API/TOOHUCardAPI/Data/Repositories/UserRepository.cs

using System;
using System.Collections.Generic;
using System.Linq;
using AutoMapper;
using Microsoft.EntityFrameworkCore;
using TOOHUCardAPI.Data.Models;

namespace TOOHUCardAPI.Data.Repositories
{
    public class UserRepository
    {
        private readonly AppDbContext _appDbContext;
        private readonly IMapper _mapper;

        public UserRepository(AppDbContext appDbContext, IMapper mapper)
        {
            _appDbContext = appDbContext;
            _mapper = mapper;
        }

        private IQueryable<User> GetAllUsersQuery()
        {
            return _appDbContext.Users.Include(u => u.EncodedCardGroups).AsQueryable();
        }

        public User GetUser(string steamId)
        {
            return GetAllUsersQuery().FirstOrDefault(user => user.SteamId.Equals(steamId));
        }

        public User CreateUser(string steamId)
        {
            User user = new User()
            {
                SteamId = steamId,
                Vip = true,
                EndTime = DateTime.MaxValue,
                LevelList = string.Empty,
                PetLevel = 1,
                EncodedCardGroups = new List<EncodedCardGroup>()
            };
            _appDbContext.Users.Add(user);
            _appDbContext.SaveChanges();
            return user;
        }

        public User UpdateUser(User user)
        {
            var trackedUser = GetAllUsersQuery().FirstOrDefault(u => u.SteamId == user.SteamId);
            if (trackedUser == default)
            {
                return trackedUser;
            }

            _appDbContext.Update(user);
            _appDbContext.SaveChanges();
            return user;
        }

        public User GetOrCreateUser(string steamId)
        {
            User user = GetUser(steamId) ?? CreateUser(steamId);
            return user;
        }
    }
}