From 29aadc0925e41f19bc41e8861663b54edd268419 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20B=C3=BChler?= <stbuehler@web.de>
Date: Tue, 6 Jan 2009 17:41:49 +0100
Subject: [PATCH] added some game logic (move queen)

---
 src/toruschess.cpp | 39 ++++++++++++++++++++++++++++++++++++---
 src/toruschess.h   |  4 ++--
 2 files changed, 38 insertions(+), 5 deletions(-)

diff --git a/src/toruschess.cpp b/src/toruschess.cpp
index 4a897e4..d7b5521 100644
--- a/src/toruschess.cpp
+++ b/src/toruschess.cpp
@@ -39,17 +39,50 @@ namespace toruschess {
 		memcpy(m_places, start_field, sizeof(start_field));
 	}
 
-	QList<Move> Field::validMoves(const Pos &p) {
+	void tryDirection(QList<Move> &moves, const Field *field, int thePiece, const Pos &from, int dx, int dy) {
+		for (int d = 1; d < 8; d++) {
+			Pos to = Pos(from.x() + d*dx, from.y() + d*dy);
+			int toPlace = field->place(to);
+			if (0 == toPlace) {
+				moves.push_back(Move(field, from, to)); /* move */
+			} else if (0 > toPlace * thePiece) {
+				moves.push_back(Move(field, from, to)); /* beat */
+				for (int c = 7; c > d; c--) {
+					to = Pos(from.x() + c*dx, from.y() + c*dy);
+					toPlace = field->place(to);
+					if (0 == toPlace) {
+						moves.push_back(Move(field, from, to)); /* move */
+					} else if (0 > toPlace * thePiece) {
+						moves.push_back(Move(field, from, to)); /* beat */
+						break;
+					} else {
+						break;
+					}
+				}
+				break;
+			} else {
+				break;
+			}
+		}
+	}
+
+	QList<Move> Field::validMoves(const Pos &from) const {
 		QList<Move> moves;
-		int thePlace = place(p);
+		int thePlace = place(from);
 		Piece thePiece = (Piece) qAbs(thePlace);
 		switch (thePiece) {
+		case QUEEN:
+			tryDirection(moves, this, thePiece, from, 1, 1);
+			tryDirection(moves, this, thePiece, from, 1, -1);
+			tryDirection(moves, this, thePiece, from, 1, 0);
+			tryDirection(moves, this, thePiece, from, 0, 1);
+			break;
 		case NOPIECE:
 			break;
 		}
 		return moves;
 	}
-	bool Field::validMove(const Move &m) {
+	bool Field::validMove(const Move &m) const {
 		QList<Move> moves = validMoves(m.from());
 		return moves.contains(m);
 	}
diff --git a/src/toruschess.h b/src/toruschess.h
index 49d3e84..bff9d60 100644
--- a/src/toruschess.h
+++ b/src/toruschess.h
@@ -86,8 +86,8 @@ namespace toruschess {
 		int place(const Pos &p) const { return m_places[p.y()][p.x()]; }
 		int& place(const Pos &p) { return m_places[p.y()][p.x()]; }
 		
-		QList<Move> validMoves(const Pos &p);
-		bool validMove(const Move &m);
+		QList<Move> validMoves(const Pos &from) const;
+		bool validMove(const Move &m) const;
 		bool move(const Move &m);
 		bool undo(const Move &m);