/*

 */

/*

 * 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 com.sun.org.apache.xml.internal.utils;

import java.util.Stack;

import java.util.StringTokenizer;

import org.w3c.dom.Element;

/**

 * Class to represent a qualified name: "The name of an internal XSLT object,

 * specifically a named template (see [7 Named Templates]), a mode (see [6.7 Modes]),

 * an attribute set (see [8.1.4 Named Attribute Sets]), a key (see [14.2 Keys]),

 * a locale (see [14.3 Number Formatting]), a variable or a parameter (see

 * [12 Variables and Parameters]) is specified as a QName. If it has a prefix,

 * then the prefix is expanded into a URI reference using the namespace declarations

 * in effect on the attribute in which the name occurs. The expanded name

 * consisting of the local part of the name and the possibly null URI reference

 * is used as the name of the object. The default namespace is not used for

 * unprefixed names."

 * @xsl.usage general

 */

public class QName implements java.io.Serializable

{

    static final long serialVersionUID = 467434581652829920L;

  /**

   * The local name.

   * @serial

   */

  protected String _localName;

  /**

   * The namespace URI.

   * @serial

   */

  protected String _namespaceURI;

  /**

   * The namespace prefix.

   * @serial

   */

  protected String _prefix;

  /**

   * The XML namespace.

   */

  public static final String S_XMLNAMESPACEURI =

    "http://www.w3.org/XML/1998/namespace";

  /**

   * The cached hashcode, which is calculated at construction time.

   * @serial

   */

  private int m_hashCode;

  /**

   * Constructs an empty QName.

   * 20001019: Try making this public, to support Serializable? -- JKESS

   */

  public QName(){}

  /**

   * Constructs a new QName with the specified namespace URI and

   * local name.

   *

   * @param namespaceURI The namespace URI if known, or null

   * @param localName The local name

   */

  public QName(String namespaceURI, String localName)

  {

    this(namespaceURI, localName, false);

  }

  /**

   * Constructs a new QName with the specified namespace URI and

   * local name.

   *

   * @param namespaceURI The namespace URI if known, or null

   * @param localName The local name

   * @param validate If true the new QName will be validated and an IllegalArgumentException will

   *                 be thrown if it is invalid.

   */

  public QName(String namespaceURI, String localName, boolean validate)

  {

    // This check was already here.  So, for now, I will not add it to the validation

    // that is done when the validate parameter is true.

    if (localName == null)

      throw new IllegalArgumentException(XMLMessages.createXMLMessage(

            XMLErrorResources.ER_ARG_LOCALNAME_NULL, null)); //"Argument 'localName' is null");

    if (validate)

    {

        if (!XML11Char.isXML11ValidNCName(localName))

        {

            throw new IllegalArgumentException(XMLMessages.createXMLMessage(

            XMLErrorResources.ER_ARG_LOCALNAME_INVALID,null )); //"Argument 'localName' not a valid NCName");

        }

    }

    _namespaceURI = namespaceURI;

    _localName = localName;

    m_hashCode = toString().hashCode();

  }

  /**

   * Constructs a new QName with the specified namespace URI, prefix

   * and local name.

   *

   * @param namespaceURI The namespace URI if known, or null

   * @param prefix The namespace prefix is known, or null

   * @param localName The local name

   *

   */

  public QName(String namespaceURI, String prefix, String localName)

  {

     this(namespaceURI, prefix, localName, false);

  }

 /**

   * Constructs a new QName with the specified namespace URI, prefix

   * and local name.

   *

   * @param namespaceURI The namespace URI if known, or null

   * @param prefix The namespace prefix is known, or null

   * @param localName The local name

   * @param validate If true the new QName will be validated and an IllegalArgumentException will

   *                 be thrown if it is invalid.

   */

  public QName(String namespaceURI, String prefix, String localName, boolean validate)

  {

    // This check was already here.  So, for now, I will not add it to the validation

    // that is done when the validate parameter is true.

    if (localName == null)

      throw new IllegalArgumentException(XMLMessages.createXMLMessage(

            XMLErrorResources.ER_ARG_LOCALNAME_NULL, null)); //"Argument 'localName' is null");

    if (validate)

    {

        if (!XML11Char.isXML11ValidNCName(localName))

        {

            throw new IllegalArgumentException(XMLMessages.createXMLMessage(

            XMLErrorResources.ER_ARG_LOCALNAME_INVALID,null )); //"Argument 'localName' not a valid NCName");

        }

        if ((null != prefix) && (!XML11Char.isXML11ValidNCName(prefix)))

        {

            throw new IllegalArgumentException(XMLMessages.createXMLMessage(

            XMLErrorResources.ER_ARG_PREFIX_INVALID,null )); //"Argument 'prefix' not a valid NCName");

        }

    }

    _namespaceURI = namespaceURI;

    _prefix = prefix;

    _localName = localName;

    m_hashCode = toString().hashCode();

  }

  /**

   * Construct a QName from a string, without namespace resolution.  Good

   * for a few odd cases.

   *

   * @param localName Local part of qualified name

   *

   */

  public QName(String localName)

  {

    this(localName, false);

  }

  /**

   * Construct a QName from a string, without namespace resolution.  Good

   * for a few odd cases.

   *

   * @param localName Local part of qualified name

   * @param validate If true the new QName will be validated and an IllegalArgumentException will

   *                 be thrown if it is invalid.

   */

  public QName(String localName, boolean validate)

  {

    // This check was already here.  So, for now, I will not add it to the validation

    // that is done when the validate parameter is true.

    if (localName == null)

      throw new IllegalArgumentException(XMLMessages.createXMLMessage(

            XMLErrorResources.ER_ARG_LOCALNAME_NULL, null)); //"Argument 'localName' is null");

    if (validate)

    {

        if (!XML11Char.isXML11ValidNCName(localName))

        {

            throw new IllegalArgumentException(XMLMessages.createXMLMessage(

            XMLErrorResources.ER_ARG_LOCALNAME_INVALID,null )); //"Argument 'localName' not a valid NCName");

        }

    }

    _namespaceURI = null;

    _localName = localName;

    m_hashCode = toString().hashCode();

  }

  /**

   * Construct a QName from a string, resolving the prefix

   * using the given namespace stack. The default namespace is

   * not resolved.

   *

   * @param qname Qualified name to resolve

   * @param namespaces Namespace stack to use to resolve namespace

   */

  {

    this(qname, namespaces, false);

  }

  /**

   * Construct a QName from a string, resolving the prefix

   * using the given namespace stack. The default namespace is

   * not resolved.

   *

   * @param qname Qualified name to resolve

   * @param namespaces Namespace stack to use to resolve namespace

   * @param validate If true the new QName will be validated and an IllegalArgumentException will

   *                 be thrown if it is invalid.

   */

  {

    String namespace = null;

    String prefix = null;

    int indexOfNSSep = qname.indexOf(':');

    if (indexOfNSSep > 0)

    {

      prefix = qname.substring(0, indexOfNSSep);

      if (prefix.equals("xml"))

      {

        namespace = S_XMLNAMESPACEURI;

      }

      // Do we want this?

      else if (prefix.equals("xmlns"))

      {

        return;

      }

      else

      {

        int depth = namespaces.size();

        for (int i = depth - 1; i >= 0; i--)

        {

          while (null != ns)

          {

            if ((null != ns.m_prefix) && prefix.equals(ns.m_prefix))

            {

              namespace = ns.m_uri;

              i = -1;

              break;

            }

            ns = ns.m_next;

          }

        }

      }

      if (null == namespace)

      {

        throw new RuntimeException(

          XMLMessages.createXMLMessage(

            XMLErrorResources.ER_PREFIX_MUST_RESOLVE,

            new Object[]{ prefix }));  //"Prefix must resolve to a namespace: "+prefix);

      }

    }

    _localName = (indexOfNSSep < 0)

                 ? qname : qname.substring(indexOfNSSep + 1);

    if (validate)

    {

        if ((_localName == null) || (!XML11Char.isXML11ValidNCName(_localName)))

        {

           throw new IllegalArgumentException(XMLMessages.createXMLMessage(

            XMLErrorResources.ER_ARG_LOCALNAME_INVALID,null )); //"Argument 'localName' not a valid NCName");

        }

    }

    _namespaceURI = namespace;

    _prefix = prefix;

    m_hashCode = toString().hashCode();

  }

  /**

   * Construct a QName from a string, resolving the prefix

   * using the given namespace context and prefix resolver.

   * The default namespace is not resolved.

   *

   * @param qname Qualified name to resolve

   * @param namespaceContext Namespace Context to use

   * @param resolver Prefix resolver for this context

   */

  public QName(String qname, Element namespaceContext,

               PrefixResolver resolver)

  {

      this(qname, namespaceContext, resolver, false);

  }

  /**

   * Construct a QName from a string, resolving the prefix

   * using the given namespace context and prefix resolver.

   * The default namespace is not resolved.

   *

   * @param qname Qualified name to resolve

   * @param namespaceContext Namespace Context to use

   * @param resolver Prefix resolver for this context

   * @param validate If true the new QName will be validated and an IllegalArgumentException will

   *                 be thrown if it is invalid.

   */

  public QName(String qname, Element namespaceContext,

               PrefixResolver resolver, boolean validate)

  {

    _namespaceURI = null;

    int indexOfNSSep = qname.indexOf(':');

    if (indexOfNSSep > 0)

    {

      if (null != namespaceContext)

      {

        String prefix = qname.substring(0, indexOfNSSep);

        _prefix = prefix;

        if (prefix.equals("xml"))

        {

          _namespaceURI = S_XMLNAMESPACEURI;

        }

        // Do we want this?

        else if (prefix.equals("xmlns"))

        {

          return;

        }

        else

        {

          _namespaceURI = resolver.getNamespaceForPrefix(prefix,

                  namespaceContext);

        }

        if (null == _namespaceURI)

        {

          throw new RuntimeException(

            XMLMessages.createXMLMessage(

              XMLErrorResources.ER_PREFIX_MUST_RESOLVE,

              new Object[]{ prefix }));  //"Prefix must resolve to a namespace: "+prefix);

        }

      }

      else

      {

        // TODO: error or warning...

      }

    }

    _localName = (indexOfNSSep < 0)

                 ? qname : qname.substring(indexOfNSSep + 1);

    if (validate)

    {

        if ((_localName == null) || (!XML11Char.isXML11ValidNCName(_localName)))

        {

           throw new IllegalArgumentException(XMLMessages.createXMLMessage(

            XMLErrorResources.ER_ARG_LOCALNAME_INVALID,null )); //"Argument 'localName' not a valid NCName");

        }

    }

    m_hashCode = toString().hashCode();

  }

  /**

   * Construct a QName from a string, resolving the prefix

   * using the given namespace stack. The default namespace is

   * not resolved.

   *

   * @param qname Qualified name to resolve

   * @param resolver Prefix resolver for this context

   */

  public QName(String qname, PrefixResolver resolver)

  {

    this(qname, resolver, false);

  }

  /**

   * Construct a QName from a string, resolving the prefix

   * using the given namespace stack. The default namespace is

   * not resolved.

   *

   * @param qname Qualified name to resolve

   * @param resolver Prefix resolver for this context

   * @param validate If true the new QName will be validated and an IllegalArgumentException will

   *                 be thrown if it is invalid.

   */

  public QName(String qname, PrefixResolver resolver, boolean validate)

  {

        String prefix = null;

    _namespaceURI = null;

    int indexOfNSSep = qname.indexOf(':');

    if (indexOfNSSep > 0)

    {

      prefix = qname.substring(0, indexOfNSSep);

      if (prefix.equals("xml"))

      {

        _namespaceURI = S_XMLNAMESPACEURI;

      }

      else

      {

        _namespaceURI = resolver.getNamespaceForPrefix(prefix);

      }

      if (null == _namespaceURI)

      {

        throw new RuntimeException(

          XMLMessages.createXMLMessage(

            XMLErrorResources.ER_PREFIX_MUST_RESOLVE,

            new Object[]{ prefix }));  //"Prefix must resolve to a namespace: "+prefix);

      }

      _localName = qname.substring(indexOfNSSep + 1);

    }

    else if (indexOfNSSep == 0)

    {

      throw new RuntimeException(

         XMLMessages.createXMLMessage(

           XMLErrorResources.ER_NAME_CANT_START_WITH_COLON,

           null));

    }

    else

    {

      _localName = qname;

    }

    if (validate)

    {

        if ((_localName == null) || (!XML11Char.isXML11ValidNCName(_localName)))

        {

           throw new IllegalArgumentException(XMLMessages.createXMLMessage(

            XMLErrorResources.ER_ARG_LOCALNAME_INVALID,null )); //"Argument 'localName' not a valid NCName");

        }

    }

    m_hashCode = toString().hashCode();

    _prefix = prefix;

  }

  /**

   * Returns the namespace URI. Returns null if the namespace URI

   * is not known.

   *

   * @return The namespace URI, or null

   */

  public String getNamespaceURI()

  {

    return _namespaceURI;

  }

  /**

   * Returns the namespace prefix. Returns null if the namespace

   * prefix is not known.

   *

   * @return The namespace prefix, or null

   */

  public String getPrefix()

  {

    return _prefix;

  }

  /**

   * Returns the local part of the qualified name.

   *

   * @return The local part of the qualified name

   */

  public String getLocalName()

  {

    return _localName;

  }

  /**

   * Return the string representation of the qualified name, using the

   * prefix if available, or the '{ns}foo' notation if not. Performs

   * string concatenation, so beware of performance issues.

   *

   * @return the string representation of the namespace

   */

  public String toString()

  {

    return _prefix != null

           ? (_prefix + ":" + _localName)

           : (_namespaceURI != null