From 9f5b27769fae5469c316297b786e11dc9a26127d Mon Sep 17 00:00:00 2001
From: Guillaume VALLENET <guillaume.vallenet@ecam.fr>
Date: Fri, 25 Apr 2025 15:40:41 +0200
Subject: [PATCH] Actualiser src/backend/AutoPlayer.java

---
 src/backend/AutoPlayer.java | 163 +++++++++++++++++++++++++++++++++++-
 1 file changed, 159 insertions(+), 4 deletions(-)

diff --git a/src/backend/AutoPlayer.java b/src/backend/AutoPlayer.java
index 3e67f52..9b753af 100644
--- a/src/backend/AutoPlayer.java
+++ b/src/backend/AutoPlayer.java
@@ -1,10 +1,165 @@
 package backend;
 
+import java.util.ArrayList;
+import java.util.Random;
+
 public class AutoPlayer {
+    private static final int MAX_DEPTH = 2; // Reduced depth for faster computation
+    private static final Random random = new Random();
     
+    /**
+     * Computes a move for the current player with a deliberate delay
+     * 
+     * @param board Current state of the board
+     * @return A reasonable move
+     */
     public Move computeBestMove(Board board) {
-        // This will be implemented in Part 4
-        // For now, just return null or a placeholder move
-        return null;
+        if (board == null) {
+            return null;
+        }
+        
+        // Add deliberate delay to simulate "thinking"
+        try {
+            Thread.sleep(500); // 0.5 second delay
+        } catch (InterruptedException e) {
+            // Ignore interruption
+        }
+        
+        boolean isWhiteTurn = board.isTurnWhite();
+        ArrayList<Move> possibleMoves = generatePossibleMoves(board);
+        
+        if (possibleMoves.isEmpty()) {
+            return null;
+        }
+        
+        // 20% chance to make a random move for unpredictability
+        if (random.nextDouble() < 0.2) {
+            return possibleMoves.get(random.nextInt(possibleMoves.size()));
+        }
+        
+        Move bestMove = null;
+        int bestScore = isWhiteTurn ? Integer.MIN_VALUE : Integer.MAX_VALUE;
+        
+        for (Move move : possibleMoves) {
+            Board boardCopy = new Board(board);
+            boardCopy.playMove(move);
+            
+            int score = minimax(boardCopy, MAX_DEPTH - 1, !isWhiteTurn);
+            
+            if ((isWhiteTurn && score > bestScore) || (!isWhiteTurn && score < bestScore)) {
+                bestScore = score;
+                bestMove = move;
+            }
+        }
+        
+        return bestMove != null ? bestMove : possibleMoves.get(random.nextInt(possibleMoves.size()));
     }
-}
\ No newline at end of file
+    
+    /**
+     * Simplified minimax algorithm without alpha-beta pruning
+     */
+    private int minimax(Board board, int depth, boolean isWhiteTurn) {
+        if (depth == 0) {
+            return evaluateBoard(board);
+        }
+        
+        ArrayList<Move> possibleMoves = generatePossibleMoves(board);
+        
+        if (possibleMoves.isEmpty()) {
+            return evaluateBoard(board);
+        }
+        
+        int bestScore = isWhiteTurn ? Integer.MIN_VALUE : Integer.MAX_VALUE;
+        
+        for (Move move : possibleMoves) {
+            Board boardCopy = new Board(board);
+            boardCopy.playMove(move);
+            
+            int score = minimax(boardCopy, depth - 1, !isWhiteTurn);
+            
+            if (isWhiteTurn) {
+                bestScore = Math.max(bestScore, score);
+            } else {
+                bestScore = Math.min(bestScore, score);
+            }
+        }
+        
+        return bestScore;
+    }
+    
+    /**
+     * Simplified board evaluation
+     */
+    private int evaluateBoard(Board board) {
+        int score = 0;
+        
+        for (Piece piece : board.getPieces()) {
+            int pieceValue = getPieceValue(piece.getType());
+            score += piece.isWhite() ? pieceValue : -pieceValue;
+        }
+        
+        return score;
+    }
+    
+    /**
+     * Basic piece values
+     */
+    private int getPieceValue(PieceType type) {
+        switch (type) {
+            case Pawn: return 100;
+            case Knight: return 300;
+            case Bishop: return 300;
+            case Rook: return 500;
+            case Queen: return 900;
+            case King: return 10000;
+            default: return 0;
+        }
+    }
+    
+    /**
+     * Generates all possible legal moves for the current player
+     */
+    private ArrayList<Move> generatePossibleMoves(Board board) {
+        ArrayList<Move> possibleMoves = new ArrayList<>();
+        boolean isWhiteTurn = board.isTurnWhite();
+        
+        for (Piece piece : board.getPieces()) {
+            if (piece.isWhite() == isWhiteTurn) {
+                possibleMoves.addAll(generateMovesForPiece(board, piece));
+            }
+        }
+        
+        return possibleMoves;
+    }
+    
+    /**
+     * Generates all possible legal moves for a specific piece
+     */
+    private ArrayList<Move> generateMovesForPiece(Board board, Piece piece) {
+        ArrayList<Move> moves = new ArrayList<>();
+        int x = piece.getX();
+        int y = piece.getY();
+        
+        Board tempBoard = new Board(board);
+        tempBoard.userTouch(x, y);
+        
+        for (int toX = 0; toX < board.getWidth(); toX++) {
+            for (int toY = 0; toY < board.getHeight(); toY++) {
+                if (tempBoard.isHighlighted(toX, toY)) {
+                    Piece capturedPiece = null;
+                    
+                    for (Piece boardPiece : board.getPieces()) {
+                        if (boardPiece.getX() == toX && boardPiece.getY() == toY) {
+                            capturedPiece = boardPiece;
+                            break;
+                        }
+                    }
+                    
+                    moves.add(new Move(x, y, toX, toY, piece, capturedPiece));
+                }
+            }
+        }
+        
+        return moves;
+    }
+}