coin_alerts/Messenger.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;
using Telegram.Bot;
using Telegram.Bot.Exceptions;
using Telegram.Bot.Polling;
using Telegram.Bot.Types;
using Telegram.Bot.Types.Enums;
namespace SignalsTest
{
    public class Messenger
    {

        TelegramBotClient botClient;

        private static Messenger m_instance;
        public static Messenger instance {  get { if (m_instance == null) { m_instance = new Messenger(); } return m_instance; } }
      
        public const string chatId = "@doralockscryptosignals";
        public const string chatId_test = "@SignalTestPrivate";

        public Dictionary<string,string> messagesSchedule = new Dictionary<string, string>();

        public void ScheduleMessage(string text, string filename=""){
            messagesSchedule.Add(text,filename);
        }

        public async void InitializeScheduler(){
            string _chatId = RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ? chatId_test : chatId;

            while(true){
                await Task.Delay(3500);
                if(messagesSchedule.Count <=0){
                    continue;
                }

                string message = messagesSchedule.Keys.ElementAt(0);
                string filename = messagesSchedule[message];

                try{
                    if(filename.Length < 2){
                        await botClient.SendTextMessageAsync(_chatId, message);
                    }else{
                        FileStream fsSource = new FileStream($"{filename}.png", FileMode.Open, FileAccess.Read);
                        InputFile photo = InputFile.FromStream(fsSource);
                        await botClient.SendPhotoAsync(_chatId, photo,caption: message);
                    }

                    messagesSchedule.Remove(message);
                }catch(Exception e){
                    Console.WriteLine($"Error occured while sending {message} to {filename}");
                    Console.WriteLine(e.ToString());
                }
                
            }
        }

        public Messenger() 
        {
            botClient = new TelegramBotClient(Secrets.TELEGRAM_BOT_TOKEN);
            using CancellationTokenSource cts = new();

            // StartReceiving does not block the caller thread. Receiving is done on the ThreadPool.
            ReceiverOptions receiverOptions = new()
            {
                AllowedUpdates = Array.Empty<UpdateType>() // receive all update types except ChatMember related updates
            };

            InitializeScheduler();
        }
    }
}