Keyboard-Calculator/NumpadMonitor/KeyInfo.cs

using Newtonsoft.Json;
using System;
using System.Text;
using System.Windows.Forms;

namespace NumpadMonitor
{
    public class KeyInfo
    {
        public Keys Key { get; private set; }
        public int FsModifiers { get; private set; }
        public IntPtr KeyCode { get; private set; }

        internal void SetKeyCode(IntPtr keyCode)
        {
            if (KeyCode == IntPtr.Zero)
                KeyCode = keyCode;
            else
                throw new ArgumentException("Parameter was already set, and cannot be set again");
        }

        public KeyInfo(Keys key, int fsModifiers = 0)
        {
            Key = key;
            FsModifiers = fsModifiers;
        }

        [JsonConstructor]
        public KeyInfo(Keys key, int fsModifiers, IntPtr keyCode)
        {
            Key = key;
            FsModifiers = fsModifiers;
            KeyCode = keyCode;
        }

        public static int GetModifierInt(Modifier[] modifiers)
        {
            int modifierCode = 0;
            foreach (Modifier modifier in modifiers)
            {
                switch (modifier)
                {
                    case Modifier.Alt:
                        modifierCode |= 0b0001;
                        break;

                    case Modifier.Ctrl:
                        modifierCode |= 0b0010;
                        break;

                    case Modifier.Shift:
                        modifierCode |= 0b0100;
                        break;

                    case Modifier.Win:
                        modifierCode |= 0b1000;
                        break;

                    default:
                        throw new ArgumentOutOfRangeException("modifier", "Modifier not in enum");
                }
            }
            return modifierCode;
        }

        public override string ToString()
        {
            StringBuilder sb = new StringBuilder();
            if (FsModifiers != 0)
            {
                if ((FsModifiers & 0b0010) == 0b0010)
                    sb.Append("Ctrl + ");
                if ((FsModifiers & 0b0001) == 0b0001)
                    sb.Append("Alt + ");
                if ((FsModifiers & 0b0100) == 0b0100)
                    sb.Append("Shift + ");
                if ((FsModifiers & 0b1000) == 0b1000)
                    sb.Append("Win + ");
            }
            sb.Append(Key.ToString());
            return sb.ToString();
        }

        public override bool Equals(object obj)
        {
            return obj is KeyInfo info &&
                   Key == info.Key &&
                   FsModifiers == info.FsModifiers;
        }

        public override int GetHashCode()
        {
            int hash = 17;
            hash = hash * 23 + (int)Key;
            hash = hash * 23 + FsModifiers;
            return hash;
        }
    }

    public enum Modifier
    {
        Alt,
        Ctrl,
        Shift,
        Win
    }
}