package platform

import (
	"SciencesServer/utils"
	"errors"
)

type Wechat struct {
	AppID, AppSecret string
}

type WechatHandle func(appID, appSecret string) *Wechat

type (
	WechatErrorResponse struct {
		ErrCode int    `json:"errcode"`
		ErrMsg  string `json:"errmsg"`
	}
	// WechatAccessTokenRequest 请求AccessToken参数
	WechatAccessTokenRequest struct {
		Code string
	}
	// WechatAccessTokenResponse 获取AccessToken响应参数
	WechatAccessTokenResponse struct {
		AccessToken  string `json:"access_token"`
		ExpiresIn    int    `json:"expires_in"`
		RefreshToken string `json:"refresh_token"`
		OpenID       string `json:"openid"`
		Scope        string `json:"scope"`
		UnionID      string `json:"unionid"`
		WechatErrorResponse
	}
)

const (
	// WechatAccessTokenUrl AccessToken访问地址
	WechatAccessTokenUrl string = "https://api.weixin.qq.com/sns/oauth2/access_token"
)

func (this *Wechat) ScanLogin() {

}

func (this *Wechat) ScanPay() {

}

// AccessToken AccessToken操作
func (this *Wechat) AccessToken(req *WechatAccessTokenRequest) (*WechatAccessTokenResponse, error) {
	params := map[string]interface{}{
		"appid": this.AppID, "secret": this.AppSecret, "code": req.Code, "grant_type": "authorization_code",
	}
	resp, err := utils.NewClient(WechatAccessTokenUrl, utils.MethodForGet, params).Request(utils.RequestBodyFormatForXWWWFormUrlencoded)

	if err != nil {
		return nil, err
	}
	out := new(WechatAccessTokenResponse)

	if err = utils.FromJSONBytes(resp, out); err != nil {
		return nil, err
	}
	if out.WechatErrorResponse.ErrCode != 0 {
		return nil, errors.New(out.WechatErrorResponse.ErrMsg)
	}
	return out, nil
}

func NewWechat() WechatHandle {
	return func(appID, appSecret string) *Wechat {
		return &Wechat{AppID: appID, AppSecret: appSecret}
	}
}