add Input.ButtonsChanged event (#744)

5 files changed, 99 insertions, 13 deletions

diff --git a/src/SMAPI/Events/ButtonsChangedEventArgs.cs b/src/SMAPI/Events/ButtonsChangedEventArgs.cs
new file mode 100644
index 00000000..dda41692
--- /dev/null
+++ b/src/SMAPI/Events/ButtonsChangedEventArgs.cs
@@ -0,0 +1,67 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using StardewModdingAPI.Framework.Input;
+
+namespace StardewModdingAPI.Events
+{
+    /// <summary>Event arguments when any buttons were pressed or released.</summary>
+    public class ButtonsChangedEventArgs : EventArgs
+    {
+        /*********
+        ** Fields
+        *********/
+        /// <summary>The buttons that were pressed, held, or released since the previous tick.</summary>
+        private readonly Lazy<Dictionary<SButtonState, SButton[]>> ButtonsByState;
+
+
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>The current cursor position.</summary>
+        public ICursorPosition Cursor { get; }
+
+        /// <summary>The buttons which were pressed since the previous tick.</summary>
+        public IEnumerable<SButton> Pressed => this.ButtonsByState.Value[SButtonState.Pressed];
+
+        /// <summary>The buttons which were held since the previous tick.</summary>
+        public IEnumerable<SButton> Held => this.ButtonsByState.Value[SButtonState.Held];
+
+        /// <summary>The buttons which were released since the previous tick.</summary>
+        public IEnumerable<SButton> Released => this.ButtonsByState.Value[SButtonState.Released];
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="cursor">The cursor position.</param>
+        /// <param name="inputState">The game's current input state.</param>
+        internal ButtonsChangedEventArgs(ICursorPosition cursor, SInputState inputState)
+        {
+            this.Cursor = cursor;
+            this.ButtonsByState = new Lazy<Dictionary<SButtonState, SButton[]>>(() => this.GetButtonsByState(inputState));
+        }
+
+
+        /*********
+        ** Private methods
+        *********/
+        /// <summary>Get the buttons that were pressed, held, or released since the previous tick.</summary>
+        /// <param name="inputState">The game's current input state.</param>
+        private Dictionary<SButtonState, SButton[]> GetButtonsByState(SInputState inputState)
+        {
+            Dictionary<SButtonState, SButton[]> lookup = inputState.ButtonStates
+                .GroupBy(p => p.Value)
+                .ToDictionary(p => p.Key, p => p.Select(p => p.Key).ToArray());
+
+            foreach (var state in new[] { SButtonState.Pressed, SButtonState.Held, SButtonState.Released })
+            {
+                if (!lookup.ContainsKey(state))
+                    lookup[state] = new SButton[0];
+            }
+
+            return lookup;
+        }
+    }
+}
diff --git a/src/SMAPI/Events/IInputEvents.cs b/src/SMAPI/Events/IInputEvents.cs
index 5c40a438..081c40c0 100644
--- a/src/SMAPI/Events/IInputEvents.cs
+++ b/src/SMAPI/Events/IInputEvents.cs
@@ -5,6 +5,9 @@ namespace StardewModdingAPI.Events
     /// <summary>Events raised when the player provides input using a controller, keyboard, or mouse.</summary>
     public interface IInputEvents
     {
+        /// <summary>Raised after the player presses or releases any buttons on the keyboard, controller, or mouse.</summary>
+        event EventHandler<ButtonsChangedEventArgs> ButtonsChanged;
+
         /// <summary>Raised after the player presses a button on the keyboard, controller, or mouse.</summary>
         event EventHandler<ButtonPressedEventArgs> ButtonPressed;
 
diff --git a/src/SMAPI/Framework/Events/EventManager.cs b/src/SMAPI/Framework/Events/EventManager.cs
index 665dbfe3..f4abfffe 100644
--- a/src/SMAPI/Framework/Events/EventManager.cs
+++ b/src/SMAPI/Framework/Events/EventManager.cs
@@ -93,6 +93,9 @@ namespace StardewModdingAPI.Framework.Events
         /****
         ** Input
         ****/
+        /// <summary>Raised after the player presses or releases any buttons on the keyboard, controller, or mouse.</summary>
+        public readonly ManagedEvent<ButtonsChangedEventArgs> ButtonsChanged;
+
         /// <summary>Raised after the player presses a button on the keyboard, controller, or mouse.</summary>
         public readonly ManagedEvent<ButtonPressedEventArgs> ButtonPressed;
 
@@ -212,6 +215,7 @@ namespace StardewModdingAPI.Framework.Events
             this.TimeChanged = ManageEventOf<TimeChangedEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.TimeChanged));
             this.ReturnedToTitle = ManageEventOf<ReturnedToTitleEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.ReturnedToTitle));
 
+            this.ButtonsChanged = ManageEventOf<ButtonsChangedEventArgs>(nameof(IModEvents.Input), nameof(IInputEvents.ButtonsChanged));
             this.ButtonPressed = ManageEventOf<ButtonPressedEventArgs>(nameof(IModEvents.Input), nameof(IInputEvents.ButtonPressed));
             this.ButtonReleased = ManageEventOf<ButtonReleasedEventArgs>(nameof(IModEvents.Input), nameof(IInputEvents.ButtonReleased));
             this.CursorMoved = ManageEventOf<CursorMovedEventArgs>(nameof(IModEvents.Input), nameof(IInputEvents.CursorMoved), isPerformanceCritical: true);
diff --git a/src/SMAPI/Framework/Events/ModInputEvents.cs b/src/SMAPI/Framework/Events/ModInputEvents.cs
index ab26ab3e..6f423e5d 100644
--- a/src/SMAPI/Framework/Events/ModInputEvents.cs
+++ b/src/SMAPI/Framework/Events/ModInputEvents.cs
@@ -9,6 +9,13 @@ namespace StardewModdingAPI.Framework.Events
         /*********
         ** Accessors
         *********/
+        /// <summary>Raised after the player presses or releases any buttons on the keyboard, controller, or mouse.</summary>
+        public event EventHandler<ButtonsChangedEventArgs> ButtonsChanged
+        {
+            add => this.EventManager.ButtonsChanged.Add(value, this.Mod);
+            remove => this.EventManager.ButtonsChanged.Remove(value);
+        }
+
         /// <summary>Raised after the player presses a button on the keyboard, controller, or mouse.</summary>
         public event EventHandler<ButtonPressedEventArgs> ButtonPressed
         {
diff --git a/src/SMAPI/Framework/SCore.cs b/src/SMAPI/Framework/SCore.cs
index 0c55164c..1ac361cd 100644
--- a/src/SMAPI/Framework/SCore.cs
+++ b/src/SMAPI/Framework/SCore.cs
@@ -817,24 +817,29 @@ namespace StardewModdingAPI.Framework
                             }
 
                             // raise input button events
-                            foreach (var pair in inputState.ButtonStates)
+                            if (inputState.ButtonStates.Count > 0)
                             {
-                                SButton button = pair.Key;
-                                SButtonState status = pair.Value;
+                                events.ButtonsChanged.Raise(new ButtonsChangedEventArgs(cursor, inputState));
 
-                                if (status == SButtonState.Pressed)
+                                foreach (var pair in inputState.ButtonStates)
                                 {
-                                    if (this.Monitor.IsVerbose)
-                                        this.Monitor.Log($"Events: button {button} pressed.");
+                                    SButton button = pair.Key;
+                                    SButtonState status = pair.Value;
 
-                                    events.ButtonPressed.Raise(new ButtonPressedEventArgs(button, cursor, inputState));
-                                }
-                                else if (status == SButtonState.Released)
-                                {
-                                    if (this.Monitor.IsVerbose)
-                                        this.Monitor.Log($"Events: button {button} released.");
+                                    if (status == SButtonState.Pressed)
+                                    {
+                                        if (this.Monitor.IsVerbose)
+                                            this.Monitor.Log($"Events: button {button} pressed.");
 
-                                    events.ButtonReleased.Raise(new ButtonReleasedEventArgs(button, cursor, inputState));
+                                        events.ButtonPressed.Raise(new ButtonPressedEventArgs(button, cursor, inputState));
+                                    }
+                                    else if (status == SButtonState.Released)
+                                    {
+                                        if (this.Monitor.IsVerbose)
+                                            this.Monitor.Log($"Events: button {button} released.");
+
+                                        events.ButtonReleased.Raise(new ButtonReleasedEventArgs(button, cursor, inputState));
+                                    }
                                 }
                             }
                         }