private Move Minimax(BotState state, char player, int level)
{
// Terminal states:
//player has won: 10
//other player has won: -10
//tie = 0, etc...
UltimateBoard.GameStatus gameState = state.UltimateBoard.GetGameStatus();
if (gameState == UltimateBoard.GameStatus.OWon)
{
return(new Move {
Score = -100
});
}
else if (gameState == UltimateBoard.GameStatus.XWon)
{
return(new Move {
Score = 100
});
}
else if (gameState == UltimateBoard.GameStatus.Tie)
{
return(new Move {
Score = 0
});
}
// Check level == 5 then return score
if (level == 4)
{
int score = state.UltimateBoard.GetScore();
return(new Move {
Score = score
});
}
// For eac available move
// Score each move by calling Minimax with the opposite player
// opposite player
List <Move> moves = state.UltimateBoard.AvailableMoves;
foreach (Move move in moves)
{
// Save state of board and macroboard
char[,] board = (char[, ])state.UltimateBoard.Board.Clone();
char[,] macroboard = (char[, ])state.UltimateBoard.Macroboard.Clone();
// Make the move
state.UltimateBoard.MakeMove(move, player);
//StreamWriter sw = File.AppendText(@"C:\\Users\\dgillespie\\Desktop\\output.txt");
//sw.WriteLine(level);
//Score each move by calling Minimax with the
// opposite player
if (player == UltimateBoard.PlayerX)
{
move.Score = Minimax(state, UltimateBoard.PlayerO, level + 1).Score;
}
else
{
move.Score = Minimax(state, UltimateBoard.PlayerX, level + 1).Score;
}
// Basic tree pruning.
/*if (player == UltimateBoard.PlayerX)
* {
* if(move.Score == 100)
* {
* return move;
* }
* }
* else
* {
* if(move.Score == -100)
* {
* return move;
* }
* }*/
//Revert board to original state
state.UltimateBoard.Board = board;
state.UltimateBoard.Macroboard = macroboard;
}
if (player == UltimateBoard.PlayerX)
{
return(moves.Max());
}
else
{
return(moves.Min());
}
}
public BotParser(SmartBot bot)
{
this.bot = bot;
currentState = new BotState();
}
