# HG changeset patch
# User Jens Alfke <jens@mooseyard.com>
# Date 1216412819 25200
# Node ID 7c9ecb09a61288b84c72dd9f430d9e7e382d8f30
# Parent  3b750982ff3966f26c8be73048e41c330e3be49e
Checkers and Hexchequer now detect victory when the other player can't move.

diff -r 3b750982ff39 -r 7c9ecb09a612 Source/CheckersGame.h
--- a/Source/CheckersGame.h	Thu Jul 17 13:29:04 2008 -0700
+++ b/Source/CheckersGame.h	Fri Jul 18 13:26:59 2008 -0700
@@ -21,7 +21,7 @@
     THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 #import "Game+Protected.h"
-@class Grid;
+@class Grid, GridCell;
 
 
 /** US Checkers, known as Draughts in the UK. (Other countries use similar but not identical rules.)
@@ -31,4 +31,7 @@
     Grid *_board;
 }
 
+//protected
+- (BOOL) canOpponentMoveFrom: (GridCell*)src;
+
 @end
diff -r 3b750982ff39 -r 7c9ecb09a612 Source/CheckersGame.m
--- a/Source/CheckersGame.m	Thu Jul 17 13:29:04 2008 -0700
+++ b/Source/CheckersGame.m	Fri Jul 18 13:26:59 2008 -0700
@@ -176,13 +176,32 @@
     [self endTurn];
 }
 
+#pragma mark -
+#pragma mark CHECK FOR WIN:
+
+static BOOL canOpponentMoveOrJump( GridCell *first, GridCell *second ) {
+    return first.empty || (first.bit.friendly && second.empty);
+}
+
+- (BOOL) canOpponentMoveFrom: (GridCell*)src
+{
+    if( ! src.bit.unfriendly )
+        return NO;
+    Square *square = (Square*)src;
+    if( square.bit.tag )           // remember, it's opponent's piece, so directions are reversed
+        if( canOpponentMoveOrJump(square.fl,square.fl.fl) || canOpponentMoveOrJump(square.fr,square.fr.fr) )
+            return YES;
+    return canOpponentMoveOrJump(square.bl,square.bl.bl) || canOpponentMoveOrJump(square.br,square.br.br);
+}
+
 - (Player*) checkForWinner
 {
-    NSCountedSet *remaining = _board.countPiecesByPlayer;
-    if( remaining.count==1 )
-        return [remaining anyObject];
-    else
-        return nil;
+    for( GridCell *cell in _board.cells )
+        if( [self canOpponentMoveFrom: cell] ) {
+            Log(@"Checkers: %@ can move from %@",self.currentPlayer.nextPlayer,cell);
+            return nil;
+        }
+    return self.currentPlayer;
 }
 
 
diff -r 3b750982ff39 -r 7c9ecb09a612 Source/HexchequerGame.m
--- a/Source/HexchequerGame.m	Thu Jul 17 13:29:04 2008 -0700
+++ b/Source/HexchequerGame.m	Fri Jul 18 13:26:59 2008 -0700
@@ -127,5 +127,17 @@
     [self endTurn];
 }
 
+- (BOOL) canOpponentMoveFrom: (GridCell*)src
+{
+    if( ! src.bit.unfriendly )
+        return NO;
+    if( [super canOpponentMoveFrom: src] )
+        return YES;
+    Hex *hex = (Hex*)src;
+    if( hex.bit.tag )           // remember, it's opponent's piece, so directions are reversed
+        if( hex.r.empty || (hex.r.bit.friendly && hex.r.r.empty) )
+            return YES;
+    return hex.l.empty || (hex.l.bit.friendly && hex.l.l.empty);
+}
 
 @end