// Copyright (c) Arlo Godfrey. All Rights Reserved.
// Licensed under the GNU Lesser General Public License, Version 3.0 with additional terms.
// See the LICENSE, LICENSE.LESSER and LICENSE.ADDITIONAL files in the project root for more information.

using System;
using System.Threading;
using System.Threading.Tasks;
using OwlCore.ComponentModel;
using StrixMusic.Sdk.AppModels;

namespace StrixMusic.Sdk.Plugins.Model
{
    /// <summary>
    /// An implementation of <see cref="IDownloadable"/> which delegates all member access to the <see cref="Inner"/> implementation,
    /// unless the member is overridden in a derived class which changes the behavior.
    /// </summary>
    public class DownloadablePluginBase : IModelPlugin, IDownloadable, IDelegatable<IDownloadable>
    {
        /// <summary>
        /// Creates a new instance of <see cref="DownloadablePluginBase"/>.
        /// </summary>
        /// <param name="registration">Metadata about the plugin which was provided during registration.</param>
        /// <param name="inner">The implementation which all member access is delegated to, unless the member is overridden in a derived class which changes the behavior.</param>
        internal protected DownloadablePluginBase(ModelPluginMetadata registration, IDownloadable inner)
        {
            Metadata = registration;
            Inner = inner;
        }

        /// <inheritdoc />
        public ModelPluginMetadata Metadata { get; }

        /// <inheritdoc/>
        public IDownloadable Inner { get; set; }

        /// <inheritdoc/>
        public virtual DownloadInfo DownloadInfo => Inner.DownloadInfo;

        /// <inheritdoc/>
        public virtual event EventHandler<DownloadInfo>? DownloadInfoChanged
        {
            add => Inner.DownloadInfoChanged += value;
            remove => Inner.DownloadInfoChanged -= value;
        }

        /// <inheritdoc/>
        public virtual ValueTask DisposeAsync() => Inner.DisposeAsync();

        /// <inheritdoc/>
        public virtual Task StartDownloadOperationAsync(DownloadOperation operation, CancellationToken cancellationToken = default) => Inner.StartDownloadOperationAsync(operation, cancellationToken);
    }
}