/*
 * $Id: PdfPageLabels.java,v 1.14 2002/07/09 11:28:24 blowagie Exp $
 * $Name:  $
 *
 * Copyright 2001, 2002 Paulo Soares
 *
 *
 * The Original Code is 'iText, a free JAVA-PDF library'.
 *
 * The Initial Developer of the Original Code is Bruno Lowagie. Portions created by
 * the Initial Developer are Copyright (C) 1999, 2000, 2001, 2002 by Bruno Lowagie.
 * All Rights Reserved.
 * Co-Developer of the code is Paulo Soares. Portions created by the Co-Developer
 * are Copyright (C) 2000, 2001, 2002 by Paulo Soares. All Rights Reserved.
 *
 * Contributor(s): all the names of the contributors are added in the source code
 * where applicable.
 *
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 * 
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
 * Boston, MA  02110-1301, USA.
 *
 *
 * If you didn't download this code from the following link, you should check if
 * you aren't using an obsolete version:
 * http://www.lowagie.com/iText/
 */

package com.lowagie.text.pdf;

import java.util.Comparator;
import java.util.TreeMap;
import java.util.Iterator;

/** Page labels are used to identify each
 * page visually on the screen or in print.
 * @author  Paulo Soares (psoares@consiste.pt)
 */
public class PdfPageLabels implements Comparator {

    /** Logical pages will have the form 1,2,3,...
     */    
    public static int DECIMAL_ARABIC_NUMERALS = 0;
    /** Logical pages will have the form I,II,III,IV,...
     */    
    public static int UPPERCASE_ROMAN_NUMERALS = 1;
    /** Logical pages will have the form i,ii,iii,iv,...
     */    
    public static int LOWERCASE_ROMAN_NUMERALS = 2;
    /** Logical pages will have the form of uppercase letters
     * (A to Z for the first 26 pages, AA to ZZ for the next 26, and so on)
     */    
    public static int UPPERCASE_LETTERS = 3;
    /** Logical pages will have the form of uppercase letters
     * (a to z for the first 26 pages, aa to zz for the next 26, and so on)
     */    
    public static int LOWERCASE_LETTERS = 4;
    /** No logical page numbers are generated but fixed text may
     * still exist
     */    
    public static int EMPTY = 5;
    /** Dictionary values to set the logical page styles
     */    
    static PdfName numberingStyle[] = new PdfName[]{PdfName.D, PdfName.R,
                new PdfName("r"), PdfName.A, new PdfName("a")};
    /** The sequence of logical pages. Will contain at least a value for page 1
     */    
    TreeMap map;
    
    /** Creates a new PdfPageLabel with a default logical page 1
     */
    public PdfPageLabels() {
        map = new TreeMap(this);
        addPageLabel(1, DECIMAL_ARABIC_NUMERALS, null, 1);
    }

    /** Compares two <CODE>Integer</CODE>.
     * @param obj the first <CODE>Integer</CODE>
     * @param obj1 the second <CODE>Integer</CODE>
     * @return a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second
     */    
    public int compare(Object obj, Object obj1) {
        int v1 = ((Integer)obj).intValue();
        int v2 = ((Integer)obj1).intValue();
        if (v1 < v2)
            return -1;
        if (v1 == v2)
            return 0;
        return 1;
    }
    
    /** Not used
     * @param obj not used
     * @return always <CODE>true</CODE>
     */    
    public boolean equals(Object obj) {
        return true;
    }
    
    /** Adds or replaces a page label.
     * @param page the real page to start the numbering. First page is 1
     * @param numberStyle the numbering style such as LOWERCASE_ROMAN_NUMERALS
     * @param text the text to prefix the number. Can be <CODE>null</CODE> or empty
     * @param firstPage the first logical page number
     */    
    public void addPageLabel(int page, int numberStyle, String text, int firstPage) {
        if (page < 1 || firstPage < 1)
            throw new IllegalArgumentException("In a page label the page numbers must be greater or equal to 1.");
        PdfName pdfName = null;
        if (numberStyle >= 0 && numberStyle < numberingStyle.length)
            pdfName = numberingStyle[numberStyle];
        Integer iPage = new Integer(page);
        Object obj = new Object[]{iPage, pdfName, text, new Integer(firstPage)};
        map.put(iPage, obj);
    }

    /** Adds or replaces a page label. The first logical page has the default
     * of 1.
     * @param page the real page to start the numbering. First page is 1
     * @param numberStyle the numbering style such as LOWERCASE_ROMAN_NUMERALS
     * @param text the text to prefix the number. Can be <CODE>null</CODE> or empty
     */    
    public void addPageLabel(int page, int numberStyle, String text) {
        addPageLabel(page, numberStyle, text, 1);
    }
    
    /** Adds or replaces a page label. There is no text prefix and the first
     * logical page has the default of 1.
     * @param page the real page to start the numbering. First page is 1
     * @param numberStyle the numbering style such as LOWERCASE_ROMAN_NUMERALS
     */    
    public void addPageLabel(int page, int numberStyle) {
        addPageLabel(page, numberStyle, null, 1);
    }
    
    /** Removes a page label. The first page label can not be removed, only changed.
     * @param page the real page to remove
     */    
    public void removePageLabel(int page) {
        if (page <= 1)
            return;
        map.remove(new Integer(page));
    }

    /** Gets the page label dictionary to insert into the document.
     * @return the page label dictionary
     */    
    PdfDictionary getDictionary() {
        PdfDictionary dic = new PdfDictionary();
        PdfArray array = new PdfArray();
        for (Iterator it = map.values().iterator(); it.hasNext();) {
            Object obj[] = (Object[])it.next();
            PdfDictionary subDic = new PdfDictionary();
            PdfName pName = (PdfName)obj[1];
            if (pName != null)
                subDic.put(PdfName.S, pName);
            String text = (String)obj[2];
            if (text != null)
                subDic.put(PdfName.P, new PdfString(text, PdfObject.TEXT_UNICODE));
            int st = ((Integer)obj[3]).intValue();
            if (st != 1)
                subDic.put(PdfName.ST, new PdfNumber(st));
            array.add(new PdfNumber(((Integer)obj[0]).intValue() - 1));
            array.add(subDic);
        }
        dic.put(PdfName.NUMS, array);
        return dic;
    }
}
