package service

import (
	"context"
	"github.com/gogf/gf/v2/errors/gerror"
	"github.com/gogf/gf/v2/os/gtime"
	"golang.org/x/crypto/bcrypt"
	"service.xpcool.com/internal/consts"
	"service.xpcool.com/internal/dao"
	"service.xpcool.com/internal/library/jwt"
	"service.xpcool.com/internal/library/response"
	"service.xpcool.com/internal/model/do"
	"service.xpcool.com/internal/model/dto"
	"service.xpcool.com/internal/model/entity"
)

// WechatResolver 抽象微信 code 换 openid，避免业务层依赖具体 HTTP 实现。
type WechatResolver interface {
	OpenID(context.Context, string) (string, error)
}
type SMSVerifier interface {
	Verify(context.Context, string, string) error
}

// userAuth 负责用户三种登录方式及令牌签发，不承担第三方平台通信细节。
type userAuth struct {
	tokens *jwt.Service
	wechat WechatResolver
	sms    SMSVerifier
}

func NewUserAuth(tokens *jwt.Service, wechat WechatResolver, sms SMSVerifier) IUserAuth {
	return &userAuth{tokens, wechat, sms}
}
func (s *userAuth) Login(ctx context.Context, in dto.UserLoginInput) (*dto.TokenPair, uint64, error) {
	var u entity.User
	var err error
	switch in.LoginType {
	case "wechat":
		// 微信首次授权成功后按 openid 自动创建用户。
		if s.wechat == nil {
			return nil, 0, response.Error(consts.CodeInternal, "wechat provider not configured")
		}
		openID, e := s.wechat.OpenID(ctx, in.Code)
		if e != nil {
			return nil, 0, gerror.Wrap(e, "wechat login")
		}
		err = dao.User.Ctx(ctx).Where(do.User{OpenId: openID}).Scan(&u)
		if err != nil {
			return nil, 0, gerror.Wrap(err, "query user")
		}
		if u.Id == 0 {
			id, e := dao.User.Ctx(ctx).Data(do.User{OpenId: openID, Nickname: "微信用户", Status: 1}).InsertAndGetId()
			if e != nil {
				return nil, 0, gerror.Wrap(e, "create user")
			}
			u.Id = uint64(id)
		}
	case "mobile":
		// 验证码由注入的服务校验，校验成功后按手机号自动注册。
		if s.sms == nil {
			return nil, 0, response.Error(consts.CodeInternal, "sms provider not configured")
		}
		if err = s.sms.Verify(ctx, in.Mobile, in.VerifyCode); err != nil {
			return nil, 0, response.Error(consts.CodeInvalidParam, "invalid verification code")
		}
		err = dao.User.Ctx(ctx).Where(do.User{Mobile: in.Mobile}).Scan(&u)
		if err != nil {
			return nil, 0, gerror.Wrap(err, "query user")
		}
		if u.Id == 0 {
			id, e := dao.User.Ctx(ctx).Data(do.User{Mobile: in.Mobile, Nickname: "用户" + in.Mobile[7:], Status: 1}).InsertAndGetId()
			if e != nil {
				return nil, 0, gerror.Wrap(e, "create user")
			}
			u.Id = uint64(id)
		}
	case "password":
		// 密码只使用 bcrypt 比对哈希值，任何场景都不回传或记录明文。
		err = dao.User.Ctx(ctx).Where(do.User{Account: in.Account}).Scan(&u)
		if err != nil {
			return nil, 0, gerror.Wrap(err, "query user")
		}
		if u.Id == 0 || bcrypt.CompareHashAndPassword([]byte(u.PasswordHash), []byte(in.Password)) != nil {
			return nil, 0, response.Error(consts.CodeUserPasswordWrong, "account or password incorrect")
		}
	default:
		return nil, 0, response.Error(consts.CodeUserLoginType, "unsupported login type")
	}
	if u.Status != 1 {
		return nil, 0, response.Error(consts.CodeForbidden, "user disabled")
	}
	_, err = dao.User.Ctx(ctx).Where(do.User{Id: u.Id}).Data(do.User{LastLoginAt: gtime.Now()}).Update()
	if err != nil {
		return nil, 0, gerror.Wrap(err, "update login time")
	}
	return s.issue(ctx, u.Id, in.Terminal)
}
func (s *userAuth) Refresh(ctx context.Context, refresh string) (*dto.TokenPair, uint64, error) {
	// 刷新时先校验 JWT，再以 JTI 原子撤销旧会话，实现单次使用的令牌轮换。
	c, err := s.tokens.Parse(refresh, "refresh", "user")
	if err != nil {
		return nil, 0, response.Error(consts.CodeUnauthorized, "invalid refresh token")
	}
	result, err := dao.AuthRefreshSession.Ctx(ctx).Where(do.AuthRefreshSession{Jti: c.JTI}).WhereNull("revoked_at").Data(do.AuthRefreshSession{RevokedAt: gtime.Now()}).Update()
	if err != nil {
		return nil, 0, gerror.Wrap(err, "撤销旧刷新令牌失败")
	}
	affected, err := result.RowsAffected()
	if err != nil || affected != 1 {
		return nil, 0, response.Error(consts.CodeUnauthorized, "刷新令牌已失效")
	}
	return s.issue(ctx, c.Subject, c.Terminal)
}

// issue 签发 JWT 后把 refresh token 的 JTI 落库，确保可以撤销和追踪设备会话。
func (s *userAuth) issue(ctx context.Context, id uint64, terminal string) (*dto.TokenPair, uint64, error) {
	a, r, exp, err := s.tokens.Issue(id, "user", terminal)
	if err != nil {
		return nil, 0, gerror.Wrap(err, "issue token")
	}
	claims, err := s.tokens.Parse(r, "refresh", "user")
	if err != nil {
		return nil, 0, gerror.Wrap(err, "解析新刷新令牌失败")
	}
	_, err = dao.AuthRefreshSession.Ctx(ctx).Data(do.AuthRefreshSession{SubjectId: id, Scope: "user", Terminal: terminal, Jti: claims.JTI, ExpiredAt: gtime.NewFromTimeStamp(claims.ExpireAt)}).Insert()
	if err != nil {
		return nil, 0, gerror.Wrap(err, "保存刷新令牌会话失败")
	}
	return &dto.TokenPair{AccessToken: a, RefreshToken: r, ExpiresIn: exp}, id, nil
}