/// <summary>
/// Human VS PC
/// </summary>
/// <param name="board"></param>
public void StartGameWithHuman(Board board)
{
int countmovesforDraw = 0;
var humanColor = Player.None;
var pcColor = Player.None;
bool firstTurn = true;
var rule = new Rules();
var print = new PrintBoardState();
while (true)
{
//first turn is always the human's
Console.WriteLine("Your turn, please enter a move in format 'from cell number' 'to cell number'");
HumanTurn:
bool capMove = false;
var input = Console.ReadLine();
IList<Coordinate> coords = ParseStrToCoords(input, board);
//If there is no input
if (coords == null)
{
Console.WriteLine("Wrong Input, please try again");
goto HumanTurn;
}
var srcCoord = coords.First();
var destCoord = coords.Last();
if (firstTurn)
{
humanColor = board.GetPlayer(srcCoord);
pcColor = board.GetOpponent(humanColor);
firstTurn = false;
}
//if select coordinate is not your coordinate then show error message
else if (humanColor != board.GetPlayer(srcCoord))
{
Console.WriteLine(
"This is not your piece , please enter cell number which allocated with your piece color");
goto HumanTurn;
}
//Fins captures
IDictionary<IList<Coordinate>, IList<Coordinate>> capturesAvailable = rule.FindCaptures(board,
humanColor);
//if there are any captures
if (capturesAvailable.Count > 0)
{
//check if they are contained in captured dictionary by looking on source and destination
IList<Coordinate> captures = rule.MapContainsCoords(capturesAvailable, srcCoord, destCoord);
//id they are not contained show error message
if (captures.Count == 0)
{
Console.WriteLine("You must capture maximum opponent soldiers on board");
goto HumanTurn;
}
else
{
//if there are captures and source and destination are corrrect, update board with move and captures
foreach (var coordinate in captures)
{
board[coordinate.X, coordinate.Y].Status = Piece.None;
board.UpdateCapturedSoldiers(coordinate, pcColor);
capMove = true;
}
}
}
//update board
if (capMove || rule.IsValidMove(board, srcCoord, destCoord, humanColor))
{
board.UpdateBoard(srcCoord, destCoord);
rule.IsBecameAKing(board, board[destCoord.X, destCoord.Y]);
print.DrawBoard(board);
}
else
{
Console.WriteLine("This is not a valid move, please enter again");
goto HumanTurn;
}
//check if game is finish by checking if players draw,lost or won
GameState game = GetGameState(humanColor, board);
if (GameState.Draw == CheckDraw(board, board[destCoord.X, destCoord.Y], capMove, ref countmovesforDraw))
{
Console.WriteLine("Draw");
break;
}
if (game == GameState.Lost)
{
Console.WriteLine("{0} Lost the game and {1} won", humanColor.ToString(), pcColor.ToString());
break;
}
if (game == GameState.Won)
{
Console.WriteLine("{0} Won", humanColor.ToString());
break;
}
//switch to opponent (PC)
ShowPlayerChange(pcColor);
var alphaBeta = new Alphabeta();
Board temp = new Board();
IList<Coordinate> tempCaptures = new List<Coordinate>();
//Define depth
int depth = rule.DefineDepth(board);
//Calling alpha-beta algorithm which return the best move in addition, return source,destination coordinates and a list of captures
alphaBeta.AlphaBeta(board, depth, Int32.MinValue, Int32.MaxValue, pcColor, true, ref srcCoord,
ref destCoord, ref temp, ref tempCaptures);
//Verify the move is in bounds, if yes update the board with it
if ((rule.InBounds(board, srcCoord.X, srcCoord.Y)) && (rule.InBounds(board, destCoord.X, destCoord.Y)))
{
board = temp.Copy();
print.DrawBoard(board);
}
// check if there were any captures. if yes check for draw
bool pcCaptured = tempCaptures.Count > 0;
//check if game was determined
game = GetGameState(humanColor, board);
if (GameState.Draw ==
CheckDraw(board, board[destCoord.X, destCoord.Y], pcCaptured, ref countmovesforDraw))
{
Console.WriteLine("Draw");
break;
}
if (game == GameState.Lost)
{
Console.WriteLine("{0} Lost the game and {1} won", humanColor.ToString(), pcColor.ToString());
break;
}
if (game == GameState.Won)
{
Console.WriteLine("{0} Won", humanColor.ToString());
break;
}
}
}
/// <summary>
/// alpha beta algorithm
/// boardcoordlist- each item in this map contains a new board (representing a new state) and a list of 2 coords representing the move that brought to this new state
/// mapBoardSrcDestCap- each item in this map contains the new board and source- dest coords (like above) and a list of captured coordinate (in case the new board is a result of a capture)
/// </summary>
/// <param name="board"></param>
/// <param name="depth"></param>
/// <param name="alpha"></param>
/// <param name="beta"></param>
/// <param name="player"></param>
/// <param name="maxplayer"></param>
/// <param name="srcCoord"></param>
/// <param name="destCoord"></param>
/// <param name="updateBoard"></param>
/// <param name="captures"></param>
/// <returns></returns>
public int AlphaBeta(Board board, int depth, int alpha, int beta, Player player, bool maxplayer,
ref Coordinate srcCoord, ref Coordinate destCoord, ref Board updateBoard,
ref IList<Coordinate> captures)
{
var robj = new Rules();
if (depth == 0 || rule.IsBoardLeaf(player, board)) // is node a terminal node
{
var obj = new HeuristicFunction();
return obj.Evaluate(board, player); //return Heurisitic value of node
}
//Finds if there are any captures
IDictionary<IList<Coordinate>, IList<Coordinate>> capturesAvailable = robj.FindCaptures(board, player);
IDictionary<Board, IList<Coordinate>> boardCoordsList;
//Calculating board according to current state (with or without captures)
if (capturesAvailable.Count > 0)
{
boardCoordsList = robj.CreateNewBoards(board, capturesAvailable);
}
else
{
boardCoordsList = robj.CalculateNewBoardsFromCoordinates(board, player);
}
//values which save capture list , source, detination on the chosen move
var minsrcCoord = new Coordinate();
var mindestCoord = new Coordinate();
var maxsrcCoord = new Coordinate();
var maxdestCoord = new Coordinate();
var maxCapturesList = new List<Coordinate>();
var minCapturesList = new List<Coordinate>();
var minBoard = new Board();
var maxBoard = new Board();
//player
if (maxplayer)
{
foreach (var newState in boardCoordsList)
{
Coordinate newSrcCoord = newState.Value[0];
Coordinate newDestCoord = newState.Value[1];
IList<Coordinate> capturesList = robj.MapContainsCoords(capturesAvailable, newSrcCoord, newDestCoord);
IList<Coordinate> tempCapList = new List<Coordinate>();
int res = AlphaBeta(newState.Key, depth - 1, alpha, beta, board.GetOpponent(player), !maxplayer,
ref newSrcCoord, ref newDestCoord, ref updateBoard, ref tempCapList);
if (res > alpha)
{
alpha = res;
maxsrcCoord = newState.Value[0];
maxdestCoord = newState.Value[1];
maxBoard = newState.Key.Copy();
maxCapturesList = new List<Coordinate>(capturesList);
}
if (beta <= alpha)
{
break;
}
if (capturesList.Count > 0)
{
capturesAvailable.Remove(capturesList);
}
}
srcCoord = maxsrcCoord;
destCoord = maxdestCoord;
updateBoard = maxBoard.Copy();
captures = maxCapturesList;
return alpha;
}
//opponent
else
{
foreach (var newState in boardCoordsList)
{
Coordinate newSrcCoord = newState.Value[0];
Coordinate newDestCoord = newState.Value[1];
IList<Coordinate> capturesList = robj.MapContainsCoords(capturesAvailable, newSrcCoord, newDestCoord);
IList<Coordinate> tempCapList = new List<Coordinate>();
int res = AlphaBeta(newState.Key, depth - 1, alpha, beta, board.GetOpponent(player), !maxplayer,
ref newSrcCoord, ref newDestCoord, ref updateBoard, ref tempCapList);
if (res < beta)
{
beta = res;
minsrcCoord = newState.Value[0];
mindestCoord = newState.Value[1];
minBoard = newState.Key.Copy();
minCapturesList = new List<Coordinate>(capturesList);
}
if (beta <= alpha)
{
break;
}
if (capturesList.Count > 0)
{
capturesAvailable.Remove(capturesList);
}
}
srcCoord = minsrcCoord;
destCoord = mindestCoord;
updateBoard = minBoard.Copy();
captures = minCapturesList;
return beta;
}
}
