using IBKRTrader.Core.Database.Migrations;
using IBKRTrader.Core.Logging;
using IBKRTrader.Core.Modularity;
using IBKRTrader.Core.Settings;
using IBKRTrader.Core.Workers;
using IBKRTrader.UI;
using Microsoft.Extensions.DependencyInjection;

namespace IBKRTrader;

/// <summary>
/// Launcher – das Basis-Fenster (Shell). Zeigt je registrierter View einen Button, führt beim Start
/// Migrationen aus, startet Module und die WorkerEngine, und trägt das gemeinsame Fenster-Menü.
/// Die inhaltlichen Ansichten (Logs, Settings, Workers, Module) sind eigenständige Fenster.
/// </summary>
public sealed class LauncherForm : Form
{
    private readonly ShellUiHost           _uiHost;
    private readonly IServiceProvider      _services;
    private readonly LoggingService        _logger;
    private readonly WorkerEngine          _workerEngine;
    private readonly IReadOnlyList<IModule> _modules;

    private readonly Dictionary<string, Button> _viewButtons = new(StringComparer.OrdinalIgnoreCase);
    private readonly FlowLayoutPanel _buttonPanel = new()
    {
        Dock = DockStyle.Fill, Padding = new Padding(16), AutoScroll = true
    };
    private readonly ToolStripStatusLabel _status = new("Start...");

    public LauncherForm(ShellUiHost uiHost, IServiceProvider services)
    {
        _uiHost       = uiHost;
        _services     = services;
        _logger       = services.GetRequiredService<LoggingService>();
        _workerEngine = services.GetRequiredService<WorkerEngine>();
        _modules      = services.GetServices<IModule>().ToList();

        Text          = "IBKRTrader — Launcher";
        Width         = 720;
        Height        = 540;
        StartPosition = FormStartPosition.CenterScreen;

        _uiHost.SetMainWindow(this);

        BuildUi();
        _uiHost.OpenStateChanged += UpdateButtonStates;
    }

    private void BuildUi()
    {
        var menu = new MenuStrip { Dock = DockStyle.Top, ImageScalingSize = new Size(24, 24) };
        WindowMenu.Wire(menu, _uiHost, null);

        foreach (var view in _uiHost.Views.OrderBy(v => v.Order).ThenBy(v => v.Title))
        {
            var id  = view.Id;
            var btn = new Button
            {
                Text = view.Title, Width = 210, Height = 48, Margin = new Padding(8),
                TextAlign = ContentAlignment.MiddleLeft, Image = view.Icon,
                ImageAlign = ContentAlignment.MiddleLeft, TextImageRelation = TextImageRelation.ImageBeforeText
            };
            btn.Click += (_, _) => _uiHost.OpenView(id);
            _viewButtons[id] = btn;
            _buttonPanel.Controls.Add(btn);
        }

        var statusStrip = new StatusStrip();
        statusStrip.Items.Add(_status);

        // Reihenfolge: Fill-Panel zuerst, dann Bottom, dann Top (WinForms Dock-Stacking).
        Controls.Add(_buttonPanel);
        Controls.Add(statusStrip);
        Controls.Add(menu);
        MainMenuStrip = menu;
    }

    protected override void OnLoad(EventArgs e)
    {
        base.OnLoad(e);
        _ = StartupAsync();
    }

    protected override void OnFormClosing(FormClosingEventArgs e)
    {
        // Auch das Schließen-X läuft über die Sicherheitsabfrage.
        if (!_uiHost.ShutdownConfirmed)
        {
            e.Cancel = true;
            BeginInvoke((Action)(() => _uiHost.RequestShutdown()));
            return;
        }

        _uiHost.CloseAllViews();
        try
        {
            foreach (var module in _modules)
                module.StopAsync(default).GetAwaiter().GetResult();
        }
        catch { /* Shutdown darf nicht am Modul scheitern */ }
        _workerEngine.StopAllAsync().GetAwaiter().GetResult();

        base.OnFormClosing(e);
    }

    private async Task StartupAsync()
    {
        _logger.Info("Core", "=== IBKRTrader startet ===");
        _logger.Info("Core", $"Version: 1.0.0 | .NET {Environment.Version}");

        // Log-Level aus Settings.
        var levelStr = _services.GetRequiredService<SettingsService>().Settings.Logging.Level;
        if (Enum.TryParse<AppLogLevel>(levelStr, true, out var level))
            _logger.SetMinLevel(level);

        SetStatus("Migrationen...");
        try
        {
            await _services.GetRequiredService<CoreMigrations>().RunAsync();
            await _services.GetRequiredService<IBKRMigrations>().RunAsync();
        }
        catch (Exception ex)
        {
            _logger.Error("Core", "Core-Datenbankfehler beim Start.", ex);
        }

        foreach (var module in _modules)
        {
            try { await module.StartAsync(default); }
            catch (Exception ex) { _logger.Error(module.Name, $"{module.Name}: Start fehlgeschlagen.", ex); }
        }

        await _workerEngine.StartAllAsync();

        _logger.Info("Core", "IBKRTrader bereit.");
        SetStatus("Bereit");
        UpdateButtonStates();
    }

    private void UpdateButtonStates()
    {
        if (IsDisposed) return;
        if (InvokeRequired) { BeginInvoke((Action)UpdateButtonStates); return; }
        foreach (var (id, btn) in _viewButtons)
            btn.Font = new Font(btn.Font, _uiHost.IsOpen(id) ? FontStyle.Bold : FontStyle.Regular);
    }

    private void SetStatus(string text)
    {
        if (IsDisposed) return;
        if (InvokeRequired) { BeginInvoke((Action)(() => SetStatus(text))); return; }
        _status.Text = $"Status: {text}  |  {DateTime.Now:HH:mm:ss}";
    }
}