using Microsoft.Extensions.DependencyInjection;
using System;
using System.Collections.Generic;
using System.Text.Json;
using System.Threading;
using System.Threading.Tasks;
using Telegram.Bot;
using ZaoBot.Config;

namespace ZaoBot
{
	class BotService
	{
		private JsonDocument config;
		static ITelegramBotClient botClient;
		Dictionary<long, IUserState> userStates = new Dictionary<long, IUserState>();
		private OpenHab.OpenHabClient openhab;
		private IServiceProvider services;

		bool shouldRestart = false;

		public BotService(IServiceProvider services, IConfig config, OpenHab.OpenHabClient openhab)
		{
			this.services = services;
			this.config = config.Data;
			this.openhab = openhab;
		}

		public void Run()
		{
			shouldRestart = false;

			var botClient = services.GetRequiredService<ITelegramBotClient>();

			using CancellationTokenSource cts = new CancellationTokenSource();
			try
			{
				var me = botClient.GetMeAsync().Result;
				Console.WriteLine($"Hello, World! I am user {me.Id} and my name is {me.FirstName}.");
				botClient.StartReceiving(
					updateHandler: OnBotUpdateAsync,
					pollingErrorHandler: OnPollingError,
					cancellationToken: cts.Token
					);
				while (!shouldRestart)
				{
					Thread.Sleep(1000);
				}
			}
			finally
			{
				cts.Cancel();
			}
		}

		private Task OnPollingError(ITelegramBotClient bot, Exception exception, CancellationToken cts)
		{
			Console.WriteLine("Error on polling: " + exception.Message);
			Console.WriteLine("Will restart");
			shouldRestart = true;
			return Task.CompletedTask;
		}

		async Task OnBotUpdateAsync(ITelegramBotClient bot, Telegram.Bot.Types.Update updateInfo, CancellationToken cts)
		{
			if (updateInfo.Message == null) return;
			try
			{
				if (updateInfo.Message.Text != null)
				{
					var id = updateInfo.Message.Chat.Id;
					IUserState state = null;
					if (userStates.ContainsKey(id))
					{
						state = userStates[id];
					}
					if (state == null)
					{
						state = services.GetService<MainMenuUserState>();
					}
					state = await state.ProcessMessage(state, updateInfo);
					if (state == null)
					{
						await botClient.SendTextMessageAsync(
							chatId: updateInfo.Message.Chat,
							text: "Я запутался, давайте сначала"
						);
						state = services.GetService<MainMenuUserState>();
						state = await state.ProcessMessage(state, updateInfo);
					}
					userStates[id] = state;
				}
			}
			catch (Exception ex)
			{
				Console.WriteLine("Exception: " + ex.Message);
				Console.WriteLine(ex.StackTrace);
				Console.WriteLine("Restarting bot");
				shouldRestart = true;
			}
		}
	}
}