package com.krylov.refound.service;

import com.krylov.refound.entity.Favorite;
import com.krylov.refound.entity.Post;
import com.krylov.refound.entity.User;
import com.krylov.refound.enums.ErrorCode;
import com.krylov.refound.exception.ApiException;
import com.krylov.refound.repository.FavoriteRepository;
import com.krylov.refound.repository.PostRepository;
import java.util.List;
import lombok.RequiredArgsConstructor;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Service;

@Service
@RequiredArgsConstructor
public class FavoriteService {
  private final FavoriteRepository repository;
  private final PostRepository postRepository;
  private final UserService userService;

  public void addToFavorites(Long postId) {

    User user = userService.getCurrentUser();

    Post post = postRepository.findById(postId)
        .orElseThrow(() -> new ApiException(ErrorCode.NOT_FOUND, "Post not found", HttpStatus.NOT_FOUND));

    if (repository.existsByUserAndPost(user, post)) {
      return; // уже есть
    }

    Favorite favorite = new Favorite();
    favorite.setUser(user);
    favorite.setPost(post);

    repository.save(favorite);
  }

  public void removeFromFavorites(Long postId) {

    User user = userService.getCurrentUser();

    Post post = postRepository.findById(postId)
        .orElseThrow(() -> new ApiException(ErrorCode.NOT_FOUND, "Post not found", HttpStatus.NOT_FOUND));

    repository.deleteByUserAndPost(user, post);
  }

  public List<Post> getFavorites() {
    User user = userService.getCurrentUser();

    return repository.findByUser(user)
        .stream()
        .map(Favorite::getPost)
        .toList();
  }

  public void toggle(Long postId) {

    User user = userService.getCurrentUser();

    Post post = postRepository.findById(postId)
        .orElseThrow(() -> new ApiException(
            ErrorCode.NOT_FOUND,
            "Post not found",
            HttpStatus.NOT_FOUND
        ));

    if (repository.existsByUserAndPost(user, post)) {
      repository.deleteByUserAndPost(user, post);
    } else {
      Favorite f = new Favorite();
      f.setUser(user);
      f.setPost(post);
      repository.save(f);
    }
  }
}