/*
 * Copyright 1999-2006 The Apache Software Foundation.
 * 
 * Licensed 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.area.inline;

import org.apache.fop.area.Area;

import java.util.List;
import java.util.ArrayList;

/**
 * Inline parent area.
 * This is an inline area that can have other inlines as children.
 */
public class InlineParent extends InlineArea {
    /**
     * The list of inline areas added to this inline parent.
     */
    protected List inlines = new ArrayList();

    /** Controls whether the IPD is automatically adjusted based on the area's children. */
    protected transient boolean autoSize;
    
    /**
     * Create a new inline parent to add areas to.
     */
    public InlineParent() {
    }

    /**
     * Override generic Area method.
     *
     * @param childArea the child area to add
     */
    public void addChildArea(Area childArea) {
        if (inlines.size() == 0) {
            autoSize = (getIPD() == 0);
        }
        if (childArea instanceof InlineArea) {
            inlines.add(childArea);
            if (autoSize) {
                increaseIPD(((InlineArea) childArea).getAllocIPD());
            }
        }
    }

    /**
     * Get the child areas for this inline parent.
     *
     * @return the list of child areas
     */
    public List getChildAreas() {
        return inlines;
    }

    /**
     * recursively apply the variation factor to all descendant areas
     * @param variationFactor the variation factor that must be applied to adjustments
     * @param lineStretch     the total stretch of the line
     * @param lineShrink      the total shrink of the line
     * @return true if there is an UnresolvedArea descendant
     */
    public boolean applyVariationFactor(double variationFactor,
                                        int lineStretch, int lineShrink) {
        boolean bUnresolvedAreasPresent = false;
        // recursively apply variation factor to descendant areas 
        for (int i = 0, len = inlines.size(); i < len; i++) {
            bUnresolvedAreasPresent |= ((InlineArea)inlines.get(i))
                .applyVariationFactor(variationFactor, lineStretch, lineShrink);
        }
        return bUnresolvedAreasPresent;
    }
}