/*
* 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: BlockLayoutManager.java 1334058 2012-05-04 16:52:35Z gadams $ */
package org.apache.fop.layoutmgr;
import java.util.LinkedList;
import java.util.List;
import java.util.ListIterator;
import java.util.Stack;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.fop.area.Area;
import org.apache.fop.area.Block;
import org.apache.fop.area.LineArea;
import org.apache.fop.datatypes.Length;
import org.apache.fop.fo.properties.KeepProperty;
import org.apache.fop.fonts.Font;
import org.apache.fop.fonts.FontInfo;
import org.apache.fop.fonts.FontTriplet;
import org.apache.fop.layoutmgr.inline.InlineLevelLayoutManager;
import org.apache.fop.layoutmgr.inline.LineLayoutManager;
import org.apache.fop.traits.MinOptMax;
import org.apache.fop.traits.SpaceVal;
/**
* LayoutManager for a block FO.
*/
public class BlockLayoutManager extends BlockStackingLayoutManager implements ConditionalElementListener,
BreakOpportunity {
/** logging instance */
private static Log log = LogFactory.getLog(BlockLayoutManager.class);
private Block curBlockArea;
/** Iterator over the child layout managers. */
protected ListIterator<LayoutManager> proxyLMiter;
private int lead = 12000;
private Length lineHeight;
private int follow = 2000;
//private int middleShift = 0;
private boolean discardBorderBefore;
private boolean discardBorderAfter;
private boolean discardPaddingBefore;
private boolean discardPaddingAfter;
private MinOptMax effSpaceBefore;
private MinOptMax effSpaceAfter;
/**
* Creates a new BlockLayoutManager.
* @param inBlock the block FO object to create the layout manager for.
*/
public BlockLayoutManager(org.apache.fop.fo.flow.Block inBlock) {
super(inBlock);
proxyLMiter = new ProxyLMiter();
}
/** {@inheritDoc} */
@Override
public void initialize() {
super.initialize();
org.apache.fop.fo.flow.Block fo = getBlockFO();
FontInfo fi = fo.getFOEventHandler().getFontInfo();
FontTriplet[] fontkeys = fo.getCommonFont().getFontState(fi);
Font initFont = fi.getFontInstance(fontkeys[0],
getBlockFO().getCommonFont().fontSize.getValue(this));
lead = initFont.getAscender();
follow = -initFont.getDescender();
//middleShift = -fs.getXHeight() / 2;
lineHeight = fo.getLineHeight().getOptimum(this).getLength();
startIndent = fo.getCommonMarginBlock().startIndent.getValue(this);
endIndent = fo.getCommonMarginBlock().endIndent.getValue(this);
foSpaceBefore = new SpaceVal(fo.getCommonMarginBlock().spaceBefore, this).getSpace();
foSpaceAfter = new SpaceVal(fo.getCommonMarginBlock().spaceAfter, this).getSpace();
// use optimum space values
adjustedSpaceBefore = fo.getCommonMarginBlock().spaceBefore.getSpace()
.getOptimum(this).getLength().getValue(this);
adjustedSpaceAfter = fo.getCommonMarginBlock().spaceAfter.getSpace()
.getOptimum(this).getLength().getValue(this);
}
/** {@inheritDoc} */
@Override
public List getNextKnuthElements(LayoutContext context, int alignment) {
return getNextKnuthElements(context, alignment, null, null, null);
}
/** {@inheritDoc} */
@Override
public List getNextKnuthElements(LayoutContext context, int alignment, Stack lmStack,
Position restartPosition, LayoutManager restartAtLM) {
resetSpaces();
return super.getNextKnuthElements(
context, alignment, lmStack, restartPosition, restartAtLM);
}
/**
* Overridden to take into account that the childLM may be the block's
* {@link LineLayoutManager}.
* {@inheritDoc}
*/
@Override
protected List<ListElement> getNextChildElements(LayoutManager childLM, LayoutContext context,
LayoutContext childLC, int alignment, Stack lmStack, Position restartPosition,
LayoutManager restartAtLM) {
childLC.copyPendingMarksFrom(context);
if (childLM instanceof LineLayoutManager) {
childLC.setRefIPD(getContentAreaIPD());
} else {
// nop; will have been properly set by makeChildLayoutContext()
}
if (childLM == this.childLMs.get(0)) {
childLC.setFlags(LayoutContext.SUPPRESS_BREAK_BEFORE);
//Handled already by the parent (break collapsing, see above)
}
if (lmStack == null) {
return childLM.getNextKnuthElements(childLC, alignment);
} else {
if (childLM instanceof LineLayoutManager) {
assert (restartPosition instanceof LeafPosition);
return ((LineLayoutManager) childLM).getNextKnuthElements(childLC, alignment,
(LeafPosition) restartPosition);
} else {
return childLM.getNextKnuthElements(childLC, alignment,
lmStack, restartPosition, restartAtLM);
}
}
}
private void resetSpaces() {
this.discardBorderBefore = false;
this.discardBorderAfter = false;
this.discardPaddingBefore = false;
this.discardPaddingAfter = false;
this.effSpaceBefore = null;
this.effSpaceAfter = null;
}
/**
* Proxy iterator for Block LM.
* This iterator creates and holds the complete list
* of child LMs.
* It uses fobjIter as its base iterator.
* Block LM's createNextChildLMs uses this iterator
* as its base iterator.
*/
protected class ProxyLMiter extends LMiter {
/**
* Constructs a proxy iterator for Block LM.
*/
public ProxyLMiter() {
super(BlockLayoutManager.this);
listLMs = new java.util.ArrayList<LayoutManager>(10);
}
/**
* @return true if there are more child lms
*/
public boolean hasNext() {
return (curPos < listLMs.size()) || createNextChildLMs(curPos);
}
/**
* @param pos ...
* @return true if new child lms were added
*/
protected boolean createNextChildLMs(int pos) {
List<LayoutManager> newLMs = createChildLMs(pos + 1 - listLMs.size());
if (newLMs != null) {
listLMs.addAll(newLMs);
}
return pos < listLMs.size();
}
}
/** {@inheritDoc} */
@Override
public boolean createNextChildLMs(int pos) {
while (proxyLMiter.hasNext()) {
LayoutManager lm = proxyLMiter.next();
if (lm instanceof InlineLevelLayoutManager) {
LineLayoutManager lineLM = createLineManager(lm);
addChildLM(lineLM);
} else {
addChildLM(lm);
}
if (pos < childLMs.size()) {
return true;
}
}
return false;
}
/**
* Create a new LineLM, and collect all consecutive
* inline generating LMs as its child LMs.
* @param firstlm First LM in new LineLM
* @return the newly created LineLM
*/
private LineLayoutManager createLineManager(LayoutManager firstlm) {
LineLayoutManager llm;
llm = new LineLayoutManager(getBlockFO(), lineHeight, lead, follow);
List<LayoutManager> inlines = new java.util.ArrayList<LayoutManager>();
inlines.add(firstlm);
while (proxyLMiter.hasNext()) {
LayoutManager lm = proxyLMiter.next();
if (lm instanceof InlineLevelLayoutManager) {
inlines.add(lm);
} else {
proxyLMiter.previous();
break;
}
}
llm.addChildLMs(inlines);
return llm;
}
/** {@inheritDoc} */
@Override
public KeepProperty getKeepTogetherProperty() {
return getBlockFO().getKeepTogether();
}
/** {@inheritDoc} */
@Override
public KeepProperty getKeepWithPreviousProperty() {
return getBlockFO().getKeepWithPrevious();
}
/** {@inheritDoc} */
@Override
public KeepProperty getKeepWithNextProperty() {
return getBlockFO().getKeepWithNext();
}
/** {@inheritDoc} */
@Override
public void addAreas(PositionIterator parentIter, LayoutContext layoutContext) {
getParentArea(null);
// if this will create the first block area in a page
// and display-align is after or center, add space before
if (layoutContext.getSpaceBefore() > 0) {
addBlockSpacing(0.0, MinOptMax.getInstance(layoutContext.getSpaceBefore()));
}
LayoutManager childLM;
LayoutManager lastLM = null;
LayoutContext lc = new LayoutContext(0);
lc.setSpaceAdjust(layoutContext.getSpaceAdjust());
// set space after in the LayoutContext for children
if (layoutContext.getSpaceAfter() > 0) {
lc.setSpaceAfter(layoutContext.getSpaceAfter());
}
PositionIterator childPosIter;
// "unwrap" the NonLeafPositions stored in parentIter
// and put them in a new list;
LinkedList<Position> positionList = new LinkedList<Position>();
Position pos;
Position firstPos = null;
Position lastPos = null;
while (parentIter.hasNext()) {
pos = parentIter.next();
//log.trace("pos = " + pos.getClass().getName() + "; " + pos);
if (pos.getIndex() >= 0) {
if (firstPos == null) {
firstPos = pos;
}
lastPos = pos;
}
Position innerPosition = pos;
if (pos instanceof NonLeafPosition) {
//Not all elements are wrapped
innerPosition = pos.getPosition();
}
if (innerPosition != null
&& (innerPosition.getLM() != this
|| innerPosition instanceof MappingPosition)) {
// innerPosition was created by another LM
positionList.add(innerPosition);
lastLM = innerPosition.getLM();
}
}
addId();
addMarkersToPage(true, isFirst(firstPos), isLast(lastPos));
// the Positions in positionList were inside the elements
// created by the LineLM
childPosIter = new PositionIterator(positionList.listIterator());
while ((childLM = childPosIter.getNextChildLM()) != null) {
// set last area flag
lc.setFlags(LayoutContext.LAST_AREA,
(layoutContext.isLastArea() && childLM == lastLM));
lc.setStackLimitBP(layoutContext.getStackLimitBP());
// Add the line areas to Area
childLM.addAreas(childPosIter, lc);
}
addMarkersToPage(false, isFirst(firstPos), isLast(lastPos));
TraitSetter.addSpaceBeforeAfter(curBlockArea, layoutContext.getSpaceAdjust(),
effSpaceBefore, effSpaceAfter);
flush();
curBlockArea = null;
resetSpaces();
//Notify end of block layout manager to the PSLM
checkEndOfLayout(lastPos);
}
/**
* Return an Area which can contain the passed childArea. The childArea
* may not yet have any content, but it has essential traits set.
* In general, if the LayoutManager already has an Area it simply returns
* it. Otherwise, it makes a new Area of the appropriate class.
* It gets a parent area for its area by calling its parent LM.
* Finally, based on the dimensions of the parent area, it initializes
* its own area. This includes setting the content IPD and the maximum
* BPD.
* @param childArea area to get the parent area for
* @return the parent area
*/
@Override
public Area getParentArea(Area childArea) {
if (curBlockArea == null) {
curBlockArea = new Block();
curBlockArea.setIPD(super.getContentAreaIPD());
curBlockArea.setBidiLevel ( getBlockFO().getBidiLevel() );
TraitSetter.addBreaks(curBlockArea,
getBlockFO().getBreakBefore(), getBlockFO().getBreakAfter());
// Must get dimensions from parent area
//Don't optimize this line away. It can have ugly side-effects.
/*Area parentArea =*/ parentLayoutManager.getParentArea(curBlockArea);
// set traits
TraitSetter.setProducerID(curBlockArea, getBlockFO().getId());
TraitSetter.addBorders(curBlockArea,
getBlockFO().getCommonBorderPaddingBackground(),
discardBorderBefore, discardBorderAfter, false, false, this);
TraitSetter.addPadding(curBlockArea,
getBlockFO().getCommonBorderPaddingBackground(),
discardPaddingBefore, discardPaddingAfter, false, false, this);
TraitSetter.addMargins(curBlockArea,
getBlockFO().getCommonBorderPaddingBackground(),
startIndent, endIndent,
this);
setCurrentArea(curBlockArea); // ??? for generic operations
}
return curBlockArea;
}
/** {@inheritDoc} */
@Override
public void addChildArea(Area childArea) {
if (curBlockArea != null) {
if (childArea instanceof LineArea) {
curBlockArea.addLineArea((LineArea) childArea);
} else {
curBlockArea.addBlock((Block) childArea);
}
}
}
/**
* Force current area to be added to parent area.
* {@inheritDoc}
*/
@Override
protected void flush() {
if (curBlockArea != null) {
TraitSetter.addBackground(curBlockArea,
getBlockFO().getCommonBorderPaddingBackground(),
this);
super.flush();
}
}
/**
* convenience method that returns the Block node
* @return the block node
*/
protected org.apache.fop.fo.flow.Block getBlockFO() {
return (org.apache.fop.fo.flow.Block) fobj;
}
// --------- Property Resolution related functions --------- //
/**
* Returns the IPD of the content area
* @return the IPD of the content area
*/
@Override
public int getContentAreaIPD() {
if (curBlockArea != null) {
return curBlockArea.getIPD();
}
return super.getContentAreaIPD();
}
/**
* Returns the BPD of the content area
* @return the BPD of the content area
*/
@Override
public int getContentAreaBPD() {
if (curBlockArea != null) {
return curBlockArea.getBPD();
}
return -1;
}
/** {@inheritDoc} */
@Override
public boolean getGeneratesBlockArea() {
return true;
}
/** {@inheritDoc} */
public void notifySpace(RelSide side, MinOptMax effectiveLength) {
if (RelSide.BEFORE == side) {
if (log.isDebugEnabled()) {
log.debug(this + ": Space " + side + ", "
+ this.effSpaceBefore + "-> " + effectiveLength);
}
this.effSpaceBefore = effectiveLength;
} else {
if (log.isDebugEnabled()) {
log.debug(this + ": Space " + side + ", "
+ this.effSpaceAfter + "-> " + effectiveLength);
}
this.effSpaceAfter = effectiveLength;
}
}
/** {@inheritDoc} */
public void notifyBorder(RelSide side, MinOptMax effectiveLength) {
if (effectiveLength == null) {
if (RelSide.BEFORE == side) {
this.discardBorderBefore = true;
} else {
this.discardBorderAfter = true;
}
}
if (log.isDebugEnabled()) {
log.debug(this + ": Border " + side + " -> " + effectiveLength);
}
}
/** {@inheritDoc} */
public void notifyPadding(RelSide side, MinOptMax effectiveLength) {
if (effectiveLength == null) {
if (RelSide.BEFORE == side) {
this.discardPaddingBefore = true;
} else {
this.discardPaddingAfter = true;
}
}
if (log.isDebugEnabled()) {
log.debug(this + ": Padding " + side + " -> " + effectiveLength);
}
}
/** {@inheritDoc} */
@Override
public boolean isRestartable() {
return true;
}
public int getBreakBefore() {
return BreakOpportunityHelper.getBreakBefore(this);
}
}