public interface IPlayer
{
    void Initialize(Piece piece);

    void Terminate();

    Position? GetNextPosition(IBoard board);
}

public class SimplePlayer : IPlayer
{
    Piece Piece { get; set; }

    #region IPlayer メンバ

    public void Initialize(Piece piece)
    {
        this.Piece = piece;
    }

    public void Terminate()
    {
        // 何もしない
    }

    public Position? GetNextPosition(IBoard board)
    {
        var cell = board.Cells.FirstOrDefault(x => board.Cells.CanPut(x.Position, this.Piece));
        return (cell == null) ? default(Position?) : cell.Position;
    }

    #endregion
}

using System;
using System.ComponentModel;
using System.Collections.Generic;
using System.Diagnostics;
using System.Text;

using System.Drawing;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace jp.hidori.Windows.Forms
{
    public class LowLevelMouseHook : Component
    {
        #region 8d\92z

        /// <summary>
        /// 83N838983X82cc90V8bK83C839383X83^839383X82f08f898afa89bb82b582dc82b781B
        /// </summary>
        public LowLevelMouseHook()
        {
            InitializeComponent();

            this.Initialize();
        }

        /// <summary>
        /// 83N838983X82cc90V8bK83C839383X83^839383X82f08f898afa89bb82b582dc82b781B
        /// </summary>
        /// <param name="container">83R839383e83i82f095\82b7IContainer81B</param>
        public LowLevelMouseHook(IContainer container)
        {
            container.Add(this);

            InitializeComponent();

            this.Initialize();
        }

        #endregion

        #region 83R839383|81[83l839383g83f83U83C83i82c590b690ac82b382ea82bd83R81[83h

        /// <summary>
        /// 95K97v82c883f83U83C83i95cf909482c582b781B
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// 8eg97p928682cc838a83\81[83X82f082b782d782c483N838a81[839383A83b83v82b582dc82b781B
        /// </summary>
        /// <param name="disposing">83}83l81[83W838a83\81[83X82aa94j8afc82b382ea82e98fea8d87true81A94j8afc82b382ea82c882a28fea8d8782cdfalse 82c582b781B</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        /// <summary>
        /// 83f83U83C83i83T83|81[83g82c995K97v82c8838183\83b83h82c582b781B82b182cc838183\83b83h82cc93e097e82f0
        /// 83R81[83h83G83f83B83^82c595cf8dX82b582c882a282c582ad82be82b382a281B
        /// </summary>
        private void InitializeComponent()
        {
            components = new System.ComponentModel.Container();
        }

        #endregion

        #region P/INVOKE

        private enum WM_ : int
        {
            WM_MOUSEMOVE = 0x0200,
            WM_LBUTTONDOWN = 0x0201,
            WM_LBUTTONUP = 0x0202,
            WM_RBUTTONDOWN = 0x0204,
            WM_RBUTTONUP = 0x0205,
            WM_MBUTTONDOWN = 0x0207,
            WM_MBUTTONUP = 0x0208,
            WM_MOUSEWHEEL = 0x020A,
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct MSLLHOOKSTRUCT
        {
            public Point pt;
            public int mouseData;
            public int flags;
            public int time;
            public IntPtr dwExtraInfo;
        }

        [DllImport("Kernel32", SetLastError = true)]
        private static extern IntPtr GetModuleHandle(string moduleName);

        private delegate IntPtr HookProc(int code, IntPtr wParam, IntPtr lParam);

        private static readonly int WH_MOUSE_LL = 14;

        private static readonly int HC_ACTION = 0;

        [DllImport("User32", SetLastError = true)]
        private static extern IntPtr SetWindowsHookEx(int id, HookProc lpfn, IntPtr hmod, int threadId);

        [DllImport("User32", SetLastError = true)]
        private static extern bool UnhookWindowsHookEx(IntPtr hhk);

        [DllImport("User32", SetLastError = true)]
        private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);

        #endregion

        #region 83t83B81[838b83h

        private IntPtr hhk = IntPtr.Zero;

        private HookProc lowLevelMouseHookProc;

        #endregion

        #region 83v838d83p83e83B

        private bool _Enabled = false;

        /// <summary>
        /// 83t83b83N82aa90dd92e882b382ea82c482a282e982a982c782a482a982f08ee693be82dc82bd82cd90dd92e882b582dc82b781B
        /// </summary>
        [DefaultValue(false)]
        public bool Enabled
        {
            get { return _Enabled; }
            set
            {
                if (_Enabled != value)
                {
                    if (value)
                    {
                        this.AddHook();
                    }
                    else
                    {
                        this.RemoveHook();
                    }

                    _Enabled = value;
                }
            }
        }

        #endregion

        #region 83C83x839383g

        /// <summary>
        /// 83}83E83X83{83^839382aa83N838a83b83N82b382ea82e982c694ad90b682b582dc82b781B
        /// </summary>
        public event MouseEventHandler MouseDown;

        protected virtual void OnMouseDown(MouseEventArgs e)
        {
            if (this.MouseDown != null)
            {
                this.MouseDown(this, e);
            }
        }

        /// <summary>
        /// 83}83E83X83{83^839382aa97a382b382ea82e982c694ad90b682b582dc82b781B
        /// </summary>
        public event MouseEventHandler MouseUp;

        protected virtual void OnMouseUp(MouseEventArgs e)
        {
            if (this.MouseUp != null)
            {
                this.MouseUp(this, e);
            }
        }

        /// <summary>
        /// 83}83E83X83|83C839383^82aa88da93ae82b782e982c694ad90b682b582dc82b781B
        /// </summary>
        public event MouseEventHandler MouseMove;

        protected virtual void OnMouseMove(MouseEventArgs e)
        {
            if (this.MouseMove != null)
            {
                this.MouseMove(this, e);
            }
        }

        /// <summary>
        /// 83}83E83X83z83C81[838b82aa93ae82ad82c694ad90b682b582dc82b781B
        /// </summary>
        public event MouseEventHandler MouseWheel;

        protected virtual void OnMouseWheel(MouseEventArgs e)
        {
            if (this.MouseWheel != null)
            {
                this.MouseWheel(this, e);
            }
        }

        #endregion

        #region 91808dec

        /// <summary>
        /// 83t83b83N82f090dd92e882b582dc82b781B
        /// </summary>
        public void Start()
        {
            this.Enabled = true;
        }

        /// <summary>
        /// 83t83b83N82f089f08f9c82b582dc82b781B
        /// </summary>
        public void Stop()
        {
            this.Enabled = false;
        }

        #endregion

        #region 8ec09195

        private void Initialize()
        {
            this.lowLevelMouseHookProc = this.LowLevelMouseHookProc;
        }

        private void AddHook()
        {
            if (this.hhk != IntPtr.Zero) return;

            this.hhk = SetWindowsHookEx(WH_MOUSE_LL, this.lowLevelMouseHookProc, GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), 0);
        }

        private void RemoveHook()
        {
            if (this.hhk == IntPtr.Zero) return;

            IntPtr hhk = this.hhk;
            this.hhk = IntPtr.Zero;

            UnhookWindowsHookEx(hhk);
        }

        private IntPtr LowLevelMouseHookProc(int code, IntPtr wParam, IntPtr lParam)
        {
            if (code == HC_ACTION)
            {
                MSLLHOOKSTRUCT msll = (MSLLHOOKSTRUCT)Marshal.PtrToStructure(lParam, typeof(MSLLHOOKSTRUCT));

                switch (wParam.ToInt32())
                {
                case (int)WM_.WM_MOUSEMOVE:
                    this.OnMouseMove(new MouseEventArgs(MouseButtons.None, 0, msll.pt.X, msll.pt.Y, 0));
                    break;

                case (int)WM_.WM_LBUTTONDOWN:
                    this.OnMouseDown(new MouseEventArgs(MouseButtons.Left, 1, msll.pt.X, msll.pt.Y, 0));
                    break;

                case (int)WM_.WM_LBUTTONUP:
                    this.OnMouseUp(new MouseEventArgs(MouseButtons.Left, 1, msll.pt.X, msll.pt.Y, 0));
                    break;

                case (int)WM_.WM_RBUTTONDOWN:
                    this.OnMouseDown(new MouseEventArgs(MouseButtons.Right, 1, msll.pt.X, msll.pt.Y, 0));
                    break;

                case (int)WM_.WM_RBUTTONUP:
                    this.OnMouseUp(new MouseEventArgs(MouseButtons.Right, 1, msll.pt.X, msll.pt.Y, 0));
                    break;

                case (int)WM_.WM_MBUTTONDOWN:
                    this.OnMouseDown(new MouseEventArgs(MouseButtons.Middle, 1, msll.pt.X, msll.pt.Y, 0));
                    break;

                case (int)WM_.WM_MBUTTONUP:
                    this.OnMouseUp(new MouseEventArgs(MouseButtons.Middle, 1, msll.pt.X, msll.pt.Y, 0));
                    break;

                case (int)WM_.WM_MOUSEWHEEL:
                    this.OnMouseDown(new MouseEventArgs(MouseButtons.None, 0, msll.pt.X, msll.pt.Y, (int)(short)HighValue((uint)msll.mouseData)));
                    break;
                }
            }

            return LowLevelMouseHook.CallNextHookEx(this.hhk, code, wParam, lParam);
        }

        private static ushort HighValue(uint value)
        {
            return (ushort)((value >> 16) & 0x0ffff);
        }

        #endregion
    }
}