using System;
using System.ComponentModel;
using System.Linq;
using System.Windows.Forms;
using PolyTrader.Modules.CopyTrading.Persistence;
using PolyTraderSharp;
using PolyTraderSharp.Models;

namespace PolyTrader.Modules.CopyTrading.Ui
{
    /// <summary>
    /// Verwaltung der Master-Trader (mod_copytrading_traders): Liste, Detail-Editor
    /// (PropertyGrid) und Account-Zuweisung (welche Accounts diesen Trader kopieren).
    /// Persistiert über das Repo und hält den Hot-Path-State
    /// (<see cref="CopyTradingState.Traders"/>) synchron.
    /// Layout im Designer (MasterTradersView.Designer.cs), Daten/Logik hier.
    /// </summary>
    public partial class MasterTradersView : Form
    {
        private ITrackedTraderRepository? _repo;
        private TradingState? _state;
        private CopyTradingState? _copyState;

        private BindingList<TrackedTrader> _binding = new();
        private TrackedTrader? _current;

        // Parameterloser Konstruktor für den WinForms-Designer.
        public MasterTradersView()
        {
            InitializeComponent();

            colWinrate.DefaultCellStyle.Format = "F1";
            colPnl.DefaultCellStyle.Format = "F2";

            tsNew.Click += (_, _) => AddNew();
            tsSave.Click += (_, _) => SaveCurrent();
            tsDelete.Click += (_, _) => DeleteCurrent();
            tsRefresh.Click += (_, _) => LoadData();
            grid.SelectionChanged += (_, _) => OnSelectionChanged();
        }

        /// <summary>Injiziert die Abhängigkeiten (nach der DI-Auflösung) und lädt die Trader.</summary>
        public void Initialize(ITrackedTraderRepository repo, TradingState state, CopyTradingState copyState)
        {
            _repo = repo;
            _state = state;
            _copyState = copyState;
            LoadData();
        }

        private void LoadData()
        {
            if (_repo == null) return;

            var traders = _repo.GetAll().OrderBy(t => t.Id).ToList();
            _binding = new BindingList<TrackedTrader>(traders);
            grid.DataSource = _binding;
            if (traders.Count > 0)
                grid.CurrentCell = grid.Rows[0].Cells[0];
            else
                ClearDetail();
            lblHint.Text = $"{traders.Count} Master-Trader geladen.";
        }

        private void OnSelectionChanged()
        {
            if (grid.CurrentRow?.DataBoundItem is TrackedTrader t)
                BindDetail(t);
        }

        private void BindDetail(TrackedTrader trader)
        {
            _current = trader;
            pgDetail.SelectedObject = trader;

            clbAccounts.Items.Clear();
            if (_state == null) return;
            foreach (var acc in _state.Accounts.Values.OrderBy(a => a.AccountId))
            {
                string label = string.IsNullOrEmpty(acc.Name) ? $"#{acc.AccountId}" : $"{acc.Name} (#{acc.AccountId}){(acc.IsDemo ? " · Demo" : "")}";
                int idx = clbAccounts.Items.Add(new AccountItem(acc.AccountId, label));
                clbAccounts.SetItemChecked(idx, trader.AssignedAccountIds.Contains(acc.AccountId));
            }
        }

        private void ClearDetail()
        {
            _current = null;
            pgDetail.SelectedObject = null;
            clbAccounts.Items.Clear();
        }

        private void AddNew()
        {
            int nextId = _binding.Count > 0 ? _binding.Max(t => t.Id) + 1 : 1;
            var trader = new TrackedTrader { Id = nextId, DisplayName = $"Neuer Trader {nextId}" };
            _binding.Add(trader);
            grid.CurrentCell = grid.Rows[_binding.Count - 1].Cells[0];
            lblHint.Text = $"Neuer Master-Trader #{nextId} – Felder ausfüllen und Speichern.";
        }

        private void SaveCurrent()
        {
            if (_current == null || _repo == null || _copyState == null) { lblHint.Text = "Kein Trader ausgewählt."; return; }

            _current.AssignedAccountIds = clbAccounts.CheckedItems.Cast<AccountItem>().Select(a => a.Id).ToHashSet();

            _repo.Upsert(_current);
            _copyState.Traders[_current.Id] = _current;
            grid.Refresh();
            lblHint.Text = $"Gespeichert: #{_current.Id} {_current.DisplayName} ({_current.AssignedAccountIds.Count} Account(s)) um {DateTime.Now:HH:mm:ss}.";
        }

        private void DeleteCurrent()
        {
            if (_current == null || _repo == null || _copyState == null) { lblHint.Text = "Kein Trader ausgewählt."; return; }
            var id = _current.Id;
            if (MessageBox.Show($"Master-Trader #{id} ({_current.DisplayName}) wirklich löschen?",
                    "Löschen bestätigen", MessageBoxButtons.YesNo, MessageBoxIcon.Warning) != DialogResult.Yes)
                return;

            _repo.Delete(id);
            _copyState.Traders.TryRemove(id, out _);
            _binding.Remove(_current);
            ClearDetail();
            lblHint.Text = $"Master-Trader #{id} gelöscht.";
        }

        private sealed record AccountItem(int Id, string Label)
        {
            public override string ToString() => Label;
        }
    }
}