MafiaTelegramBot/MafiaTelegramBot/DataBase/EntityDao/StatisticsDao.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using MafiaTelegramBot.DataBase.Entity;
using MafiaTelegramBot.Resources;
using Microsoft.EntityFrameworkCore;

namespace MafiaTelegramBot.DataBase.EntityDao
{
    public static class StatisticsDao
    {
        private static readonly MafiaDataBase DataBase = MafiaDataBase.GetInstance();
        
        public static async Task<Dictionary<Roles, StatisticsEntity>> GetStatisticsListById(long userId)
        {
            if (await UserDataExists(userId))
            {
                var list = await DataBase.Statistics.Where(s => s.UserId == userId).ToListAsync();
                return list.ToDictionary(item => Enum.Parse<Roles>(item.Role), item => item);
            }
            var roles = Enum.GetValues(typeof(Roles)).Cast<Roles>();
            foreach (var role in roles)
            {
                var statsRow = new StatisticsEntity { UserId = userId, Role = role.ToString() };
                await DataBase.Statistics.AddAsync(statsRow);
            }
            await DataBase.SaveChangesAsync();
            var result = await DataBase.Statistics.Where(s => s.UserId == userId).ToListAsync();
            return result.ToDictionary(item => Enum.Parse<Roles>(item.Role), item => item);
        }
        
        private static async Task<bool> UserDataExists(long id)
        {
            return await DataBase.Statistics.AnyAsync(entity => entity.UserId == id);
        }
    }
}