using System.Globalization;
using System.IO;
using System.Windows;
using Marathon.Application;
using Marathon.Infrastructure;
using Marathon.UI.Services;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Options;
using Serilog;

namespace Marathon.Hosts.WpfBlazor;

/// <summary>
/// WPF application entry-point. Builds an <see cref="IHost"/> with Serilog,
/// configuration (appsettings.json + Local + env vars), and the Marathon UI
/// service collection. Composes Application + Infrastructure modules
/// optionally — those module entry points may not yet exist while parallel
/// Phase 2/3/4 work merges.
/// </summary>
public partial class App : System.Windows.Application
{
    public IHost? Host { get; private set; }

    /// <summary>
    /// Absolute path to the Local override settings file. Resolved from the
    /// host's content root (the directory containing <c>appsettings.json</c>).
    /// </summary>
    public static string SettingsLocalFileName => "appsettings.Local.json";

    protected override void OnStartup(StartupEventArgs e)
    {
        base.OnStartup(e);

        var contentRoot = AppContext.BaseDirectory;
        var localSettingsPath = Path.Combine(contentRoot, SettingsLocalFileName);

        var builder = Microsoft.Extensions.Hosting.Host.CreateApplicationBuilder();
        builder.Environment.ContentRootPath = contentRoot;

        builder.Configuration
            .SetBasePath(contentRoot)
            .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
            .AddJsonFile($"appsettings.{builder.Environment.EnvironmentName}.json", optional: true, reloadOnChange: true)
            .AddJsonFile(SettingsLocalFileName, optional: true, reloadOnChange: true)
            .AddEnvironmentVariables(prefix: "MARATHON_");

        // Serilog — structured rolling-file + console.
        // Minimum level honours the "Serilog:MinimumLevel:Default" key when
        // present in configuration; otherwise defaults to Information.
        var logsDir = Path.Combine(contentRoot, "logs");
        Directory.CreateDirectory(logsDir);

        var minimumLevel = ParseMinimumLevel(builder.Configuration["Serilog:MinimumLevel:Default"]);
        Log.Logger = new LoggerConfiguration()
            .MinimumLevel.Is(minimumLevel)
            .Enrich.FromLogContext()
            .WriteTo.Console()
            .WriteTo.File(
                path: Path.Combine(logsDir, "marathon-.log"),
                rollingInterval: RollingInterval.Day,
                retainedFileCountLimit: 14,
                shared: true)
            .CreateLogger();

        builder.Services.AddSerilog();

        // Marathon.UI services (Mud, localization, options, theme/locale state, settings writer).
        builder.Services.AddMarathonUi(builder.Configuration, localSettingsPath);

        // Blazor WebView root services.
        builder.Services.AddWpfBlazorWebView();
#if DEBUG
        builder.Services.AddBlazorWebViewDeveloperTools();
#endif

        // Application use cases + Infrastructure (persistence, scraping, workers).
        builder.Services.AddMarathonApplication();
        builder.Services.AddMarathonInfrastructure(builder.Configuration);

        // MainWindow needs the IServiceProvider for BlazorWebView.Services binding.
        builder.Services.AddSingleton<MainWindow>();

        Host = builder.Build();

        // Apply EF migrations + WAL pragma BEFORE Host.Start() so the BackgroundServices
        // (LiveOddsPoller, AnomalyDetectionPoller, etc.) don't race the DB schema creation.
        // Resolved in a scope because MarathonDbContextInitializer is Scoped (DbContext lifetime).
        using (var initScope = Host.Services.CreateScope())
        {
            var initializer = initScope.ServiceProvider
                .GetRequiredService<Marathon.Infrastructure.Persistence.MarathonDbContextInitializer>();
            initializer.InitializeAsync().GetAwaiter().GetResult();
        }

        Host.Start();

        // Apply default culture from configuration before any UI renders.
        var localeOptions = Host.Services.GetRequiredService<IOptions<LocalizationOptions>>().Value;
        var locale = Host.Services.GetRequiredService<LocaleState>();
        try
        {
            locale.Set(localeOptions.DefaultCulture);
        }
        catch (CultureNotFoundException)
        {
            locale.Set(LocaleState.Russian);
        }

        var window = Host.Services.GetRequiredService<MainWindow>();
        window.Show();
    }

    private static Serilog.Events.LogEventLevel ParseMinimumLevel(string? raw) =>
        Enum.TryParse<Serilog.Events.LogEventLevel>(raw, ignoreCase: true, out var level)
            ? level
            : Serilog.Events.LogEventLevel.Information;

    protected override void OnExit(ExitEventArgs e)
    {
        try
        {
            Host?.StopAsync(TimeSpan.FromSeconds(5)).GetAwaiter().GetResult();
        }
        catch (Exception ex)
        {
            Log.Error(ex, "Host shutdown failed");
        }
        finally
        {
            Host?.Dispose();
            Log.CloseAndFlush();
            base.OnExit(e);
        }
    }
}