Merge pull request #320 from metanorma/fix/vertical_layout_footnotes

Fix/vertical layout footnotes

src/main/java/org/apache/fop/layoutmgr/FootnoteBodyLayoutManager.java

@@ -0,0 +1,134 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* $Id$ */
+
+package org.apache.fop.layoutmgr;
+
+import java.util.LinkedList;
+import java.util.List;
+
+import org.apache.fop.area.Area;
+import org.apache.fop.fo.flow.FootnoteBody;
+import org.apache.fop.fo.pagination.Region;
+import org.apache.fop.traits.WritingMode;
+
+/**
+ * Layout manager for footnote bodies.
+ */
+public class FootnoteBodyLayoutManager extends BlockStackingLayoutManager {
+
+    private List<ListElement> knuthElements;
+
+    /**
+     * Creates a new FootnoteBodyLayoutManager.
+     * @param body the footnote-body element
+     */
+    public FootnoteBodyLayoutManager(FootnoteBody body) {
+        super(body);
+    }
+
+    @Override
+    public List getNextKnuthElements(LayoutContext context, int alignment) {
+        if (knuthElements == null) {
+            // added for fixing https://github.com/metanorma/xmlgraphics-fop/issues/37
+            context.setWritingMode(getCurrentPage().getSimplePageMaster().getRegion(Region.FO_REGION_BODY).getWritingMode());
+            knuthElements = super.getNextKnuthElements(context, alignment);
+        }
+        return knuthElements;
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public void addAreas(PositionIterator parentIter, LayoutContext layoutContext) {
+        LayoutManager childLM;
+        LayoutManager lastLM = null;
+        LayoutContext lc = LayoutContext.newInstance();
+
+        // "unwrap" the NonLeafPositions stored in parentIter
+        // and put them in a new list;
+        LinkedList<Position> positionList = new LinkedList<Position>();
+        Position pos;
+        while (parentIter.hasNext()) {
+            pos = parentIter.next();
+            Position innerPosition;
+            if (pos instanceof NonLeafPosition) {
+                innerPosition = pos.getPosition();
+                if (innerPosition.getLM() == this) {
+                    // pos was created by this LM and was inside a penalty
+                    // allowing or forbidding a page break
+                    // nothing to do
+                } else {
+                    // innerPosition was created by another LM
+                    positionList.add(innerPosition);
+                    lastLM = innerPosition.getLM();
+                }
+            }
+        }
+
+        // the Positions in positionList were inside the elements
+        // created by the LineLM
+        PositionIterator childPosIter = new PositionIterator(positionList.listIterator());
+
+        while ((childLM = childPosIter.getNextChildLM()) != null) {
+            // set last area flag
+            lc.setFlags(LayoutContext.LAST_AREA,
+                    (layoutContext.isLastArea() && childLM == lastLM));
+            // Add the line areas to Area
+            childLM.setFromFootnote(true);
+            childLM.addAreas(childPosIter, lc);
+        }
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public void addChildArea(Area childArea) {
+        childArea.setAreaClass(Area.CLASS_FOOTNOTE);
+        childArea.setFromFootnote(true);
+        parentLayoutManager.addChildArea(childArea);
+    }
+
+    /** @return the FootnoteBody node */
+    protected FootnoteBody getFootnodeBodyFO() {
+        return (FootnoteBody) fobj;
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public Keep getKeepTogether() {
+        return getParentKeepTogether();
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public Keep getKeepWithNext() {
+        return Keep.KEEP_AUTO;
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public Keep getKeepWithPrevious() {
+        return Keep.KEEP_AUTO;
+    }
+
+    @Override
+    public void reset() {
+        super.reset();
+        knuthElements = null;
+    }
+
+}