Updated on autoplayer

src/backend/AutoPlayer.java

@@ -1,6 +1,8 @@
 package backend;
+
 import java.util.ArrayList;
 import java.util.Random;
+
 public class AutoPlayer {
 	private Random rand = new Random();
 	
@@ -12,26 +14,74 @@ public class AutoPlayer {
 	 */
 	public Move computeBestMove(Board board) {
 		ArrayList<Move> allMoves = new ArrayList<>();
+		Move bestMove = null;
+		int bestScore = Integer.MIN_VALUE;
+		
+		//Detect Ai's color
+		boolean aiIsWhite = board.isTurnWhite();
+		
 		//Go through all pieces on the board
 		for(Piece piece : board.getPieces()) {
 			//only choose the active color's piece
 			if(piece.isWhite() == board.isTurnWhite()) {
 				//Get valid moves for this piece
 				ArrayList<int[]> validMoves = board.getValidMoves(piece);
+				
 				//convert each position into a move object
 				for (int[] dest : validMoves) {
+					Board simulatedBoard = new Board(board);//copy the board first
+					Piece simpiece = simulatedBoard.board[piece.getY()][piece.getX()]; //get matching piece in the copied board
 					Move move = new Move(piece, dest[0], dest[1]);
-					allMoves.add(move);
+					simulatedBoard.playMove(move);
+					
+					int score = evaluate(simulatedBoard, aiIsWhite);
+					
+					if (score > bestScore) {
+						bestScore = score;
+						bestMove = new Move(piece, dest[0], dest[1]);//use original piece for
+					}
 				}
 			}
 		}
-		//Pick a random move from the list
+		return bestMove;
-		if (!allMoves.isEmpty()) {
-			return allMoves.get(rand.nextInt(allMoves.size()));
-			
-		}
-		return null;
 	}
+		//Helper method to score a board state
+	private int evaluate(Board board, boolean aiIsWhite) {
+			int score = 0;
 			
+			for (Piece p : board.getPieces()) {
+				int value = 0;
 				
+				switch (p.getType()) {
+				case Pawn:
+					value = 1;
+					break;
+				case Knight:
+				case Bishop: 
+					value = 3;
+					break;
+				case Rook:
+					value = 5;
+					break;
+				case Queen:
+				    value = 9;
+				    break; 
+				case King:
+					value = 1000;
+					break;
+				}
+			
+		//Add value if iit's current turnn's color, subtract if opponent
+		     if (p.isWhite() == aiIsWhite) {
+			     score += value;
+		     }
+		     else {
+			     score -= value;
+		     }
+	}
+		return score;
 }
+}
+	
+	
+