/*
 * 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: TableCaptionLayoutManager.java 1537600 2013-10-31 19:44:25Z gadams $ */

package org.apache.fop.layoutmgr.table;

import org.apache.fop.area.Area;
import org.apache.fop.area.Block;
import org.apache.fop.fo.flow.table.TableCaption;
import org.apache.fop.layoutmgr.BlockStackingLayoutManager;
import org.apache.fop.layoutmgr.Keep;
import org.apache.fop.layoutmgr.LayoutContext;
import org.apache.fop.layoutmgr.PositionIterator;

LayoutManager for a table-caption FO.
The table caption contains blocks that are placed beside the
table.
TODO Implement getNextKnuthElements()
/**
 * LayoutManager for a table-caption FO.
 * The table caption contains blocks that are placed beside the
 * table.
 * TODO Implement getNextKnuthElements()
 */
public class TableCaptionLayoutManager extends BlockStackingLayoutManager {

    private Block curBlockArea;

    //private List childBreaks = new ArrayList();

    
Create a new Caption layout manager.
Params:
node – table-caption FO/**
     * Create a new Caption layout manager.
     * @param node table-caption FO
     */
    public TableCaptionLayoutManager(TableCaption node) {
        super(node);
    }

    
Returns:
the table-caption FO/** @return the table-caption FO */
    public TableCaption getTableCaptionFO() {
        return (TableCaption)this.fobj;
    }

    /**
     * Get the next break position for the caption.
     *
     * @param context the layout context for finding breaks
     * @return the next break possibility
     */
    /*
    public BreakPoss getNextBreakPoss(LayoutContext context) {
        LayoutManager curLM; // currently active LM

        MinOptMax stackSize = new MinOptMax();
        // if starting add space before
        // stackSize.add(spaceBefore);
        BreakPoss lastPos = null;

        // if there is a caption then get the side and work out when
        // to handle it

        while ((curLM = getChildLM()) != null) {
            // Make break positions and return blocks!
            // Set up a LayoutContext
            int ipd = context.getRefIPD();
            BreakPoss bp;

            LayoutContext childLC = LayoutContext.newInstance();
            // if line layout manager then set stack limit to ipd
            // line LM actually generates a LineArea which is a block
            childLC.setStackLimit(
                  MinOptMax.subtract(context.getStackLimit(),
                                     stackSize));
            childLC.setRefIPD(ipd);

            boolean over = false;

            while (!curLM.isFinished()) {
                if ((bp = curLM.getNextBreakPoss(childLC)) != null) {
                    if (stackSize.opt + bp.getStackingSize().opt > context.getStackLimit().max) {
                        // reset to last break
                        if (lastPos != null) {
                            LayoutManager lm = lastPos.getLayoutManager();
                            lm.resetPosition(lastPos.getPosition());
                            if (lm != curLM) {
                                curLM.resetPosition(null);
                            }
                        } else {
                            curLM.resetPosition(null);
                        }
                        over = true;
                        break;
                    }
                    stackSize.add(bp.getStackingSize());
                    lastPos = bp;
                    childBreaks.add(bp);

                    if (bp.nextBreakOverflows()) {
                        over = true;
                        break;
                    }

                    childLC.setStackLimit(MinOptMax.subtract(
                                             context.getStackLimit(), stackSize));
                }
            }
            BreakPoss breakPoss = new BreakPoss(
                                    new LeafPosition(this, childBreaks.size() - 1));
            if (over) {
                breakPoss.setFlag(BreakPoss.NEXT_OVERFLOWS, true);
            }
            breakPoss.setStackingSize(stackSize);
            return breakPoss;
        }
        setFinished(true);
        return null;
    }*/

    
Add the areas to the parent.
Params:
parentIter – the position iterator of the breaks
layoutContext – the layout context for adding areas/**
     * Add the areas to the parent.
     *
     * @param parentIter the position iterator of the breaks
     * @param layoutContext the layout context for adding areas
     */
    public void addAreas(PositionIterator parentIter,
                         LayoutContext layoutContext) {
        getParentArea(null);
        addId();

        /* TODO: Reimplement using Knuth approach
        LayoutManager childLM;
        int iStartPos = 0;
        LayoutContext lc = LayoutContext.newInstance();
        while (parentIter.hasNext()) {
            LeafPosition lfp = (LeafPosition) parentIter.next();
            // Add the block areas to Area
            PositionIterator breakPosIter = new BreakPossPosIter(
                    childBreaks, iStartPos, lfp.getLeafPos() + 1);
            iStartPos = lfp.getLeafPos() + 1;
            while ((childLM = breakPosIter.getNextChildLM()) != null) {
                childLM.addAreas(breakPosIter, lc);
            }
        }*/

        flush();

        //childBreaks.clear();
        curBlockArea = null;
    }

    
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.
Params:
childArea – the child area
Returns:
the parent area from this caption/**
     * 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 the child area
     * @return the parent area from this caption
     */
    public Area getParentArea(Area childArea) {
        if (curBlockArea == null) {
            curBlockArea = new Block();
            // Set up dimensions
            // Must get dimensions from parent area
            Area parentArea = parentLayoutManager.getParentArea(curBlockArea);
            int referenceIPD = parentArea.getIPD();
            curBlockArea.setIPD(referenceIPD);
            curBlockArea.setBidiLevel(getTableCaptionFO().getBidiLevel());
            // Get reference IPD from parentArea
            setCurrentArea(curBlockArea); // ??? for generic operations
        }
        return curBlockArea;
    }

    
Add the child to the caption area.
Params:
childArea – the child area to add/**
     * Add the child to the caption area.
     *
     * @param childArea the child area to add
     */
    public void addChildArea(Area childArea) {
        if (curBlockArea != null) {
                curBlockArea.addBlock((Block) childArea);
        }
    }

    
{@inheritDoc} /** {@inheritDoc} */
    public Keep getKeepWithNext() {
        return Keep.KEEP_AUTO;
        /* TODO Complete me!
        return KeepUtil.getCombinedBlockLevelKeepStrength(
                getTableCaptionFO().getKeepWithNext());
        */
    }

    
{@inheritDoc} /** {@inheritDoc} */
    public Keep getKeepWithPrevious() {
        return Keep.KEEP_AUTO;
        /* TODO Complete me!
        return KeepUtil.getCombinedBlockLevelKeepStrength(
                getTableCaptionFO().getKeepWithPrevious());
        */
    }

}