package user

import (
	"context"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"net/url"
	"time"
	"tyc-server/app/main/api/internal/svc"
	"tyc-server/app/main/api/internal/types"
	"tyc-server/app/main/model"
	jwtx "tyc-server/common/jwt"
	"tyc-server/common/xerr"

	"github.com/pkg/errors"
	"github.com/zeromicro/go-zero/core/stores/sqlx"

	"github.com/zeromicro/go-zero/core/logx"
)

type WxMiniAuthLogic struct {
	logx.Logger
	ctx    context.Context
	svcCtx *svc.ServiceContext
}

func NewWxMiniAuthLogic(ctx context.Context, svcCtx *svc.ServiceContext) *WxMiniAuthLogic {
	return &WxMiniAuthLogic{
		Logger: logx.WithContext(ctx),
		ctx:    ctx,
		svcCtx: svcCtx,
	}
}

func (l *WxMiniAuthLogic) WxMiniAuth(req *types.WXMiniAuthReq) (resp *types.WXMiniAuthResp, err error) {
	// 1. 使用微信提供的 code 换取 session_key 和 openid
	weChatResponse, err := l.exchangeCodeForSession(req.Code)
	if err != nil {
		return nil, errors.Wrapf(xerr.NewErrMsg("微信登录失败"), "微信登录, code 换取 session 失败: %s, err: %+v", req.Code, err)
	}

	// 2. 根据 openid 查找用户
	userAuth, findErr := l.svcCtx.UserAuthModel.FindOneByAuthTypeAuthKey(l.ctx, model.UserAuthTypeWxMini, weChatResponse.OpenId)
	if findErr != nil && findErr != model.ErrNotFound {
		return nil, errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "微信登录, 读取用户认证信息失败, openid: %s, err: %+v", weChatResponse.OpenId, findErr)
	}

	var user *model.User
	if findErr == model.ErrNotFound {
		// 用户不存在，创建新用户
		user = &model.User{}
		user.Mobile = weChatResponse.OpenId
		if transErr := l.svcCtx.UserModel.Trans(l.ctx, func(ctx context.Context, session sqlx.Session) error {
			// 插入新用户
			insertResult, userInsertErr := l.svcCtx.UserModel.Insert(ctx, session, user)
			if userInsertErr != nil {
				return errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "微信登录, 数据库插入新用户失败, openid: %s, err: %+v", weChatResponse.OpenId, userInsertErr)
			}

			// 获取新用户的 ID
			lastId, lastInsertIdErr := insertResult.LastInsertId()
			if lastInsertIdErr != nil {
				return errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "微信登录, 获取新用户ID失败, err:%+v, user:%+v", lastInsertIdErr, user)
			}
			user.Id = lastId

			// 创建用户认证信息
			newUserAuth := &model.UserAuth{
				UserId:   lastId,
				AuthKey:  weChatResponse.OpenId,
				AuthType: model.UserAuthTypeWxMini,
			}
			if _, userAuthInsertErr := l.svcCtx.UserAuthModel.Insert(ctx, session, newUserAuth); userAuthInsertErr != nil {
				return errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "微信登录, 数据库插入用户认证信息失败, err:%+v", userAuthInsertErr)
			}
			return nil
		}); transErr != nil {
			return nil, transErr
		}
	} else {
		// 获取用户信息
		user, err = l.svcCtx.UserModel.FindOne(l.ctx, userAuth.UserId)
		if err != nil {
			return nil, errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "微信登录, 读取用户信息失败, userId: %d, err: %+v", userAuth.UserId, err)
		}
	}

	// 3. 生成 JWT 令牌
	token, generateErr := jwtx.GenerateJwtToken(user.Id, l.svcCtx.Config.JwtAuth.AccessSecret, l.svcCtx.Config.JwtAuth.AccessExpire)
	if generateErr != nil {
		return nil, errors.Wrapf(xerr.NewErrCode(xerr.SERVER_COMMON_ERROR), "微信登录, 生成token失败 : %d", user.Id)
	}

	// 4. 获取当前时间戳
	now := time.Now().Unix()

	return &types.WXMiniAuthResp{
		AccessToken:  token,
		AccessExpire: now + l.svcCtx.Config.JwtAuth.AccessExpire,
		RefreshAfter: now + l.svcCtx.Config.JwtAuth.RefreshAfter,
	}, nil
}

type WxLoginResp struct {
	OpenId     string `json:"openid"`
	SessionKey string `json:"session_key"`
	Unionid    string `json:"unionid"`
	ErrCode    int    `json:"errcode"`
	ErrMsg     string `json:"errmsg"`
}

func (l *WxMiniAuthLogic) exchangeCodeForSession(code string) (response WxLoginResp, err error) {

	// 向微信发出登录请求
	baseURL := "https://api.weixin.qq.com/sns/jscode2session"
	// 创建查询参数
	params := url.Values{}
	params.Add("appid", l.svcCtx.Config.Wxpay.AppID)
	params.Add("secret", l.svcCtx.Config.Wxpay.AppSecret)
	params.Add("js_code", code)
	params.Add("grant_type", "authorization_code")

	// 构建完整的请求 URL
	requestURL := fmt.Sprintf("%s?%s", baseURL, params.Encode())

	// 发送 GET 请求
	resp, err := http.Get(requestURL)
	if err != nil {
		return
	}
	defer resp.Body.Close()

	// 读取响应体
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return
	}
	// 将响应体解析为结构体
	err = json.Unmarshal(body, &response)
	if err != nil {
		return
	}

	if response.ErrCode != 0 {
		err = errors.New(response.ErrMsg)
		return
	}
	return
}