telegram-bot/Core/Service/UserService.cs

#nullable enable

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using BotFramework.Abstractions;
using Kruzya.TelegramBot.Core.Cache;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;
using Telegram.Bot;
using Telegram.Bot.Types;

namespace Kruzya.TelegramBot.Core.Service
{
    public class UserService
    {
        private readonly List<long> _superUsers;
        private readonly Dictionary<long, string> _statusMap;
        private readonly ICacheStorage<long, User> _userCache;
        private readonly ITelegramBotClient _bot;
        private readonly ILogger<UserService> _logger;


        public UserService(
            IConfiguration configuration, 
            IBotInstance bot, 
            ICacheStorage<long, User> userCache,
            ILogger<UserService> logger)
        {
            _superUsers = configuration.GetSection("SuperUsers")
                .GetChildren()
                .Select(q => Convert.ToInt64(q.Value))
                .ToList();

            _statusMap = configuration.GetSection("CustomMemberStatus")
                .GetChildren()
                .ToDictionary(x => Convert.ToInt64(x.Key), x => x.Value);

            _userCache = userCache;
            _bot = bot.BotClient;
            _logger = logger;
        }

        public async Task<User> GetUser(long userId, long chatId, bool bypassCache = false)
        {
            if (bypassCache || !_userCache.TryGetValue(userId, out var user))
            {
                if (bypassCache)
                {
                    _logger.LogDebug("Bypassing cache for {UserId}.", userId);
                }
                else
                {
                    _logger.LogDebug("User {UserId} is not found in cache. Fetching from Telegram API.", userId);
                }

                user = await GetUserByChat(chatId, userId);
                CacheUser(user);
            }
         
            return user;
        }

        private void CacheUser(User user)
        {
            // TODO: config entry for TTL
            _userCache.SetValue(user.Id, user, Convert.ToInt32(TimeSpan.FromHours(1).TotalSeconds));
        }
        
        private async Task<User> GetUserByChat(long chatId, long userId)
        {
            return (await _bot.GetChatMemberAsync(chatId, userId)).User;
        }

        public bool IsUserSuper(User user)
        {
            return IsUserSuper(user.Id);
        }
        
        public bool IsUserSuper(long userId)
        {
            return _superUsers.Contains(userId);
        }

        public string? GetUserCustomStatus(long userId)
        {
            return _statusMap.ContainsKey(userId) ? _statusMap[userId] : null;
        }
    }
}