestr={$nonceStr}&timestamp={$timestamp}&url=$url";
        $signature = sha1($string);

        $sign = array(
            "appId"     => signaturer::appid,
            "nonceStr"  => $nonceStr,
            "timestamp" => $timestamp,
            "url"       => $url,
            "signature" => $signature,
            "rawString" => $string
        );
        return $sign;
    }

    private function noncestr($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 jsapi_ticket()
    {
        $ticket = $this->rjsapi_ticket();
        if($ticket == false)
        {
            $accessToken = $this->access_token();
            if($accessToken == false) {
                return false;
            }

            $params = ['type' => 'jsapi','access_token' => $accessToken];
            $res = http_request(self::ticket_url,$params);
            if($res == false) return false;

            $res = json_decode($res,true);
            if($res['errcode'] != 0) {
                Log::record("jsapi_ticket error : code={$res['errcode']} msg={$res['errmsg']}",Log::ERR);
                return false;
            }

            $ticket['expires'] = time() + intval($res['expires_in']) - 5;
            $ticket['ticket'] = $res['ticket'];

            wcache('jsapi_ticket',$ticket,self::prefix);
            $this->mData['jsapi_ticket'] = $ticket;
            $ticket = $ticket['ticket'];
        }

        return $ticket;
    }

    private function rjsapi_ticket()
    {
        if(empty($this->mData) || empty($this->mData['jsapi_ticket']))
        {
            $items = rcache('jsapi_ticket',self::prefix);
            if(empty($items)) {
                return false;
            } else {
                $this->mData['jsapi_ticket'] = $items;
            }
        }

        $expires = $this->mData['jsapi_ticket']['expires'];
        if(time() >= $expires) {
            return false;
        }

        return $this->mData['jsapi_ticket']['ticket'];
    }

    private function access_token()
    {
        $acctoken = $this->raccess_token();
        if($acctoken == false)
        {
            $params = ['grant_type' => 'client_credential','appid' => signaturer::appid,'secret' => signaturer::appsecret];
            $res = http_request(self::access_token_url,$params);
            if($res == false) return false;

            $res = json_decode($res,true);

            $token['expires'] = time() + intval($res['expires_in']) - 5;
            $token['token'] = $res['access_token'];

            wcache('access_token',$token,self::prefix);
            $this->mData['access_token'] = $token;
            $acctoken = $token['token'];
        }

        return $acctoken;
    }

    private function raccess_token()
    {
        if(empty($this->mData) || empty($this->mData['access_token']))
        {
            $token = rcache('access_token',self::prefix);
            if(empty($token)) {
                return false;
            } else {
                $this->mData['access_token'] = $token;
            }
        }

        $expires = $this->mData['access_token']['expires'];
        if(time() >= $expires) {
            return false;
        }

        return $this->mData['access_token']['token'];
    }
}