/*

 * Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved.

 * 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.beans.decoder;

import java.beans.Expression;

import static java.util.Locale.ENGLISH;

/**

 * This class is intended to handle <object> element.

 * This element looks like <void> element,

 * but its value is always used as an argument for element

 * that contains this one.

 * <p>The following attributes are supported:

 * <dl>

 * <dt>class

 * <dd>the type is used for static methods and fields

 * <dt>method

 * <dd>the method name

 * <dt>property

 * <dd>the property name

 * <dt>index

 * <dd>the property index

 * <dt>field

 * <dd>the field name

 * <dt>idref

 * <dd>the identifier to refer to the variable

 * <dt>id

 * <dd>the identifier of the variable that is intended to store the result

 * </dl>

 *

 * @since 1.7

 *

 * @author Sergey A. Malenkov

 */

class ObjectElementHandler extends NewElementHandler {

    private String idref;

    private String field;

    private Integer index;

    private String property;

    private String method;

    /**

     * Parses attributes of the element.

     * The following attributes are supported:

     * <dl>

     * <dt>class

     * <dd>the type is used for static methods and fields

     * <dt>method

     * <dd>the method name

     * <dt>property

     * <dd>the property name

     * <dt>index

     * <dd>the property index

     * <dt>field

     * <dd>the field name

     * <dt>idref

     * <dd>the identifier to refer to the variable

     * <dt>id

     * <dd>the identifier of the variable that is intended to store the result

     * </dl>

     *

     * @param name   the attribute name

     * @param value  the attribute value

     */

    @Override

    public final void addAttribute(String name, String value) {

        if (name.equals("idref")) { // NON-NLS: the attribute name

            this.idref = value;

        } else if (name.equals("field")) { // NON-NLS: the attribute name

            this.field = value;

        } else if (name.equals("index")) { // NON-NLS: the attribute name

            this.index = Integer.valueOf(value);

            addArgument(this.index); // hack for compatibility

        } else if (name.equals("property")) { // NON-NLS: the attribute name

            this.property = value;

        } else if (name.equals("method")) { // NON-NLS: the attribute name

            this.method = value;

        } else {

            super.addAttribute(name, value);

        }

    }

    /**

     * Calculates the value of this element

     * if the field attribute or the idref attribute is set.

     */

    @Override

    public final void startElement() {

        if ((this.field != null) || (this.idref != null)) {

            getValueObject();

        }

    }

    /**

     * Tests whether the value of this element can be used

     * as an argument of the element that contained in this one.

     *

     * @return {@code true} if the value of this element can be used

     *         as an argument of the element that contained in this one,

     *         {@code false} otherwise

     */

    @Override

    protected boolean isArgument() {

        return true; // hack for compatibility

    }

    /**

     * Creates the value of this element.

     *

     * @param type  the base class

     * @param args  the array of arguments

     * @return the value of this element

     * @throws Exception if calculation is failed

     */

    @Override

    protected final ValueObject getValueObject(Class<?> type, Object[] args) throws Exception {

        if (this.field != null) {

            return ValueObjectImpl.create(FieldElementHandler.getFieldValue(getContextBean(), this.field));

        }

        if (this.idref != null) {

            return ValueObjectImpl.create(getVariable(this.idref));

        }

        Object bean = getContextBean();

        String name;

        if (this.index != null) {

            name = (args.length == 2)

                    ? PropertyElementHandler.SETTER

                    : PropertyElementHandler.GETTER;

        } else if (this.property != null) {

            name = (args.length == 1)

                    ? PropertyElementHandler.SETTER

                    : PropertyElementHandler.GETTER;

            if (0 < this.property.length()) {

                name += this.property.substring(0, 1).toUpperCase(ENGLISH) + this.property.substring(1);

            }

        } else {

            name = (this.method != null) && (0 < this.method.length())

                    ? this.method

                    : "new"; // NON-NLS: the constructor marker

        }

        Expression expression = new Expression(bean, name, args);

        return ValueObjectImpl.create(expression.getValue());

    }

}