/*
 * 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.parsers;

import org.apache.xerces.xni.Augmentations;
import org.apache.xerces.xni.NamespaceContext;
import org.apache.xerces.xni.QName;
import org.apache.xerces.xni.XMLAttributes;
import org.apache.xerces.xni.XMLDTDContentModelHandler;
import org.apache.xerces.xni.XMLDTDHandler;
import org.apache.xerces.xni.XMLDocumentHandler;
import org.apache.xerces.xni.XMLLocator;
import org.apache.xerces.xni.XMLResourceIdentifier;
import org.apache.xerces.xni.XMLString;
import org.apache.xerces.xni.XNIException;
import org.apache.xerces.xni.parser.XMLDTDContentModelSource;
import org.apache.xerces.xni.parser.XMLDTDSource;
import org.apache.xerces.xni.parser.XMLDocumentSource;
import org.apache.xerces.xni.parser.XMLParserConfiguration;

/**
 * This is the base class for all XML document parsers. XMLDocumentParser
 * provides a common implementation shared by the various document parsers
 * in the Xerces package. While this class is provided for convenience, it
 * does not prevent other kinds of parsers to be constructed using the XNI
 * interfaces.
 *
 * @author Arnaud  Le Hors, IBM
 * @author Andy Clark, IBM
 *
 * @version $Id: AbstractXMLDocumentParser.java 447239 2006-09-18 05:08:26Z mrglavas $
 */
public abstract class AbstractXMLDocumentParser
    extends XMLParser
    implements XMLDocumentHandler, XMLDTDHandler, XMLDTDContentModelHandler {

    //
    // Data
    //

    // state

    /** True if inside DTD. */
    protected boolean fInDTD;

    /** Document source*/
    protected XMLDocumentSource fDocumentSource;

    /** DTD source*/
    protected XMLDTDSource fDTDSource;

    /** DTD content model source*/
    protected XMLDTDContentModelSource fDTDContentModelSource;

    //
    // Constructors
    //

    /**
     * Constructs a document parser using the default symbol table
     * and grammar pool.
     */
    protected AbstractXMLDocumentParser(XMLParserConfiguration config) {
        super(config);

        // set handlers
        config.setDocumentHandler(this);
        config.setDTDHandler(this);
        config.setDTDContentModelHandler(this);

    } // <init>(XMLParserConfiguration)

    //
    // XMLDocumentHandler methods
    //

    /**
     * The start of the document.
     *
     * @param locator The system identifier of the entity if the entity
     *                 is external, null otherwise.
     * @param encoding The auto-detected IANA encoding name of the entity
     *                 stream. This value will be null in those situations
     *                 where the entity encoding is not auto-detected (e.g.
     *                 internal entities or a document entity that is
     *                 parsed from a java.io.Reader). 
     * @param namespaceContext
     *                 The namespace context in effect at the
     *                 start of this document.
     *                 This object represents the current context.
     *                 Implementors of this class are responsible
     *                 for copying the namespace bindings from the
     *                 the current context (and its parent contexts)
     *                 if that information is important.
     * @param augs   Additional information that may include infoset augmentations    
     *     
     * @throws XNIException Thrown by handler to signal an error.
     */

    public void startDocument(XMLLocator locator, String encoding, 
                              NamespaceContext namespaceContext, Augmentations augs) 
        throws XNIException {
    } // startDocument(XMLLocator,String)

    /**
     * Notifies of the presence of an XMLDecl line in the document. If
     * present, this method will be called immediately following the
     * startDocument call.
     * 
     * @param version    The XML version.
     * @param encoding   The IANA encoding name of the document, or null if
     *                   not specified.
     * @param standalone The standalone value, or null if not specified.
     * @param augs   Additional information that may include infoset augmentations
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void xmlDecl(String version, String encoding, String standalone, Augmentations augs)
        throws XNIException {
    } // xmlDecl(String,String,String)

    /**
     * Notifies of the presence of the DOCTYPE line in the document.
     * 
     * @param rootElement The name of the root element.
     * @param publicId    The public identifier if an external DTD or null
     *                    if the external DTD is specified using SYSTEM.
     * @param systemId    The system identifier if an external DTD, null
     * @param augs   Additional information that may include infoset augmentations
     *                    otherwise.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void doctypeDecl(String rootElement, String publicId, String systemId, Augmentations augs)
        throws XNIException {
    } // doctypeDecl(String,String,String)

    /**
     * The start of an element. If the document specifies the start element
     * by using an empty tag, then the startElement method will immediately
     * be followed by the endElement method, with no intervening methods.
     * 
     * @param element    The name of the element.
     * @param attributes The element attributes.
     * @param augs   Additional information that may include infoset augmentations
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void startElement(QName element, XMLAttributes attributes, Augmentations augs)
        throws XNIException {
    } // startElement(QName,XMLAttributes)

    /**
     * An empty element.
     * 
     * @param element    The name of the element.
     * @param attributes The element attributes.
     * @param augs   Additional information that may include infoset augmentations
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void emptyElement(QName element, XMLAttributes attributes, Augmentations augs)
        throws XNIException {

        startElement(element, attributes, augs);
        endElement(element, augs);

    } // emptyElement(QName,XMLAttributes)

    /**
     * Character content.
     * 
     * @param text The content.
     * @param augs   Additional information that may include infoset augmentations
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void characters(XMLString text, Augmentations augs) throws XNIException {
    } // characters(XMLString)

    /**
     * Ignorable whitespace. For this method to be called, the document
     * source must have some way of determining that the text containing
     * only whitespace characters should be considered ignorable. For
     * example, the validator can determine if a length of whitespace
     * characters in the document are ignorable based on the element
     * content model.
     * 
     * @param text The ignorable whitespace.
     * @param augs   Additional information that may include infoset augmentations
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void ignorableWhitespace(XMLString text, Augmentations augs) throws XNIException {
    } // ignorableWhitespace(XMLString)

    /**
     * The end of an element.
     * 
     * @param element The name of the element.
     * @param augs   Additional information that may include infoset augmentations
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void endElement(QName element, Augmentations augs) throws XNIException {
    } // endElement(QName)

    /** 
     * The start of a CDATA section. 
     * @param augs   Additional information that may include infoset augmentations
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void startCDATA(Augmentations augs) throws XNIException {
    } // startCDATA()

    /**
     * The end of a CDATA section.
     * @param augs   Additional information that may include infoset augmentations 
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void endCDATA(Augmentations augs) throws XNIException {
    } // endCDATA()

    /**
     * The end of the document.
     * @param augs   Additional information that may include infoset augmentations
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void endDocument(Augmentations augs) throws XNIException {
    } // endDocument()


    /**
     * This method notifies the start of an entity.
     * <p>
     * <strong>Note:</strong> This method is not called for entity references
     * appearing as part of attribute values.
     * 
     * @param name     The name of the entity.
     * @param identifier The resource identifier.
     * @param encoding The auto-detected IANA encoding name of the entity
     *                 stream. This value will be null in those situations
     *                 where the entity encoding is not auto-detected (e.g.
     *                 internal entities or a document entity that is
     *                 parsed from a java.io.Reader).
     * @param augs     Additional information that may include infoset augmentations
     *                 
     * @exception XNIException Thrown by handler to signal an error.
     */
    public void startGeneralEntity(String name, 
                                   XMLResourceIdentifier identifier,
                                   String encoding,
                                   Augmentations augs) throws XNIException {
    } // startGeneralEntity(String,XMLResourceIdentifier,String,Augmentations)

    /**
     * Notifies of the presence of a TextDecl line in an entity. If present,
     * this method will be called immediately following the startEntity call.
     * <p>
     * <strong>Note:</strong> This method will never be called for the
     * document entity; it is only called for external general entities
     * referenced in document content.
     * <p>
     * <strong>Note:</strong> This method is not called for entity references
     * appearing as part of attribute values.
     * 
     * @param version  The XML version, or null if not specified.
     * @param encoding The IANA encoding name of the entity.
     * @param augs     Additional information that may include infoset augmentations
     *                 
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void textDecl(String version, String encoding, Augmentations augs) throws XNIException {
    } // textDecl(String, String, Augmentations)
    
    /**
     * This method notifies the end of an entity.
     * <p>
     * <strong>Note:</strong> This method is not called for entity references
     * appearing as part of attribute values.
     * 
     * @param name   The name of the entity.
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void endGeneralEntity(String name, Augmentations augs) 
        throws XNIException {
    } // endGeneralEntity(String,Augmentations)
    
    /**
     * A comment.
     * 
     * @param text   The text in the comment.
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by application to signal an error.
     */
    public void comment(XMLString text, Augmentations augs) throws XNIException {
    } // comment (XMLString, Augmentations)

    /**
     * A processing instruction. Processing instructions consist of a
     * target name and, optionally, text data. The data is only meaningful
     * to the application.
     * <p>
     * Typically, a processing instruction's data will contain a series
     * of pseudo-attributes. These pseudo-attributes follow the form of
     * element attributes but are <strong>not</strong> parsed or presented
     * to the application as anything other than text. The application is
     * responsible for parsing the data.
     * 
     * @param target The target.
     * @param data   The data or null if none specified.
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void processingInstruction(String target, XMLString data, Augmentations augs)
        throws XNIException {
    } // processingInstruction(String, XMLString, Augmentations)

    
    /** Sets the document source */
    public void setDocumentSource(XMLDocumentSource source){
        fDocumentSource = source;
    } // setDocumentSource

    /** Returns the document source */
    public XMLDocumentSource getDocumentSource (){
        return fDocumentSource;
    } // getDocumentSource
    //
    // XMLDTDHandler methods
    //
    
    /**
     * The start of the DTD.
     *
     * @param locator  The document locator, or null if the document
     *                 location cannot be reported during the parsing of 
     *                 the document DTD. However, it is <em>strongly</em>
     *                 recommended that a locator be supplied that can 
     *                 at least report the base system identifier of the
     *                 DTD.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void startDTD(XMLLocator locator, Augmentations augs) throws XNIException {
        fInDTD = true;
    } // startDTD(XMLLocator)


    /**
     * The start of the DTD external subset.
     *
     * @param augmentations Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void startExternalSubset(XMLResourceIdentifier identifier, Augmentations augmentations) 
        throws XNIException {
    } // startExternalSubset(Augmentations)

    /**
     * The end of the DTD external subset.
     *
     * @param augmentations Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void endExternalSubset(Augmentations augmentations) 
        throws XNIException {
    } // endExternalSubset(Augmentations)

    /**
     * This method notifies the start of an entity.
     * <p>
     * <strong>Note:</strong> This method is not called for entity references
     * appearing as part of attribute values.
     * 
     * @param name     The name of the entity.
     * @param identifier The resource identifier.
     * @param encoding The auto-detected IANA encoding name of the entity
     *                 stream. This value will be null in those situations
     *                 where the entity encoding is not auto-detected (e.g.
     *                 internal entities or a document entity that is
     *                 parsed from a java.io.Reader).
     * @param augs     Additional information that may include infoset augmentations
     *                 
     * @exception XNIException Thrown by handler to signal an error.
     */
    public void startParameterEntity(String name, 
                                     XMLResourceIdentifier identifier,
                                     String encoding,
                                     Augmentations augs) throws XNIException {
    } // startParameterEntity(String,XMLResourceIdentifier,String,Augmentations)

    /**
     * This method notifies the end of an entity.
     * <p>
     * <strong>Note:</strong> This method is not called for entity references
     * appearing as part of attribute values.
     * 
     * @param name   The name of the entity.
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void endParameterEntity(String name, Augmentations augs) 
        throws XNIException {
    } // endParameterEntity(String,Augmentations)
    
    /**
     * Characters within an IGNORE conditional section.
     *
     * @param text The ignored text.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
     public void ignoredCharacters(XMLString text, Augmentations augs) throws XNIException {
     } // ignoredCharacters(XMLString, Augmentations)

    /**
     * An element declaration.
     * 
     * @param name         The name of the element.
     * @param contentModel The element content model.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void elementDecl(String name, String contentModel, Augmentations augs)
        throws XNIException {
    } // elementDecl(String,String)

    /**
     * The start of an attribute list.
     * 
     * @param elementName The name of the element that this attribute
     *                    list is associated with.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void startAttlist(String elementName, Augmentations augs) throws XNIException {
    } // startAttlist(String)

    /**
     * An attribute declaration.
     * 
     * @param elementName   The name of the element that this attribute
     *                      is associated with.
     * @param attributeName The name of the attribute.
     * @param type          The attribute type. This value will be one of
     *                      the following: "CDATA", "ENTITY", "ENTITIES",
     *                      "ENUMERATION", "ID", "IDREF", "IDREFS", 
     *                      "NMTOKEN", "NMTOKENS", or "NOTATION".
     * @param enumeration   If the type has the value "ENUMERATION" or
     *                      "NOTATION", this array holds the allowed attribute
     *                      values; otherwise, this array is null.
     * @param defaultType   The attribute default type. This value will be
     *                      one of the following: "#FIXED", "#IMPLIED",
     *                      "#REQUIRED", or null.
     * @param defaultValue  The attribute default value, or null if no
     *                      default value is specified.
     * @param nonNormalizedDefaultValue  The attribute default value with no normalization 
     *                      performed, or null if no default value is specified.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void attributeDecl(String elementName, String attributeName, 
                              String type, String[] enumeration, 
                              String defaultType, XMLString defaultValue, 
			      XMLString nonNormalizedDefaultValue, Augmentations augs)
        throws XNIException {
    } // attributeDecl(String,String,String,String[],String,XMLString, XMLString, Augmentations)

    /**
     * The end of an attribute list.
     *
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void endAttlist(Augmentations augs) throws XNIException {
    } // endAttlist()

    /**
     * An internal entity declaration.
     * 
     * @param name The name of the entity. Parameter entity names start with
     *             '%', whereas the name of a general entity is just the 
     *             entity name.
     * @param text The value of the entity.
     * @param nonNormalizedText The non-normalized value of the entity. This
     *             value contains the same sequence of characters that was in 
     *             the internal entity declaration, without any entity
     *             references expanded.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void internalEntityDecl(String name, XMLString text,
                                   XMLString nonNormalizedText, Augmentations augs) 
        throws XNIException {
    } // internalEntityDecl(String,XMLString,XMLString)

    /**
     * An external entity declaration.
     * 
     * @param name     The name of the entity. Parameter entity names start
     *                 with '%', whereas the name of a general entity is just
     *                 the entity name.
     * @param identifier    An object containing all location information 
     *                      pertinent to this entity.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void externalEntityDecl(String name, XMLResourceIdentifier identifier,
                                   Augmentations augs) throws XNIException {
    } // externalEntityDecl(String,XMLResourceIdentifier, Augmentations)

    /**
     * An unparsed entity declaration.
     * 
     * @param name     The name of the entity.
     * @param identifier    An object containing all location information 
     *                      pertinent to this entity.
     * @param notation The name of the notation.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void unparsedEntityDecl(String name, XMLResourceIdentifier identifier,
                                   String notation, Augmentations augs) throws XNIException {
    } // unparsedEntityDecl(String,XMLResourceIdentifier, String, Augmentations)

    /**
     * A notation declaration
     * 
     * @param name     The name of the notation.
     * @param identifier    An object containing all location information 
     *                      pertinent to this notation.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void notationDecl(String name, XMLResourceIdentifier identifier, 
    	Augmentations augs)
        throws XNIException {
    } // notationDecl(String,XMLResourceIdentifier, Augmentations)

    /**
     * The start of a conditional section.
     * 
     * @param type The type of the conditional section. This value will
     *             either be CONDITIONAL_INCLUDE or CONDITIONAL_IGNORE.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     *
     * @see #CONDITIONAL_INCLUDE
     * @see #CONDITIONAL_IGNORE
     */
    public void startConditional(short type, Augmentations augs) throws XNIException  {
    } // startConditional(short)

    /**
     * The end of a conditional section.
     *
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void endConditional(Augmentations augs) throws XNIException {
    } // endConditional()

    /**
     * The end of the DTD.
     *
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void endDTD(Augmentations augs) throws XNIException {
        fInDTD = false;
    } // endDTD()

    // set the source of this handler
    public void setDTDSource(XMLDTDSource source) {
        fDTDSource = source;
    }

    // return the source from which this handler derives its events
    public XMLDTDSource getDTDSource() {
        return fDTDSource;
    }

    //
    // XMLDTDContentModelHandler methods
    //

    /**
     * The start of a content model. Depending on the type of the content
     * model, specific methods may be called between the call to the
     * startContentModel method and the call to the endContentModel method.
     * 
     * @param elementName The name of the element.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void startContentModel(String elementName, Augmentations augs) throws XNIException {
    } // startContentModel(String, Augmentations)

    /** 
     * A content model of ANY. 
     *
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     *
     * @see #empty
     * @see #startGroup
     */
    public void any(Augmentations augs) throws XNIException {
    } // any(Augmentations)

    /**
     * A content model of EMPTY.
     *
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     *
     * @see #any
     * @see #startGroup
     */
    public void empty(Augmentations augs) throws XNIException {
    } // empty(Augmentations)

    /**
     * A start of either a mixed or children content model. A mixed
     * content model will immediately be followed by a call to the
     * <code>pcdata()</code> method. A children content model will
     * contain additional groups and/or elements.
     *
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     *
     * @see #any
     * @see #empty
     */
    public void startGroup(Augmentations augs) throws XNIException {
    } // stargGroup(Augmentations)

    /**
     * The appearance of "#PCDATA" within a group signifying a
     * mixed content model. This method will be the first called
     * following the content model's <code>startGroup()</code>.
     *
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *     
     * @throws XNIException Thrown by handler to signal an error.
     *
     * @see #startGroup
     */
    public void pcdata(Augmentations augs) throws XNIException {
    } // pcdata(Augmentations)

    /**
     * A referenced element in a mixed or children content model.
     * 
     * @param elementName The name of the referenced element.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void element(String elementName, Augmentations augs) throws XNIException {
    } // element(String, Augmentations)

    /**
     * The separator between choices or sequences of a mixed or children
     * content model.
     * 
     * @param separator The type of children separator.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     *
     * @see #SEPARATOR_CHOICE
     * @see #SEPARATOR_SEQUENCE
     */
    public void separator(short separator, Augmentations augs) throws XNIException {
    } // separator(short, Augmentations)

    /**
     * The occurrence count for a child in a children content model or
     * for the mixed content model group.
     * 
     * @param occurrence The occurrence count for the last element
     *                   or group.
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     *
     * @see #OCCURS_ZERO_OR_ONE
     * @see #OCCURS_ZERO_OR_MORE
     * @see #OCCURS_ONE_OR_MORE
     */
    public void occurrence(short occurrence, Augmentations augs) throws XNIException {
    } // occurence(short, Augmentations)

    /**
     * The end of a group for mixed or children content models.
     *
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void endGroup(Augmentations augs) throws XNIException {
    } // endGroup(Augmentations)

    /**
     * The end of a content model.
     *
     * @param augs Additional information that may include infoset
     *                      augmentations.
     *
     * @throws XNIException Thrown by handler to signal an error.
     */
    public void endContentModel(Augmentations augs) throws XNIException {
    } // endContentModel(Augmentations)

    // set content model source
    public void setDTDContentModelSource(XMLDTDContentModelSource source) {
        fDTDContentModelSource = source;
    }

    // get content model source
    public XMLDTDContentModelSource getDTDContentModelSource() {
        return fDTDContentModelSource;
    }

    //
    // Protected methods
    //

    /**
     * reset all components before parsing
     */
    protected void reset() throws XNIException {
        super.reset();
        fInDTD = false;
    } // reset()

} // class AbstractXMLDocumentParser
