using System.Collections.Concurrent;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;
using NuGet.Configuration;
using NuGet.Protocol;
using NuGet.Protocol.Core.Types;

[MemoryDiagnoser]
public class Program
{
    private static void Main(string[] args)
    {
        BenchmarkRunner.Run<Program>();
    }

    private static PackageSource _nugetOrg = new PackageSource("https://api.nuget.org/v3/index.json", "nuget.org");

    private ConcurrentDictionary<string, SourceRepository> _dictionary = new ConcurrentDictionary<string, SourceRepository>
    {
        [_nugetOrg.Source] = Repository.Factory.GetCoreV3(_nugetOrg.Source),
    };

    private IEnumerable<Lazy<INuGetResourceProvider>> _providers = Repository.Provider.GetCoreV3();

    public IEnumerable<object[]> GetSources()
    {
        yield return [_nugetOrg, FeedType.HttpV3];
    }

    [Benchmark]
    [ArgumentsSource(nameof(GetSources))]
    public SourceRepository AlwaysAlloc(PackageSource source, FeedType feedType)
    {
        return _dictionary.GetOrAdd(source.Source, new SourceRepository(source, _providers, feedType));
    }

    [Benchmark]
    [ArgumentsSource(nameof(GetSources))]
    public SourceRepository TryGetThenAdd(PackageSource source, FeedType feedType)
    {
        if (_dictionary.TryGetValue(source.Source, out var repository))
        {
            return repository;
        }
        return _dictionary.GetOrAdd(source.Source, new SourceRepository(source, _providers, feedType));
    }

    [Benchmark]
    [ArgumentsSource(nameof(GetSources))]
    public SourceRepository AnonFunc(PackageSource source, FeedType feedType)
    {
        return _dictionary.GetOrAdd(source.Source, _ => new SourceRepository(source, _providers, feedType));
    }

    [Benchmark]
    [ArgumentsSource(nameof(GetSources))]
    public SourceRepository StaticRealFunc(PackageSource source, FeedType feedType)
    {
        return _dictionary.GetOrAdd(source.Source, Factory, (_providers, feedType));

        static SourceRepository Factory(string key, (IEnumerable<Lazy<INuGetResourceProvider>>, FeedType) args)
        {
            var (providers, feedType) = args;
            return new SourceRepository(new PackageSource(key), providers, feedType);
        }
    }
}