package lishwist

import (
	"errors"
	"fmt"

	"golang.org/x/crypto/bcrypt"
)

var ErrorUsernameTaken = errors.New("Username is taken")

func Register(username, newPassword string) (*User, error) {
	if username == "" {
		return nil, errors.New("Username required")
	}
	if newPassword == "" {
		return nil, errors.New("newPassword required")
	}

	existingUser, _ := getUserByName(username)
	if existingUser != nil {
		return nil, ErrorUsernameTaken
	}

	hashedPasswordBytes, err := bcrypt.GenerateFromPassword([]byte(newPassword), bcrypt.MinCost)
	if err != nil {
		return nil, fmt.Errorf("Failed to hash password: %w", err)
	}

	usersExist, err := hasUsers()
	if err != nil {
		return nil, fmt.Errorf("Failed to count users: %w", err)
	}

	user, err := createUser(username, hashedPasswordBytes, !usersExist)
	if err != nil {
		return nil, fmt.Errorf("Failed to create user: %w\n", err)
	}

	return user, nil
}