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

#nullable disable

using Microsoft.NET.Sdk.WorkloadManifestReader;

namespace Microsoft.DotNet.Cli.Commands.Workload.List;

internal class InstalledWorkloadsCollection
{
    private readonly Dictionary<string, string> _workloads;

    /// <summary>
    /// Gets the number of workloads in the collection.
    /// </summary>
    public int Count => _workloads.Count;

    /// <summary>
    /// Creates a new <see cref="InstalledWorkloadsCollection"/> instance using a collection of workload IDs
    /// and a common installation source.
    /// </summary>
    /// <param name="workloadIds">A collection of workload identifiers.</param>
    /// <param name="installationSource">A string describing the installation source of the workload identifiers.</param>
    public InstalledWorkloadsCollection(IEnumerable<WorkloadId> workloadIds, string installationSource)
    {
        _workloads = new Dictionary<string, string>(workloadIds.Select(id => new KeyValuePair<string, string>(id.ToString(), installationSource)));
    }

    public InstalledWorkloadsCollection()
    {
        _workloads = [];
    }

    public IEnumerable<KeyValuePair<string, string>> AsEnumerable() =>
        _workloads.AsEnumerable();

    /// <summary>
    /// Adds a new workload ID and installation source. If the ID already exists, the source is appended.
    /// </summary>
    /// <param name="workloadId">The ID of the workload to update.</param>
    /// <param name="installationSource">A string describing the installation source of the workload.</param>
    public void Add(string workloadId, string installationSource)
    {
        if (!_workloads.ContainsKey(workloadId))
        {
            _workloads[workloadId] = installationSource;
        }
        else
        {
            _workloads[workloadId] += $", {installationSource}";
        }
    }
}