osu/osu.Game/Online/DownloadTrackingComposite.cs

197 lines
7.1 KiB
C#

// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
// See the LICENCE file in the repository root for full licence text.
using System;
using JetBrains.Annotations;
using osu.Framework.Allocation;
using osu.Framework.Bindables;
using osu.Framework.Graphics.Containers;
using osu.Game.Database;
using osu.Game.Online.API;
namespace osu.Game.Online
{
/// <summary>
/// A component which tracks a <typeparamref name="TModel"/> through potential download/import/deletion.
/// </summary>
public abstract class DownloadTrackingComposite<TModel, TModelManager> : CompositeDrawable
where TModel : class, IEquatable<TModel>
where TModelManager : class, IModelDownloader<TModel>, IModelManager<TModel>
{
protected readonly Bindable<TModel> Model = new Bindable<TModel>();
[Resolved(CanBeNull = true)]
protected TModelManager Manager { get; private set; }
/// <summary>
/// Holds the current download state of the <typeparamref name="TModel"/>, whether is has already been downloaded, is in progress, or is not downloaded.
/// </summary>
protected readonly Bindable<DownloadState> State = new Bindable<DownloadState>();
protected readonly BindableNumber<double> Progress = new BindableNumber<double> { MinValue = 0, MaxValue = 1 };
protected DownloadTrackingComposite(TModel model = null)
{
Model.Value = model;
}
private IBindable<WeakReference<TModel>> managerUpdated;
private IBindable<WeakReference<TModel>> managerRemoved;
private IBindable<WeakReference<ArchiveDownloadRequest<TModel>>> managerDownloadBegan;
private IBindable<WeakReference<ArchiveDownloadRequest<TModel>>> managerDownloadFailed;
[BackgroundDependencyLoader(true)]
private void load()
{
Model.BindValueChanged(modelInfo =>
{
if (modelInfo.NewValue == null)
attachDownload(null);
else if (IsModelAvailableLocally())
State.Value = DownloadState.LocallyAvailable;
else
attachDownload(Manager?.GetExistingDownload(modelInfo.NewValue));
}, true);
if (Manager == null)
return;
managerDownloadBegan = Manager.DownloadBegan.GetBoundCopy();
managerDownloadBegan.BindValueChanged(downloadBegan);
managerDownloadFailed = Manager.DownloadFailed.GetBoundCopy();
managerDownloadFailed.BindValueChanged(downloadFailed);
managerUpdated = Manager.ItemUpdated.GetBoundCopy();
managerUpdated.BindValueChanged(itemUpdated);
managerRemoved = Manager.ItemRemoved.GetBoundCopy();
managerRemoved.BindValueChanged(itemRemoved);
}
/// <summary>
/// Checks that a database model matches the one expected to be downloaded.
/// </summary>
/// <example>
/// For online play, this could be used to check that the databased model matches the online beatmap.
/// </example>
/// <param name="databasedModel">The model in database.</param>
protected virtual bool VerifyDatabasedModel([NotNull] TModel databasedModel) => true;
/// <summary>
/// Whether the given model is available in the database.
/// By default, this calls <see cref="IModelManager{TModel}.IsAvailableLocally"/>,
/// but can be overriden to add additional checks for verifying the model in database.
/// </summary>
protected virtual bool IsModelAvailableLocally() => Manager?.IsAvailableLocally(Model.Value) == true;
private void downloadBegan(ValueChangedEvent<WeakReference<ArchiveDownloadRequest<TModel>>> weakRequest)
{
if (weakRequest.NewValue.TryGetTarget(out var request))
{
Schedule(() =>
{
if (request.Model.Equals(Model.Value))
attachDownload(request);
});
}
}
private void downloadFailed(ValueChangedEvent<WeakReference<ArchiveDownloadRequest<TModel>>> weakRequest)
{
if (weakRequest.NewValue.TryGetTarget(out var request))
{
Schedule(() =>
{
if (request.Model.Equals(Model.Value))
attachDownload(null);
});
}
}
private ArchiveDownloadRequest<TModel> attachedRequest;
private void attachDownload(ArchiveDownloadRequest<TModel> request)
{
if (attachedRequest != null)
{
attachedRequest.Failure -= onRequestFailure;
attachedRequest.DownloadProgressed -= onRequestProgress;
attachedRequest.Success -= onRequestSuccess;
}
attachedRequest = request;
if (attachedRequest != null)
{
if (attachedRequest.Progress == 1)
{
Progress.Value = 1;
State.Value = DownloadState.Importing;
}
else
{
Progress.Value = attachedRequest.Progress;
State.Value = DownloadState.Downloading;
attachedRequest.Failure += onRequestFailure;
attachedRequest.DownloadProgressed += onRequestProgress;
attachedRequest.Success += onRequestSuccess;
}
}
else
{
State.Value = DownloadState.NotDownloaded;
}
}
private void onRequestSuccess(string _) => Schedule(() => State.Value = DownloadState.Importing);
private void onRequestProgress(float progress) => Schedule(() => Progress.Value = progress);
private void onRequestFailure(Exception e) => Schedule(() => attachDownload(null));
private void itemUpdated(ValueChangedEvent<WeakReference<TModel>> weakItem)
{
if (weakItem.NewValue.TryGetTarget(out var item))
{
Schedule(() =>
{
if (!item.Equals(Model.Value))
return;
if (!VerifyDatabasedModel(item))
{
State.Value = DownloadState.NotDownloaded;
return;
}
State.Value = DownloadState.LocallyAvailable;
});
}
}
private void itemRemoved(ValueChangedEvent<WeakReference<TModel>> weakItem)
{
if (weakItem.NewValue.TryGetTarget(out var item))
{
Schedule(() =>
{
if (item.Equals(Model.Value))
State.Value = DownloadState.NotDownloaded;
});
}
}
#region Disposal
protected override void Dispose(bool isDisposing)
{
base.Dispose(isDisposing);
State.UnbindAll();
attachDownload(null);
}
#endregion
}
}