// Copyright 2008 Thiago H. de Paula Figueiredo

 //

 // 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 br.com.arsmachina.tapestrycrud.services.impl;

 import java.util.HashMap;

 import java.util.Map;

 import org.apache.tapestry5.PrimaryKeyEncoder;

 import org.apache.tapestry5.ioc.util.StrategyRegistry;

 import br.com.arsmachina.tapestrycrud.encoder.ActivationContextEncoder;

 import br.com.arsmachina.tapestrycrud.services.ActivationContextEncoderSource;

 import br.com.arsmachina.tapestrycrud.services.EncoderSource;

 import br.com.arsmachina.tapestrycrud.services.PrimaryKeyEncoderSource;

 import br.com.arsmachina.tapestrycrud.services.PrimaryKeyTypeService;

 /**

  * {@link ActivationContextEncoderSource} implementation.

  * 

  * @author Thiago H. de Paula Figueiredo

  */

 public class ActivationContextEncoderSourceImpl implements ActivationContextEncoderSource {

         @SuppressWarnings("unchecked")

         final private StrategyRegistry<ActivationContextEncoder> registry;

         final private EncoderSource encoderSource;

         final private PrimaryKeyEncoderSource primaryKeyEncoderSource;

         final private PrimaryKeyTypeService primaryKeyTypeService;

         @SuppressWarnings("unchecked")

         final private Map<Class, ActivationContextEncoder> additionalEncoders = new HashMap<Class, ActivationContextEncoder>();

         /**

          * Single constructor.

          * 

          * @param registrations

          */

         @SuppressWarnings("unchecked")

         public ActivationContextEncoderSourceImpl(Map<Class, ActivationContextEncoder> registrations,

                         EncoderSource encoderSource, PrimaryKeyEncoderSource primaryKeyEncoderSource,

                         PrimaryKeyTypeService primaryKeyTypeService) {

                 if (registrations == null) {

                         throw new IllegalArgumentException("Parameter registrations cannot be null");

                 }

                 if (encoderSource == null) {

                         throw new IllegalArgumentException("Parameter encoderSource cannot be null");

                 }

                 if (primaryKeyTypeService == null) {

                         throw new IllegalArgumentException("Parameter primaryKeyTypeService cannot be null");

                 }

                 registry = StrategyRegistry.newInstance(ActivationContextEncoder.class, registrations, true);

                 this.encoderSource = encoderSource;

                 this.primaryKeyEncoderSource = primaryKeyEncoderSource;

                 this.primaryKeyTypeService = primaryKeyTypeService;

         }

         @SuppressWarnings("unchecked")

         public <T> ActivationContextEncoder<T> get(Class<T> clasz) {

                 ActivationContextEncoder<T> encoder = registry.get(clasz);

                 if (encoder == null) {

                         encoder = encoderSource.get(clasz);

                 }

                 if (encoder == null) {

                         encoder = additionalEncoders.get(clasz);

                         if (encoder == null) {

                                 PrimaryKeyEncoder<?, T> primaryKeyEncoder = primaryKeyEncoderSource.get(clasz);

                                 if (primaryKeyEncoder != null) {

                                         Class primaryKeyType = primaryKeyTypeService.getPrimaryKeyType(clasz);

                                         encoder = 

                                                 new PrimaryKeyEncoderActivationContextEncoder(primaryKeyEncoder, primaryKeyType);

                                         additionalEncoders.put(clasz, encoder);

                                 }

                         }

                 }

                 if (encoder == null) {

                         throw new IllegalArgumentException(

                                         "There is no ActivationContextEncoder configured for class " + clasz.getName());

                 }

                 return encoder;

         }

 }