// Attributes2Impl.java - extended AttributesImpl
// http://www.saxproject.org
// Public Domain: no warranty.
// $Id: Attributes2Impl.java,v 1.1 2004/12/23 22:38:42 mark Exp $

package org.xml.sax.ext;

import org.xml.sax.Attributes;
import org.xml.sax.helpers.AttributesImpl;


/**
 * SAX2 extension helper for additional Attributes information,
 * implementing the {@link Attributes2} interface.
 *
 * <blockquote>
 * <em>This module, both source code and documentation, is in the
 * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
 * </blockquote>
 *
 * <p>This is not part of core-only SAX2 distributions.</p>
 *
 * <p>The <em>specified</em> flag for each attribute will always
 * be true, unless it has been set to false in the copy constructor
 * or using {@link #setSpecified}.
 * Similarly, the <em>declared</em> flag for each attribute will
 * always be false, except for defaulted attributes (<em>specified</em>
 * is false), non-CDATA attributes, or when it is set to true using
 * {@link #setDeclared}.
 * If you change an attribute's type by hand, you may need to modify
 * its <em>declared</em> flag to match. 
 * </p>
 *
 * @since SAX 2.0 (extensions 1.1 alpha)
 * @author David Brownell
 * @version TBS
 */
public class Attributes2Impl extends AttributesImpl implements Attributes2
{
    private boolean	declared [];
    private boolean	specified [];


    /**
     * Construct a new, empty Attributes2Impl object.
     */
    public Attributes2Impl () { }


    /**
     * Copy an existing Attributes or Attributes2 object.
     * If the object implements Attributes2, values of the
     * <em>specified</em> and <em>declared</em> flags for each
     * attribute are copied.
     * Otherwise the flag values are defaulted to assume no DTD was used,
     * unless there is evidence to the contrary (such as attributes with
     * type other than CDATA, which must have been <em>declared</em>).
     *
     * <p>This constructor is especially useful inside a
     * {@link org.xml.sax.ContentHandler#startElement startElement} event.</p>
     *
     * @param atts The existing Attributes object.
     */
    public Attributes2Impl (Attributes atts)
    {
	super (atts);
    }


    ////////////////////////////////////////////////////////////////////
    // Implementation of Attributes2
    ////////////////////////////////////////////////////////////////////


    /**
     * Returns the current value of the attribute's "declared" flag.
     */
    // javadoc mostly from interface
    public boolean isDeclared (int index)
    {
	if (index < 0 || index >= getLength ())
	    throw new ArrayIndexOutOfBoundsException (
		"No attribute at index: " + index);
	return declared [index];
    }


    /**
     * Returns the current value of the attribute's "declared" flag.
     */
    // javadoc mostly from interface
    public boolean isDeclared (String uri, String localName)
    {
	int index = getIndex (uri, localName);

	if (index < 0)
	    throw new IllegalArgumentException (
		"No such attribute: local=" + localName
		+ ", namespace=" + uri);
	return declared [index];
    }


    /**
     * Returns the current value of the attribute's "declared" flag.
     */
    // javadoc mostly from interface
    public boolean isDeclared (String qName)
    {
	int index = getIndex (qName);

	if (index < 0)
	    throw new IllegalArgumentException (
		"No such attribute: " + qName);
	return declared [index];
    }


    /**
     * Returns the current value of an attribute's "specified" flag.
     *
     * @param index The attribute index (zero-based).
     * @return current flag value
     * @exception java.lang.ArrayIndexOutOfBoundsException When the
     *            supplied index does not identify an attribute.
     */
    public boolean isSpecified (int index)
    {
	if (index < 0 || index >= getLength ())
	    throw new ArrayIndexOutOfBoundsException (
		"No attribute at index: " + index);
	return specified [index];
    }


    /**
     * Returns the current value of an attribute's "specified" flag.
     *
     * @param uri The Namespace URI, or the empty string if
     *        the name has no Namespace URI.
     * @param localName The attribute's local name.
     * @return current flag value
     * @exception java.lang.IllegalArgumentException When the
     *            supplied names do not identify an attribute.
     */
    public boolean isSpecified (String uri, String localName)
    {
	int index = getIndex (uri, localName);

	if (index < 0)
	    throw new IllegalArgumentException (
		"No such attribute: local=" + localName
		+ ", namespace=" + uri);
	return specified [index];
    }


    /**
     * Returns the current value of an attribute's "specified" flag.
     *
     * @param qName The XML qualified (prefixed) name.
     * @return current flag value
     * @exception java.lang.IllegalArgumentException When the
     *            supplied name does not identify an attribute.
     */
    public boolean isSpecified (String qName)
    {
	int index = getIndex (qName);

	if (index < 0)
	    throw new IllegalArgumentException (
		"No such attribute: " + qName);
	return specified [index];
    }


    ////////////////////////////////////////////////////////////////////
    // Manipulators
    ////////////////////////////////////////////////////////////////////


    /**
     * Copy an entire Attributes object.  The "specified" flags are
     * assigned as true, and "declared" flags as false (except when
     * an attribute's type is not CDATA),
     * unless the object is an Attributes2 object.
     * In that case those flag values are all copied.
     *
     * @see AttributesImpl#setAttributes
     */
    public void setAttributes (Attributes atts)
    {
	int length = atts.getLength ();

	super.setAttributes (atts);
	declared = new boolean [length];
	specified = new boolean [length];

	if (atts instanceof Attributes2) {
	    Attributes2	a2 = (Attributes2) atts;
	    for (int i = 0; i < length; i++) {
		declared [i] = a2.isDeclared (i);
		specified [i] = a2.isSpecified (i);
	    }
	} else {
	    for (int i = 0; i < length; i++) {
		declared [i] = !"CDATA".equals (atts.getType (i));
		specified [i] = true;
	    }
	}
    }


    /**
     * Add an attribute to the end of the list, setting its
     * "specified" flag to true.  To set that flag's value
     * to false, use {@link #setSpecified}.
     *
     * <p>Unless the attribute <em>type</em> is CDATA, this attribute
     * is marked as being declared in the DTD.  To set that flag's value
     * to true for CDATA attributes, use {@link #setDeclared}.
     *
     * @see AttributesImpl#addAttribute
     */
    public void addAttribute (String uri, String localName, String qName,
			      String type, String value)
    {
	super.addAttribute (uri, localName, qName, type, value);

	int length = getLength ();

	if (length < specified.length) {
	    boolean	newFlags [];

	    newFlags = new boolean [length];
	    System.arraycopy (declared, 0, newFlags, 0, declared.length);
	    declared = newFlags;

	    newFlags = new boolean [length];
	    System.arraycopy (specified, 0, newFlags, 0, specified.length);
	    specified = newFlags;
	}

	specified [length - 1] = true;
	declared [length - 1] = !"CDATA".equals (type);
    }


    // javadoc entirely from superclass
    public void removeAttribute (int index)
    {
	int origMax = getLength () - 1;

	super.removeAttribute (index);
	if (index != origMax) {
	    System.arraycopy (declared, index + 1, declared, index,
		    origMax - index);
	    System.arraycopy (specified, index + 1, specified, index,
		    origMax - index);
	}
    }


    /**
     * Assign a value to the "declared" flag of a specific attribute.
     * This is normally needed only for attributes of type CDATA,
     * including attributes whose type is changed to or from CDATA.
     *
     * @param index The index of the attribute (zero-based).
     * @param value The desired flag value.
     * @exception java.lang.ArrayIndexOutOfBoundsException When the
     *            supplied index does not identify an attribute.
     * @see #setType
     */
    public void setDeclared (int index, boolean value)
    {
	if (index < 0 || index >= getLength ())
	    throw new ArrayIndexOutOfBoundsException (
		"No attribute at index: " + index);
	declared [index] = value;
    }


    /**
     * Assign a value to the "specified" flag of a specific attribute.
     * This is the only way this flag can be cleared, except clearing
     * by initialization with the copy constructor.
     *
     * @param index The index of the attribute (zero-based).
     * @param value The desired flag value.
     * @exception java.lang.ArrayIndexOutOfBoundsException When the
     *            supplied index does not identify an attribute.
     */
    public void setSpecified (int index, boolean value)
    {
	if (index < 0 || index >= getLength ())
	    throw new ArrayIndexOutOfBoundsException (
		"No attribute at index: " + index);
	specified [index] = value;
    }
}