/*

  * Copyright 2011 The Kuali Foundation

  *

  * Licensed under the Educational Community License, Version 1.0 (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.opensource.org/licenses/ecl1.php

  *

  * 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.kuali.rice.kns.uif.modifier;

 import java.util.HashSet;

 import java.util.List;

 import java.util.Set;

 import org.kuali.rice.kns.uif.container.View;

 import org.kuali.rice.kns.uif.core.Component;

 import org.kuali.rice.kns.uif.util.ComponentUtils;

 import org.kuali.rice.kns.uif.util.ObjectPropertyUtils;

 /**

  * For a given <code>Component</code> instance converts all component properties

  * of a certain type to instances of another configured <code>Component</code>.

  * The conversion is performed recursively down all the component children

  * 

  * <p>

  * Some example uses of this are converting all checkbox controls to radio group

  * controls within a group and replacement of a widget with another

  * </p>

  * 

  * @author Kuali Rice Team (rice.collab@kuali.org)

  */

 public class ComponentConvertModifier extends ComponentModifierBase {

         private static final long serialVersionUID = -7566547737669924605L;

         private Class<? extends Component> componentTypeToReplace;

         private Component componentReplacementPrototype;

         public ComponentConvertModifier() {

                 super();

         }

         /**

          * @see org.kuali.rice.kns.uif.modifier.ComponentModifier#performModification(org.kuali.rice.kns.uif.container.View,

          *      org.kuali.rice.kns.uif.core.Component)

          */

         @Override

         public void performModification(View view, Component component) {

                 if (component == null) {

                         return;

                 }

                 int idSuffix = 0;

                 convertToReplacement(component, idSuffix);

         }

         /**

          * Reads the component properties and looks for types that match the

          * configured type to replace. If a match is found, a new instance of the

          * replacement component prototype is created and set as the property value.

          * The method is then called for each of the component's children

          * 

          * @param component

          *            - component instance to inspect properties for

          * @param idSuffix

          *            - suffix string to use for any generated component

          *            replacements

          */

         protected void convertToReplacement(Component component, int idSuffix) {

                 if (component == null) {

                         return;

                 }

                 // check all component properties for the type to replace

                 List<String> componentProperties = ComponentUtils.getComponentPropertyNames(component.getClass());

                 for (String propertyPath : componentProperties) {

                         Object propValue = ObjectPropertyUtils.getPropertyValue(component, propertyPath);

                         if (propValue != null) {

                                 if (getComponentTypeToReplace().isAssignableFrom(propValue.getClass())) {

                                         // types match, convert the component

                                         performConversion(component, propertyPath, idSuffix++);

                                 }

                         }

                 }

                 // recursively update components

                 for (Component nestedComponent : component.getNestedComponents()) {

                         convertToReplacement(nestedComponent, idSuffix);

                 }

         }

         /**

          * Creates a new instance of the replacement component prototype and sets a

          * the property value for the given property name and component instance

          * 

          * @param component

          *            - component instance to set property on

          * @param componentProperty

          *            - property name to set

          * @param idSuffix

          *            - suffix string to use for the generated component

          */

         protected void performConversion(Component component, String componentProperty, int idSuffix) {

                 // create new instance of replacement component

                 Component componentReplacement = ComponentUtils.copy(getComponentReplacementPrototype(), Integer.toString(idSuffix));

                 ObjectPropertyUtils.setPropertyValue(component, componentProperty, componentReplacement);

         }

         /**

          * @see org.kuali.rice.kns.uif.modifier.ComponentModifier#getSupportedComponents()

          */

         @Override

         public Set<Class<? extends Component>> getSupportedComponents() {

                 Set<Class<? extends Component>> components = new HashSet<Class<? extends Component>>();

                 components.add(Component.class);

                 return components;

         }

         /**

          * Type of component that should be replaced with an instance of the

          * component prototype

          * 

          * @return Class<? extends Component> component type to replace

          */

         public Class<? extends Component> getComponentTypeToReplace() {

                 return this.componentTypeToReplace;

         }

         /**

          * Setter for the component type to replace

          * 

          * @param componentTypeToReplace

          */

         public void setComponentTypeToReplace(Class<? extends Component> componentTypeToReplace) {

                 this.componentTypeToReplace = componentTypeToReplace;

         }

         /**

          * Prototype for the component replacement

          * 

          * <p>

          * Each time the type to replace if found a new instance of the component

          * prototype will be created and set as the new property value

          * </p>

          * 

          * @return

          */

         public Component getComponentReplacementPrototype() {

                 return this.componentReplacementPrototype;

         }

         /**

          * Setter for the replacement component prototype

          * 

          * @param componentReplacementPrototype

          */

         public void setComponentReplacementPrototype(Component componentReplacementPrototype) {

                 this.componentReplacementPrototype = componentReplacementPrototype;

         }

 }