// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using Microsoft.DotNet.Cli.Utils;
using Microsoft.DotNet.Configurer;
using Microsoft.TemplateEngine.Abstractions;
using Microsoft.TemplateEngine.Abstractions.TemplatePackage;

namespace Microsoft.DotNet.Cli.Commands.New;

internal class OptionalWorkloadProvider : ITemplatePackageProvider
{
    private readonly IEngineEnvironmentSettings _environmentSettings;

    internal OptionalWorkloadProvider(ITemplatePackageProviderFactory factory, IEngineEnvironmentSettings settings)
    {
        Factory = factory;
        _environmentSettings = settings;
    }

    public ITemplatePackageProviderFactory Factory { get; }

    // To avoid warnings about being unused, implement empty add/remove accessors.
    event Action? ITemplatePackageProvider.TemplatePackagesChanged
    {
        add { }
        remove { }
    }

    public Task<IReadOnlyList<ITemplatePackage>> GetAllTemplatePackagesAsync(CancellationToken cancellationToken)
    {
        var list = new List<TemplatePackage>();
        var optionalWorkloadLocator = new TemplateLocator.TemplateLocator();
        var sdksDirectory = new DirectoryInfo(MSBuildForwardingAppWithoutLogging.GetMSBuildSDKsPath());
        var sdkDirectory = sdksDirectory?.Parent;
        var sdkVersion = sdkDirectory?.Name;
        var dotnetRootPath = sdkDirectory?.Parent?.Parent;
        string userProfileDir = CliFolderPathCalculator.DotnetUserProfileFolderPath;

        var packages = optionalWorkloadLocator.GetDotnetSdkTemplatePackages(sdkVersion, dotnetRootPath?.FullName, userProfileDir);
        var fileSystem = _environmentSettings.Host.FileSystem;
        foreach (var packageInfo in packages)
        {
            list.Add(new TemplatePackage(this, packageInfo.Path, fileSystem.GetLastWriteTimeUtc(packageInfo.Path)));
        }
        return Task.FromResult<IReadOnlyList<ITemplatePackage>>(list);
    }
}