/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package com.sun.xml.internal.bind.v2.runtime.unmarshaller;

import java.util.Collection;

import javax.xml.bind.JAXBElement;

import javax.xml.namespace.QName;

import com.sun.xml.internal.bind.DatatypeConverterImpl;

import com.sun.xml.internal.bind.api.AccessorException;

import com.sun.xml.internal.bind.v2.WellKnownNamespace;

import com.sun.xml.internal.bind.v2.runtime.reflect.Accessor;

import org.xml.sax.SAXException;

/**

 * Looks for xsi:nil='true' and sets the target to null.

 * Otherwise delegate to another handler.

 *

 * @author Kohsuke Kawaguchi

 */

public class XsiNilLoader extends ProxyLoader {

    private final Loader defaultLoader;

    public XsiNilLoader(Loader defaultLoader) {

        this.defaultLoader = defaultLoader;

        assert defaultLoader!=null;

    }

    protected Loader selectLoader(UnmarshallingContext.State state, TagName ea) throws SAXException {

        int idx = ea.atts.getIndex(WellKnownNamespace.XML_SCHEMA_INSTANCE,"nil");

        if (idx!=-1) {

            Boolean b = DatatypeConverterImpl._parseBoolean(ea.atts.getValue(idx));

            if (b != null && b) {

                onNil(state);

                boolean hasOtherAttributes = (ea.atts.getLength() - 1) > 0;

                // see issues 6759703 and 565 - need to preserve attributes even if the element is nil; only when the type is stored in JAXBElement

                if (!(hasOtherAttributes && (state.prev.target instanceof JAXBElement))) {

                    return Discarder.INSTANCE;

                }

            }

        }

        return defaultLoader;

    }

        @Override

        public Collection<QName> getExpectedChildElements() {

            return defaultLoader.getExpectedChildElements();

        }

        @Override

        public Collection<QName> getExpectedAttributes() {

            return defaultLoader.getExpectedAttributes();

        }

    /**

     * Called when xsi:nil='true' was found.

     */

    protected void onNil(UnmarshallingContext.State state) throws SAXException {

    }

    public static final class Single extends XsiNilLoader {

        private final Accessor acc;

        public Single(Loader l, Accessor acc) {

            super(l);

            this.acc = acc;

        }

        @Override

        protected void onNil(UnmarshallingContext.State state) throws SAXException {

            try {

                acc.set(state.prev.target,null);

                state.prev.nil = true;

            } catch (AccessorException e) {

                handleGenericException(e,true);

            }

        }

    }

    public static final class Array extends XsiNilLoader {

        public Array(Loader core) {

            super(core);

        }

        @Override

        protected void onNil(UnmarshallingContext.State state) {

            // let the receiver add this to the lister

            state.target = null;

        }

    }

}