/*******************************************************************************

 * * Copyright 2011 Impetus Infotech.

 *  *

 *  * Licensed 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.impetus.kundera.metadata.processor;



import java.beans.BeanInfo;

import java.beans.IntrospectionException;

import java.beans.Introspector;

import java.beans.PropertyDescriptor;

import java.lang.reflect.Field;

import java.util.Date;



import javax.persistence.Basic;

import javax.persistence.Column;

import javax.persistence.Temporal;



import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;



import com.impetus.kundera.metadata.EntityMetadata;

import com.impetus.kundera.metadata.MetadataProcessor;



/**

 * The Class AbstractEntityFieldProcessor.

 *

 * @author animesh.kumar

 */

public abstract class AbstractEntityFieldProcessor implements MetadataProcessor

{



    /** The Constant log. */

    private static final Log log = LogFactory.getLog(AbstractEntityFieldProcessor.class);



    /**

     * Gets the valid jpa column.

     *

     * @param entity

     *            the entity

     * @param f

     *            the f

     *

     * @return the valid jpa column

     */

    protected final String getValidJPAColumnName(Class<?> entity, Field f)

    {



        String name = null;



        if (f.isAnnotationPresent(Column.class))

        {

            Column c = f.getAnnotation(Column.class);

            if (!c.name().isEmpty())

            {

                name = c.name();

            }

            else

            {

                name = f.getName();

            }

        }

        else if (f.isAnnotationPresent(Basic.class))

        {

            name = f.getName();

        }



        if (f.isAnnotationPresent(Temporal.class))

        {

            if (!f.getType().equals(Date.class))

            {

                log.error("@Temporal must map to java.util.Date for @Entity(" + entity.getName() + "." + f.getName()

                        + ")");

                return name;

            }

            if (null == name)

            {

                name = f.getName();

            }

        }

        return name;

    }



    /**

     * Populates @Id accesser methods like, getId and setId of clazz to

     * metadata.

     *

     * @param metadata

     *            the metadata

     * @param clazz

     *            the clazz

     * @param f

     *            the f

     */

    protected final void populateIdAccessorMethods(EntityMetadata metadata, Class<?> clazz, Field f)

    {

        try

        {

            BeanInfo info = Introspector.getBeanInfo(clazz);



            for (PropertyDescriptor descriptor : info.getPropertyDescriptors())

            {

                if (descriptor.getName().equals(f.getName()))

                {

                    metadata.setReadIdentifierMethod(descriptor.getReadMethod());

                    metadata.setWriteIdentifierMethod(descriptor.getWriteMethod());

                    return;

                }

            }

        }

        catch (IntrospectionException e)

        {

            throw new RuntimeException(e);

        }

    }



    protected final void populateIdColumn(EntityMetadata metadata, Class<?> clazz, Field f)

    {

        if (f.isAnnotationPresent(Column.class))

        {

            Column c = f.getAnnotation(Column.class);

            if (!c.name().isEmpty())

            {

                metadata.setIdColumn(metadata.new Column(c.name(), f));

            }

            else

            {

                metadata.setIdColumn(metadata.new Column(f.getName(), f));

            }

        }

        else

        {

            metadata.setIdColumn(metadata.new Column(f.getName(), f));

        }

    }



}