public static int evaluate(Game game, char player) {
if (game.isGameOver()) {
for (int i = 0; i < Board.ROWS; i++) {
for (int j = 0; j < Board.COLUMNS; j++) {
if (game.getBoard().matrix[i][j] != Board.EMPTY) {
int piece = game.getBoard().matrix[i][j];
if (piece == Board.BLACK_SOLDIER || piece == Board.BLACK_KING) {
if (player == Move.BLACK) {
return 100;
} else {
return -100;
}
} else if (piece == Board.RED_SOLDIER || piece == Board.RED_KING) {
if (player == Move.RED) {
return 100;
} else {
return -100;
}
}
}
}
}
} else {
int numBlackKings = 0, numRedKings = 0;
int numBlackPieces = 0, numRedPieces = 0;
for (int i = 0; i < Board.ROWS; i++) {
for (int j = 0; j < Board.COLUMNS; j++) {
int piece = game.getBoard().matrix[i][j];
if (piece != Board.EMPTY) {
if (piece == Board.BLACK_KING) {
numBlackKings++;
numBlackPieces++;
} else if (piece == Board.RED_KING) {
numRedKings++;
numRedPieces++;
} else if (piece == Board.BLACK_SOLDIER) {
numBlackPieces++;
} else if (piece == Board.RED_SOLDIER) {
numRedPieces++;
}
}
}
}
int score = 0;
score += 6 * (numBlackPieces - numRedPieces);
score += (28f / 12f) * (numBlackKings - numRedKings);
if (player == Move.RED) {
score *= -1;
}
return score;
}
return 0;
}
public static int MiniMax(Game game, char player, int depth, int maxDepth) {
if (depth == maxDepth || game.isGameOver()) {
return evaluate(game, player);
}
Move bestMove = null;
int bestScore;
if (game.getTurn() == player) {
bestScore = Integer.MIN_VALUE;
} else {
bestScore = Integer.MAX_VALUE;
}
List<Move> allMoves = getMoves(game, game.getTurn());
for (Move move : allMoves) {
int[][] matrixCopy = game.getBoard().getMatrixCopy();
game.processMove(move.getCopy());
game.changeTurn();
int moveScore = MiniMax(game, player, depth + 1, maxDepth);
game.changeTurn();
game.getBoard().setMatrix(matrixCopy);
if (game.getTurn() == player) {
if (moveScore > bestScore) {
bestScore = moveScore;
bestMove = move.getCopy();
}
} else {
if (moveScore < bestScore) {
bestScore = moveScore;
bestMove = move.getCopy();
}
}
}
if (depth == 0) {
computedBestMove = bestMove;
}
return bestScore;
}