/*
* 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.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.fop.area.AreaTreeHandler;
import org.apache.fop.area.AreaTreeModel;
import org.apache.fop.area.IDTracker;
import org.apache.fop.area.PageViewport;
import org.apache.fop.area.Resolvable;
import org.apache.fop.datatypes.Numeric;
import org.apache.fop.fo.Constants;
import org.apache.fop.fo.flow.Marker;
import org.apache.fop.fo.flow.RetrieveMarker;
import org.apache.fop.fo.pagination.AbstractPageSequence;
/**
* Abstract base class for a page sequence layout manager.
*/
public abstract class AbstractPageSequenceLayoutManager extends AbstractLayoutManager
implements TopLevelLayoutManager {
private static Log log = LogFactory.getLog(AbstractPageSequenceLayoutManager.class);
/**
* AreaTreeHandler which activates the PSLM and controls
* the rendering of its pages.
*/
protected AreaTreeHandler areaTreeHandler;
/** ID tracker supplied by the AreaTreeHandler */
protected IDTracker idTracker;
/** page sequence formatting object being processed by this class */
protected AbstractPageSequence pageSeq;
/** Current page with page-viewport-area being filled by the PSLM. */
protected Page curPage;
/** the current page number */
protected int currentPageNum;
/** The stating page number */
protected int startPageNum;
/**
* Constructor
*
* @param ath the area tree handler object
* @param pseq fo:page-sequence to process
*/
public AbstractPageSequenceLayoutManager(AreaTreeHandler ath, AbstractPageSequence pseq) {
super(pseq);
this.areaTreeHandler = ath;
this.idTracker = ath.getIDTracker();
this.pageSeq = pseq;
}
/**
* @return the LayoutManagerMaker object associated to the areaTreeHandler
*/
public LayoutManagerMaker getLayoutManagerMaker() {
return areaTreeHandler.getLayoutManagerMaker();
}
/**
* Provides access to the current page.
* @return the current Page
*/
public Page getCurrentPage() {
return curPage;
}
/**
* Provides access for setting the current page.
* @param currentPage the new current Page
*/
protected void setCurrentPage(Page currentPage) {
this.curPage = currentPage;
}
/**
* Provides access to the current page number
* @return the current page number
*/
protected int getCurrentPageNum() {
return currentPageNum;
}
/** {@inheritDoc} */
public void initialize() {
startPageNum = pageSeq.getStartingPageNumber();
currentPageNum = startPageNum - 1;
curPage = null;
}
/**
* This returns the first PageViewport that contains an id trait
* matching the idref argument, or null if no such PV exists.
*
* @param idref the idref trait needing to be resolved
* @return the first PageViewport that contains the ID trait
*/
public PageViewport getFirstPVWithID(String idref) {
List list = idTracker.getPageViewportsContainingID(idref);
if (list != null && list.size() > 0) {
return (PageViewport) list.get(0);
}
return null;
}
/**
* This returns the last PageViewport that contains an id trait
* matching the idref argument, or null if no such PV exists.
*
* @param idref the idref trait needing to be resolved
* @return the last PageViewport that contains the ID trait
*/
public PageViewport getLastPVWithID(String idref) {
List list = idTracker.getPageViewportsContainingID(idref);
if (list != null && list.size() > 0) {
return (PageViewport) list.get(list.size() - 1);
}
return null;
}
/**
* Add an ID reference to the current page.
* When adding areas the area adds its ID reference.
* For the page layout manager it adds the id reference
* with the current page to the area tree.
*
* @param id the ID reference to add
*/
public void addIDToPage(String id) {
if (id != null && id.length() > 0) {
idTracker.associateIDWithPageViewport(id, curPage.getPageViewport());
}
}
/**
* Add an id reference of the layout manager in the AreaTreeHandler,
* if the id hasn't been resolved yet
* @param id the id to track
* @return a boolean indicating if the id has already been resolved
* TODO Maybe give this a better name
*/
public boolean associateLayoutManagerID(String id) {
if (log.isDebugEnabled()) {
log.debug("associateLayoutManagerID(" + id + ")");
}
if (!idTracker.alreadyResolvedID(id)) {
idTracker.signalPendingID(id);
return false;
} else {
return true;
}
}
/**
* Notify the areaTreeHandler that the LayoutManagers containing
* idrefs have finished creating areas
* @param id the id for which layout has finished
*/
public void notifyEndOfLayout(String id) {
idTracker.signalIDProcessed(id);
}
/**
* Identify an unresolved area (one needing an idref to be
* resolved, e.g. the internal-destination of an fo:basic-link)
* for both the AreaTreeHandler and PageViewport object.
*
* The IDTracker keeps a document-wide list of idref's
* and the PV's needing them to be resolved. It uses this to
* send notifications to the PV's when an id has been resolved.
*
* The PageViewport keeps lists of id's needing resolving, along
* with the child areas (page-number-citation, basic-link, etc.)
* of the PV needing their resolution.
*
* @param id the ID reference to add
* @param res the resolvable object that needs resolving
*/
public void addUnresolvedArea(String id, Resolvable res) {
curPage.getPageViewport().addUnresolvedIDRef(id, res);
idTracker.addUnresolvedIDRef(id, curPage.getPageViewport());
}
/**
* Bind the RetrieveMarker to the corresponding Marker subtree.
* If the boundary is page then it will only check the
* current page. For page-sequence and document it will
* lookup preceding pages from the area tree and try to find
* a marker.
* If we retrieve a marker from a preceding page,
* then the containing page does not have a qualifying area,
* and all qualifying areas have ended.
* Therefore we use last-ending-within-page (Constants.EN_LEWP)
* as the position.
*
* @param rm the RetrieveMarker instance whose properties are to
* used to find the matching Marker.
* @return a bound RetrieveMarker instance, or null if no Marker
* could be found.
*/
public RetrieveMarker resolveRetrieveMarker(RetrieveMarker rm) {
AreaTreeModel areaTreeModel = areaTreeHandler.getAreaTreeModel();
String name = rm.getRetrieveClassName();
int boundary = rm.getRetrieveBoundary();
// get marker from the current markers on area tree
Marker mark = getCurrentPV().resolveMarker(rm);
if (mark == null && boundary != EN_PAGE) {
// go back over pages until mark found
// if document boundary then keep going
boolean doc = (boundary == EN_DOCUMENT);
int seq = areaTreeModel.getPageSequenceCount();
int page = areaTreeModel.getPageCount(seq) - 1;
while (page < 0 && doc && seq > 1) {
seq--;
page = areaTreeModel.getPageCount(seq) - 1;
}
while (page >= 0) {
PageViewport pv = areaTreeModel.getPage(seq, page);
int originalPosition = rm.getPosition();
rm.changePositionTo(Constants.EN_LEWP);
mark = pv.resolveMarker(rm);
// this is probably not necessary since the RM will not be used again, but to be safe...
rm.changePositionTo(originalPosition);
if (mark != null) {
break;
}
page--;
if (page < 0 && doc && seq > 1) {
seq--;
page = areaTreeModel.getPageCount(seq) - 1;
}
}
}
if (mark == null) {
log.debug("found no marker with name: " + name);
return null;
} else {
rm.bindMarker(mark);
return rm;
}
}
/**
* Creates and returns a new page.
* @param pageNumber the page number
* @param isBlank true if it's a blank page
* @return the newly created page
*/
protected abstract Page createPage(int pageNumber, boolean isBlank);
/**
* Makes a new page
*
* @param isBlank whether this page is blank or not
* @return a new page
*/
protected Page makeNewPage(boolean isBlank) {
if (curPage != null) {
finishPage();
}
currentPageNum++;
curPage = createPage(currentPageNum, isBlank);
if (log.isDebugEnabled()) {
log.debug("[" + curPage.getPageViewport().getPageNumberString()
+ (isBlank ? "*" : "") + "]");
}
addIDToPage(pageSeq.getRoot().getId());
addIDToPage(pageSeq.getId());
return curPage;
}
/**
* Finishes a page in preparation for a new page.
*/
protected void finishPage() {
if (log.isTraceEnabled()) {
curPage.getPageViewport().dumpMarkers();
}
// Try to resolve any unresolved IDs for the current page.
//
idTracker.tryIDResolution(curPage.getPageViewport());
// Queue for ID resolution and rendering
areaTreeHandler.getAreaTreeModel().addPage(curPage.getPageViewport());
if (log.isDebugEnabled()) {
log.debug("page finished: " + curPage.getPageViewport().getPageNumberString()
+ ", current num: " + currentPageNum);
}
curPage = null;
}
/** {@inheritDoc} */
public void doForcePageCount(Numeric nextPageSeqInitialPageNumber) {
int forcePageCount = pageSeq.getForcePageCount();
// xsl-spec version 1.0 (15.oct 2001)
// auto | even | odd | end-on-even | end-on-odd | no-force | inherit
// auto:
// Force the last page in this page-sequence to be an odd-page
// if the initial-page-number of the next page-sequence is even.
// Force it to be an even-page
// if the initial-page-number of the next page-sequence is odd.
// If there is no next page-sequence
// or if the value of its initial-page-number is "auto" do not force any page.
// if force-page-count is auto then set the value of forcePageCount
// depending on the initial-page-number of the next page-sequence
if (nextPageSeqInitialPageNumber != null && forcePageCount == Constants.EN_AUTO) {
if (nextPageSeqInitialPageNumber.getEnum() != 0) {
// auto | auto-odd | auto-even
int nextPageSeqPageNumberType = nextPageSeqInitialPageNumber.getEnum();
if (nextPageSeqPageNumberType == Constants.EN_AUTO_ODD) {
forcePageCount = Constants.EN_END_ON_EVEN;
} else if (nextPageSeqPageNumberType == Constants.EN_AUTO_EVEN) {
forcePageCount = Constants.EN_END_ON_ODD;
} else { // auto
forcePageCount = Constants.EN_NO_FORCE;
}
} else { // <integer> for explicit page number
int nextPageSeqPageStart = nextPageSeqInitialPageNumber.getValue();
// spec rule
nextPageSeqPageStart = (nextPageSeqPageStart > 0) ? nextPageSeqPageStart : 1;
if (nextPageSeqPageStart % 2 == 0) { // explicit even startnumber
forcePageCount = Constants.EN_END_ON_ODD;
} else { // explicit odd startnumber
forcePageCount = Constants.EN_END_ON_EVEN;
}
}
}
if (forcePageCount == Constants.EN_EVEN) {
if ((currentPageNum - startPageNum + 1) % 2 != 0) { // we have an odd number of pages
curPage = makeNewPage(true);
}
} else if (forcePageCount == Constants.EN_ODD) {
if ((currentPageNum - startPageNum + 1) % 2 == 0) { // we have an even number of pages
curPage = makeNewPage(true);
}
} else if (forcePageCount == Constants.EN_END_ON_EVEN) {
if (currentPageNum % 2 != 0) { // we are now on an odd page
curPage = makeNewPage(true);
}
} else if (forcePageCount == Constants.EN_END_ON_ODD) {
if (currentPageNum % 2 == 0) { // we are now on an even page
curPage = makeNewPage(true);
}
} /* else if (forcePageCount == Constants.EN_NO_FORCE) {
// i hope: nothing special at all
} */
if (curPage != null) {
finishPage();
}
while (forcePageCount != Constants.EN_NO_FORCE && getCurrentPageNum() < getLastPageNumber()) {
curPage = makeNewPage(true);
finishPage();
}
}
/** {@inheritDoc} */
public void reset() {
throw new IllegalStateException();
}
protected int getLastPageNumber() {
return currentPageNum;
}
}