Fix saving games from history. (#10497)

Fix saving games from history. This got broken by my recent history changes.

Also a few clean ups.

Author: asvitkine

game-app/game-core/src/main/java/games/strategy/engine/history/History.java

@@ -9,6 +9,7 @@
 import java.util.ArrayList;
 import java.util.Enumeration;
 import java.util.List;
+import java.util.Optional;
 import javax.swing.tree.DefaultMutableTreeNode;
 import javax.swing.tree.DefaultTreeModel;
 
@@ -131,12 +132,15 @@ public synchronized void gotoNode(final HistoryNode node) {
    * removes all changes that occurred after this node.
    */
   public synchronized void removeAllHistoryAfterNode(final HistoryNode removeAfterNode) {
-    gotoNode(removeAfterNode);
     assertCorrectThread();
+    if (!seekingEnabled) {
+      nextChangeIndex = changes.size();
+      seekingEnabled = true;
+    }
+    gotoNode(getNearestLeafAtOrBefore(removeAfterNode).orElse((HistoryNode) getRoot()));
     try (GameData.Unlocker ignored = gameData.acquireWriteLock()) {
-      final int lastChange = getLastChange(removeAfterNode) + 1;
-      while (changes.size() > lastChange) {
-        changes.remove(lastChange);
+      if (changes.size() > nextChangeIndex) {
+        changes.subList(nextChangeIndex, changes.size()).clear();
       }
       final Enumeration<?> enumeration =
           ((DefaultMutableTreeNode) this.getRoot()).preorderEnumeration();
@@ -147,20 +151,27 @@ public synchronized void removeAllHistoryAfterNode(final HistoryNode removeAfter
         final HistoryNode node = (HistoryNode) enumeration.nextElement();
         if (node instanceof IndexedHistoryNode) {
           final int index = ((IndexedHistoryNode) node).getChangeStartIndex();
-          if (index >= lastChange) {
+          if (index >= nextChangeIndex) {
             startRemoving = true;
           }
           if (startRemoving) {
             nodesToRemove.add(node);
           }
         }
       }
-      while (!nodesToRemove.isEmpty()) {
-        removeNodeFromParent(nodesToRemove.remove(0));
+      for (HistoryNode node : nodesToRemove) {
+        removeNodeFromParent(node);
       }
     }
   }
 
+  public Optional<HistoryNode> getNearestLeafAtOrBefore(HistoryNode node) {
+    if (node.isLeaf()) {
+      return Optional.of(node);
+    }
+    return Optional.ofNullable((HistoryNode) node.getPreviousLeaf());
+  }
+
   synchronized void changeAdded(final Change change) {
     changes.add(change);
     if (seekingEnabled && nextChangeIndex == changes.size()) {

game-app/game-core/src/main/java/games/strategy/triplea/ui/TripleAFrame.java

@@ -1881,7 +1881,6 @@ public void actionPerformed(final ActionEvent ae) {
                                     Injections.getInstance().getEngineVersion())
                                 .orElse(null);
                         if (datacopy != null) {
-                          datacopy.getHistory().gotoNode(historyPanel.getCurrentPopupNode());
                           datacopy
                               .getHistory()
                               .removeAllHistoryAfterNode(historyPanel.getCurrentPopupNode());
@@ -1901,14 +1900,11 @@ public void actionPerformed(final ActionEvent ae) {
                               datacopy.getSequence().getStep(0).getDisplayName();
                           GamePlayer currentPlayer =
                               datacopy.getSequence().getStep(0).getPlayerId();
+                          int roundOffset = datacopy.getSequence().getRoundOffset();
                           while (enumeration.hasMoreElements()) {
                             final HistoryNode node = (HistoryNode) enumeration.nextElement();
                             if (node instanceof Round) {
-                              round =
-                                  Math.max(
-                                      0,
-                                      ((Round) node).getRoundNo()
-                                          - datacopy.getSequence().getRoundOffset());
+                              round = Math.max(0, ((Round) node).getRoundNo() - roundOffset);
                               currentPlayer = null;
                               stepDisplayName = node.getTitle();
                             } else if (node instanceof Step) {

game-app/game-core/src/main/java/games/strategy/triplea/ui/history/HistoryPanel.java

@@ -275,13 +275,8 @@ private void gotoNode(final HistoryNode node) {
     // If this is not a leaf node, set the game state to the last leaf node before it. This way,
     // selecting something like "Round 3" shows the state at the start of the round, which ensures
     // chronological order when moving up/down the nodes using arrow keys even if some are expanded.
-    if (!node.isLeaf()) {
-      final TreeNode leaf = node.getPreviousLeaf();
-      // If no previous leaf, select the root node.
-      data.getHistory().gotoNode((HistoryNode) Optional.ofNullable(leaf).orElse(node.getRoot()));
-    } else {
-      data.getHistory().gotoNode(node);
-    }
+    Optional<HistoryNode> target = data.getHistory().getNearestLeafAtOrBefore(node);
+    data.getHistory().gotoNode(target.orElse((HistoryNode) node.getRoot()));
   }
 
   public HistoryNode getCurrentNode() {