using System;
using System.Text;
using System.Drawing;

using iTextSharp.text;

/*
 * $Id: HtmlEncoder.cs,v 1.6 2008/05/13 11:25:15 psoares33 Exp $
 * 
 *
 * Copyright 1999, 2000, 2001, 2002 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.html {
    /**
     * This class converts a <CODE>String</CODE> to the HTML-format of a String.
     * <P>
     * To convert the <CODE>String</CODE>, each character is examined:
     * <UL>
     * <LI>ASCII-characters from 000 till 031 are represented as &amp;#xxx;<BR>
     *     (with xxx = the value of the character)
     * <LI>ASCII-characters from 032 t/m 127 are represented by the character itself, except for:
     *     <UL>
     *     <LI>'\n' becomes &lt;BR&gt;\n
     *     <LI>&quot; becomes &amp;quot;
     *     <LI>&amp; becomes &amp;amp;
     *     <LI>&lt; becomes &amp;lt;
     *     <LI>&gt; becomes &amp;gt;
     *     </UL>
     * <LI>ASCII-characters from 128 till 255 are represented as &amp;#xxx;<BR>
     *     (with xxx = the value of the character)
     * </UL>
     * <P>
     * Example:
     * <P><BLOCKQUOTE><PRE>
     *    String htmlPresentation = HtmlEncoder.Encode("Marie-Th&#233;r&#232;se S&#248;rensen");
     * </PRE></BLOCKQUOTE><P>
     * for more info: see O'Reilly; "HTML: The Definitive Guide" (page 164)
     *
     * @author  mario.maccarini@rug.ac.be
     */

    public sealed class HtmlEncoder {
    
        // membervariables
    
        /** List with the HTML translation of all the characters. */
        private static String[] htmlCode = new String[256];
    
        static HtmlEncoder() {
            for (int i = 0; i < 10; i++) {
                htmlCode[i] = "&#00" + i + ";";
            }
        
            for (int i = 10; i < 32; i++) {
                htmlCode[i] = "&#0" + i + ";";
            }
        
            for (int i = 32; i < 128; i++) {
                htmlCode[i] = ((char)i).ToString();
            }
        
            // Special characters
            htmlCode['\t'] = "\t";
            htmlCode['\n'] = "<" + HtmlTags.NEWLINE + " />\n";
            htmlCode['\"'] = "&quot;"; // double quote
            htmlCode['&'] = "&amp;"; // ampersand
            htmlCode['<'] = "&lt;"; // lower than
            htmlCode['>'] = "&gt;"; // greater than
        
            for (int i = 128; i < 256; i++) {
                htmlCode[i] = "&#" + i + ";";
            }
        }
    
    
        // constructors
    
        /**
         * This class will never be constructed.
         * <P>
         * HtmlEncoder only contains static methods.
         */
    
        private HtmlEncoder () { }
    
        // methods
    
        /**
         * Converts a <CODE>String</CODE> to the HTML-format of this <CODE>String</CODE>.
         *
         * @param   string  The <CODE>String</CODE> to convert
         * @return  a <CODE>String</CODE>
         */
    
        public static String Encode(String str) {
            int n = str.Length;
            char character;
            StringBuilder buffer = new StringBuilder();
            // loop over all the characters of the String.
            for (int i = 0; i < n; i++) {
                character = str[i];
                // the Htmlcode of these characters are added to a StringBuilder one by one
                if (character < 256) {
                    buffer.Append(htmlCode[character]);
                }
                else {
                    // Improvement posted by Joachim Eyrich
                    buffer.Append("&#").Append((int)character).Append(';');
                }
            }
            return buffer.ToString();
        }
    
        /**
         * Converts a <CODE>Color</CODE> into a HTML representation of this <CODE>Color</CODE>.
         *
         * @param   color   the <CODE>Color</CODE> that has to be converted.
         * @return  the HTML representation of this <COLOR>Color</COLOR>
         */
    
        public static String Encode(Color color) {
            StringBuilder buffer = new StringBuilder("#");
            if (color.R < 16) {
                buffer.Append('0');
            }
            buffer.Append(System.Convert.ToString(color.R, 16));
            if (color.G < 16) {
                buffer.Append('0');
            }
            buffer.Append(System.Convert.ToString(color.G, 16));
            if (color.B < 16) {
                buffer.Append('0');
            }
            buffer.Append(System.Convert.ToString(color.B, 16));
            return buffer.ToString();
        }
    
        /**
         * Translates the alignment value.
         *
         * @param   alignment   the alignment value
         * @return  the translated value
         */
    
        public static String GetAlignment(int alignment) {
            switch (alignment) {
                case Element.ALIGN_LEFT:
                    return HtmlTags.ALIGN_LEFT;
                case Element.ALIGN_CENTER:
                    return HtmlTags.ALIGN_CENTER;
                case Element.ALIGN_RIGHT:
                    return HtmlTags.ALIGN_RIGHT;
                case Element.ALIGN_JUSTIFIED:
                case Element.ALIGN_JUSTIFIED_ALL:
                    return HtmlTags.ALIGN_JUSTIFIED;
                case Element.ALIGN_TOP:
                    return HtmlTags.ALIGN_TOP;
                case Element.ALIGN_MIDDLE:
                    return HtmlTags.ALIGN_MIDDLE;
                case Element.ALIGN_BOTTOM:
                    return HtmlTags.ALIGN_BOTTOM;
                case Element.ALIGN_BASELINE:
                    return HtmlTags.ALIGN_BASELINE;
                default:
                    return "";
            }
        }
    }
}