3rdPartyLibraries/iTechSharp/iTextSharp/text/factories/RomanNumberFactory.cs

using System;
using System.Text;
/*
 * $Id: RomanNumberFactory.cs,v 1.2 2008/05/13 11:25:14 psoares33 Exp $
 * 
 *
 * Copyright 2007 by Bruno Lowagie.
 *
 * The contents of this file are subject to the Mozilla Public License Version 1.1
 * (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the License.
 *
 * 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.
 *
 * Alternatively, the contents of this file may be used under the terms of the
 * LGPL license (the "GNU LIBRARY GENERAL PUBLIC LICENSE"), in which case the
 * provisions of LGPL are applicable instead of those above.  If you wish to
 * allow use of your version of this file only under the terms of the LGPL
 * License and not to allow others to use your version of this file under
 * the MPL, indicate your decision by deleting the provisions above and
 * replace them with the notice and other provisions required by the LGPL.
 * If you do not delete the provisions above, a recipient may use your version
 * of this file under either the MPL or the GNU LIBRARY GENERAL PUBLIC LICENSE.
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the MPL as stated above or under the terms of the GNU
 * Library General Public License as published by the Free Software Foundation;
 * either version 2 of the License, or 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.
 *
 * 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/
 */
namespace iTextSharp.text.factories {
    /**
    * This class can produce String combinations representing a roman number.
    */
    public class RomanNumberFactory {
        /**
        * Helper class for Roman Digits
        */
        internal class RomanDigit {

            /** part of a roman number */
            public char digit;

            /** value of the roman digit */
            public int value;

            /** can the digit be used as a prefix */
            public bool pre;

            /**
            * Constructs a roman digit
            * @param digit the roman digit
            * @param value the value
            * @param pre can it be used as a prefix
            */
            internal RomanDigit(char digit, int value, bool pre) {
                this.digit = digit;
                this.value = value;
                this.pre = pre;
            }
        }
        
        /**
        * Array with Roman digits.
        */
        private static RomanDigit[] roman = {
            new RomanDigit('m', 1000, false),
            new RomanDigit('d', 500, false),
            new RomanDigit('c', 100, true),
            new RomanDigit('l', 50, false),
            new RomanDigit('x', 10, true),
            new RomanDigit('v', 5, false),
            new RomanDigit('i', 1, true)
        };
        
        /** 
        * Changes an int into a lower case roman number.
        * @param index the original number
        * @return the roman number (lower case)
        */
        public static String GetString(int index) {
            StringBuilder buf = new StringBuilder();

            // lower than 0 ? Add minus
            if (index < 0) {
                buf.Append('-');
                index = -index;
            }

            // greater than 3000
            if (index > 3000) {
                buf.Append('|');
                buf.Append(GetString(index / 1000));
                buf.Append('|');
                // remainder
                index = index - (index / 1000) * 1000;
            }

            // number between 1 and 3000
            int pos = 0;
            while (true) {
                // loop over the array with values for m-d-c-l-x-v-i
                RomanDigit dig = roman[pos];
                // adding as many digits as we can
                while (index >= dig.value) {
                    buf.Append(dig.digit);
                    index -= dig.value;
                }
                // we have the complete number
                if (index <= 0) {
                    break;
                }
                // look for the next digit that can be used in a special way
                int j = pos;
                while (!roman[++j].pre);

                // does the special notation apply?
                if (index + roman[j].value >= dig.value) {
                    buf.Append(roman[j].digit).Append(dig.digit);
                    index -= dig.value - roman[j].value;
                }
                pos++;
            }
            return buf.ToString();
        }
        
        /** 
        * Changes an int into a lower case roman number.
        * @param index the original number
        * @return the roman number (lower case)
        */
        public static String GetLowerCaseString(int index) {
            return GetString(index);        
        }
        
        /** 
        * Changes an int into an upper case roman number.
        * @param index the original number
        * @return the roman number (lower case)
        */
        public static String GetUpperCaseString(int index) {
            return GetString(index).ToUpper(System.Globalization.CultureInfo.InvariantCulture);      
        }

        /** 
        * Changes an int into a roman number.
        * @param index the original number
        * @return the roman number (lower case)
        */
        public static String GetString(int index, bool lowercase) {
            if (lowercase) {
                return GetLowerCaseString(index);
            }
            else {
                return GetUpperCaseString(index);
            }
        }
    }
}