XInputGamepadAdapter.cs

using Gondwana.Input.Gamepad;
using static Gondwana.WinForms.Input.Gamepad.XInput.XInput;
 
namespace Gondwana.WinForms.Input.Gamepad.XInput;

public sealed class XInputGamepadAdapter : IGamepadAdapter
{
    private readonly int _controllerIndex;
    private readonly HashSet<string> _pressedButtons = new();

    public string GamepadId { get; }

    public IReadOnlyCollection<string> PressedButtons => _pressedButtons;

    public GamepadStickState? LeftStick { get; private set; }

    public GamepadStickState? RightStick { get; private set; }

    public float LeftTrigger { get; private set; }

    public float RightTrigger { get; private set; }

    public XInputGamepadAdapter(int controllerIndex = 0)
    {
        _controllerIndex = controllerIndex;
        GamepadId = $"XInput_{controllerIndex}";
    }

    internal void Poll()
    {
        _pressedButtons.Clear();
 
        if (GetState(_controllerIndex, out var state) != 0)
        {
            ClearState();
            return;
        }
 
        ApplyState(state.Gamepad);
    }

    internal void ClearState()
    {
        _pressedButtons.Clear();
        LeftStick = null;
        RightStick = null;
        LeftTrigger = 0f;
        RightTrigger = 0f;
    }

    internal void ApplyState(XINPUT_GAMEPAD gamepad)
    {
        _pressedButtons.Clear();
 
        LeftStick = GamepadStickState.FromRaw16(gamepad.sThumbLX, gamepad.sThumbLY);
        RightStick = GamepadStickState.FromRaw16(gamepad.sThumbRX, gamepad.sThumbRY);
        LeftTrigger = gamepad.bLeftTrigger / 255f;
        RightTrigger = gamepad.bRightTrigger / 255f;
 
        var buttons = (XInputButtons)gamepad.wButtons;
        foreach (XInputButtons button in Enum.GetValues<XInputButtons>())
        {
            if ((buttons & button) != 0)
                _pressedButtons.Add(button.ToString());
        }
 
        if (LeftTrigger > 0.5f)
            _pressedButtons.Add("LeftTrigger");
 
        if (RightTrigger > 0.5f)
            _pressedButtons.Add("RightTrigger");
    }
}