using Microsoft.EntityFrameworkCore;
using YPS.Beer.Data;
using YPS.Beer.Models;

namespace YPS.Beer.Services;

public class BeerService : IBeerService
{
    private readonly BeerContext _context;

    public BeerService(BeerContext context)
    {
        _context = context;
    }

    public async Task<User?> GetUserById(string userId) =>
        await _context.Users
            .Include(u => u.Favourites)
            .SingleOrDefaultAsync(u => u.Id == userId);

    public async Task<Favourite?> AddFavouriteToUser(string userId, Favourite favourite)
    {
        var user = await GetUserById(userId);

        if (user is null)
            return null;

        if (user.Favourites.Any(f => f.BeerId == favourite.BeerId))
            return null;

        user.Favourites.Add(favourite);

        await _context.SaveChangesAsync();

        return favourite;
    }
}