/*
* 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: StaticContentLayoutManager.java 635508 2008-03-10 10:06:37Z jeremias $ */
package org.apache.fop.layoutmgr;
import java.util.LinkedList;
import java.util.List;
import java.util.ListIterator;
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.RegionReference;
import org.apache.fop.fo.FONode;
import org.apache.fop.fo.pagination.PageSequence;
import org.apache.fop.fo.pagination.SideRegion;
import org.apache.fop.fo.pagination.StaticContent;
import org.apache.fop.layoutmgr.inline.InlineLevelLayoutManager;
import org.apache.fop.layoutmgr.inline.TextLayoutManager;
import org.apache.fop.traits.MinOptMax;
/**
* LayoutManager for an fo:flow object.
* Its parent LM is the PageSequenceLayoutManager.
* This LM is responsible for getting columns of the appropriate size
* and filling them with block-level areas generated by its children.
*/
public class StaticContentLayoutManager extends BlockStackingLayoutManager {
/**
* logging instance
*/
private static Log log = LogFactory.getLog(StaticContentLayoutManager.class);
private RegionReference targetRegion;
private Block targetBlock;
private SideRegion regionFO;
private int contentAreaIPD = 0;
private int contentAreaBPD = -1;
/**
* Creates a new StaticContentLayoutManager.
* @param pslm PageSequenceLayoutManager this layout manager belongs to
* @param node static-content FO
* @param reg side region to layout into
*/
public StaticContentLayoutManager(PageSequenceLayoutManager pslm,
StaticContent node, SideRegion reg) {
super(node);
setParent(pslm);
regionFO = reg;
targetRegion = getCurrentPV().getRegionReference(regionFO.getNameId());
}
/**
* Creates a new StaticContentLayoutManager.
* @param pslm PageSequenceLayoutManager this layout manager belongs to
* @param node static-content FO
* @param block the block to layout into
*/
public StaticContentLayoutManager(PageSequenceLayoutManager pslm,
StaticContent node, Block block) {
super(node);
setParent(pslm);
targetBlock = block;
}
/** {@inheritDoc} */
public LinkedList getNextKnuthElements(LayoutContext context, int alignment) {
if (true) {
throw new UnsupportedOperationException(
"Shouldn't this method be emptied because it's never called at all?");
}
//TODO Empty this method?!?
// set layout dimensions
setContentAreaIPD(context.getRefIPD());
setContentAreaBPD(context.getStackLimitBP().opt);
//TODO Copied from elsewhere. May be worthwhile to factor out the common parts.
// currently active LM
BlockLevelLayoutManager curLM;
BlockLevelLayoutManager prevLM = null;
MinOptMax stackSize = new MinOptMax();
LinkedList returnedList;
LinkedList returnList = new LinkedList();
while ((curLM = ((BlockLevelLayoutManager) getChildLM())) != null) {
if (curLM instanceof InlineLevelLayoutManager) {
log.error("inline area not allowed under flow - ignoring");
curLM.setFinished(true);
continue;
}
// Set up a LayoutContext
MinOptMax bpd = context.getStackLimitBP();
LayoutContext childLC = new LayoutContext(0);
childLC.setStackLimitBP(MinOptMax.subtract(bpd, stackSize));
childLC.setRefIPD(context.getRefIPD());
// get elements from curLM
returnedList = curLM.getNextKnuthElements(childLC, alignment);
//log.debug("FLM.getNextKnuthElements> returnedList.size() = "
// + returnedList.size());
// "wrap" the Position inside each element
LinkedList tempList = returnedList;
KnuthElement tempElement;
returnedList = new LinkedList();
ListIterator listIter = tempList.listIterator();
while (listIter.hasNext()) {
tempElement = (KnuthElement)listIter.next();
tempElement.setPosition(new NonLeafPosition(this, tempElement.getPosition()));
returnedList.add(tempElement);
}
if (returnedList.size() == 1
&& ((KnuthElement)returnedList.getFirst()).isPenalty()
&& ((KnuthPenalty)returnedList.getFirst()).getP() == -KnuthElement.INFINITE) {
// a descendant of this flow has break-before
returnList.addAll(returnedList);
return returnList;
} else {
if (returnList.size() > 0) {
// there is a block before this one
if (prevLM.mustKeepWithNext()
|| curLM.mustKeepWithPrevious()) {
// add an infinite penalty to forbid a break between blocks
returnList.add(new KnuthPenalty(0,
KnuthElement.INFINITE, false,
new Position(this), false));
} else if (!((KnuthElement) returnList.getLast()).isGlue()) {
// add a null penalty to allow a break between blocks
returnList.add(new KnuthPenalty(0, 0, false, new Position(this), false));
}
}
/*LF*/ if (returnedList.size() > 0) { // controllare!
returnList.addAll(returnedList);
if (((KnuthElement)returnedList.getLast()).isPenalty()
&& ((KnuthPenalty)returnedList.getLast()).getP()
== -KnuthElement.INFINITE) {
// a descendant of this flow has break-after
/*LF*/ //log.debug("FLM - break after!!");
return returnList;
}
/*LF*/ }
}
prevLM = curLM;
}
setFinished(true);
if (returnList.size() > 0) {
return returnList;
} else {
return null;
}
}
/**
* {@inheritDoc}
*/
public void addAreas(PositionIterator parentIter, LayoutContext layoutContext) {
AreaAdditionUtil.addAreas(this, parentIter, layoutContext);
flush();
targetRegion = null;
}
/**
* Add child area to a the correct container, depending on its
* area class. A Flow can fill at most one area container of any class
* at any one time. The actual work is done by BlockStackingLM.
* {@inheritDoc}
*/
public void addChildArea(Area childArea) {
if (getStaticContentFO().getFlowName().equals("xsl-footnote-separator")) {
targetBlock.addBlock((Block)childArea);
} else {
targetRegion.addBlock((Block)childArea);
}
}
/**
* {@inheritDoc}
*/
public Area getParentArea(Area childArea) {
if (getStaticContentFO().getFlowName().equals("xsl-footnote-separator")) {
return targetBlock;
} else {
return targetRegion;
}
}
/**
* Does the layout for a side region. Called by PageSequenceLayoutManager.
*/
public void doLayout() {
int targetIPD = 0;
int targetBPD = 0;
int targetAlign = EN_AUTO;
boolean autoHeight = false;
StaticContentBreaker breaker;
if (getStaticContentFO().getFlowName().equals("xsl-footnote-separator")) {
targetIPD = targetBlock.getIPD();
targetBPD = targetBlock.getBPD();
if (targetBPD == 0) {
autoHeight = true;
}
targetAlign = EN_BEFORE;
} else {
targetIPD = targetRegion.getIPD();
targetBPD = targetRegion.getBPD();
targetAlign = regionFO.getDisplayAlign();
}
setContentAreaIPD(targetIPD);
setContentAreaBPD(targetBPD);
breaker = new StaticContentBreaker(this, targetIPD, targetAlign);
breaker.doLayout(targetBPD, autoHeight);
if (breaker.isOverflow()) {
if (!autoHeight) {
//Overflow handling
if (regionFO.getOverflow() == EN_ERROR_IF_OVERFLOW) {
//TODO throw layout exception
}
log.warn(FONode.decorateWithContextInfo(
"static-content overflows the available area.", fobj));
}
}
}
/**
* Convenience method that returns the Static Content node.
* @return the static content node
*/
protected StaticContent getStaticContentFO() {
return (StaticContent) fobj;
}
private class StaticContentBreaker extends AbstractBreaker {
private StaticContentLayoutManager lm;
private int displayAlign;
private int ipd;
private boolean overflow = false;
public StaticContentBreaker(StaticContentLayoutManager lm, int ipd,
int displayAlign) {
this.lm = lm;
this.ipd = ipd;
this.displayAlign = displayAlign;
}
/** {@inheritDoc} */
protected void observeElementList(List elementList) {
String elementListID = getStaticContentFO().getFlowName();
String pageSequenceID = ((PageSequence)lm.getParent().getFObj()).getId();
if (pageSequenceID != null && pageSequenceID.length() > 0) {
elementListID += "-" + pageSequenceID;
}
ElementListObserver.observe(elementList, "static-content", elementListID);
}
/** {@inheritDoc} */
protected boolean isPartOverflowRecoveryActivated() {
//For side regions, this must be disabled because of wanted overflow.
return false;
}
public boolean isOverflow() {
return this.overflow;
}
protected LayoutManager getTopLevelLM() {
return lm;
}
protected LayoutContext createLayoutContext() {
LayoutContext lc = super.createLayoutContext();
lc.setRefIPD(ipd);
return lc;
}
protected LinkedList getNextKnuthElements(LayoutContext context, int alignment) {
LayoutManager curLM; // currently active LM
LinkedList returnList = new LinkedList();
while ((curLM = getChildLM()) != null) {
LayoutContext childLC = new LayoutContext(0);
childLC.setStackLimitBP(context.getStackLimitBP());
childLC.setRefIPD(context.getRefIPD());
childLC.setWritingMode(context.getWritingMode());
LinkedList returnedList = null;
//The following is a HACK! Ignore leading and trailing white space
boolean ignore = curLM instanceof TextLayoutManager;
if (!curLM.isFinished()) {
returnedList = curLM.getNextKnuthElements(childLC, alignment);
}
if (returnedList != null && !ignore) {
lm.wrapPositionElements(returnedList, returnList);
}
}
SpaceResolver.resolveElementList(returnList);
setFinished(true);
return returnList;
}
protected int getCurrentDisplayAlign() {
return displayAlign;
}
protected boolean hasMoreContent() {
return !lm.isFinished();
}
protected void addAreas(PositionIterator posIter, LayoutContext context) {
AreaAdditionUtil.addAreas(lm, posIter, context);
}
protected void doPhase3(PageBreakingAlgorithm alg, int partCount,
BlockSequence originalList, BlockSequence effectiveList) {
if (partCount > 1) {
overflow = true;
}
//Rendering all parts (not just the first) at once for the case where the parts that
//overflow should be visible.
alg.removeAllPageBreaks();
//Directly add areas after finding the breaks
this.addAreas(alg, 1, originalList, effectiveList);
}
protected void finishPart(PageBreakingAlgorithm alg, PageBreakPosition pbp) {
//nop for static content
}
protected LayoutManager getCurrentChildLM() {
return null; //TODO NYI
}
}
/**
* Returns the IPD of the content area
* @return the IPD of the content area
*/
public int getContentAreaIPD() {
return contentAreaIPD;
}
/** {@inheritDoc} */
protected void setContentAreaIPD(int contentAreaIPD) {
this.contentAreaIPD = contentAreaIPD;
}
/**
* Returns the BPD of the content area
* @return the BPD of the content area
*/
public int getContentAreaBPD() {
return contentAreaBPD;
}
private void setContentAreaBPD(int contentAreaBPD) {
this.contentAreaBPD = contentAreaBPD;
}
}