// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System;
using System.Threading;
using System.Threading.Tasks;
using NuGet.Common;
using NuGet.Protocol.Core.Types;

namespace NuGet.Protocol
{
    public class PackageMetadataResourceV3Provider : ResourceProvider
    {
        private readonly IEnvironmentVariableReader? _environmentVariableReader;

        public PackageMetadataResourceV3Provider()
            : this(null)
        {
        }

        internal PackageMetadataResourceV3Provider(IEnvironmentVariableReader? environmentVariableReader)
            : base(typeof(PackageMetadataResource), nameof(PackageMetadataResourceV3Provider), nameof(PackageMetadataResourceV2FeedProvider))
        {
            _environmentVariableReader = environmentVariableReader;
        }

        public override async Task<Tuple<bool, INuGetResource?>> TryCreate(SourceRepository source, CancellationToken token)
        {
            PackageMetadataResourceV3? curResource = null;

            if (await source.GetResourceAsync<ServiceIndexResourceV3>(token) != null)
            {
                var regResource = await source.GetResourceAsync<RegistrationResourceV3>(token)
                    ?? throw new InvalidOperationException($"The source '{source.PackageSource.Source}' does not provide {nameof(RegistrationResourceV3)}.");
                var reportAbuseResource = await source.GetResourceAsync<ReportAbuseResourceV3>(token);
                var readmeResource = await source.GetResourceAsync<ReadmeUriTemplateResource>(token);
                var packageDetailsUriResource = await source.GetResourceAsync<PackageDetailsUriResourceV3>(token);

                var httpSourceResource = await source.GetResourceAsync<HttpSourceResource>(token)
                    ?? throw new InvalidOperationException($"The source '{source.PackageSource.Source}' does not provide {nameof(HttpSourceResource)}.");

                // construct a new resource
                curResource = new PackageMetadataResourceV3(
                    httpSourceResource.HttpSource,
                    regResource,
                    reportAbuseResource,
                    packageDetailsUriResource,
                    readmeResource,
                    _environmentVariableReader);
            }

            return new Tuple<bool, INuGetResource?>(curResource != null, curResource);
        }
    }
}