/*
 * 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.
 */

package org.apache.xerces.impl;

import java.io.IOException;

import org.apache.xerces.util.SymbolTable;
import org.apache.xerces.util.XML11Char;
import org.apache.xerces.util.XMLChar;
import org.apache.xerces.util.XMLStringBuffer;
import org.apache.xerces.xni.XMLString;
import org.apache.xerces.xni.XNIException;

This class is responsible for scanning the declarations found
in the internal and external subsets of a DTD in an XML document.
The scanner acts as the sources for the DTD information which is 
communicated to the DTD handlers.

This component requires the following features and properties from the
component manager that uses it:

 
http://xml.org/sax/features/validation
 
http://apache.org/xml/features/scanner/notify-char-refs
 
http://apache.org/xml/properties/internal/symbol-table
 
http://apache.org/xml/properties/internal/error-reporter
 
http://apache.org/xml/properties/internal/entity-manager

Author:
Arnaud  Le Hors, IBM, Andy Clark, IBM, Glenn Marcy, IBM, Eric Ye, IBM
@xerces.internal
Version:
$Id: XML11DTDScannerImpl.java 572055 2007-09-02 17:55:43Z mrglavas $/**
 * This class is responsible for scanning the declarations found
 * in the internal and external subsets of a DTD in an XML document.
 * The scanner acts as the sources for the DTD information which is 
 * communicated to the DTD handlers.
 * <p>
 * This component requires the following features and properties from the
 * component manager that uses it:
 * <ul>
 *  <li>http://xml.org/sax/features/validation</li>
 *  <li>http://apache.org/xml/features/scanner/notify-char-refs</li>
 *  <li>http://apache.org/xml/properties/internal/symbol-table</li>
 *  <li>http://apache.org/xml/properties/internal/error-reporter</li>
 *  <li>http://apache.org/xml/properties/internal/entity-manager</li>
 * </ul>
 * 
 * @xerces.internal

 *
 * @author Arnaud  Le Hors, IBM
 * @author Andy Clark, IBM
 * @author Glenn Marcy, IBM
 * @author Eric Ye, IBM
 *
 * @version $Id: XML11DTDScannerImpl.java 572055 2007-09-02 17:55:43Z mrglavas $
 */
public class XML11DTDScannerImpl
    extends XMLDTDScannerImpl {

    
String buffer. /** String buffer. */
    private final XMLStringBuffer fStringBuffer = new XMLStringBuffer();
    
    //
    // Constructors
    //

    
Default constructor. /** Default constructor. */
    public XML11DTDScannerImpl() {super();} // <init>()

    
Constructor for he use of non-XMLComponentManagers. /** Constructor for he use of non-XMLComponentManagers. */
    public XML11DTDScannerImpl(SymbolTable symbolTable,
                XMLErrorReporter errorReporter, XMLEntityManager entityManager) {
        super(symbolTable, errorReporter, entityManager);
    }

    //
    // XMLDTDScanner methods
    //

    //
    // XMLScanner methods
    //
    // NOTE:  this is a carbon copy of the code in XML11DocumentScannerImpl;
    // we need to override these methods in both places.  Ah for
    // multiple inheritance...
    // This needs to be refactored!!!  - NG
    
Scans public ID literal.
[12] PubidLiteral ::= '"' PubidChar* '"' | "'" (PubidChar - "'")* "'" 
[13] PubidChar::= #x20 | #xD | #xA | [a-zA-Z0-9] | [-'()+,./:=?;!*#@$_%]
The returned string is normalized according to the following rule,
from http://www.w3.org/TR/REC-xml#dt-pubid:
Before a match is attempted, all strings of white space in the public
identifier must be normalized to single space characters (#x20), and
leading and trailing white space must be removed.
Params:
literal – The string to fill in with the public ID literal.
Returns:
True on success.
Note: This method uses fStringBuffer, anything in it at
the time of calling is lost./**
     * Scans public ID literal.
     *
     * [12] PubidLiteral ::= '"' PubidChar* '"' | "'" (PubidChar - "'")* "'" 
     * [13] PubidChar::= #x20 | #xD | #xA | [a-zA-Z0-9] | [-'()+,./:=?;!*#@$_%]
     *
     * The returned string is normalized according to the following rule,
     * from http://www.w3.org/TR/REC-xml#dt-pubid:
     *
     * Before a match is attempted, all strings of white space in the public
     * identifier must be normalized to single space characters (#x20), and
     * leading and trailing white space must be removed.
     *
     * @param literal The string to fill in with the public ID literal.
     * @return True on success.
     *
     * <strong>Note:</strong> This method uses fStringBuffer, anything in it at
     * the time of calling is lost.
     */
    protected boolean scanPubidLiteral(XMLString literal)
        throws IOException, XNIException
    {
        int quote = fEntityScanner.scanChar();
        if (quote != '\'' && quote != '"') {
            reportFatalError("QuoteRequiredInPublicID", null);
            return false;
        }

        fStringBuffer.clear();
        // skip leading whitespace
        boolean skipSpace = true;
        boolean dataok = true;
        while (true) {
            int c = fEntityScanner.scanChar();
            // REVISIT:  it could really only be \n or 0x20; all else is normalized, no?  - neilg
            if (c == ' ' || c == '\n' || c == '\r' || c == 0x85 || c == 0x2028) {
                if (!skipSpace) {
                    // take the first whitespace as a space and skip the others
                    fStringBuffer.append(' ');
                    skipSpace = true;
                }
            }
            else if (c == quote) {
                if (skipSpace) {
                    // if we finished on a space let's trim it
                    fStringBuffer.length--;
                }
                literal.setValues(fStringBuffer);
                break;
            }
            else if (XMLChar.isPubid(c)) {
                fStringBuffer.append((char)c);
                skipSpace = false;
            }
            else if (c == -1) {
                reportFatalError("PublicIDUnterminated", null);
                return false;
            }
            else {
                dataok = false;
                reportFatalError("InvalidCharInPublicID",
                                 new Object[]{Integer.toHexString(c)});
            }
        }
        return dataok;
   }
   
    
Normalize whitespace in an XMLString converting all whitespace
characters to space characters.
/**
     * Normalize whitespace in an XMLString converting all whitespace
     * characters to space characters.
     */
    protected void normalizeWhitespace(XMLString value) {
        int end = value.offset + value.length;
        for (int i = value.offset; i < end; ++i) {
            int c = value.ch[i];
            if (XMLChar.isSpace(c)) {
                value.ch[i] = ' ';
            }
        }
    }
    
    
Normalize whitespace in an XMLString converting all whitespace
characters to space characters.
/**
     * Normalize whitespace in an XMLString converting all whitespace
     * characters to space characters.
     */
    protected void normalizeWhitespace(XMLString value, int fromIndex) {
        int end = value.offset + value.length;
        for (int i = value.offset + fromIndex; i < end; ++i) {
            int c = value.ch[i];
            if (XMLChar.isSpace(c)) {
                value.ch[i] = ' ';
            }
        }
    }
    
    
Checks whether this string would be unchanged by normalization.
Returns:
-1 if the value would be unchanged by normalization,
otherwise the index of the first whitespace character which
would be transformed./**
     * Checks whether this string would be unchanged by normalization.
     * 
     * @return -1 if the value would be unchanged by normalization,
     * otherwise the index of the first whitespace character which
     * would be transformed.
     */
    protected int isUnchangedByNormalization(XMLString value) {
        int end = value.offset + value.length;
        for (int i = value.offset; i < end; ++i) {
            int c = value.ch[i];
            if (XMLChar.isSpace(c)) {
                return i - value.offset;
            }
        }
        return -1;
    }

    // returns true if the given character is not
    // valid with respect to the version of
    // XML understood by this scanner.
    protected boolean isInvalid(int value) {
        return (!XML11Char.isXML11Valid(value)); 
    } // isInvalid(int):  boolean

    // returns true if the given character is not
    // valid or may not be used outside a character reference 
    // with respect to the version of XML understood by this scanner.
    protected boolean isInvalidLiteral(int value) {
        return (!XML11Char.isXML11ValidLiteral(value)); 
    } // isInvalidLiteral(int):  boolean

    // returns true if the given character is 
    // a valid nameChar with respect to the version of
    // XML understood by this scanner.
    protected boolean isValidNameChar(int value) {
        return (XML11Char.isXML11Name(value)); 
    } // isValidNameChar(int):  boolean

    // returns true if the given character is 
    // a valid nameStartChar with respect to the version of
    // XML understood by this scanner.
    protected boolean isValidNameStartChar(int value) {
        return (XML11Char.isXML11NameStart(value)); 
    } // isValidNameStartChar(int):  boolean
    
    // returns true if the given character is
    // a valid NCName character with respect to the version of
    // XML understood by this scanner.
    protected boolean isValidNCName(int value) {
        return (XML11Char.isXML11NCName(value));
    } // isValidNCName(int):  boolean
    
    // returns true if the given character is 
    // a valid high surrogate for a nameStartChar 
    // with respect to the version of XML understood 
    // by this scanner.
    protected boolean isValidNameStartHighSurrogate(int value) {
        return XML11Char.isXML11NameHighSurrogate(value); 
    } // isValidNameStartHighSurrogate(int):  boolean

    // note that, according to 4.3.4 of the XML 1.1 spec, XML 1.1
    // documents may invoke 1.0 entities; thus either version decl (or none!)
    // is allowed to appear in this context
    protected boolean versionSupported(String version) {
        return version.equals("1.1") || version.equals ("1.0");
    } // versionSupported(String):  boolean
    
    // returns the error message key for unsupported
    // versions of XML with respect to the version of
    // XML understood by this scanner.
    protected String getVersionNotSupportedKey () {
        return "VersionNotSupported11";
    } // getVersionNotSupportedKey: String

} // class XML11DTDScannerImpl