telegram-bot/Core/Handler/GeneralHandler.cs

using System;
using System.Threading.Tasks;
using BotFramework;
using BotFramework.Attributes;
using Kruzya.TelegramBot.Core.Data;
using Microsoft.EntityFrameworkCore;
using Telegram.Bot.Types;

namespace Kruzya.TelegramBot.Core.Handler;

public class GeneralHandler : BotEventHandler
{
    [AttributeUsage(AttributeTargets.Method)]
    public sealed class HandleEverythingAttribute : HandlerAttribute
    {
        protected override bool CanHandle(HandlerParams param)
        {
            return true;
        }
    }

    protected readonly CoreContext databaseContext;

    public GeneralHandler(CoreContext dbCtx)
    {
        databaseContext = dbCtx;
    }

    [HandleEverything]
    [Priority(short.MaxValue - 10)]
    public async Task<bool> Listener()
    {
        foreach (var message in new Message[] { RawUpdate.Message, RawUpdate.EditedMessage, RawUpdate.ChannelPost, RawUpdate.EditedChannelPost })
        {
            if (message == null)
            {
                continue;
            }

            await VerifyChatPair(message);
        }

        return true;
    }

    public async Task VerifyChatPair(Message message)
    {
        await VerifyChatPair(message.Chat, message.From);
    }

    public async Task VerifyChatPair(Chat chat, User user)
    {
        await VerifyChatPair(chat.Id, user.Id);
    }

    public async Task VerifyChatPair(long chat, long user)
    {
        var hasEntry = await databaseContext.Users.AnyAsync(e => e.ChatId == chat && e.UserId == user);
        if (hasEntry)
        {
            return;
        }

        await MakeChatPair(chat, user);
    }

    public async Task MakeChatPair(long chat, long user)
    {
        await databaseContext.Users.AddAsync(new BotUser()
        {
            ChatId = chat,
            UserId = user
        });
    }
}