package user

import (
	"context"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"strings"
	"time"
	"tyc-server/app/main/model"
	"tyc-server/common/ctxdata"
	"tyc-server/common/xerr"

	"github.com/pkg/errors"

	"tyc-server/app/main/api/internal/svc"
	"tyc-server/app/main/api/internal/types"

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

type WxH5AuthLogic struct {
	logx.Logger
	ctx    context.Context
	svcCtx *svc.ServiceContext
}

func NewWxH5AuthLogic(ctx context.Context, svcCtx *svc.ServiceContext) *WxH5AuthLogic {
	return &WxH5AuthLogic{
		Logger: logx.WithContext(ctx),
		ctx:    ctx,
		svcCtx: svcCtx,
	}
}

func (l *WxH5AuthLogic) WxH5Auth(req *types.WXH5AuthReq) (resp *types.WXH5AuthResp, err error) {
	// Step 1: 使用code获取access_token
	accessTokenResp, err := l.GetAccessToken(req.Code)
	if err != nil {
		return nil, errors.Wrapf(xerr.NewErrCode(xerr.SERVER_COMMON_ERROR), "获取access_token失败: %v", err)
	}

	// 已登录正式用户 + 静默授权 code：把当前公众号 openid 写入 user_auth(wxh5_openid)，供微信内 JSAPI 支付使用
	if claims, claimsErr := ctxdata.GetClaimsFromCtx(l.ctx); claimsErr == nil && claims != nil && claims.UserType == model.UserTypeNormal {
		return l.bindWxh5OpenidToNormalUser(claims.UserId, accessTokenResp.Openid)
	}

	// Step 2: 查找用户授权信息
	userAuth, findErr := l.svcCtx.UserAuthModel.FindOneByAuthTypeAuthKey(l.ctx, model.UserAuthTypeWxh5OpenID, accessTokenResp.Openid)
	if findErr != nil && !errors.Is(findErr, model.ErrNotFound) {
		return nil, errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "查询用户授权失败: %v", findErr)
	}

	// Step 3: 处理用户信息
	var userID int64
	var userType int64
	if userAuth != nil {
		// 已存在用户，直接登录
		userID = userAuth.UserId
		userType = model.UserTypeNormal
	} else {
		// 检查临时用户表
		userTemp, err := l.svcCtx.UserTempModel.FindOneByAuthTypeAuthKey(l.ctx, model.UserAuthTypeWxh5OpenID, accessTokenResp.Openid)
		if err != nil && !errors.Is(err, model.ErrNotFound) {
			return nil, errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "查询用户临时信息失败: %v", err)
		}

		if userTemp == nil {
			// 创建临时用户记录
			userTemp = &model.UserTemp{
				AuthType: model.UserAuthTypeWxh5OpenID,
				AuthKey:  accessTokenResp.Openid,
			}
			result, err := l.svcCtx.UserTempModel.Insert(l.ctx, nil, userTemp)
			if err != nil {
				return nil, errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "创建临时用户信息失败: %v", err)
			}
			userID, err = result.LastInsertId()
			if err != nil {
				return nil, errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "获取新创建的临时用户ID失败: %v", err)
			}
		} else {
			userID = userTemp.Id
		}
		userType = model.UserTypeTemp
	}

	// Step 4: 生成JWT Token
	token, err := l.svcCtx.UserService.GeneralUserToken(l.ctx, userID, userType)
	if err != nil {
		return nil, errors.Wrapf(xerr.NewErrCode(xerr.SERVER_COMMON_ERROR), "生成JWT token失败: %v", err)
	}

	// Step 5: 返回登录结果
	now := time.Now().Unix()
	return &types.WXH5AuthResp{
		AccessToken:  token,
		AccessExpire: now + l.svcCtx.Config.JwtAuth.AccessExpire,
		RefreshAfter: now + l.svcCtx.Config.JwtAuth.RefreshAfter,
	}, nil
}

// bindWxh5OpenidToNormalUser 将 snsapi_base 换得的 openid 绑定到当前正式用户（插入或更新 user_auth）。
// 临时用户不能走此分支：需在绑定手机号时由 TempUserBindUser 写入 user_auth，避免与临时转正逻辑冲突。
func (l *WxH5AuthLogic) bindWxh5OpenidToNormalUser(normalUserID int64, openid string) (*types.WXH5AuthResp, error) {
	openid = strings.TrimSpace(openid)
	if openid == "" {
		return nil, errors.Wrapf(xerr.NewErrCode(xerr.SERVER_COMMON_ERROR), "微信 openid 为空")
	}
	existingByOpenid, err := l.svcCtx.UserAuthModel.FindOneByAuthTypeAuthKey(l.ctx, model.UserAuthTypeWxh5OpenID, openid)
	if err != nil && !errors.Is(err, model.ErrNotFound) {
		return nil, errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "查询 wxh5_openid 失败: %v", err)
	}
	if existingByOpenid != nil && existingByOpenid.UserId != normalUserID {
		return nil, errors.Wrapf(xerr.NewErrMsg("该微信已绑定其他账号"), "wxh5_openid 已被占用 user_id=%d", existingByOpenid.UserId)
	}
	rowByUser, err := l.svcCtx.UserAuthModel.FindOneByUserIdAuthType(l.ctx, normalUserID, model.UserAuthTypeWxh5OpenID)
	if errors.Is(err, model.ErrNotFound) {
		_, insErr := l.svcCtx.UserAuthModel.Insert(l.ctx, nil, &model.UserAuth{
			UserId:   normalUserID,
			AuthType: model.UserAuthTypeWxh5OpenID,
			AuthKey:  openid,
		})
		if insErr != nil {
			return nil, errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "写入 wxh5_openid 失败: %v", insErr)
		}
		logx.WithContext(l.ctx).Infof("[WxH5Auth] 已写入 user_auth wxh5_openid user_id=%d", normalUserID)
	} else if err != nil {
		return nil, errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "查询用户 wxh5_openid 失败: %v", err)
	} else if rowByUser.AuthKey != openid {
		rowByUser.AuthKey = openid
		if _, updErr := l.svcCtx.UserAuthModel.Update(l.ctx, nil, rowByUser); updErr != nil {
			return nil, errors.Wrapf(xerr.NewErrCode(xerr.DB_ERROR), "更新 wxh5_openid 失败: %v", updErr)
		}
		logx.WithContext(l.ctx).Infof("[WxH5Auth] 已更新 user_auth wxh5_openid user_id=%d", normalUserID)
	}

	token, err := l.svcCtx.UserService.GeneralUserToken(l.ctx, normalUserID, model.UserTypeNormal)
	if err != nil {
		return nil, errors.Wrapf(xerr.NewErrCode(xerr.SERVER_COMMON_ERROR), "生成JWT token失败: %v", err)
	}
	now := time.Now().Unix()
	return &types.WXH5AuthResp{
		AccessToken:  token,
		AccessExpire: now + l.svcCtx.Config.JwtAuth.AccessExpire,
		RefreshAfter: now + l.svcCtx.Config.JwtAuth.RefreshAfter,
	}, nil
}

type AccessTokenResp struct {
	AccessToken string `json:"access_token"`
	Openid      string `json:"openid"`
}

// GetAccessToken 通过code获取access_token
func (l *WxH5AuthLogic) GetAccessToken(code string) (*AccessTokenResp, error) {
	appID := l.svcCtx.Config.WechatH5.AppID
	appSecret := l.svcCtx.Config.WechatH5.AppSecret

	url := fmt.Sprintf("https://api.weixin.qq.com/sns/oauth2/access_token?appid=%s&secret=%s&code=%s&grant_type=authorization_code", appID, appSecret, code)

	resp, err := http.Get(url)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}

	var accessTokenResp AccessTokenResp
	if err = json.Unmarshal(body, &accessTokenResp); err != nil {
		return nil, err
	}

	if accessTokenResp.AccessToken == "" || accessTokenResp.Openid == "" {
		return nil, errors.New("accessTokenResp.AccessToken为空")
	}

	return &accessTokenResp, nil
}