package panel

import (
	"errors"

	"gorm.io/gorm"

	"github.com/mhsanaei/3x-ui/v3/internal/database"
	"github.com/mhsanaei/3x-ui/v3/internal/database/model"
	"github.com/mhsanaei/3x-ui/v3/internal/logger"
	"github.com/mhsanaei/3x-ui/v3/internal/util/crypto"
	"github.com/mhsanaei/3x-ui/v3/internal/web/service"
)

// UserService provides business logic for user management and authentication.
// It handles user creation, login, password management, and 2FA operations.
type UserService struct {
	settingService service.SettingService
}

// GetFirstUser retrieves the first user from the database.
// This is typically used for initial setup or when there's only one admin user.
func (s *UserService) GetFirstUser() (*model.User, error) {
	db := database.GetDB()

	user := &model.User{}
	err := db.Model(model.User{}).
		First(user).
		Error
	if err != nil {
		return nil, err
	}
	return user, nil
}

func (s *UserService) CheckUser(username string, password string) (*model.User, error) {
	db := database.GetDB()

	user := &model.User{}

	err := db.Model(model.User{}).
		Where("username = ?", username).
		First(user).
		Error
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return nil, errors.New("invalid credentials")
	} else if err != nil {
		logger.Warning("check user err:", err)
		return nil, err
	}

	if !crypto.CheckPasswordHash(user.Password, password) {
		return nil, errors.New("invalid credentials")
	}

	return user, nil
}

func (s *UserService) BumpLoginEpoch() error {
	db := database.GetDB()
	return db.Model(model.User{}).
		Where("1 = 1").
		Update("login_epoch", gorm.Expr("login_epoch + 1")).
		Error
}

func (s *UserService) UpdateUser(id int, username string, password string) error {
	db := database.GetDB()
	hashedPassword, err := crypto.HashPasswordAsBcrypt(password)
	if err != nil {
		return err
	}

	return db.Model(model.User{}).
		Where("id = ?", id).
		Updates(map[string]any{
			"username":    username,
			"password":    hashedPassword,
			"login_epoch": gorm.Expr("login_epoch + 1"),
		}).
		Error
}

func (s *UserService) UpdateFirstUser(username string, password string) error {
	if username == "" {
		return errors.New("username can not be empty")
	} else if password == "" {
		return errors.New("password can not be empty")
	}
	hashedPassword, er := crypto.HashPasswordAsBcrypt(password)

	if er != nil {
		return er
	}

	db := database.GetDB()
	user := &model.User{}
	err := db.Model(model.User{}).First(user).Error
	if database.IsNotFound(err) {
		user.Username = username
		user.Password = hashedPassword
		return db.Model(model.User{}).Create(user).Error
	} else if err != nil {
		return err
	}
	user.Username = username
	user.Password = hashedPassword
	user.LoginEpoch++
	return db.Save(user).Error
}