package useCases

import (
	"RenewCMS/internal/domain/hash"
	"RenewCMS/internal/domain/invite"
	"RenewCMS/internal/domain/user"
	"errors"
	"strings"
	"time"
)

type AcceptInviteUseCase struct {
	userRepository   user.Repository
	inviteRepository invite.Repository
	hasher           hash.Hasher
}

type AcceptInviteCommand struct {
	Code     string
	Username string
	Password string
}

func NewAcceptInviteUseCase(userRepository user.Repository, inviteRepository invite.Repository, hasher hash.Hasher) *AcceptInviteUseCase {
	return &AcceptInviteUseCase{userRepository, inviteRepository, hasher}
}

func (a *AcceptInviteUseCase) AcceptInvite(command AcceptInviteCommand) (user.User, error) {
	now := time.Now()

	pending, err := findUsableInvite(a.inviteRepository, a.hasher, command.Code, now)
	if err != nil {
		return user.User{}, err
	}

	if a.emailHasAccount(pending.Email) {
		return user.User{}, invite.ErrEmailHasAccount
	}

	if err := a.ensureUsernameFree(command.Username); err != nil {
		return user.User{}, err
	}

	hashedPassword, err := a.hasher.Hash(command.Password)
	if err != nil {
		return user.User{}, err
	}

	createdUser, err := a.userRepository.Create(user.User{
		Username:   command.Username,
		Password:   hashedPassword,
		Email:      pending.Email,
		IsVerified: true,
	})
	if err != nil {
		return user.User{}, err
	}

	if err := a.inviteRepository.MarkAccepted(pending.ID, now); err != nil {
		if deleteErr := a.userRepository.Delete(createdUser.ID); deleteErr != nil {
			return user.User{}, errors.Join(err, deleteErr)
		}
		return user.User{}, err
	}

	return createdUser, nil
}

func (a *AcceptInviteUseCase) emailHasAccount(email string) bool {
	for _, existingUser := range a.userRepository.GetAll() {
		if strings.EqualFold(existingUser.Email, email) {
			return true
		}
	}
	return false
}

func (a *AcceptInviteUseCase) ensureUsernameFree(username string) error {
	_, err := a.userRepository.GetByUsername(username)
	if err == nil {
		return user.ErrUsernameTaken
	}
	if errors.Is(err, user.ErrUserNotFound) {
		return nil
	}
	return err
}