UnityExplorer/src/Input/InputSystem.cs

using System;
using System.Reflection;
using UnityExplorer.Helpers;
using UnityEngine;

namespace UnityExplorer.Input
{
    public class InputSystem : IHandleInput
    {
        public InputSystem()
        {
            ExplorerCore.Log("Initializing new InputSystem support...");

            m_kbCurrentProp = TKeyboard.GetProperty("current");
            m_kbIndexer = TKeyboard.GetProperty("Item", new Type[] { TKey });

            var btnControl = ReflectionHelpers.GetTypeByName("UnityEngine.InputSystem.Controls.ButtonControl");
            m_btnIsPressedProp = btnControl.GetProperty("isPressed");
            m_btnWasPressedProp = btnControl.GetProperty("wasPressedThisFrame");

            m_mouseCurrentProp = TMouse.GetProperty("current");
            m_leftButtonProp = TMouse.GetProperty("leftButton");
            m_rightButtonProp = TMouse.GetProperty("rightButton");

            m_positionProp = ReflectionHelpers.GetTypeByName("UnityEngine.InputSystem.Pointer")
                            .GetProperty("position");

            m_readVector2InputMethod = ReflectionHelpers.GetTypeByName("UnityEngine.InputSystem.InputControl`1")
                                      .MakeGenericType(typeof(Vector2))
                                      .GetMethod("ReadValue");
        }

        public static Type TKeyboard => m_tKeyboard ?? (m_tKeyboard = ReflectionHelpers.GetTypeByName("UnityEngine.InputSystem.Keyboard"));
        private static Type m_tKeyboard;

        public static Type TMouse => m_tMouse ?? (m_tMouse = ReflectionHelpers.GetTypeByName("UnityEngine.InputSystem.Mouse"));
        private static Type m_tMouse;

        public static Type TKey => m_tKey ?? (m_tKey = ReflectionHelpers.GetTypeByName("UnityEngine.InputSystem.Key"));
        private static Type m_tKey;

        private static PropertyInfo m_btnIsPressedProp;
        private static PropertyInfo m_btnWasPressedProp;

        private static object CurrentKeyboard => m_currentKeyboard ?? (m_currentKeyboard = m_kbCurrentProp.GetValue(null, null));
        private static object m_currentKeyboard;
        private static PropertyInfo m_kbCurrentProp;
        private static PropertyInfo m_kbIndexer;

        private static object CurrentMouse => m_currentMouse ?? (m_currentMouse = m_mouseCurrentProp.GetValue(null, null));
        private static object m_currentMouse;
        private static PropertyInfo m_mouseCurrentProp;

        private static object LeftMouseButton => m_lmb ?? (m_lmb = m_leftButtonProp.GetValue(CurrentMouse, null));
        private static object m_lmb;
        private static PropertyInfo m_leftButtonProp;

        private static object RightMouseButton => m_rmb ?? (m_rmb = m_rightButtonProp.GetValue(CurrentMouse, null));
        private static object m_rmb;
        private static PropertyInfo m_rightButtonProp;

        private static object MousePositionInfo => m_pos ?? (m_pos = m_positionProp.GetValue(CurrentMouse, null));
        private static object m_pos;
        private static PropertyInfo m_positionProp;
        private static MethodInfo m_readVector2InputMethod;

        public Vector2 MousePosition => (Vector2)m_readVector2InputMethod.Invoke(MousePositionInfo, new object[0]);

        public bool GetKeyDown(KeyCode key)
        {
            var parsedKey = Enum.Parse(TKey, key.ToString());
            var actualKey = m_kbIndexer.GetValue(CurrentKeyboard, new object[] { parsedKey });

            return (bool)m_btnWasPressedProp.GetValue(actualKey, null);
        }

        public bool GetKey(KeyCode key)
        {
            var parsed = Enum.Parse(TKey, key.ToString());
            var actualKey = m_kbIndexer.GetValue(CurrentKeyboard, new object[] { parsed });

            return (bool)m_btnIsPressedProp.GetValue(actualKey, null);
        }

        public bool GetMouseButtonDown(int btn)
        {
            switch (btn)
            {
                case 0: return (bool)m_btnWasPressedProp.GetValue(LeftMouseButton, null);
                case 1: return (bool)m_btnWasPressedProp.GetValue(RightMouseButton, null);
                // case 2: return (bool)_btnWasPressedProp.GetValue(MiddleMouseButton, null);
                default: throw new NotImplementedException();
            }
        }

        public bool GetMouseButton(int btn)
        {
            switch (btn)
            {
                case 0: return (bool)m_btnIsPressedProp.GetValue(LeftMouseButton, null);
                case 1: return (bool)m_btnIsPressedProp.GetValue(RightMouseButton, null);
                // case 2: return (bool)_btnIsPressedProp.GetValue(MiddleMouseButton, null);
                default: throw new NotImplementedException();
            }
        }
    }
}