using Microsoft.EntityFrameworkCore;
using Microsoft.OpenApi.Models;
using NLog.Targets;
using NLog.Web;
using OpenTelemetry.Resources;
using OpenTelemetry.Trace;
using System.Text.Json.Serialization;

var builder = WebApplication.CreateBuilder(args);
// recupero env corrente
var env = builder.Environment;
var logger = LogManager.Setup()
                .LoadConfigurationFromAppSettings()
                .GetCurrentClassLogger();

var assemblyVersion = Assembly.GetExecutingAssembly().GetName().Version?.ToString();

ConfigurationManager configuration = builder.Configuration;
logger.Info($"Lux.API | Program.cs: startup | v.{assemblyVersion}");
logger.Info($"Current ASPNETCORE_ENVIRONMENT: {env.EnvironmentName}");

// costruzione connectionMultiplexer redis...
string connStr = configuration.GetConnectionString("Redis") ?? "localhost";
ConnectionMultiplexer redisConn = ConnectionMultiplexer.Connect(connStr);

// ====================================================================
// Setup Tracing e Telemetria...
// ====================================================================

// 1. Leggiamo la configurazione
var otelEnabled = builder.Configuration.GetValue<bool>("Otel:EnableTracing", false);
var otelEndpoint = builder.Configuration["Otel:Endpoint"];
var otelDsn = builder.Configuration["Otel:Dsn"];

if (otelEnabled)
{
    // ====================================================================
    // SETUP OPENTELEMETRY BASE (Genera gli oggetti Activity)
    // Questo gira per i Livelli 1, 2 e 3.
    // ====================================================================
    var appVersion = System.Reflection.Assembly.GetExecutingAssembly().GetName().Version?.ToString() ?? "1.0.0";

    builder.Services.AddOpenTelemetry()
        .WithTracing(tracerProviderBuilder =>
        {
            tracerProviderBuilder
                .SetResourceBuilder(OpenTelemetry.Resources.ResourceBuilder.CreateDefault()
                    .AddService(serviceName: "LUX", serviceVersion: appVersion))
                .AddSource("Lux.API")
                .AddSource("Lux.DATA")
                .AddSource("Lux.UI")
                .AddAspNetCoreInstrumentation(options => { options.Filter = ctx => !ctx.Request.Path.StartsWithSegments("/health"); })
                .AddEntityFrameworkCoreInstrumentation()
                .AddRedisInstrumentation(redisConn);

            // ====================================================================
            // ESPORTAZIONE DI RETE (Solo Livelli 1 e 2)
            // ====================================================================
            if (!string.IsNullOrWhiteSpace(otelEndpoint))
            {
                tracerProviderBuilder.AddOtlpExporter(options =>
                {
                    options.Endpoint = new Uri(otelEndpoint);
                    if (!string.IsNullOrWhiteSpace(otelDsn))
                    {
                        options.Headers = $"uptrace-dsn={otelDsn}";
                    }
                    options.Protocol = OpenTelemetry.Exporter.OtlpExportProtocol.Grpc;
                });
            }
            // Se otelEndpoint è vuoto (Livello 3), le tracce nascono e muoiono in RAM.
        });

    // ====================================================================
    // ESPORTAZIONE NLOG REALTIME (Solo Livelli 1 e 2)
    // ====================================================================
    if (!string.IsNullOrWhiteSpace(otelEndpoint))
    {
        var otlpTarget = new OtlpTarget
        {
            Name = "UptraceRealtime",
            Endpoint = otelEndpoint,
            ServiceName = "LUX.Data.Tracer"
        };

        if (!string.IsNullOrWhiteSpace(otelDsn))
        {
            otlpTarget.Headers = $"uptrace-dsn={otelDsn}";
        }

        var config = LogManager.Configuration ?? new NLog.Config.LoggingConfiguration();
        config.AddTarget(otlpTarget);
        config.AddRule(NLog.LogLevel.Info, NLog.LogLevel.Fatal, otlpTarget);
        LogManager.Configuration = config;
        LogManager.ReconfigExistingLoggers();

        logger.Info($"🚀 NLog & OTel attivi e in invio verso: {otelEndpoint}");
    }
    else
    {
        logger.Info("ℹ️ OTel attivo (Local mode). Esportazione di rete disabilitata.");
    }
}
else
{
    // ====================================================================
    // LIVELLO 4: TUTTO SPENTO
    // ====================================================================
    logger.Info("⏸️ Telemetria e Tracing completamente disabilitati.");
}

// fix logging
builder.Logging.AddFilter("Microsoft.EntityFrameworkCore", Microsoft.Extensions.Logging.LogLevel.None);

// Add services to the container.
builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
//builder.Services.AddSwaggerGen();
builder.Services.AddSwaggerGen(c =>
{
    c.SwaggerDoc("v1", new OpenApiInfo
    {
        Title = "EgaWare's Lux API",
        Version = $"v1 | {assemblyVersion}",
        Description = $"API documentation for v1 | AssemblyVersion {assemblyVersion}"
    });
});


// registro connMultiplexer REDIS
builder.Services.AddSingleton<IConnectionMultiplexer>(redisConn);

var connectionString = builder.Configuration.GetConnectionString("Lux.All") ?? throw new InvalidOperationException("Connection string 'DefaultConnection' not found.");
// DataLayerContext (manca!)
builder.Services.AddDbContextFactory<DataLayerContext>(options =>
{
    var conn = builder.Configuration.GetConnectionString("Lux.All");
    options.UseMySql(conn, ServerVersion.AutoDetect(conn), mySqlOptions =>
    {
        mySqlOptions.EnableStringComparisonTranslations();
    })
    .EnableSensitiveDataLogging(false)
        .EnableDetailedErrors(false)
        .LogTo(_ => { }); // disabilita EF logging;
});
builder.Services.AddDbContextFactory<ReportContext>(options =>
{
    var conn = builder.Configuration.GetConnectionString("Lux.All");
    options.UseMySql(conn, ServerVersion.AutoDetect(conn), mySqlOptions =>
    {
        mySqlOptions.EnableStringComparisonTranslations();
    })
    .EnableSensitiveDataLogging(false)
        .EnableDetailedErrors(false)
        .LogTo(_ => { }); // disabilita EF logging;
});

// fix serializazzione senza loop
builder.Services.AddControllers().AddJsonOptions(options =>
{
    options.JsonSerializerOptions.ReferenceHandler = ReferenceHandler.IgnoreCycles;
});

//// fix serializzazione con NewtonsoftJson e gestione loop...
//builder.Services
//    .AddControllers()
//    .AddNewtonsoftJson(options =>
//    {
//        options.SerializerSettings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore;
//    });


// registrazione in blocco servizi con metodo extension custom
builder.Services.AddLuxData(connectionString);

// servizi con dipendenze" ma Scoped
builder.Services.AddScoped<ExternalMessageProcessor>();

// servizi hosted usano scope factory
builder.Services.AddHostedService<RedisSubscriberService>();
builder.Services.AddHostedService<StatsCollectService>();

var app = builder.Build();

// aggiunt base URL x routing corretto
string baseUrl = configuration.GetValue<string>("ServerConf:BaseUrl") ?? "";
app.UsePathBase(baseUrl);
logger.Info($"BaseUrl: {baseUrl}");

// log channels di ritorno UI
List<string> listParams = new List<string>() { "ChannelPng", "ChannelSub", "ChannelPub", "ChannelSvg" };
foreach (var param in listParams)
{
    logger.Info($"{param}: {configuration.GetValue<string>($"ServerConf:{param}") ?? ""}");
}


// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment() || app.Environment.IsStaging())
{
    app.UseSwagger();
    //app.UseSwaggerUI();
    app.UseSwaggerUI(c =>
    {
        c.SwaggerEndpoint($"{baseUrl}swagger/v1/swagger.json", "EgalWare's Lux API v1");
    });
}

app.UseHttpsRedirection();

app.UseAuthorization();

app.MapControllers();

// inserisco evento in chiusura x fermare i thread di calcolo sottostanti:
// https://shazwazza.com/post/aspnet-core-application-shutdown-events/
// https://dotnetblog.asphostportal.com/how-to-handle-application-shutdown-in-asp-net-core/
app.Lifetime.ApplicationStopping.Register(() =>
{
#if false
    if (myExecProcessManager != null)
    {
        myExecProcessManager.StopExecutionThread();
    } 
#endif
});

// avvio app
app.Run();