1 files changed, 198 insertions, 0 deletions
diff --git a/src/Ryujinx.Input/Assigner/GamepadButtonAssigner.cs b/src/Ryujinx.Input/Assigner/GamepadButtonAssigner.cs
new file mode 100644
index 00000000..8621b3a5
--- /dev/null
+++ b/src/Ryujinx.Input/Assigner/GamepadButtonAssigner.cs
@@ -0,0 +1,198 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+
+namespace Ryujinx.Input.Assigner
+{
+    /// <summary>
+    /// <see cref="IButtonAssigner"/> implementation for regular <see cref="IGamepad"/>.
+    /// </summary>
+    public class GamepadButtonAssigner : IButtonAssigner
+    {
+        private IGamepad _gamepad;
+
+        private GamepadStateSnapshot _currState;
+
+        private GamepadStateSnapshot _prevState;
+
+        private JoystickButtonDetector _detector;
+
+        private bool _forStick;
+
+        public GamepadButtonAssigner(IGamepad gamepad, float triggerThreshold, bool forStick)
+        {
+            _gamepad = gamepad;
+            _detector = new JoystickButtonDetector();
+            _forStick = forStick;
+
+            _gamepad?.SetTriggerThreshold(triggerThreshold);
+        }
+
+        public void Initialize()
+        {
+            if (_gamepad != null)
+            {
+                _currState = _gamepad.GetStateSnapshot();
+                _prevState = _currState;
+            }    
+        }
+
+        public void ReadInput()
+        {
+            if (_gamepad != null)
+            {
+                _prevState = _currState;
+                _currState = _gamepad.GetStateSnapshot();
+            }
+
+            CollectButtonStats();
+        }
+
+        public bool HasAnyButtonPressed()
+        {
+            return _detector.HasAnyButtonPressed();
+        }
+
+        public bool ShouldCancel()
+        {
+            return _gamepad == null || !_gamepad.IsConnected;
+        }
+
+        public string GetPressedButton()
+        {
+            IEnumerable<GamepadButtonInputId> pressedButtons = _detector.GetPressedButtons();
+
+            if (pressedButtons.Any())
+            {
+                return !_forStick ? pressedButtons.First().ToString() : ((StickInputId)pressedButtons.First()).ToString();
+            }
+
+            return "";
+        }
+
+        private void CollectButtonStats()
+        {
+            if (_forStick)
+            {
+                for (StickInputId inputId = StickInputId.Left; inputId < StickInputId.Count; inputId++)
+                {
+                    (float x, float y) = _currState.GetStick(inputId);
+
+                    float value;
+
+                    if (x != 0.0f)
+                    {
+                        value = x;
+                    }
+                    else if (y != 0.0f)
+                    {
+                        value = y;
+                    }
+                    else
+                    {
+                        continue;
+                    }
+
+                    _detector.AddInput((GamepadButtonInputId)inputId, value);
+                }
+            }
+            else
+            {
+                for (GamepadButtonInputId inputId = GamepadButtonInputId.A; inputId < GamepadButtonInputId.Count; inputId++)
+                {
+                    if (_currState.IsPressed(inputId) && !_prevState.IsPressed(inputId))
+                    {
+                        _detector.AddInput(inputId, 1);
+                    }
+
+                    if (!_currState.IsPressed(inputId) && _prevState.IsPressed(inputId))
+                    {
+                        _detector.AddInput(inputId, -1);
+                    }
+                }
+            }
+        }
+
+        private class JoystickButtonDetector
+        {
+            private Dictionary<GamepadButtonInputId, InputSummary> _stats;
+
+            public JoystickButtonDetector()
+            {
+                _stats = new Dictionary<GamepadButtonInputId, InputSummary>();
+            }
+
+            public bool HasAnyButtonPressed()
+            {
+                return _stats.Values.Any(CheckButtonPressed);
+            }
+
+            public IEnumerable<GamepadButtonInputId> GetPressedButtons()
+            {
+                return _stats.Where(kvp => CheckButtonPressed(kvp.Value)).Select(kvp => kvp.Key);
+            }
+
+            public void AddInput(GamepadButtonInputId button, float value)
+            {
+                InputSummary inputSummary;
+
+                if (!_stats.TryGetValue(button, out inputSummary))
+                {
+                    inputSummary = new InputSummary();
+                    _stats.Add(button, inputSummary);
+                }
+
+                inputSummary.AddInput(value);
+            }
+
+            public override string ToString()
+            {
+                StringWriter writer = new StringWriter();
+
+                foreach (var kvp in _stats)
+                {
+                    writer.WriteLine($"Button {kvp.Key} -> {kvp.Value}");
+                }
+
+                return writer.ToString();
+            }
+
+            private bool CheckButtonPressed(InputSummary sequence)
+            {
+                float distance = Math.Abs(sequence.Min - sequence.Avg) + Math.Abs(sequence.Max - sequence.Avg);
+                return distance > 1.5; // distance range [0, 2]
+            }
+        }
+
+        private class InputSummary
+        {
+            public float Min, Max, Sum, Avg;
+
+            public int NumSamples;
+
+            public InputSummary()
+            {
+                Min = float.MaxValue;
+                Max = float.MinValue;
+                Sum = 0;
+                NumSamples = 0;
+                Avg = 0;
+            }
+
+            public void AddInput(float value)
+            {
+                Min = Math.Min(Min, value);
+                Max = Math.Max(Max, value);
+                Sum += value;
+                NumSamples += 1;
+                Avg = Sum / NumSamples;
+            }
+
+            public override string ToString()
+            {
+                return $"Avg: {Avg} Min: {Min} Max: {Max} Sum: {Sum} NumSamples: {NumSamples}";
+            }
+        }
+    }
+}