From 7f6c8e6a709a55d9672bef5602293be8a3b662b6 Mon Sep 17 00:00:00 2001
From: Darth Affe <darthaffe@wyrez.org>
Date: Wed, 25 Jan 2017 20:51:08 +0100
Subject: [PATCH] Added auto-update functionality

---
 RGB.NET.Core/RGB.NET.Core.csproj  |  2 +
 RGB.NET.Core/RGBSurfaceUpdater.cs | 89 +++++++++++++++++++++++++++++++
 RGB.NET.Core/UpdateMode.cs        | 18 +++++++
 3 files changed, 109 insertions(+)
 create mode 100644 RGB.NET.Core/RGBSurfaceUpdater.cs
 create mode 100644 RGB.NET.Core/UpdateMode.cs

diff --git a/RGB.NET.Core/RGB.NET.Core.csproj b/RGB.NET.Core/RGB.NET.Core.csproj
index f3dad45..db842ba 100644
--- a/RGB.NET.Core/RGB.NET.Core.csproj
+++ b/RGB.NET.Core/RGB.NET.Core.csproj
@@ -75,6 +75,8 @@
     <Compile Include="RGBSurface.cs" />
     <Compile Include="RGBSurfaceDeviceEvents.cs" />
     <Compile Include="RGBSurfaceDeviceLoader.cs" />
+    <Compile Include="RGBSurfaceUpdater.cs" />
+    <Compile Include="UpdateMode.cs" />
   </ItemGroup>
   <ItemGroup />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
diff --git a/RGB.NET.Core/RGBSurfaceUpdater.cs b/RGB.NET.Core/RGBSurfaceUpdater.cs
new file mode 100644
index 0000000..c040acc
--- /dev/null
+++ b/RGB.NET.Core/RGBSurfaceUpdater.cs
@@ -0,0 +1,89 @@
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace RGB.NET.Core
+{
+    public static partial class RGBSurface
+    {
+        #region Properties & Fields
+
+        private static CancellationTokenSource _updateTokenSource;
+        private static CancellationToken _updateToken;
+        private static Task _updateTask;
+
+        /// <summary>
+        /// Gets or sets the update-frequency in seconds. (Calculate by using '1.0 / updates per second')
+        /// </summary>
+        public static double UpdateFrequency { get; set; } = 1.0 / 30.0;
+
+        private static UpdateMode _updateMode = UpdateMode.Manual;
+        /// <summary>
+        /// Gets or sets the update-mode.
+        /// </summary>
+        public static UpdateMode UpdateMode
+        {
+            get { return _updateMode; }
+            set
+            {
+                _updateMode = value;
+                CheckUpdateLoop();
+            }
+        }
+
+        #endregion
+
+        #region Methods
+
+        /// <summary>
+        /// Checks if automatic updates should occur and starts/stops the update-loop if needed.
+        /// </summary>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown if the requested update-mode is not available.</exception>
+        private static async void CheckUpdateLoop()
+        {
+            bool shouldRun;
+            switch (UpdateMode)
+            {
+                case UpdateMode.Manual:
+                    shouldRun = false;
+                    break;
+                case UpdateMode.Continuous:
+                    shouldRun = true;
+                    break;
+                default:
+                    throw new ArgumentOutOfRangeException();
+            }
+
+            if (shouldRun && (_updateTask == null)) // Start task
+            {
+                _updateTokenSource?.Dispose();
+                _updateTokenSource = new CancellationTokenSource();
+                _updateTask = Task.Factory.StartNew(UpdateLoop, (_updateToken = _updateTokenSource.Token));
+            }
+            else if (!shouldRun && (_updateTask != null)) // Stop task
+            {
+                _updateTokenSource.Cancel();
+                await _updateTask;
+                _updateTask.Dispose();
+                _updateTask = null;
+            }
+        }
+
+        private static void UpdateLoop()
+        {
+            while (!_updateToken.IsCancellationRequested)
+            {
+                long preUpdateTicks = DateTime.Now.Ticks;
+
+                foreach (IRGBDevice device in _devices)
+                    device.Update();
+
+                int sleep = (int)((UpdateFrequency * 1000.0) - ((DateTime.Now.Ticks - preUpdateTicks) / 10000.0));
+                if (sleep > 0)
+                    Thread.Sleep(sleep);
+            }
+        }
+
+        #endregion
+    }
+}
diff --git a/RGB.NET.Core/UpdateMode.cs b/RGB.NET.Core/UpdateMode.cs
new file mode 100644
index 0000000..960a03b
--- /dev/null
+++ b/RGB.NET.Core/UpdateMode.cs
@@ -0,0 +1,18 @@
+namespace RGB.NET.Core
+{
+    /// <summary>
+    /// Contains list of available update modes.
+    /// </summary>
+    public enum UpdateMode
+    {
+        /// <summary>
+        /// The <see cref="RGBSurface"/> will not perform automatic updates. Updates will only occur if <see cref="RGBSurface.Update" /> is called.
+        /// </summary>
+        Manual,
+
+        /// <summary>
+        /// The <see cref="RGBSurface"/> will perform automatic updates at the rate set in <see cref="RGBSurface.UpdateFrequency" />.
+        /// </summary>
+        Continuous
+    }
+}