using System;
using System.Collections.ObjectModel;
using System.Linq;
using System.Threading.Tasks;
using System.Windows.Input;
using Alpaca.Markets;
using DesktopBot.Engine;
using DesktopBot.Models;
using DesktopBot.Services;

namespace DesktopBot.ViewModels
{
    /// <summary>
    /// ViewModel del pannello Bot Manager.
    /// Contiene un unico bot BTC/USD fisso, precaricato all'avvio.
    /// L'utente può soltanto avviarlo e fermarlo.
    /// </summary>
    public class BotsManagerViewModel : BaseViewModel
    {
        private readonly ITradingService _tradingService;

        // ── Collezione (sempre 1 elemento: il bot BTC/USD fisso) ─────────────
        public ObservableCollection<BotInstanceViewModel> Bots { get; }
            = new ObservableCollection<BotInstanceViewModel>();

        /// <summary>Shortcut diretto al bot fisso BTC/USD.</summary>
        public BotInstanceViewModel BtcBot => Bots.FirstOrDefault();

        // ── Grafico prezzi BTC/USD ─────────────────────────────────────────
        public PriceChartViewModel ChartVM { get; }

        // ── Stato UI ─────────────────────────────────────────────────────────
        private string _statusMessage;
        public string StatusMessage
        {
            get => _statusMessage;
            set => SetProperty(ref _statusMessage, value);
        }

        // ── Comandi ──────────────────────────────────────────────────────────
        public ICommand StartBotCommand { get; }
        public ICommand StopBotCommand  { get; }
        public ICommand SaveAllCommand  { get; }

        // ── Ctor ─────────────────────────────────────────────────────────────
        public BotsManagerViewModel(ITradingService tradingService)
        {
            _tradingService = tradingService ?? throw new ArgumentNullException(nameof(tradingService));

            ChartVM = new PriceChartViewModel(tradingService);

            StartBotCommand = new RelayCommand(_ => BtcBot?.StartBot(), _ => BtcBot != null && !BtcBot.IsRunning);
            StopBotCommand  = new RelayCommand(_ => BtcBot?.ForceStop(), _ => BtcBot != null && BtcBot.IsRunning);
            SaveAllCommand  = new RelayCommand(_ => SaveAll());

            EnsureBtcBotExists();

            // Avvia streaming grafico in background
            _ = ChartVM.StartStreamingAsync();
        }

        // ── Preload bot BTC/USD fisso ─────────────────────────────────────────
        private void EnsureBtcBotExists()
        {
            // Tenta di caricare da disco
            var saved = BotInstanceStore.Load();
            var btcModel = saved.FirstOrDefault(m =>
                string.Equals(m.Symbol, "BTCUSD", StringComparison.OrdinalIgnoreCase));

            if (btcModel == null)
            {
                // Prima esecuzione: crea il bot BTC/USD con parametri ottimali
                btcModel = CreateBtcUsdBot();
                BotInstanceStore.Save(new[] { btcModel });
            }

            var vm = new BotInstanceViewModel(btcModel, _tradingService);
            // Il bot fisso non può essere rimosso — ignoriamo RemoveRequested
            Bots.Add(vm);
            StatusMessage = "Bot BTC/USD caricato — pronto all'avvio.";
        }

        private static BotInstance CreateBtcUsdBot()
        {
            var config = new BotConfiguration
            {
                Symbol               = "BTCUSD",
                Quantity             = 1,
                CheckIntervalSeconds = 60,
                AnalysisTimeFrame    = BarTimeFrame.Minute,
                HistoricalBarCount   = 200,

                // EMA ottimizzate per 1min BTC
                FastEmaPeriod        = 5,
                SlowEmaPeriod        = 20,

                // RSI
                RsiPeriod            = 14,
                RsiOversoldThreshold  = 30,
                RsiOverboughtThreshold = 70,

                // MACD
                MacdFastPeriod       = 8,
                MacdSlowPeriod       = 21,
                MacdSignalPeriod     = 5,

                // Keltner / RVOL
                KeltnerPeriod        = 20,
                KeltnerMultiplier    = 2.0m,
                RvolMinThreshold     = 2.0m,
                AtrStopMultiplier    = 1.5m,

                // Kalman
                KalmanDelta          = 5e-6,
                KalmanObservationVariance = 1.0,
                KalmanEntryZScore    = 1.8,
                KalmanExitZScore     = 0.3,

                // Risk
                StopLossPercentage   = 0.02m,
                TakeProfitPercentage = 0.04m,
                MaxPositionSizePercent = 0.10m,

                // Algoritmo BTC/USD avanzato (dispatch automatico nell'engine)
                Strategy             = TradingStrategy.VOLATILITY_BREAKOUT,
                RecommendedStrategy  = TradingStrategy.VOLATILITY_BREAKOUT,
                IsLocked             = true,
                LockedAt             = DateTime.Now
            };

            var model = new BotInstance
            {
                Name       = "BTC/USD — Algoritmo Avanzato",
                BadgeColor = "#F7931A",   // arancione Bitcoin
                Config     = config,
                Notes      = "Bot predefinito BTC/USD. Algoritmo multi-segnale: Regime Detector + Kalman + ATR Sizing.",
                CreatedAt  = DateTime.Now,
                IsEnabled  = true
            };

            // Blocca asset e config (bot fisso)
            model.Symbol    = "BTCUSD";
            model.AssetName = "Bitcoin / US Dollar";
            model.AssetClass = "crypto";
            model.LockToAsset();

            return model;
        }

        // ── Persistenza ──────────────────────────────────────────────────────
        public void SaveAll()
        {
            BotInstanceStore.Save(Bots.Select(vm => vm.Model));
            StatusMessage = $"Salvato — {DateTime.Now:HH:mm:ss}";
        }

        // ── Start / Stop esposto ai comandi ───────────────────────────────────
        private async Task StartAllAsync()
        {
            if (BtcBot != null && !BtcBot.IsRunning)
                BtcBot.StartBot();
            await Task.CompletedTask;
        }

        private void StopAll()
        {
            if (BtcBot?.IsRunning == true)
                BtcBot.ForceStop();
            StatusMessage = "Bot fermato.";
        }
    }
}