using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.IO;
using System.Threading;
using System.Threading.Tasks;
using VkNet;
using VkNet.Enums;
using VkNet.Enums.Filters;
using VkNet.Exception;
using VkNet.Model;
using VkNet.Model.RequestParams;

namespace MonteceVkBot
{

    class Program
    {

        static VkApi vkapi = new VkApi();
        static long userID = 0;
        static ulong? Ts;
        static ulong? Pts;
        static bool IsActive;
        static Timer WatchTimer = null;
        static byte MaxSleepSteps = 3;
        static int StepSleepTime = 333;
        static byte CurrentSleepSteps = 1;
        delegate void MessagesRecievedDelegate(VkApi owner, ReadOnlyCollection<Message> messages);
        static event MessagesRecievedDelegate NewMessages;

        static Func<string> DoubleCode = () =>
        {
            Console.Write("Введите код авторизации: ");
            return Console.ReadLine();
        };

        static void Main(string[] args)
        {
            string Login = "+79045429427";
            string Password = "svetik11";
            ulong ID = 6497404;
            bool DoubleAuth = false;
            ConsoleStyle();
            /*
            Console.Write("Введите логин: ");
            Login = Console.ReadLine();
            Console.Write("Введите пароль: ");
            Password = Console.ReadLine();
            Console.Write("Введите ID приложения: ");
            ID = ulong.Parse(Console.ReadLine());
            Console.Write("Есть двухэтапный аутификатор? (1/0): ");
            DoubleAuth = Convert.ToBoolean(Convert.ToInt32(Console.ReadLine()));
            */

            Console.WriteLine("Попытка авторизации...");

            if (Auth(Login, Password, ID, DoubleAuth))
            {
                ColorMessage("Авторизация успешно завершена.", ConsoleColor.Green);
                User I = vkapi.Users.Get(vkapi.UserId.Value);
                Console.WriteLine("Вы: " + I.FirstName + " " + I.LastName);
                Eye();
                ColorMessage("Слежение за сообщениями активировано.", ConsoleColor.Yellow);
            }
            else
            {
                ColorMessage("Не удалось произвести авторизацию!", ConsoleColor.Red);
            }

            Console.WriteLine("Нажмите ENTER чтобы выйти...");
            Console.ReadLine();
        }

        static void ConsoleStyle()
        {
            Console.Title = "Montece VK bot";
            ColorMessage("Montece VK bot", ConsoleColor.Yellow);
        }

        static void ColorMessage(string text, ConsoleColor color)
        {
            Console.ForegroundColor = color;
            Console.WriteLine(text);
            Console.ForegroundColor = ConsoleColor.Gray;
        }

        static bool Auth(string Login, string Password, ulong ID, bool HasCode)
        {
            try
            {
                if (HasCode == true)
                {
                    vkapi.Authorize(new ApiAuthParams
                    {
                        Login = Login,
                        Password = Password,
                        Settings = Settings.All,
                        ApplicationId = ID,
                        TwoFactorAuthorization = DoubleCode
                    });
                    return true;
                }
                else
                {
                    vkapi.Authorize(new ApiAuthParams
                    {
                        Login = Login,
                        Password = Password,
                        Settings = Settings.All,
                        ApplicationId = ID
                    });
                    return true;
                }
            }
            catch
            {
                return false;
            }
        }

        static string[] Commands = { "помощь", "привет", "регистрация" };

        static void Command(string Message)
        {
            Message = Message.ToLower();
            if (Message == Commands[0])
            {
                string msg = "";
                for (int j = 0; j < Commands.Length; j++) msg += Commands[j] + ", ";
                SendMessage(msg);
            }
            else if (Message == Commands[1])
            {
                SendMessage("Приветик!!!)))");
            }
            else if (Message == Commands[2])
            {
                SendMessage("Введите поддомен");
                var user = new Users();
                user.subdomain = Message;
                File.AppendAllText("lol.txt", user.subdomain);
            }
            /*else if (Message == Commands[2])
            {
                SendMessage("MESSAGETEXT");
            }*/
            //else
            //{
            //    SendMessage("Неизвестная команда. Напишите 'Помощь' для получения списка команд.");

            //}
        }

        static void Registration(string Message)
        {
            SendMessage("Введите поддомен");
            var user = new Users();
            user.subdomain = Message;
            File.AppendAllText("lol.txt", user.subdomain);
        }

        static void SendMessage(string Body)
        {
            try
            {
                vkapi.Messages.Send(new MessagesSendParams
                {
                    UserId = userID,
                    Message = Body
                });
            }
            catch(Exception e)
            {
                ColorMessage("Ошибка! " + e.Message, ConsoleColor.Red);
            }

        }

        static void Eye()
        {
            LongPollServerResponse Pool = vkapi.Messages.GetLongPollServer(true);
            StartAsync(Pool.Ts, Pool.Pts);
            NewMessages += Watcher_NewMessages;
        }

        static void Watcher_NewMessages(VkApi owner, ReadOnlyCollection<Message> messages)
        {
            for (int i = 0; i < messages.Count; i++)
            {
                if (messages[i].Type != MessageType.Sended)
                {
                    User Sender = vkapi.Users.Get(messages[i].UserId.Value);
                    Console.WriteLine("Новое сообщение: {0} {1}: {2}", Sender.FirstName, Sender.LastName, messages[i].Body);
                    userID = messages[i].UserId.Value;
                    Console.Beep();
                    Command(messages[i].Body);
                }
            }
        }

        static LongPollServerResponse GetLongPoolServer(ulong? lastPts = null)
        {
            LongPollServerResponse response = vkapi.Messages.GetLongPollServer(false, lastPts == null);
            Ts = response.Ts;
            Pts = Pts == null ? response.Pts : lastPts;
            return response;
        }

        static Task<LongPollServerResponse> GetLongPoolServerAsync(ulong? lastPts = null)
        {
            return Task.Run(() =>
            {
                return GetLongPoolServer(lastPts);
            });
        }

        static LongPollHistoryResponse GetLongPoolHistory()
        {
            if (!Ts.HasValue) GetLongPoolServer(null);
            MessagesGetLongPollHistoryParams rp = new MessagesGetLongPollHistoryParams();
            rp.Ts = Ts.Value;
            rp.Pts = Pts;
            int i = 0;
            LongPollHistoryResponse history = null;
            string errorLog = "";

            while (i < 5 && history == null)
            {
                i++;
                try
                {
                    history = vkapi.Messages.GetLongPollHistory(rp);
                }
                catch (TooManyRequestsException)
                {
                    Thread.Sleep(150);
                    i--;
                }
                catch (Exception ex)
                {
                    errorLog += string.Format("{0} - {1}{2}", i, ex.Message, Environment.NewLine);
                }
            }

            if (history != null)
            {
                Pts = history.NewPts;
                foreach (var m in history.Messages)
                {
                    m.FromId = m.Type == MessageType.Sended ? vkapi.UserId : m.UserId;
                }
            }
            else ColorMessage(errorLog, ConsoleColor.Red);
            return history;
        }

        static Task<LongPollHistoryResponse> GetLongPoolHistoryAsync()
        {
            return Task.Run(() => { return GetLongPoolHistory(); });
        }

        static async void WatchAsync(object state)
        {
            LongPollHistoryResponse history = await GetLongPoolHistoryAsync();
            if (history.Messages.Count > 0)
            {
                CurrentSleepSteps = 1;
                NewMessages?.Invoke(vkapi, history.Messages);
            }
            else if (CurrentSleepSteps < MaxSleepSteps) CurrentSleepSteps++;
            WatchTimer.Change(CurrentSleepSteps * StepSleepTime, Timeout.Infinite);
        }

        static async void StartAsync(ulong? lastTs = null, ulong? lastPts = null)
        {
            if (IsActive) ColorMessage("Messages for {0} already watching", ConsoleColor.Red);
            IsActive = true;
            await GetLongPoolServerAsync(lastPts);
            WatchTimer = new Timer(new TimerCallback(WatchAsync), null, 0, Timeout.Infinite);
        }

        static void Stop()
        {
            if (WatchTimer != null) WatchTimer.Dispose();
            IsActive = false;
            WatchTimer = null;
        }
    }
}