/**
 * Redistribution and use of this software and associated documentation ("Software"), with or
 * without modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain copyright statements and notices. Redistributions
 * must also contain a copy of this document.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other materials provided with
 * the distribution.
 *
 * 3. The name "Exolab" must not be used to endorse or promote products derived from this Software
 * without prior written permission of Intalio, Inc. For written permission, please contact
 * info@exolab.org.
 *
 * 4. Products derived from this Software may not be called "Exolab" nor may "Exolab" appear in
 * their names without prior written permission of Intalio, Inc. Exolab is a registered trademark of
 * Intalio, Inc.
 *
 * 5. Due credit should be given to the Exolab Project (http://www.exolab.org/).
 *
 * THIS SOFTWARE IS PROVIDED BY INTALIO, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTALIO, INC. OR ITS
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
 * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Copyright 2001-2002 (C) Intalio Inc. All Rights Reserved.
 *
 * $Id$
 */

package org.exolab.castor.xml.schema.reader;

// -- imported classes and packages
import org.exolab.castor.xml.AttributeSet;
import org.exolab.castor.xml.Namespaces;
import org.exolab.castor.xml.XMLException;
import org.exolab.castor.xml.schema.Annotation;
import org.exolab.castor.xml.schema.Schema;
import org.exolab.castor.xml.schema.SchemaContext;
import org.exolab.castor.xml.schema.SchemaNames;
import org.exolab.castor.xml.schema.SimpleType;
import org.exolab.castor.xml.schema.Structure;
import org.exolab.castor.xml.schema.XMLType;
import org.exolab.castor.xml.schema.simpletypes.ListType;


/**
 * A class for unmarshalling list elements of a simpleType. Thanks to
 * <a href="mailto:cdchudasama@yahoo.com">Chetan Chudasama</a> for his help.
 * 
 * @author <a href="mailto:blandin@intalio.com">Arnaud Blandin</a>
 * @author <a href="mailto:kvsico@intalio.com">Keith Visco</a>
 * @version $Revision$
 **/
public class SimpleTypeListUnmarshaller extends ComponentReader {


  // --------------------/
  // - Member Variables -/
  // --------------------/

  /**
   * The current ComponentReader
   **/
  private ComponentReader unmarshaller;

  /**
   * The current branch depth
   **/
  private int depth = 0;

  /**
   * The simpleType we are unmarshalling
   **/
  private ListType _list = null;
  private Schema _schema = null;
  private boolean foundAnnotation = false;
  private boolean foundSimpleType = false;
  private boolean foundItemType = false;


  // ----------------/
  // - Constructors -/
  // ----------------/

  /**
   * Creates a new ListUnmarshaller.
   * 
   * @param schemaContext the {@link SchemaContext} to get some configuration settings from
   * @param atts the AttributeList
   **/
  SimpleTypeListUnmarshaller(final SchemaContext schemaContext, final Schema schema,
      final AttributeSet atts) throws XMLException {
    super(schemaContext);

    _schema = schema;
    _list = new ListType(schema);

    // -- itemType
    String itemTypeName = atts.getValue(SchemaNames.ITEM_TYPE_ATTR);
    if ((itemTypeName != null) && (itemTypeName.length() > 0)) {

      foundItemType = true;
      XMLType itemType = _schema.getType(itemTypeName);
      if (itemType == null) {
        _list.setItemType(itemTypeName);
      } else if (itemType.getStructureType() == Structure.COMPLEX_TYPE) {
        String err = "The item type of a list cannot " + "be a complexType.";
        throw new IllegalStateException(err);
      } else
        _list.setItemType((SimpleType) itemType);
    }

    // -- @id
    _list.setId(atts.getValue(SchemaNames.ID_ATTR));

  } // -- SimpleTypeListUnmarshaller

  // -----------/
  // - Methods -/
  // -----------/

  /**
   * Returns the name of the element that this ComponentReader handles
   * 
   * @return the name of the element that this ComponentReader handles
   **/
  public String elementName() {
    return SchemaNames.LIST;
  } // -- elementName

  /**
   * Called to signal an end of unmarshalling. This method should be overridden to perform any
   * necessary clean up by an unmarshaller
   **/
  public void finish() throws XMLException {
    if ((!foundItemType) && (!foundSimpleType)) {
      String err = "Missing sub-component of <list>, either use "
          + " the 'itemType' attribute, or an anonymous simpleType.";
      error(err);
    }
  } // -- finish

  /**
   * Returns the Object created by this ComponentReader
   * 
   * @return the Object created by this ComponentReader
   **/
  public Object getObject() {
    if ((!foundItemType) && (!foundSimpleType)) {
      String err = "Missing sub-component of <list>, either use "
          + " the 'itemType' attribute, or an anonymous simpleType.";
      throw new IllegalStateException(err);
    }
    return _list;
  } // -- getObject

  /**
   * Signals the start of an element with the given name.
   *
   * @param name the NCName of the element. It is an error if the name is a QName (ie. contains a
   *        prefix).
   * @param namespace the namespace of the element. This may be null. Note: A null namespace is not
   *        the same as the default namespace unless the default namespace is also null.
   * @param atts the AttributeSet containing the attributes associated with the element.
   * @param nsDecls the namespace declarations being declared for this element. This may be null.
   **/
  public void startElement(String name, String namespace, AttributeSet atts, Namespaces nsDecls)
      throws XMLException {
    // -- Do delagation if necessary
    if (unmarshaller != null) {
      unmarshaller.startElement(name, namespace, atts, nsDecls);
      ++depth;
      return;
    }


    // -- annotation
    if (name.equals(SchemaNames.ANNOTATION)) {

      if (foundSimpleType)
        error("An annotation must appear as the first child " + "of 'list' elements.");

      if (foundAnnotation)
        error("Only one (1) annotation may appear as a child of " + "'list' elements.");

      foundAnnotation = true;
      unmarshaller = new AnnotationUnmarshaller(getSchemaContext(), atts);
    } else if (SchemaNames.SIMPLE_TYPE.equals(name)) {
      if (foundItemType)
        error("A 'list' element can have either an 'itemType' or " + " 'simpleType'.");

      if (foundSimpleType)
        error("Only one (1) 'simpleType' may appear as a child of " + "'list' elements.");

      foundSimpleType = true;
      unmarshaller = new SimpleTypeUnmarshaller(getSchemaContext(), _schema, atts);

    } else
      illegalElement(name);

    unmarshaller.setDocumentLocator(getDocumentLocator());
  } // -- startElement

  /**
   * Signals to end of the element with the given name.
   *
   * @param name the NCName of the element. It is an error if the name is a QName (ie. contains a
   *        prefix).
   * @param namespace the namespace of the element.
   **/
  public void endElement(String name, String namespace) throws XMLException {

    // -- Do delagation if necessary
    if ((unmarshaller != null) && (depth > 0)) {
      unmarshaller.endElement(name, namespace);
      --depth;
      return;
    }

    // -- have unmarshaller perform any necessary clean up
    unmarshaller.finish();

    // -- annotation
    if (SchemaNames.ANNOTATION.equals(name)) {
      Annotation ann = ((AnnotationUnmarshaller) unmarshaller).getAnnotation();
      _list.setLocalAnnotation(ann);
    } else if (SchemaNames.SIMPLE_TYPE.equals(name)) {
      SimpleType type = (SimpleType) unmarshaller.getObject();
      _list.setItemType(type);
    }


    unmarshaller = null;
  } // -- endElement

  public void characters(char[] ch, int start, int length) throws XMLException {
    // -- Do delagation if necessary
    if (unmarshaller != null) {
      unmarshaller.characters(ch, start, length);
    }
  } // -- characters

} // -- SimpleTypeListUnmarshaller
