From ae9edbb08d8940001c03386e6501bce8c5cabb96 Mon Sep 17 00:00:00 2001
From: ehouse <ehouse@0782aaa5-4710-0410-8820-a96bf9123855>
Date: Sun, 29 Feb 2004 06:59:37 +0000
Subject: [PATCH] After an undo, set the prev_move bits on the move now on top
 of the stack so the tiles will get highlighted.

---
 xwords4/common/model.c | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/xwords4/common/model.c b/xwords4/common/model.c
index 629135ba4..becd8a64c 100644
--- a/xwords4/common/model.c
+++ b/xwords4/common/model.c
@@ -581,6 +581,41 @@ model_undoLatestMoves( ModelCtxt* model, PoolContext* pool,
         }
     }
 
+    /* If there's still a move on top of the stack, highlight its tiles since
+       they're now the most recent move. */
+    for ( ; ; ) {
+        StackEntry entry;
+        XP_U16 movesLeft = stack_getNEntries( stack );
+        if ( movesLeft == 0 ||
+             !stack_getNthEntry( stack, movesLeft - 1, &entry ) ) {
+            break;
+        }
+        if ( entry.moveType == MOVE_TYPE ) {
+            XP_U16 nTiles = entry.u.move.moveInfo.nTiles;
+            XP_U16 col, row;
+            XP_U16* varies;
+
+            if ( entry.u.move.moveInfo.isHorizontal ) {
+                row = entry.u.move.moveInfo.commonCoord;
+                varies = &col;
+            } else {
+                col = entry.u.move.moveInfo.commonCoord;
+                varies = &row;
+            }
+
+            while ( nTiles-- ) {
+                CellTile tile;
+
+                *varies = entry.u.move.moveInfo.tiles[nTiles].varCoord;
+                tile = getModelTileRaw( model, col, row );
+                setModelTileRaw( model, col, row, (CellTile)(tile | PREV_MOVE_BIT) );
+
+                notifyBoardListeners( model, entry.playerNum, col, row, XP_FALSE );
+            }
+            break;
+        }
+    }
+
     if ( nMovesUndone != nMovesSought ) {
         success = XP_FALSE;
     }