Selection display + fixes to positions

src/chess/Board.java

@@ -23,14 +23,14 @@ public class Board {
         board[size()-4][0] = new King(this, true, size() - 4, 0);
 
         // black
-        board[0][size()-1] = new Rook(this, false,0, 0);
+        board[0][size()-1] = new Rook(this, false,0, size()-1);
-        board[size()-1][size()-1] = new Rook(this, false, size() - 1, 0);
+        board[size()-1][size()-1] = new Rook(this, false, size() - 1, size()-1);
-        board[1][size()-1] = new Knight(this, false, 1, 0);
+        board[1][size()-1] = new Knight(this, false, 1, size()-1);
-        board[size()-2][size()-1] = new Knight(this, false, size() - 2, 0);
+        board[size()-2][size()-1] = new Knight(this, false, size() - 2, size()-1);
-        board[2][size()-1] = new Bishop(this, false, 2, 0);
+        board[2][size()-1] = new Bishop(this, false, 2, size()-1);
-        board[size()-3][size()-1] = new Bishop(this, false, size() - 3, 0);
+        board[size()-3][size()-1] = new Bishop(this, false, size() - 3, size()-1);
-        board[3][size()-1] = new Queen(this, false, 3, 0);
+        board[3][size()-1] = new Queen(this, false, 3, size()-1);
-        board[size()-4][size()-1] = new King(this, false, size() - 4, 0);
+        board[size()-4][size()-1] = new King(this, false, size() - 4, size()-1);
     }
 
     public boolean movePiece(int x, int y, int newX, int newY){
@@ -64,9 +64,9 @@ public class Board {
     }
 
     public ChessPiece get(int x, int y){
-        if (x < 0 || x > board.length)
+        if (x < 0 || x >= board.length)
             return null;
-        if (y < 0 || y > board.length)
+        if (y < 0 || y >= board.length)
             return null;
         return board[x][y];
     }
@@ -76,9 +76,9 @@ public class Board {
     }
 
     protected boolean set(int x, int y, ChessPiece piece){
-        if (x < 0 || x > board.length)
+        if (x < 0 || x >= board.length)
             return false;
-        if (y < 0 || y > board.length)
+        if (y < 0 || y >= board.length)
             return false;
         board[x][y] = piece;
         return true;

src/chess/ChessPiece.java

@@ -39,19 +39,19 @@ public abstract class ChessPiece {
 
     protected ArrayList<Move> getCardinalMoves(int length){
         ArrayList<Move> moves = new ArrayList<Move>();
-        for (int i = 0; i < length; i++){
+        for (int i = 1; i <= length; i++){
             // cardinals
-            moves.add(new Move(x - i, 0));
+            moves.add(new Move(x - i, y));
-            moves.add(new Move(x + i, 0));
+            moves.add(new Move(x + i, y));
-            moves.add(new Move(0, y - i));
+            moves.add(new Move(x, y - i));
-            moves.add(new Move(0, y + i));
+            moves.add(new Move(x, y + i));
         }
         return moves;
     }
 
     protected ArrayList<Move> getDiagonalMoves(int length){
         ArrayList<Move> moves = new ArrayList<Move>();
-        for (int i = 0; i < length; i++){
+        for (int i = 1; i <= length; i++){
             // cardinals
             moves.add(new Move(x - i, y - i));
             moves.add(new Move(x + i, y + i));

src/chess/King.java

@@ -7,8 +7,8 @@ import static ui.Display.loadImage;
 
 public class King extends ChessPiece {
 
-    private Image whiteKing = loadImage("./resources/chess_piece_2_black_king.png");
+    private final Image whiteKing = loadImage("./resources/chess_piece_2_black_king.png");
-    private Image blackKing = loadImage("./resources/chess_piece_2_white_king.png");
+    private final Image blackKing = loadImage("./resources/chess_piece_2_white_king.png");
 
     public King(Board b, boolean isWhite, int x, int y) {
         super(b,isWhite,x,y);

src/chess/Pawn.java

@@ -23,31 +23,41 @@ public class Pawn extends ChessPiece {
     @Override
     public ArrayList<Move> getMoves() {
         ArrayList<Move> moves = new ArrayList<Move>();
+        if (isWhite) {
             moves.add(new Move(x, y + 1));
             if (isFirstMove)
                 moves.add(new Move(x, y + 2));
+        } else {
+            moves.add(new Move(x, y - 1));
+            if (isFirstMove)
+                moves.add(new Move(x, y - 2));
+        }
         ChessPiece neighbour = null;
 
         if (isWhite){
             // En passant
-            if ((neighbour = b.get(x-1, y)) != null && neighbour instanceof Pawn && ((Pawn) neighbour).isFirstMove())
+            if ((neighbour = b.get(x-1, y)) != null && checkNeighbourEnPassant(neighbour))
                 moves.add(new Move(x-1, y + 1, Move.SpecialConditions.leftEnPassant));
             // En passant
-            if ((neighbour = b.get(x+1, y)) != null && neighbour instanceof Pawn && ((Pawn) neighbour).isFirstMove())
+            if ((neighbour = b.get(x+1, y)) != null && checkNeighbourEnPassant(neighbour))
                 moves.add(new Move(x+1, + 1, Move.SpecialConditions.rightEnPassant));
         } else {
             // unfortunately have to flip the direction depending on player type
             // En passant
-            if ((neighbour = b.get(x-1, y)) != null && neighbour instanceof Pawn && ((Pawn) neighbour).isFirstMove())
+            if ((neighbour = b.get(x-1, y)) != null && checkNeighbourEnPassant(neighbour))
                 moves.add(new Move(x-1, y - 1, Move.SpecialConditions.leftEnPassant));
             // En passant
-            if ((neighbour = b.get(x+1, y)) != null && neighbour instanceof Pawn && ((Pawn) neighbour).isFirstMove())
+            if ((neighbour = b.get(x+1, y)) != null && checkNeighbourEnPassant(neighbour))
                 moves.add(new Move(x+1, - 1, Move.SpecialConditions.rightEnPassant));
         }
 
         return moves;
     }
 
+    private boolean checkNeighbourEnPassant(ChessPiece neighbour){
+        return neighbour instanceof Pawn && ((Pawn) neighbour).isFirstMove() && neighbour.isWhite != this.isWhite;
+    }
+
     @Override
     public void applySpecialMove(Move moveWithSpecial){
         var specialCondition = moveWithSpecial.getSpecialCondition();

src/ui/Display.java

@@ -1,16 +1,24 @@
 package ui;
 
 import chess.Board;
+import chess.Move;
 
 import javax.imageio.ImageIO;
 import javax.swing.*;
 import javax.swing.text.AttributeSet;
 import java.awt.*;
+import java.awt.event.MouseEvent;
+import java.awt.event.MouseListener;
 import java.io.File;
 import java.io.IOException;
 import java.text.AttributedString;
 
-public class Display extends JFrame {
+public class Display extends JFrame implements MouseListener {
+
+    private static int xOffset = 128, yOffset = 128;
+    private static int width = 64, height = 64;
+    private int movingPointX = -1, movingPointY = -1;
+    private int selectionPointX = -1, selectionPointY = -1;
 
     private Board b;
 
@@ -21,6 +29,7 @@ public class Display extends JFrame {
         this.setVisible(true);
         this.setEnabled(true);
         this.setTitle("Ratatta");
+        this.addMouseListener(this);
     }
 
     @Override
@@ -29,9 +38,35 @@ public class Display extends JFrame {
         for (int i = 0; i < b.size(); i++){
             for (int j = 0; j < b.size(); j++){
                 if (b.get(i,j) != null)
-                    g.drawImage(b.get(i,j).getImage(), (i+2) * 64, (j+2) * 64, null);
+                    g.drawImage(b.get(i,j).getImage(), xOffset + (i) * width, yOffset + (j) * height, null);
             }
         }
+        if (movingPointX != -1 && movingPointY != -1) {
+            var piece = b.get(movingPointX, movingPointY);
+            if (piece != null) {
+                var moves = piece.getMoves();
+                for (Move m : moves) {
+                    drawSelectionRect(g, m);
+                }
+            }
+        }
+        // handle user input (mouse clicking)
+        if (selectionPointX != -1 && selectionPointY != -1){
+            int localPointX = (selectionPointX - xOffset) / width;
+            int localPointY = (b.size()-1) - ((selectionPointY - yOffset) / height);
+            var piece = b.get(localPointX, localPointY);
+            if (piece != null) {
+                movingPointX = localPointX;
+                movingPointY = localPointY;
+            }
+            System.out.println(localPointX + " " + localPointY);
+            selectionPointY = -1;
+            selectionPointX = -1;
+        }
+    }
+
+    private void drawSelectionRect(Graphics g, Move m){
+        g.drawRect(xOffset + (m.getX() * width), yOffset + ((b.size()-1 - m.getY()) * height), width, height);
     }
 
     public boolean update(){
@@ -45,4 +80,30 @@ public class Display extends JFrame {
             throw new RuntimeException(e);
         }
     }
+
+    @Override
+    public void mouseClicked(MouseEvent mouseEvent) {
+        this.selectionPointX = mouseEvent.getX();
+        this.selectionPointY = mouseEvent.getY();
+    }
+
+    @Override
+    public void mousePressed(MouseEvent mouseEvent) {
+
+    }
+
+    @Override
+    public void mouseReleased(MouseEvent mouseEvent) {
+
+    }
+
+    @Override
+    public void mouseEntered(MouseEvent mouseEvent) {
+
+    }
+
+    @Override
+    public void mouseExited(MouseEvent mouseEvent) {
+
+    }
 }