<?php

namespace addons\third\library;

use fast\Http;
use think\Config;
use think\Session;

/**
 * 微博
 */
class Wechat
{

    const GET_AUTH_CODE_URL = "https://open.weixin.qq.com/connect/oauth2/authorize";
    const GET_ACCESS_TOKEN_URL = "https://api.weixin.qq.com/sns/oauth2/access_token";
    const GET_USERINFO_URL = "https://api.weixin.qq.com/sns/userinfo";

    /**
     * 配置信息
     * @var array
     */
    private $config = [];

    public function __construct($options = [])
    {
        if ($config = Config::get('third.wechat'))
        {
            $this->config = array_merge($this->config, $config);
        }
        $this->config = array_merge($this->config, is_array($options) ? $options : []);
    }

    /**
     * 登陆
     */
    public function login()
    {
        header("Location:" . $this->getAuthorizeUrl());
    }

    /**
     * 获取authorize_url
     */
    public function getAuthorizeUrl()
    {
        $state = md5(uniqid(rand(), TRUE));
        Session::set('state', $state);
        $queryarr = array(
            "appid"        => $this->config['app_id'],
            "redirect_uri"  => $this->config['callback'],
            "response_type" => "code",
            "scope"         => $this->config['scope'],
            "state"         => $state,
        );
        request()->isMobile() && $queryarr['display'] = 'mobile';
        $url = self::GET_AUTH_CODE_URL . '?' . http_build_query($queryarr) . '#wechat_redirect';
        return $url;
    }

    /**
     * 获取用户信息
     * @param array $params
     * @return array
     */
    public function getUserInfo($params = [])
    {
        $params = $params ? $params : $_GET;
        if (isset($params['access_token']) || (isset($params['state']) && $params['state'] == Session::get('state') && isset($params['code'])))
        {
            //获取access_token
            $data = isset($params['code']) ? $this->getAccessToken($params['code']) : $params;
            $access_token = isset($data['access_token']) ? $data['access_token'] : '';
            $refresh_token = isset($data['refresh_token']) ? $data['refresh_token'] : '';
            $expires_in = isset($data['expires_in']) ? $data['expires_in'] : 0;
            if ($access_token)
            {
                $openid = isset($data['openid']) ? $data['openid'] : '';
                //获取用户信息
                $queryarr = [
                    "access_token" => $access_token,
                    "openid"       => $openid,
                    "lang"         => 'zh_CN'
                ];
                $ret = Http::post(self::GET_USERINFO_URL, $queryarr);
                $userinfo = json_decode($ret, TRUE);
                if (!$userinfo || isset($userinfo['errcode']))
                    return [];
                $userinfo = $userinfo ? $userinfo : [];
                $userinfo['avatar'] = isset($userinfo['headimgurl']) ? $userinfo['headimgurl'] : '';
                $data = [
                    'access_token'  => $access_token,
                    'refresh_token' => $refresh_token,
                    'expires_in'    => $expires_in,
                    'openid'        => $openid,
                    'userinfo'      => $userinfo
                ];
                return $data;
            }
        }
        return [];
    }

    /**
     * 获取access_token
     * @param string code
     * @return array
     */
    private function getAccessToken($code = '')
    {
        if (!$code)
            return '';
        $queryarr = array(
            "appid"      => $this->config['app_id'],
            "secret"     => $this->config['app_secret'],
            "code"       => $code,
            "grant_type" => "authorization_code",
        );
        $response = Http::post(self::GET_ACCESS_TOKEN_URL, $queryarr);
        $ret = json_decode($response, TRUE);
        return $ret ? $ret : [];
    }

}
