// Copyright 2007, 2008 The Apache Software Foundation

 //

 // 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 org.apache.tapestry5.corelib.components;

 import org.apache.tapestry5.BindingConstants;

 import org.apache.tapestry5.ComponentAction;

 import org.apache.tapestry5.ComponentResources;

 import org.apache.tapestry5.PropertyOverrides;

 import org.apache.tapestry5.annotations.Environmental;

 import org.apache.tapestry5.annotations.Parameter;

 import org.apache.tapestry5.annotations.Property;

 import org.apache.tapestry5.annotations.SupportsInformalParameters;

 import org.apache.tapestry5.beaneditor.BeanModel;

 import org.apache.tapestry5.corelib.internal.InternalMessages;

 import org.apache.tapestry5.internal.beaneditor.BeanModelUtils;

 import org.apache.tapestry5.ioc.annotations.Inject;

 import org.apache.tapestry5.ioc.internal.util.TapestryException;

 import org.apache.tapestry5.services.BeanEditContext;

 import org.apache.tapestry5.services.BeanModelSource;

 import org.apache.tapestry5.services.Environment;

 import org.apache.tapestry5.services.FormSupport;

 import java.lang.annotation.Annotation;

 /**

  * A component that generates a user interface for editing the properties of a bean. This is the central component of

  * the {@link BeanEditForm}, and utilizes a {@link PropertyEditor} for much of its functionality. This component places

  * a {@link BeanEditContext} into the environment.

  */

 @SupportsInformalParameters

 public class BeanEditor

 {

     public static class Prepare implements ComponentAction<BeanEditor>

     {

         private static final long serialVersionUID = 6273600092955522585L;

         public void execute(BeanEditor component)

         {

             component.doPrepare();

         }

         @Override

         public String toString()

         {

             return "BeanEditor.Prepare";

         }

     }

     static class CleanupEnvironment implements ComponentAction<BeanEditor>

     {

         private static final long serialVersionUID = 6867226962459227016L;

         public void execute(BeanEditor component)

         {

             component.cleanupEnvironment();

         }

         @Override

         public String toString()

         {

             return "BeanEditor.CleanupEnvironment";

         }

     }

     private static final ComponentAction<BeanEditor> CLEANUP_ENVIRONMENT = new CleanupEnvironment();

     /**

      * The object to be edited by the BeanEditor. This will be read when the component renders and updated when the form

      * for the component is submitted. Typically, the container will listen for a "prepare" event, in order to ensure

      * that a non-null value is ready to be read or updated.

      */

     @Parameter(autoconnect = true)

     private Object object;

     /**

      * A comma-separated list of property names to be retained from the {@link org.apache.tapestry5.beaneditor.BeanModel}.

      * Only these properties will be retained, and the properties will also be reordered. The names are

      * case-insensitive.

      */

     @Parameter(defaultPrefix = BindingConstants.LITERAL)

     private String include;

     /**

      * A comma-separated list of property names to be removed from the {@link org.apache.tapestry5.beaneditor.BeanModel}.

      * The names are case-insensitive.

      */

     @Parameter(defaultPrefix = BindingConstants.LITERAL)

     private String exclude;

     /**

      * A comma-separated list of property names indicating the order in which the properties should be presented. The

      * names are case insensitive. Any properties not indicated in the list will be appended to the end of the display

      * order.

      */

     @Parameter(defaultPrefix = BindingConstants.LITERAL)

     private String reorder;

     /**

      * A comma-separated list of property names to be added to the {@link org.apache.tapestry5.beaneditor.BeanModel}.

      */

     @Parameter(defaultPrefix = BindingConstants.LITERAL)

     private String add;

     /**

      * The model that identifies the parameters to be edited, their order, and every other aspect. If not specified, a

      * default bean model will be created from the type of the object bound to the object parameter.

      */

     @Parameter

     @Property(write = false)

     private BeanModel model;

     /**

      * Where to search for local overrides of property editing blocks as block parameters. Further, the container of the

      * overrides is used as the source for overridden validation messages. This is normally the BeanEditor component

      * itself, but when the component is used within a BeanEditForm, it will be the BeanEditForm's resources that will

      * be searched.

      */

     @Parameter(value = "this", allowNull = false)

     @Property(write = false)

     private PropertyOverrides overrides;

     @Inject

     private BeanModelSource modelSource;

     @Inject

     private ComponentResources resources;

     @Inject

     private Environment environment;

     @Environmental

     private FormSupport formSupport;

     // Value that change with each change to the current property:

     @Property

     private String propertyName;

     /**

      * To support nested BeanEditors, we need to cache the object value inside {@link #doPrepare()}. See TAPESTRY-2460.

      */

     private Object cachedObject;

     // Needed for testing as well

     public Object getObject()

     {

         return cachedObject;

     }

     void setupRender()

     {

         formSupport.storeAndExecute(this, new Prepare());

     }

     void cleanupRender()

     {

         formSupport.storeAndExecute(this, CLEANUP_ENVIRONMENT);

     }

     /**

      * Used to initialize the model if necessary, to instantiate the object being edited if necessary, and to push the

      * BeanEditContext into the environment.

      */

     void doPrepare()

     {

         if (model == null)

         {

             Class type = resources.getBoundType("object");

             model = modelSource.createEditModel(type, overrides.getOverrideMessages());

         }

         BeanModelUtils.modify(model, add, include, exclude, reorder);

         // The only problem here is that if the bound property is backed by a persistent field, it

         // is assigned (and stored to the session, and propagated around the cluster) first,

         // before values are assigned.

         if (object == null)

         {

             try

             {

                 object = model.newInstance();

             }

             catch (Exception ex)

             {

                 String message = InternalMessages.failureInstantiatingObject(model.getBeanType(),

                                                                              resources.getCompleteId(),

                                                                              ex);

                 throw new TapestryException(message, resources.getLocation(), ex);

             }

         }

         BeanEditContext context = new BeanEditContext()

         {

             public Class<?> getBeanClass()

             {

                 return model.getBeanType();

             }

             public <T extends Annotation> T getAnnotation(Class<T> type)

             {

                 return getBeanClass().getAnnotation(type);

             }

         };

         cachedObject = object;

         environment.push(BeanEditContext.class, context);

     }

     void cleanupEnvironment()

     {

         environment.pop(BeanEditContext.class);

     }

     // For testing

     void inject(ComponentResources resources, PropertyOverrides overrides, BeanModelSource source,

                 Environment environment)

     {

         this.resources = resources;

         this.overrides = overrides;

         this.environment = environment;

         modelSource = source;

     }

 }