// Copyright 2006 Daniel Gredler

 //

 // 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 net.sf.beanform;

 import java.util.Map;

 import net.sf.beanform.prop.BeanProperty;

 import org.apache.hivemind.ApplicationRuntimeException;

 import org.apache.tapestry.BaseComponent;

 import org.apache.tapestry.IBinding;

 import org.apache.tapestry.IComponent;

 import org.apache.tapestry.IRequestCycle;

 import org.apache.tapestry.components.Block;

 import org.apache.tapestry.form.IFormComponent;

 import org.apache.tapestry.form.IPropertySelectionModel;

 /**

  * Superclass for low level BeanForm components which must be wrapped by

  * a {@link BeanForm} component.

  *

  * @see BeanFormRows

  * @see BeanFormLabel

  * @see BeanFormField

  * @see BeanFormButtons

  *

  * @author Daniel Gredler

  */

 public abstract class BeanFormComponent extends BaseComponent {

     final static String CUSTOM_FIELD_BLOCK_SUFFIX = "_BeanFieldBlock";

     final static String CUSTOM_FIELD_SUFFIX = "_BeanField";

     final static String BINDING_OVERRIDE_SEPARATOR = "_";

     final static String MODEL = "model";

     final static String MODEL_SUFFIX = BINDING_OVERRIDE_SEPARATOR + MODEL;

     protected BeanForm getBeanForm() {

         IRequestCycle cycle = this.getPage().getRequestCycle();

         BeanForm beanForm = (BeanForm) cycle.getAttribute( BeanForm.BEAN_FORM_ATTRIBUTE );

         if( beanForm == null ) throw new ApplicationRuntimeException( BeanFormMessages.noBeanForm( this ) );

         return beanForm;

     }

     protected boolean hasCustomField( BeanProperty property ) {

         return ( this.getCustomFieldBlock( property ) != null &&

                  this.getCustomField( property ) != null );

     }

     protected Block getCustomFieldBlock( BeanProperty property ) {

         String name = this.getCustomFieldBlockName( property );

         return this.getSiblingComponent( name, Block.class );

     }

     protected String getCustomFieldBlockName( BeanProperty property ) {

         return this.getBeanForm().getId() + "_" + property.getName() + CUSTOM_FIELD_BLOCK_SUFFIX;

     }

     protected IFormComponent getCustomField( BeanProperty property ) {

         String name = this.getCustomFieldName( property );

         return this.getSiblingComponent( name, IFormComponent.class );

     }

     protected String getCustomFieldName( BeanProperty property ) {

         return this.getBeanForm().getId() + "_" + property.getName() + CUSTOM_FIELD_SUFFIX;

     }

     @SuppressWarnings( "unchecked" )

     protected <T extends IComponent> T getSiblingComponent( String id, Class<T> clazz ) {

         IComponent component = null;

         IComponent container = this.getBeanForm().getContainer();

         Map components = container.getComponents();

         if( components.containsKey( id ) ) {

             IComponent candidate = (IComponent) components.get( id );

             if( clazz.isAssignableFrom( candidate.getClass() ) ) {

                 component = candidate;

             }

             else {

                 String msg = BeanFormMessages.componentUnexpectedType( candidate, clazz );

                 throw new ApplicationRuntimeException( msg );

             }

         }

         return (T) component;

     }

     protected boolean hasPropertySelectionModel( BeanProperty prop, boolean useCache ) {

         return this.getPropertySelectionModel( prop, useCache ) != null;

     }

     protected IPropertySelectionModel getPropertySelectionModel( BeanProperty prop, boolean useCache ) {

         IBinding binding;

         if( useCache ) binding = this.getBeanForm().getFieldBindingsFor( prop ).get( MODEL );

         else binding = this.getBeanForm().getBinding( prop.getName() + MODEL_SUFFIX );

         IPropertySelectionModel model = null;

         if( binding != null ) {

             Object value = binding.getObject();

             if( value instanceof IPropertySelectionModel ) {

                 model = (IPropertySelectionModel) value;

             }

         }

         return model;

     }

 }