/*
 * 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: UnresolvedPageNumber.java 1617052 2014-08-10 06:55:01Z gadams $ */

package org.apache.fop.area.inline;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.util.List;

import org.apache.fop.area.PageViewport;
import org.apache.fop.area.Resolvable;
import org.apache.fop.complexscripts.bidi.InlineRun;
import org.apache.fop.fonts.Font;

Unresolvable page number area.
This is a word area that resolves itself to a page number
from an id reference.
/**
 * Unresolvable page number area.
 * This is a word area that resolves itself to a page number
 * from an id reference.
 */
public class UnresolvedPageNumber extends TextArea implements Resolvable {


    private static final long serialVersionUID = -1758090835371647980L;

    private boolean resolved;
    private String pageIDRef;
    private String text;
    private boolean pageType;

    
Indicates that the reference refers to the first area generated by a formatting object. /** Indicates that the reference refers to the first area generated by a formatting object. */
    public static final boolean FIRST = true;
    
Indicates that the reference refers to the last area generated by a formatting object. /** Indicates that the reference refers to the last area generated by a formatting object. */
    public static final boolean LAST = false;

    //Transient fields
    private transient Font font;

    public UnresolvedPageNumber() {
        this(null, null, FIRST);
    }

    
Create a new unresolved page number.
Params:
id – the id reference for resolving this
f –  the font for formatting the page number/**
     * Create a new unresolved page number.
     *
     * @param id the id reference for resolving this
     * @param f  the font for formatting the page number
     */
    public UnresolvedPageNumber(String id, Font f) {
        this(id, f, FIRST);
    }

    
Create a new unresolved page number.
Params:
id –   the id reference for resolving this
f –    the font for formatting the page number
type – indicates whether the reference refers to the first or last area generated by
            a formatting object/**
     * Create a new unresolved page number.
     *
     * @param id   the id reference for resolving this
     * @param f    the font for formatting the page number
     * @param type indicates whether the reference refers to the first or last area generated by
     *             a formatting object
     */
    public UnresolvedPageNumber(String id, Font f, boolean type) {
        pageIDRef = id;
        font = f;
        text = "?";
        pageType = type;
    }

    private void readObject(ObjectInputStream ois) throws ClassNotFoundException, IOException {
        ois.defaultReadObject();
    }

    
Get the id references for this area.
Returns:
the id reference for this unresolved page number/**
     * Get the id references for this area.
     *
     * @return the id reference for this unresolved page number
     */
    public String[] getIDRefs() {
        return new String[] {pageIDRef};
    }

    
Get the (resolved or unresolved) text.
Returns:
the text/**
     * Get the (resolved or unresolved) text.
     *
     * @return the text
     */
    public String getText() {
        return text;
    }

    
Resolve the page number idref
This resolves the idref for this object by getting the page number
string from the first page in the list of pages that apply
for this ID.  The page number text is then set to the String value
of the page number.
TODO: [GA] May need to run bidi algorithm and script processor
on resolved page number.
Params:
id – an id whose PageViewports have been determined
pages – the list of PageViewports associated with this ID/**
     * Resolve the page number idref
     * This resolves the idref for this object by getting the page number
     * string from the first page in the list of pages that apply
     * for this ID.  The page number text is then set to the String value
     * of the page number.
     *
     * TODO: [GA] May need to run bidi algorithm and script processor
     * on resolved page number.
     *
     * @param id an id whose PageViewports have been determined
     * @param pages the list of PageViewports associated with this ID
     */
    public void resolveIDRef(String id, List<PageViewport> pages) {
        if (!resolved && pageIDRef.equals(id) && pages != null) {
            if (log.isDebugEnabled()) {
                log.debug("Resolving pageNumber: " + id);
            }
            resolved = true;
            int pageIndex = pageType ? 0 : pages.size() - 1;
            PageViewport page = pages.get(pageIndex);
            // replace the text
            removeText();
            text = page.getPageNumberString();
            addWord(text, 0, getBidiLevel());
            // update ipd
            if (font != null) {
                handleIPDVariation(font.getWordWidth(text) - getIPD());
                // set the Font object to null, as we don't need it any more
                font = null;
            } else {
                log.warn("Cannot update the IPD of an unresolved page number."
                        + " No font information available.");
            }
        }
    }

    
Check if this is resolved.
Returns:
true when this has been resolved/**
     * Check if this is resolved.
     *
     * @return true when this has been resolved
     */
    public boolean isResolved() {
       return resolved;
    }

    
recursively apply the variation factor to all descendant areas
Params:
variationFactor – the variation factor that must be applied to adjustment ratios
lineStretch –     the total stretch of the line
lineShrink –      the total shrink of the line
Returns:
true if there is an UnresolvedArea descendant/**
     * recursively apply the variation factor to all descendant areas
     * @param variationFactor the variation factor that must be applied to adjustment ratios
     * @param lineStretch     the total stretch of the line
     * @param lineShrink      the total shrink of the line
     * @return true if there is an UnresolvedArea descendant
     */
    @Override
    public boolean applyVariationFactor(double variationFactor,
                                        int lineStretch, int lineShrink) {
        return true;
    }

    
Collection bidi inline runs.
Override of @{link InlineParent} implementation.
N.B. [GA] without this override, the page-number-citation_writing_mode_rl
layout engine test will fail. It may be that the test needs to
be updated rather than using this override.
Params:
runs – current list of inline runs
Returns:
modified list of inline runs, having appended new run/**
     * Collection bidi inline runs.
     * Override of @{link InlineParent} implementation.
     *
     * N.B. [GA] without this override, the page-number-citation_writing_mode_rl
     * layout engine test will fail. It may be that the test needs to
     * be updated rather than using this override.
     * @param runs current list of inline runs
     * @return modified list of inline runs, having appended new run
     */
    @Override
    public List collectInlineRuns(List runs) {
        assert runs != null;
        runs.add(new InlineRun(this, new int[] {getBidiLevel()}));
        return runs;
    }
}