package miniauth

import (
	"errors"
	"net/mail"
	"regexp"

	"git.keks.cloud/kekskurse/miniauth/pkg/smtpclient"
	"git.keks.cloud/kekskurse/miniauth/pkg/userstore"
	"git.keks.cloud/kekskurse/miniauth/pkg/utils"
	"github.com/go-passwd/validator"
	"github.com/rs/zerolog"
)

type Miniauth struct {
	store userstore.Store
	log   zerolog.Logger
	smtp  smtpclient.SMTPClient
}

func NewMiniauth(us userstore.Store, sm smtpclient.SMTPClient) Miniauth {
	m := Miniauth{}
	m.store = us
	m.smtp = sm
	return m
}

func (m Miniauth) RegisterUser(username string, email string, password string) error {
	log := m.log.With().Str("func", "RegisterUser").Str("username", username).Str("mail", email).Logger()
	err := m.checkUsernameForRegistration(username)
	if err != nil {
		return utils.WrapError(ErrUserHasInvalideChars, err, log)
	}

	err = m.checkPasswordForRegistration(password)
	if err != nil {
		return utils.WrapError(ErrPasswordNotComplexEnough, err, log)
	}

	_, err = mail.ParseAddress(email)
	if err != nil {
		return utils.WrapError(ErrMailAddressInvalide, err, log)
	}

	used, err := m.store.MailCheckExists(email)
	if err != nil {
		return utils.WrapError(ErrMailAddressInvalide, err, log)
	}

	if used {
		return utils.WrapError(ErrMailAddressInvalide, errors.New("email alreadys used"), log)
	}

	id, err := m.store.UserWrite(username, password)
	if err != nil {
		return utils.WrapError(ErrCantCreateUser, err, log)
	}

	log = log.With().Int64("userid", id).Logger()

	err = m.store.MailAdd(email, id, true)
	if err != nil {
		return utils.WrapError(ErrCantCreateUser, err, log)
	}

	err = m.smtp.SendMail("register", email, map[string]any{"hash": "abc"})
	if err != nil {
		m.store.MailRemove(email)
		m.store.UserDelete(username)
		return utils.WrapError(ErrCantSendMail, err, log)
	}

	return nil
}

func (m Miniauth) checkPasswordForRegistration(password string) error {
	passwordValidator := validator.New(
		validator.MinLength(15, nil),
		validator.ContainsAtLeast("abcdefghijklmnopqrstuvwxyz", 5, nil),
		validator.ContainsAtLeast("0123456789", 3, nil),
		validator.ContainsAtLeast(",;.:-_#+*?=}])[({/&%$§!<>|", 3, nil))
	err := passwordValidator.Validate(password)
	return err
}

func (m Miniauth) checkUsernameForRegistration(username string) error {
	reg := regexp.MustCompile("^[a-z0-9]{4,25}$")
	if !reg.MatchString(username) {
		return ErrUserHasInvalideChars
	}

	exists, err := m.store.UserExists(username)
	if err != nil {
		return err
	}

	if exists {
		return ErrUsernameIsTaken
	}

	return nil
}