/*
* 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: CorrespondingPropertyMaker.java 1293736 2012-02-26 02:29:01Z gadams $ */
package org.apache.fop.fo.properties;
import org.apache.fop.fo.FObj;
import org.apache.fop.fo.PropertyList;
import org.apache.fop.fo.expr.PropertyException;
/**
* Maker class for handling corresponding properties.
*/
public class CorrespondingPropertyMaker {
/** base property maker */
protected PropertyMaker baseMaker;
/** corresponding property for lr-tb writing mode */
protected int lrtb;
/** corresponding property for rl-tb writing mode */
protected int rltb;
/** corresponding property for tb-rl writing mode */
protected int tbrl;
/** corresponding property for tb-lr writing mode */
protected int tblr;
/** user parent property list */
protected boolean useParent;
private boolean relative;
/**
* Construct a corresponding property maker.
* @param baseMaker the base property maker
*/
public CorrespondingPropertyMaker(PropertyMaker baseMaker) {
this.baseMaker = baseMaker;
baseMaker.setCorresponding(this);
}
/**
* Set corresponding property values.
* @param lrtb a corresponding value
* @param rltb a corresponding value
* @param tbrl a corresponding value
* @param tblr a corresponding value
*/
/**
* Set corresponding property identifiers.
* @param lrtb the property that corresponds with lr-tb writing mode
* @param rltb the property that corresponds with rl-tb writing mode
* @param tbrl the property that corresponds with tb-lr writing mode
* @param tblr the property that corresponds with tb-lr writing mode
*/
public void setCorresponding(int lrtb, int rltb, int tbrl, int tblr) {
this.lrtb = lrtb;
this.rltb = rltb;
this.tbrl = tbrl;
this.tblr = tblr;
}
/**
* Controls whether the PropertyMaker accesses the parent property list or the current
* property list for determining the writing mode.
* @param useParent true if the parent property list should be used.
*/
public void setUseParent(boolean useParent) {
this.useParent = useParent;
}
/**
* Set relative flag.
* @param relative true if properties operate on a relative direction
*/
public void setRelative(boolean relative) {
this.relative = relative;
}
/**
* For properties that operate on a relative direction (before, after,
* start, end) instead of an absolute direction (top, bottom, left,
* right), this method determines whether a corresponding property
* is specified on the corresponding absolute direction. For example,
* the border-start-color property in a lr-tb writing-mode specifies
* the same thing that the border-left-color property specifies. In this
* example, if the Maker for the border-start-color property is testing,
* and if the border-left-color is specified in the properties,
* this method should return true.
* @param propertyList collection of properties to be tested
* @return true iff 1) the property operates on a relative direction,
* AND 2) the property has a corresponding property on an absolute
* direction, AND 3) the corresponding property on that absolute
* direction has been specified in the input properties
*/
public boolean isCorrespondingForced(PropertyList propertyList) {
if (!relative) {
return false;
}
PropertyList pList = getWMPropertyList(propertyList);
if (pList != null) {
int correspondingId = pList.selectFromWritingMode(lrtb, rltb, tbrl, tblr);
if (pList.getExplicit(correspondingId) != null) {
return true;
}
}
return false;
}
/**
* Return a Property object representing the value of this property,
* based on other property values for this FO.
* A special case is properties which inherit the specified value,
* rather than the computed value.
* @param propertyList The PropertyList for the FO.
* @return Property A computed Property value or null if no rules
* are specified (in foproperties.xml) to compute the value.
* @throws PropertyException if a property exception occurs
*/
public Property compute(PropertyList propertyList) throws PropertyException {
PropertyList pList = getWMPropertyList(propertyList);
if (pList == null) {
return null;
}
int correspondingId = pList.selectFromWritingMode(lrtb, rltb, tbrl, tblr);
Property p = propertyList.getExplicitOrShorthand(correspondingId);
if (p != null) {
FObj parentFO = propertyList.getParentFObj();
p = baseMaker.convertProperty(p, propertyList, parentFO);
}
return p;
}
/**
* Return the property list to use for fetching writing mode depending property
* ids.
* @param pList a property list
* @return the property list to use
*/
protected PropertyList getWMPropertyList(PropertyList pList) {
if (useParent) {
return pList.getParentPropertyList();
} else {
return pList;
}
}
}