using System;
using System.IO;
using System.Collections;
using System.util;
using iTextSharp.text.pdf;
/*
 * $Id: DocWriter.cs,v 1.7 2008/05/13 11:25:09 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 {
    /// <summary>
    /// An abstract Writer class for documents.
    /// </summary>
    /// <remarks>
    /// DocWriter is the abstract class of several writers such
    /// as PdfWriter and HtmlWriter.
    /// A DocWriter can be added as a DocListener
    /// to a certain Document by getting an instance (see method
    /// GetInstance() in the specific writer-classes).
    /// Every Element added to the original Document
    /// will be written to the stream of the listening
    /// DocWriter.
    /// </remarks>
    /// <seealso cref="T:iTextSharp.text.Document"/>
    /// <seealso cref="T:iTextSharp.text.IDocListener"/>
    public abstract class DocWriter : IDocListener {

        /// <summary> This is some byte that is often used. </summary>
        public const byte NEWLINE = (byte)'\n';

        /// <summary> This is some byte that is often used. </summary>
        public const byte TAB = (byte)'\t';

        /// <summary> This is some byte that is often used. </summary>
        public const byte LT = (byte)'<';

        /// <summary> This is some byte that is often used. </summary>
        public const byte SPACE = (byte)' ';

        /// <summary> This is some byte that is often used. </summary>
        public const byte EQUALS = (byte)'=';

        /// <summary> This is some byte that is often used. </summary>
        public const byte QUOTE = (byte)'\"';

        /// <summary> This is some byte that is often used. </summary>
        public const byte GT = (byte)'>';

        /// <summary> This is some byte that is often used. </summary>
        public const byte FORWARD = (byte)'/';

        // membervariables

        /// <summary> The pageSize. </summary>
        protected Rectangle pageSize;

        /// <summary> This is the document that has to be written. </summary>
        protected Document document;

        /// <summary> The stream of this writer. </summary>
        protected OutputStreamCounter os;

        /// <summary> Is the writer open for writing? </summary>
        protected bool open = false;

        /// <summary> Do we have to pause all writing actions? </summary>
        protected bool pause = false;

        /** Closes the stream on document close */
        protected bool closeStream = true;

        // constructor
    
        protected DocWriter() {
        }
        /// <summary>
        /// Constructs a DocWriter.
        /// </summary>
        /// <param name="document">The Document that has to be written</param>
        /// <param name="os">The Stream the writer has to write to.</param>
        protected DocWriter(Document document, Stream os)  
        {
            this.document = document;
            this.os = new OutputStreamCounter(os);
        }

        // implementation of the DocListener methods

        /// <summary>
        /// Signals that an Element was added to the Document.
        /// </summary>
        /// <remarks>
        /// This method should be overriden in the specific DocWriter classes
        /// derived from this abstract class.
        /// </remarks>
        /// <param name="element"></param>
        /// <returns>false</returns>
        public virtual bool Add(IElement element) {
            return false;
        }

        /// <summary>
        /// Signals that the Document was opened.
        /// </summary>
        public virtual void Open() {
            open = true;
        }

        /// <summary>
        /// Sets the pagesize.
        /// </summary>
        /// <param name="pageSize">the new pagesize</param>
        /// <returns>a boolean</returns>
        public virtual bool SetPageSize(Rectangle pageSize) {
            this.pageSize = pageSize;
            return true;
        }

        /// <summary>
        /// Sets the margins.
        /// </summary>
        /// <remarks>
        /// This does nothing. Has to be overridden if needed.
        /// </remarks>
        /// <param name="marginLeft">the margin on the left</param>
        /// <param name="marginRight">the margin on the right</param>
        /// <param name="marginTop">the margin on the top</param>
        /// <param name="marginBottom">the margin on the bottom</param>
        /// <returns></returns>
        public virtual bool SetMargins(float marginLeft, float marginRight, float marginTop, float marginBottom) {
            return false;
        }

        /// <summary>
        /// Signals that an new page has to be started.
        /// </summary>
        /// <remarks>
        /// This does nothing. Has to be overridden if needed.
        /// </remarks>
        /// <returns>true if the page was added, false if not.</returns>
        public virtual bool NewPage() {
            if (!open) {
                return false;
            }
            return true;
        }

        /// <summary>
        /// Changes the header of this document.
        /// </summary>
        /// <remarks>
        /// This method should be overriden in the specific DocWriter classes
        /// derived from this abstract class if they actually support the use of
        /// headers.
        /// </remarks>
        /// <value>the new header</value>
        public virtual HeaderFooter Header {
            set {}
        }

        /// <summary>
        /// Resets the header of this document.
        /// </summary>
        /// <remarks>
        /// This method should be overriden in the specific DocWriter classes
        /// derived from this abstract class if they actually support the use of
        /// headers.
        /// </remarks>
        public virtual void ResetHeader() {
        }

        /// <summary>
        /// Changes the footer of this document.
        /// </summary>
        /// <remarks>
        /// This method should be overriden in the specific DocWriter classes
        /// derived from this abstract class if they actually support the use of
        /// footers.
        /// </remarks>
        /// <value>the new footer</value>
        public virtual HeaderFooter Footer {
            set {}
        }

        /// <summary>
        /// Resets the footer of this document.
        /// </summary>
        /// <remarks>
        /// This method should be overriden in the specific DocWriter classes
        /// derived from this abstract class if they actually support the use of
        /// footers.
        /// </remarks>
        public virtual void ResetFooter() {
        }

        /// <summary>
        /// Sets the page number to 0.
        /// </summary>
        /// <remarks>
        /// This method should be overriden in the specific DocWriter classes
        /// derived from this abstract class if they actually support the use of
        /// pagenumbers.
        /// </remarks>
        public virtual void ResetPageCount() {
        }

        /// <summary>
        /// Sets the page number.
        /// </summary>
        /// <remarks>
        /// This method should be overriden in the specific DocWriter classes
        /// derived from this abstract class if they actually support the use of
        /// pagenumbers.
        /// </remarks>
        public virtual int PageCount {
            set {}
        }

        /// <summary>
        /// Signals that the Document was closed and that no other
        /// Elements will be added.
        /// </summary>
        public virtual void Close() {
            open = false;
            os.Flush();
            if (closeStream)
                os.Close();
        }

        // methods

        /// <summary>
        /// Converts a string into a Byte array
        /// according to the ISO-8859-1 codepage.
        /// </summary>
        /// <param name="text">the text to be converted</param>
        /// <returns>the conversion result</returns>
        public static byte[] GetISOBytes(string text) {
            if (text == null)
                return null;
            int len = text.Length;
            byte[] b = new byte[len];
            for (int k = 0; k < len; ++k)
                b[k] = (byte)text[k];
            return b;
        }

        /// <summary>
        /// Let the writer know that all writing has to be paused.
        /// </summary>
        public virtual void Pause() {
            pause = true;
        }

        /**
        * Checks if writing is paused.
        *
        * @return       <CODE>true</CODE> if writing temporarely has to be paused, <CODE>false</CODE> otherwise.
        */
        
        public bool IsPaused() {
            return pause;
        }

        /// <summary>
        /// Let the writer know that writing may be resumed.
        /// </summary>
        public virtual void Resume() {
            pause = false;
        }

        /// <summary>
        /// Flushes the Stream.
        /// </summary>
        public virtual void Flush() {
            os.Flush();
        }

        /// <summary>
        /// Writes a string to the stream.
        /// </summary>
        /// <param name="str">the string to write</param>
        protected void Write(string str) {
            byte[] tmp = GetISOBytes(str);
            os.Write(tmp, 0, tmp.Length);
        }

        /// <summary>
        /// Writes a number of tabs.
        /// </summary>
        /// <param name="indent">the number of tabs to add</param>
        protected void AddTabs(int indent) {
            os.WriteByte(NEWLINE);
            for (int i = 0; i < indent; i++) {
                os.WriteByte(TAB);
            }
        }

        /// <summary>
        /// Writes a key-value pair to the stream.
        /// </summary>
        /// <param name="key">the name of an attribute</param>
        /// <param name="value">the value of an attribute</param>
        protected void Write(string key, string value) {
            os.WriteByte(SPACE);
            Write(key);
            os.WriteByte(EQUALS);
            os.WriteByte(QUOTE);
            Write(value);
            os.WriteByte(QUOTE);
        }

        /// <summary>
        /// Writes a starttag to the stream.
        /// </summary>
        /// <param name="tag">the name of the tag</param>
        protected void WriteStart(string tag) {
            os.WriteByte(LT);
            Write(tag);
        }

        /// <summary>
        /// Writes an endtag to the stream.
        /// </summary>
        /// <param name="tag">the name of the tag</param>
        protected void WriteEnd(string tag) {
            os.WriteByte(LT);
            os.WriteByte(FORWARD);
            Write(tag);
            os.WriteByte(GT);
        }

        /// <summary>
        /// Writes an endtag to the stream.
        /// </summary>
        protected void WriteEnd() {
            os.WriteByte(SPACE);
            os.WriteByte(FORWARD);
            os.WriteByte(GT);
        }

        /// <summary>
        /// Writes the markup attributes of the specified MarkupAttributes
        /// object to the stream.
        /// </summary>
        /// <param name="mAtt">the MarkupAttributes to write.</param>
        /// <returns></returns>
        protected bool WriteMarkupAttributes(Properties markup) {
            if (markup == null) return false;
            foreach (String name in markup.Keys) {
                Write(name, markup[name]);
            }
            markup.Clear();
            return true;
        }

        public virtual bool CloseStream {
            get {
                return closeStream;
            }
            set {
                closeStream = value;
            }
        }

        public virtual bool SetMarginMirroring(bool marginMirroring) {
            return false;
        }
    }
}