using System;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;
using StellaOps.Graph.Indexer.Ingestion.Sbom;

namespace StellaOps.Graph.Indexer.Incremental;

public static class GraphChangeStreamServiceCollectionExtensions
{
    public static IServiceCollection AddGraphChangeStreamProcessor(
        this IServiceCollection services,
        Action<GraphChangeStreamOptions>? configureOptions = null)
    {
        ArgumentNullException.ThrowIfNull(services);

        if (configureOptions is not null)
        {
            services.Configure(configureOptions);
        }
        else
        {
            services.Configure<GraphChangeStreamOptions>(_ => { });
        }

        services.TryAddSingleton<IGraphChangeEventSource, NoOpGraphChangeEventSource>();
        services.TryAddSingleton<IGraphBackfillSource, NoOpGraphChangeEventSource>();
        services.TryAddSingleton<IIdempotencyStore, InMemoryIdempotencyStore>();
        services.TryAddSingleton<IGraphDocumentWriter, InMemoryGraphDocumentWriter>();
        services.AddSingleton<GraphBackfillMetrics>();
        services.AddHostedService<GraphChangeStreamProcessor>();
        return services;
    }
}