using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Http;
using Microsoft.Extensions.Logging;
using Microsoft.Maui.Hosting;
using Microsoft.Maui.LifecycleEvents;
using OpenTelemetry;
using OpenTelemetry.Logs;
using OpenTelemetry.Metrics;
using OpenTelemetry.Trace;
using System.Text.RegularExpressions;
 
namespace Microsoft.Extensions.Hosting;
 
// Adds common Aspire services: service discovery, resilience, health checks, and OpenTelemetry.
// This project should be referenced by each service project in your solution.
// To learn more about using this project, see https://aka.ms/dotnet/aspire/service-defaults
public static class Extensions
{
    public static TBuilder AddServiceDefaults<TBuilder>(this TBuilder builder) where TBuilder : IHostApplicationBuilder
    {
        builder.ConfigureOpenTelemetry();
 
        builder.Services.AddServiceDiscovery();
 
        builder.Services.ConfigureHttpClientDefaults(http =>
        {
            // Turn on resilience by default
            http.AddStandardResilienceHandler();
 
            // Turn on service discovery by default
            http.AddServiceDiscovery();
        });
 
        // Uncomment the following to restrict the allowed schemes for service discovery.
        // builder.Services.Configure<ServiceDiscoveryOptions>(options =>
        // {
        //     options.AllowedSchemes = ["https"];
        // });
 
        return builder;
    }
 
    public static MauiAppBuilder AddServiceDefaults(this MauiAppBuilder builder)
    {
        builder.ConfigureOpenTelemetry();
 
        builder.Services.AddServiceDiscovery();
 
        builder.Services.ConfigureHttpClientDefaults(http =>
        {
            // Turn on resilience by default
            http.AddStandardResilienceHandler();
 
            // Turn on service discovery by default
            http.AddServiceDiscovery();
        });
 
        builder.Services.TryAddEnumerable(
            ServiceDescriptor.Transient<IMauiInitializeService, OpenTelemetryInitializer>(_ => new OpenTelemetryInitializer()));
 
        // Uncomment the following to restrict the allowed schemes for service discovery.
        // builder.Services.Configure<ServiceDiscoveryOptions>(options =>
        // {
        //     options.AllowedSchemes = ["https"];
        // });
 
        return builder;
    }
 
    public static TBuilder ConfigureOpenTelemetry<TBuilder>(this TBuilder builder) where TBuilder : IHostApplicationBuilder
    {
        builder.Logging.AddOpenTelemetry(logging =>
        {
            logging.IncludeFormattedMessage = true;
            logging.IncludeScopes = true;
        });
 
        builder.Services.AddOpenTelemetry()
            .WithMetrics(metrics =>
            {
                // Uncomment the following line to enable reporting metrics coming from the .NET MAUI SDK, this might cause a lot of added telemetry
                //metrics.AddMeter("Microsoft.Maui");
 
                metrics.AddHttpClientInstrumentation()
                    .AddRuntimeInstrumentation();
            })
            .WithTracing(tracing =>
            {
                // Uncomment the following line to enable reporting tracing coming from the .NET MAUI SDK, this might cause a lot of added telemetry
                //tracing.AddSource("Microsoft.Maui");
 
                tracing.AddSource(builder.Environment.ApplicationName)
                    // Uncomment the following line to enable gRPC instrumentation (requires the OpenTelemetry.Instrumentation.GrpcNetClient package)
                    //.AddGrpcClientInstrumentation()
                    .AddHttpClientInstrumentation();
            });
 
        builder.AddOpenTelemetryExporters();
 
        return builder;
    }
 
    // OpenTelemetry initializer for MAUI
    private sealed class OpenTelemetryInitializer : IMauiInitializeService
    {
        public void Initialize(IServiceProvider services)
        {
            services.GetService<MeterProvider>();
            services.GetService<TracerProvider>();
            services.GetService<LoggerProvider>();
        }
    }
 
    private static TBuilder AddOpenTelemetryExporters<TBuilder>(this TBuilder builder) where TBuilder : IHostApplicationBuilder
    {
        var useOtlpExporter = !string.IsNullOrWhiteSpace(builder.Configuration["OTEL_EXPORTER_OTLP_ENDPOINT"]);
 
        if (useOtlpExporter)
        {
            builder.Services.AddOpenTelemetry().UseOtlpExporter();
        }
 
        return builder;
    }
}