using Foxchat.Core.Database;
using Foxchat.Core.Federation;
using Microsoft.AspNetCore.Builder;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using NodaTime;
using Serilog;
using Serilog.Events;

namespace Foxchat.Core.Extensions;

public static class ServiceCollectionExtensions
{
    /// <summary>
    /// Adds Serilog to this service collection. This method also initializes Serilog so it should be called as early as possible, before any log calls.
    /// </summary>
    public static void AddSerilog(this WebApplicationBuilder builder)
    {
        var config = builder.Configuration.Get<CoreConfig>() ?? new();

        var logCfg = new LoggerConfiguration()
            .Enrich.FromLogContext()
            .MinimumLevel.Is(config.Logging.LogEventLevel)
            // ASP.NET's built in request logs are extremely verbose, so we use Serilog's instead.
            // Serilog doesn't disable the built-in logs, so we do it here.
            .MinimumLevel.Override("Microsoft", LogEventLevel.Information)
            .MinimumLevel.Override("Microsoft.EntityFrameworkCore.Database.Command",
                config.Logging.LogQueries ? LogEventLevel.Information : LogEventLevel.Warning)
            .MinimumLevel.Override("Microsoft.AspNetCore.Hosting", LogEventLevel.Warning)
            .MinimumLevel.Override("Microsoft.AspNetCore.Mvc", LogEventLevel.Warning)
            .MinimumLevel.Override("Microsoft.AspNetCore.Routing", LogEventLevel.Warning)
            .WriteTo.Console();

        if (config.Logging.SeqLogUrl != null)
            logCfg.WriteTo.Seq(config.Logging.SeqLogUrl, restrictedToMinimumLevel: LogEventLevel.Verbose);

        Log.Logger = logCfg.CreateLogger();

        // AddSerilog doesn't seem to add an ILogger to the service collection, so add that manually.
        builder.Services.AddSerilog().AddSingleton(Log.Logger);
    }

    /// <summary>
    /// Adds the core Foxchat services to this service collection.
    /// </summary>
    public static IServiceCollection AddCoreServices<T>(this IServiceCollection services) where T : IDatabaseContext
    {
        services.AddDbContext<T>();

        // NodaTime recommends only depending on the IClock interface, not the singleton.
        services.AddSingleton<IClock>(SystemClock.Instance);
        // Some core services rely on an IDatabaseContext, not the server-specific context type.
        services.AddScoped<IDatabaseContext, T>();
        services.AddSingleton<RequestSigningService>();

        return services;
    }

    public static T AddConfiguration<T>(this WebApplicationBuilder builder, string? configFile = null)
        where T : class, new()
    {
        builder.Configuration.Sources.Clear();
        builder.Configuration.AddConfiguration(configFile);

        var config = builder.Configuration.Get<T>() ?? new();
        var coreConfig = builder.Configuration.Get<CoreConfig>() ?? new();
        builder.Services.AddSingleton(config);
        builder.Services.AddSingleton(coreConfig);
        return config;
    }

    public static IConfigurationBuilder AddConfiguration(this IConfigurationBuilder builder, string? configFile = null)
    {
        var file = Environment.GetEnvironmentVariable("FOXCHAT_CONFIG_FILE") ?? configFile ?? "config.ini";

        return builder
            .SetBasePath(Directory.GetCurrentDirectory())
            .AddIniFile(file, optional: false, reloadOnChange: true)
            .AddEnvironmentVariables();
    }
}