1 files changed, 74 insertions, 0 deletions
diff --git a/src/SMAPI/Framework/Input/MouseStateBuilder.cs b/src/SMAPI/Framework/Input/MouseStateBuilder.cs
new file mode 100644
index 00000000..9c6f6f95
--- /dev/null
+++ b/src/SMAPI/Framework/Input/MouseStateBuilder.cs
@@ -0,0 +1,74 @@
+using System.Collections.Generic;
+using Microsoft.Xna.Framework.Input;
+
+namespace StardewModdingAPI.Framework.Input
+{
+    /// <summary>Manipulates mouse state.</summary>
+    internal class MouseStateBuilder
+    {
+        /*********
+        ** Fields
+        *********/
+        /// <summary>The current button states.</summary>
+        private readonly IDictionary<SButton, ButtonState> ButtonStates;
+
+        /// <summary>The X cursor position.</summary>
+        private readonly int X;
+
+        /// <summary>The Y cursor position.</summary>
+        private readonly int Y;
+
+        /// <summary>The mouse wheel scroll value.</summary>
+        private readonly int ScrollWheelValue;
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="state">The initial state.</param>
+        public MouseStateBuilder(MouseState state)
+        {
+            this.ButtonStates = new Dictionary<SButton, ButtonState>
+            {
+                [SButton.MouseLeft] = state.LeftButton,
+                [SButton.MouseMiddle] = state.MiddleButton,
+                [SButton.MouseRight] = state.RightButton,
+                [SButton.MouseX1] = state.XButton1,
+                [SButton.MouseX2] = state.XButton2
+            };
+            this.X = state.X;
+            this.Y = state.Y;
+            this.ScrollWheelValue = state.ScrollWheelValue;
+        }
+
+        /// <summary>Override the states for a set of buttons.</summary>
+        /// <param name="overrides">The button state overrides.</param>
+        public MouseStateBuilder OverrideButtons(IDictionary<SButton, SButtonState> overrides)
+        {
+            foreach (var pair in overrides)
+            {
+                bool isDown = pair.Value.IsDown();
+                if (this.ButtonStates.ContainsKey(pair.Key))
+                    this.ButtonStates[pair.Key] = isDown ? ButtonState.Pressed : ButtonState.Released;
+            }
+
+            return this;
+        }
+
+        /// <summary>Construct an equivalent mouse state.</summary>
+        public MouseState ToMouseState()
+        {
+            return new MouseState(
+                x: this.X,
+                y: this.Y,
+                scrollWheel: this.ScrollWheelValue,
+                leftButton: this.ButtonStates[SButton.MouseLeft],
+                middleButton: this.ButtonStates[SButton.MouseMiddle],
+                rightButton: this.ButtonStates[SButton.MouseRight],
+                xButton1: this.ButtonStates[SButton.MouseX1],
+                xButton2: this.ButtonStates[SButton.MouseX2]
+            );
+        }
+    }
+}