From eb254801185067fbed40eff016503987c9ce74ef Mon Sep 17 00:00:00 2001
From: "g.levassor--gentil" <g.levassor--gentil@LJ21516.ecam.fr>
Date: Tue, 6 May 2025 16:30:32 +0200
Subject: [PATCH] AI autoplayer

---
 src/backend/AutoPlayer.java | 81 +++++++++++++++++++++++++++++++------
 src/backend/Board.java      |  2 +-
 2 files changed, 69 insertions(+), 14 deletions(-)

diff --git a/src/backend/AutoPlayer.java b/src/backend/AutoPlayer.java
index a988a22..1d15d8e 100644
--- a/src/backend/AutoPlayer.java
+++ b/src/backend/AutoPlayer.java
@@ -1,17 +1,72 @@
 package backend;
 
+import java.util.ArrayList;
+
 public class AutoPlayer {
-	
-	
-	/**
-	 * returns the best Move to try on provided board for active player
-	 * @param board
-	 * @return
-	 */
-	public Move computeBestMove(Board board) {
-		
-		return null;
-	}
-	
-	
+
+    public Move computeBestMove(Board board) {
+        ArrayList<Move> allMoves = new ArrayList<>();
+        boolean isWhite = board.isTurnWhite();
+
+        for (Piece piece : board.getPieces()) {
+            if (piece.isWhite() != isWhite) continue;
+            ArrayList<int[]> legalMoves = getLegalMoves(board, piece);
+            for (int[] move : legalMoves) {
+                Piece target = getPieceAt(board, move[0], move[1]);
+                Move candidate = new Move(
+                        piece.getType(), piece.isWhite(),
+                        piece.getX(), piece.getY(),
+                        move[0], move[1],
+                        target
+                );
+                allMoves.add(candidate);
+            }
+        }
+
+        // Evaluate moves
+        Move bestMove = null;
+        int bestScore = Integer.MIN_VALUE;
+
+        for (Move move : allMoves) {
+            int score = evaluateMove(move);
+            if (score > bestScore) {
+                bestScore = score;
+                bestMove = move;
+            }
+        }
+
+        return bestMove;
+    }
+
+    private int evaluateMove(Move move) {
+        if (move.getCapturedPiece() != null) {
+            return pieceValue(move.getCapturedPiece().getType());
+        }
+        return 0;
+    }
+
+    private int pieceValue(PieceType type) {
+        switch (type) {
+            case Pawn: return 1;
+            case Knight: return 3;
+            case Bishop: return 3;
+            case Rook: return 5;
+            case Queen: return 9;
+            case King: return 100; // just in case
+            default: return 0;
+        }
+    }
+
+    private ArrayList<int[]> getLegalMoves(Board board, Piece piece) {
+        // Reuse board's internal method
+        // But we must simulate access: simulate selection, compute, and reset
+        return board.computeLegalMoves(piece);
+    }
+
+    private Piece getPieceAt(Board board, int x, int y) {
+        for (Piece p : board.getPieces()) {
+            if (p.getX() == x && p.getY() == y) return p;
+        }
+        return null;
+    }
 }
diff --git a/src/backend/Board.java b/src/backend/Board.java
index 8c4130b..2731596 100644
--- a/src/backend/Board.java
+++ b/src/backend/Board.java
@@ -410,7 +410,7 @@ private boolean isEnemy(int x, int y, boolean isWhite) {
     return p != null && p.isWhite() != isWhite;
 }
 
-private ArrayList<int[]> computeLegalMoves(Piece piece) {
+public ArrayList<int[]> computeLegalMoves(Piece piece) {
     ArrayList<int[]> moves = new ArrayList<>();
     int x = piece.getX();
     int y = piece.getY();