/*
 * 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.
 */

// Sep 14, 2000:
//  Fixed problem with namespace handling. Contributed by
//  David Blondeau <blondeau@intalio.com>
// Sep 14, 2000:
//  Fixed serializer to report IO exception directly, instead at
//  the end of document processing.
//  Reported by Patrick Higgins <phiggins@transzap.com>
// Aug 21, 2000:
//  Fixed bug in startDocument not calling prepare.
//  Reported by Mikael Staldal <d96-mst-ingen-reklam@d.kth.se>
// Aug 21, 2000:
//  Added ability to omit DOCTYPE declaration.

package org.apache.xml.serialize;

import java.io.IOException;
import java.io.OutputStream;
import java.io.Writer;

import org.apache.xerces.dom.DOMMessageFormatter;
import org.apache.xerces.util.NamespaceSupport;
import org.apache.xerces.util.SymbolTable;
import org.apache.xerces.util.XML11Char;
import org.apache.xerces.util.XMLChar;
import org.w3c.dom.DOMError;
import org.w3c.dom.Document;
import org.xml.sax.SAXException;

/**
 * Implements an XML serializer supporting both DOM and SAX pretty
 * serializing. For usage instructions see {@link Serializer}.
 * <p>
 * If an output stream is used, the encoding is taken from the
 * output format (defaults to <tt>UTF-8</tt>). If a writer is
 * used, make sure the writer uses the same encoding (if applies)
 * as specified in the output format.
 * <p>
 * The serializer supports both DOM and SAX. SAX serializing is done by firing
 * SAX events and using the serializer as a document handler. DOM serializing is done
 * by calling {@link #serialize(Document)} or by using DOM Level 3  
 * {@link org.w3c.dom.ls.LSSerializer} and
 * serializing with {@link org.w3c.dom.ls.LSSerializer#write},
 * {@link org.w3c.dom.ls.LSSerializer#writeToString}.
 * <p>
 * If an I/O exception occurs while serializing, the serializer
 * will not throw an exception directly, but only throw it
 * at the end of serializing (either DOM or SAX's {@link
 * org.xml.sax.DocumentHandler#endDocument}.
 * <p>
 * For elements that are not specified as whitespace preserving,
 * the serializer will potentially break long text lines at space
 * boundaries, indent lines, and serialize elements on separate
 * lines. Line terminators will be regarded as spaces, and
 * spaces at beginning of line will be stripped.
 * 
 * @deprecated This class was deprecated in Xerces 2.9.0. It is recommended 
 * that new applications use the DOM Level 3 LSSerializer or JAXP's Transformation 
 * API for XML (TrAX) for serializing XML. See the Xerces documentation for more 
 * information.
 * @author <a href="mailto:arkin@intalio.com">Assaf Arkin</a>
 * @author <a href="mailto:rahul.srivastava@sun.com">Rahul Srivastava</a>
 * @author Elena Litani IBM
 * @version $Revision$ $Date$
 * @see Serializer
 */
public class XML11Serializer 
extends XMLSerializer {

    //
    // constants
    //

    protected static final boolean DEBUG = false;

    // 
    // data
    //

    // 
    // DOM Level 3 implementation: variables intialized in DOMSerializerImpl
    // 

    /** stores namespaces in scope */
    protected NamespaceSupport fNSBinder;

    /** stores all namespace bindings on the current element */
    protected NamespaceSupport fLocalNSBinder;

    /** symbol table for serialization */
    protected SymbolTable fSymbolTable;    

    // is node dom level 1 node?
    protected boolean fDOML1 = false;
    // counter for new prefix names
    protected int fNamespaceCounter = 1;
    protected final static String PREFIX = "NS";

    /**
     * Controls whether namespace fixup should be performed during
     * the serialization. 
     * NOTE: if this field is set to true the following 
     * fields need to be initialized: fNSBinder, fLocalNSBinder, fSymbolTable, 
     * XMLSymbols.EMPTY_STRING, fXmlSymbol, fXmlnsSymbol, fNamespaceCounter.
     */
    protected boolean fNamespaces = false;

    /**
     * Constructs a new serializer. The serializer cannot be used without
     * calling {@link #setOutputCharStream} or {@link #setOutputByteStream}
     * first.
     */
    public XML11Serializer() {
        super( );
        _format.setVersion("1.1");
    }


    /**
     * Constructs a new serializer. The serializer cannot be used without
     * calling {@link #setOutputCharStream} or {@link #setOutputByteStream}
     * first.
     */
    public XML11Serializer( OutputFormat format ) {
        super( format );
        _format.setVersion("1.1");
    }


    /**
     * Constructs a new serializer that writes to the specified writer
     * using the specified output format. If <tt>format</tt> is null,
     * will use a default output format.
     *
     * @param writer The writer to use
     * @param format The output format to use, null for the default
     */
    public XML11Serializer( Writer writer, OutputFormat format ) {
        super( writer, format );
        _format.setVersion("1.1");
    }


    /**
     * Constructs a new serializer that writes to the specified output
     * stream using the specified output format. If <tt>format</tt>
     * is null, will use a default output format.
     *
     * @param output The output stream to use
     * @param format The output format to use, null for the default
     */
    public XML11Serializer( OutputStream output, OutputFormat format ) {
        super( output, format != null ? format : new OutputFormat( Method.XML, null, false ) );
        _format.setVersion("1.1");
    }

    //-----------------------------------------//
    // SAX content handler serializing methods //
    //-----------------------------------------//


    public void characters( char[] chars, int start, int length )
        throws SAXException
    {
        ElementState state;

        try {
            state = content();

            // Check if text should be print as CDATA section or unescaped
            // based on elements listed in the output format (the element
            // state) or whether we are inside a CDATA section or entity.

            if ( state.inCData || state.doCData ) {
                int          saveIndent;

                // Print a CDATA section. The text is not escaped, but ']]>'
                // appearing in the code must be identified and dealt with.
                // The contents of a text node is considered space preserving.
                if ( ! state.inCData ) {
                    _printer.printText( "<![CDATA[" );
                    state.inCData = true;
                }
                saveIndent = _printer.getNextIndent();
                _printer.setNextIndent( 0 );
                char ch;
                final int end = start + length;
                for ( int index = start; index < end; ++index ) {
                    ch = chars[index];
                    if ( ch == ']' && index + 2 < end &&
                        chars[ index + 1 ] == ']' && chars[ index + 2 ] == '>' ) {
                        _printer.printText("]]]]><![CDATA[>");
                        index +=2; 
                        continue;
                    }
                    if (!XML11Char.isXML11Valid(ch)) {
                        // check if it is surrogate
                        if (++index < end) {
                            surrogates(ch, chars[index], true);
                        } 
                        else {
                            fatalError("The character '"+ch+"' is an invalid XML character"); 
                        }
                        continue;
                    }
                    if ( _encodingInfo.isPrintable(ch) && XML11Char.isXML11ValidLiteral(ch)) {
                        _printer.printText(ch);
                    } 
                    else {
                        // The character is not printable -- split CDATA section
                        _printer.printText("]]>&#x");                        
                        _printer.printText(Integer.toHexString(ch));                        
                        _printer.printText(";<![CDATA[");
                    }
                }
                _printer.setNextIndent( saveIndent );

            } 
            else {

                int saveIndent;

                if ( state.preserveSpace ) {
                    // If preserving space then hold of indentation so no
                    // excessive spaces are printed at line breaks, escape
                    // the text content without replacing spaces and print
                    // the text breaking only at line breaks.
                    saveIndent = _printer.getNextIndent();
                    _printer.setNextIndent( 0 );
                    printText( chars, start, length, true, state.unescaped );
                    _printer.setNextIndent( saveIndent );
                } 
                else {
                    printText( chars, start, length, false, state.unescaped );
                }
            }
        } 
        catch ( IOException except ) {
            throw new SAXException( except );
        }
    }

    //
    // overwrite printing functions to make sure serializer prints out valid XML
    //
    protected void printEscaped( String source ) throws IOException {
        int length = source.length();
        for ( int i = 0 ; i < length ; ++i ) {
            int ch = source.charAt(i);
            if (!XML11Char.isXML11Valid(ch)) {
                if (++i <length) {
                    surrogates(ch, source.charAt(i), false);
                } 
                else {
                    fatalError("The character '"+(char)ch+"' is an invalid XML character"); 
                }
                continue;
            }
            if (ch == '\n' || ch == '\r' || ch == '\t' || ch == 0x0085 || ch == 0x2028) {
                printHex(ch);
            } 
            else if (ch == '<') {
                _printer.printText("&lt;");
            } 
            else if (ch == '&') {
                _printer.printText("&amp;");
            } 
            else if (ch == '"') {
                _printer.printText("&quot;");
            } 
            else if ((ch >= ' ' && _encodingInfo.isPrintable((char) ch))) {
                _printer.printText((char) ch);
            } 
            else {
                printHex(ch);
            }
        }
    }

    protected final void printCDATAText(String text) throws IOException {
        int length = text.length();
        char ch;

        for (int index = 0; index < length; ++index) {
            ch = text.charAt(index);

            if (ch == ']'
                && index + 2 < length
                && text.charAt(index + 1) == ']'
                && text.charAt(index + 2) == '>') { // check for ']]>'
                if (fDOMErrorHandler != null){
                    // REVISIT: this means that if DOM Error handler is not registered we don't report any
                    // fatal errors and might serialize not wellformed document
                if ((features & DOMSerializerImpl.SPLITCDATA) == 0
                    && (features & DOMSerializerImpl.WELLFORMED) == 0) {
                    // issue fatal error
                    String msg =
                        DOMMessageFormatter.formatMessage(
                            DOMMessageFormatter.SERIALIZER_DOMAIN,
                            "EndingCDATA",
                            null);
                    modifyDOMError(
                        msg,
                        DOMError.SEVERITY_FATAL_ERROR,
                        null, fCurrentNode);
                    boolean continueProcess =
                        fDOMErrorHandler.handleError(fDOMError);
                    if (!continueProcess) {
                        throw new IOException();
                    }
                } else {
                    // issue warning
                    String msg =
                        DOMMessageFormatter.formatMessage(
                            DOMMessageFormatter.SERIALIZER_DOMAIN,
                            "SplittingCDATA",
                            null);
                    modifyDOMError(
                        msg,
                        DOMError.SEVERITY_WARNING,
                        null, fCurrentNode);
                    fDOMErrorHandler.handleError(fDOMError);
                }
                }
                // split CDATA section
                _printer.printText("]]]]><![CDATA[>");
                index += 2;
                continue;
            }

            if (!XML11Char.isXML11Valid(ch)) {
                // check if it is surrogate
                if (++index < length) {
                    surrogates(ch, text.charAt(index), true);
                } 
                else {
                    fatalError("The character '" + ch + "' is an invalid XML character");
                }
                continue;
            }
            if (_encodingInfo.isPrintable(ch)
                && XML11Char.isXML11ValidLiteral(ch)) {
                _printer.printText(ch);
            } 
            else {
                // The character is not printable -- split CDATA section
                _printer.printText("]]>&#x");
                _printer.printText(Integer.toHexString(ch));
                _printer.printText(";<![CDATA[");
            }
        }
    }

    // note that this "int" should, in all cases, be a char.
    // REVISIT:  make it a char...
    protected final void printXMLChar( int ch ) throws IOException {
        if (ch == '\r' || ch == 0x0085 || ch == 0x2028) {
            printHex(ch);
        } 
        else if ( ch == '<') {
            _printer.printText("&lt;");
        } 
        else if (ch == '&') {
            _printer.printText("&amp;");
        } 
        else if (ch == '>'){
            // character sequence "]]>" can't appear in content, therefore
            // we should escape '>' 
            _printer.printText("&gt;");
        } 
        else if ( _encodingInfo.isPrintable((char)ch) && XML11Char.isXML11ValidLiteral(ch)) { 
            _printer.printText((char)ch);
        } 
        else {
            printHex(ch);
        }
    }

    protected final void surrogates(int high, int low, boolean inContent) throws IOException{
        if (XMLChar.isHighSurrogate(high)) {
            if (!XMLChar.isLowSurrogate(low)) {
                //Invalid XML
                fatalError("The character '"+(char)low+"' is an invalid XML character"); 
            }
            else {
                int supplemental = XMLChar.supplemental((char)high, (char)low);
                if (!XML11Char.isXML11Valid(supplemental)) {
                    //Invalid XML
                    fatalError("The character '"+(char)supplemental+"' is an invalid XML character"); 
                }
                else {
                    if (inContent && content().inCData) {
                        _printer.printText("]]>&#x");                        
                        _printer.printText(Integer.toHexString(supplemental));                        
                        _printer.printText(";<![CDATA[");
                    }  
                    else {
						printHex(supplemental);
                    }
                }
            }
        } 
        else {
            fatalError("The character '"+(char)high+"' is an invalid XML character"); 
        }

    }

    protected void printText( String text, boolean preserveSpace, boolean unescaped )
    throws IOException {
        int index;
        char ch;
        int length = text.length();
        if ( preserveSpace ) {
            // Preserving spaces: the text must print exactly as it is,
            // without breaking when spaces appear in the text and without
            // consolidating spaces. If a line terminator is used, a line
            // break will occur.
            for ( index = 0 ; index < length ; ++index ) {
                ch = text.charAt( index );
                if (!XML11Char.isXML11Valid(ch)) {
                    // check if it is surrogate
                    if (++index <length) {
                        surrogates(ch, text.charAt(index), true);
                    } else {
                        fatalError("The character '"+ch+"' is an invalid XML character"); 
                    }
                    continue;
                }
                if ( unescaped  && XML11Char.isXML11ValidLiteral(ch)) {
                    _printer.printText( ch );
                } 
                else {
                    printXMLChar( ch );
                }
            }
        } 
        else {
            // Not preserving spaces: print one part at a time, and
            // use spaces between parts to break them into different
            // lines. Spaces at beginning of line will be stripped
            // by printing mechanism. Line terminator is treated
            // no different than other text part.
            for ( index = 0 ; index < length ; ++index ) {
                ch = text.charAt( index );
                if (!XML11Char.isXML11Valid(ch)) {
                    // check if it is surrogate
                    if (++index <length) {
                        surrogates(ch, text.charAt(index), true);
                    } else {
                        fatalError("The character '"+ch+"' is an invalid XML character"); 
                    }
                    continue;
                }
                if ( unescaped && XML11Char.isXML11ValidLiteral(ch) ) {
                    _printer.printText( ch );
                }
                else {
                    printXMLChar( ch );
                }
            }
        }
    }

    protected void printText( char[] chars, int start, int length,
                              boolean preserveSpace, boolean unescaped ) throws IOException {

        if ( preserveSpace ) {
            // Preserving spaces: the text must print exactly as it is,
            // without breaking when spaces appear in the text and without
            // consolidating spaces. If a line terminator is used, a line
            // break will occur.
            while ( length-- > 0 ) {
                char ch = chars[start++];
                if (!XML11Char.isXML11Valid(ch)) {
                    // check if it is surrogate
                    if ( length-- > 0) {
                        surrogates(ch, chars[start++], true);
                    } else {
                        fatalError("The character '"+ch+"' is an invalid XML character"); 
                    }
                    continue;
                }
                if ( unescaped && XML11Char.isXML11ValidLiteral(ch)) {
                    _printer.printText( ch );
                } 
                else {
                    printXMLChar( ch );
                }
            }
        } 
        else {
            // Not preserving spaces: print one part at a time, and
            // use spaces between parts to break them into different
            // lines. Spaces at beginning of line will be stripped
            // by printing mechanism. Line terminator is treated
            // no different than other text part.
            while ( length-- > 0 ) {
                char ch = chars[start++];
                if (!XML11Char.isXML11Valid(ch)) {
                    // check if it is surrogate
                    if ( length-- > 0) {
                        surrogates(ch, chars[start++], true);
                    } else {
                        fatalError("The character '"+ch+"' is an invalid XML character"); 
                    }
                    continue;
                }
                if ( unescaped && XML11Char.isXML11ValidLiteral(ch)) {
                    _printer.printText( ch );
                }
                else {
                    printXMLChar( ch );
                }
            }
        }
    }

    public boolean reset() {
        super.reset();
        return true;
    }

}