package hello.hellospring.service;

import hello.hellospring.domain.Member;
import hello.hellospring.repository.MemberRepository;
import hello.hellospring.repository.MemoryMemberRepository; // DI 적용 전 코드
import java.util.List;
import java.util.Optional;

public class MemberService {

    // private final MemberRepository memberRepository = new MemoryMemberRepository();       // DI 적용 전
    private final MemberRepository memberRepository; // DI 적용 후

    public MemberService(MemberRepository memberRepository) { // DI 적용 후
        this.memberRepository = memberRepository;
    }

    /**
     * 회원가입
     */
    public Long join(Member member) {
        validateDuplicateMember(member); //중복 회원 검증
        memberRepository.save(member);
        return member.getId();
    }

    private void validateDuplicateMember(Member member) {
        memberRepository.findByName(member.getName())
                .ifPresent(m -> {
                    throw new IllegalStateException("이미 존재하는 회원입니다.");
                });
    }

    /**
     * 전체 회원 조회
     */
    public List<Member> findMembers() {
        return memberRepository.findAll();
    }

    public Optional<Member> findOne(Long memberId) {
        return memberRepository.findById(memberId);
    }
}