TweetDuck/Browser/Bridge/UpdateBridge.cs

using System;
using System.Diagnostics.CodeAnalysis;
using System.Windows.Forms;
using TweetDuck.Controls;
using TweetLib.Core.Systems.Updates;

namespace TweetDuck.Browser.Bridge {
	[SuppressMessage("ReSharper", "UnusedMember.Global")]
	class UpdateBridge {
		private readonly UpdateHandler updates;
		private readonly Control sync;

		private UpdateInfo nextUpdate = null;

		public event EventHandler<UpdateInfo> UpdateAccepted;
		public event EventHandler<UpdateInfo> UpdateDismissed;

		public UpdateBridge(UpdateHandler updates, Control sync) {
			this.sync = sync;

			this.updates = updates;
			this.updates.CheckFinished += updates_CheckFinished;
		}

		internal void Cleanup() {
			updates.CheckFinished -= updates_CheckFinished;
			nextUpdate?.DeleteInstaller();
		}

		private void updates_CheckFinished(object sender, UpdateCheckEventArgs e) {
			UpdateInfo foundUpdate = e.Result.HasValue ? e.Result.Value : null;

			if (nextUpdate != null && !nextUpdate.Equals(foundUpdate)) {
				nextUpdate.DeleteInstaller();
			}

			nextUpdate = foundUpdate;
		}

		private void HandleInteractionEvent(EventHandler<UpdateInfo> eventHandler) {
			UpdateInfo tmpInfo = nextUpdate;

			if (tmpInfo != null) {
				sync.InvokeAsyncSafe(() => eventHandler?.Invoke(this, tmpInfo));
			}
		}

		// Bridge methods

		public void TriggerUpdateCheck() {
			updates.Check(false);
		}

		public void OnUpdateAccepted() {
			HandleInteractionEvent(UpdateAccepted);
		}

		public void OnUpdateDismissed() {
			HandleInteractionEvent(UpdateDismissed);

			nextUpdate?.DeleteInstaller();
			nextUpdate = null;
		}
	}
}