/**

  * Copyright 2005-2011 The Kuali Foundation

  *

  * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.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.krad.uif.modifier;

 import org.apache.commons.lang.StringUtils;

 import org.apache.log4j.Logger;

 import org.kuali.rice.krad.service.KRADServiceLocatorWeb;

 import org.kuali.rice.krad.uif.UifConstants;

 import org.kuali.rice.krad.uif.UifPropertyPaths;

 import org.kuali.rice.krad.uif.container.Group;

 import org.kuali.rice.krad.uif.field.DataField;

 import org.kuali.rice.krad.uif.view.View;

 import org.kuali.rice.krad.uif.component.Component;

 import org.kuali.rice.krad.uif.field.HeaderField;

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

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

 import java.util.ArrayList;

 import java.util.HashMap;

 import java.util.HashSet;

 import java.util.List;

 import java.util.Map;

 import java.util.Set;

 /**

  * Generates <code>Field</code> instances to produce a comparison view among

  * objects of the same type

  *

  * <p>

  * Modifier is initialized with a List of <code>ComparableInfo</code> instances.

  * For each comparable info, a copy of the configured group field is made and

  * adjusted to the binding object path for the comparable. The comparison fields

  * are ordered based on the configured order property of the comparable. In

  * addition, a <code>HeaderField<code> can be generated to label each group

  * of comparison fields.

  * </p>

  *

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

  */

 public class CompareFieldCreateModifier extends ComponentModifierBase {

     private static final Logger LOG = Logger.getLogger(CompareFieldCreateModifier.class);

     private static final long serialVersionUID = -6285531580512330188L;

     private int defaultOrderSequence;

     private boolean generateCompareHeaders;

     private HeaderField headerFieldPrototype;

     private List<ComparableInfo> comparables;

     public CompareFieldCreateModifier() {

         defaultOrderSequence = 1;

         generateCompareHeaders = true;

         comparables = new ArrayList<ComparableInfo>();

     }

     /**

      * Calls <code>ViewHelperService</code> to initialize the header field prototype

      *

      * @see org.kuali.rice.krad.uif.modifier.ComponentModifier#performInitialization(org.kuali.rice.krad.uif.view.View,

      *      java.lang.Object, org.kuali.rice.krad.uif.component.Component)

      */

     @Override

     public void performInitialization(View view, Object model, Component component) {

         super.performInitialization(view, model, component);

         if (headerFieldPrototype != null) {

             view.getViewHelperService().performComponentInitialization(view, model, headerFieldPrototype);

         }

     }

     /**

      * Generates the comparison fields

      *

      * <p>

      * First the configured List of <code>ComparableInfo</code> instances are

      * sorted based on their order property. Then if generateCompareHeaders is

      * set to true, a <code>HeaderField</code> is created for each comparable

      * using the headerFieldPrototype and the headerText given by the

      * comparable. Finally for each field configured on the <code>Group</code>,

      * a corresponding comparison field is generated for each comparable and

      * adjusted to the binding object path given by the comparable in addition

      * to suffixing the id and setting the readOnly property

      * </p>

      *

      * @see org.kuali.rice.krad.uif.modifier.ComponentModifier#performModification(org.kuali.rice.krad.uif.view.View,

      *      java.lang.Object, org.kuali.rice.krad.uif.component.Component)

      */

     @SuppressWarnings("unchecked")

     @Override

     public void performModification(View view, Object model, Component component) {

         if ((component != null) && !(component instanceof Group)) {

             throw new IllegalArgumentException(

                     "Compare field initializer only support Group components, found type: " + component.getClass());

         }

         if (component == null) {

             return;

         }

         // list to hold the generated compare items

         List<Component> comparisonItems = new ArrayList<Component>();

         // sort comparables by their order property

         List<ComparableInfo> groupComparables = (List<ComparableInfo>) ComponentUtils.sort(comparables,

                 defaultOrderSequence);

         // evaluate expressions on comparables

         Map<String, Object> context = new HashMap<String, Object>();

         context.putAll(view.getContext());

         context.put(UifConstants.ContextVariableNames.COMPONENT, component);

         for (ComparableInfo comparable : groupComparables) {

             KRADServiceLocatorWeb.getExpressionEvaluatorService().evaluateObjectExpressions(comparable, model,

                     context);

         }

         // generate compare header

         if (isGenerateCompareHeaders()) {

             for (ComparableInfo comparable : groupComparables) {

                 HeaderField compareHeaderField = ComponentUtils.copy(headerFieldPrototype, comparable.getIdSuffix());

                 compareHeaderField.setHeaderText(comparable.getHeaderText());

                 comparisonItems.add(compareHeaderField);

             }

         }

         // find the comparable to use for comparing value changes (if

         // configured)

         boolean performValueChangeComparison = false;

         String compareValueObjectBindingPath = null;

         for (ComparableInfo comparable : groupComparables) {

             if (comparable.isCompareToForValueChange()) {

                 performValueChangeComparison = true;

                 compareValueObjectBindingPath = comparable.getBindingObjectPath();

             }

         }

         // generate the compare items from the configured group

         Group group = (Group) component;

         for (Component item : group.getItems()) {

             int defaultSuffix = 0;

             for (ComparableInfo comparable : groupComparables) {

                 String idSuffix = comparable.getIdSuffix();

                 if (StringUtils.isBlank(idSuffix)) {

                     idSuffix = UifConstants.IdSuffixes.COMPARE + defaultSuffix;

                 }

                 Component compareItem = ComponentUtils.copy(item, idSuffix);

                 ComponentUtils.setComponentPropertyDeep(compareItem, UifPropertyPaths.BIND_OBJECT_PATH,

                         comparable.getBindingObjectPath());

                 if (comparable.isReadOnly()) {

                     compareItem.setReadOnly(true);

                     if (compareItem.getPropertyExpressions().containsKey("readOnly")) {

                         compareItem.getPropertyExpressions().remove("readOnly");

                     }

                 }

                 // do value comparison

                 if (performValueChangeComparison && comparable.isHighlightValueChange() && !comparable

                         .isCompareToForValueChange()) {

                     performValueComparison(group, compareItem, model, compareValueObjectBindingPath);

                 }

                 comparisonItems.add(compareItem);

                 defaultSuffix++;

             }

         }

         // update the group's list of components

         group.setItems(comparisonItems);

     }

     /**

      * For each attribute field in the compare item, retrieves the field value and compares against the value for the

      * main comparable. If the value is different, adds script to the field on ready event to add the change icon to

      * the field and the containing group header

      *

      * @param group - group that contains the item and whose header will be highlighted for changes

      * @param compareItem - the compare item being generated and to pull attribute fields from

      * @param model - object containing the data

      * @param compareValueObjectBindingPath - object path for the comparison item

      */

     protected void performValueComparison(Group group, Component compareItem, Object model,

             String compareValueObjectBindingPath) {

         // get any attribute fields for the item so we can compare the values

         List<DataField> itemFields = ComponentUtils.getComponentsOfTypeDeep(compareItem, DataField.class);

         for (DataField field : itemFields) {

             String fieldBindingPath = field.getBindingInfo().getBindingPath();

             Object fieldValue = ObjectPropertyUtils.getPropertyValue(model, fieldBindingPath);

             String compareBindingPath = StringUtils.replaceOnce(fieldBindingPath,

                     field.getBindingInfo().getBindingObjectPath(), compareValueObjectBindingPath);

             Object compareValue = ObjectPropertyUtils.getPropertyValue(model, compareBindingPath);

             boolean valueChanged = false;

             if (!((fieldValue == null) && (compareValue == null))) {

                 // if one is null then value changed

                 if ((fieldValue == null) || (compareValue == null)) {

                     valueChanged = true;

                 } else {

                     // both not null, compare values

                     valueChanged = !fieldValue.equals(compareValue);

                 }

             }

             // add script to show change icon

             if (valueChanged) {

                 String onReadyScript = "showChangeIcon('" + field.getId() + "');";

                 // add icon to group header

                 Component headerField = group.getHeader();

                 onReadyScript += "showChangeIconOnHeader('" + headerField.getId() + "');";

                 field.setOnDocumentReadyScript(onReadyScript);

             }

             // TODO: add script for value changed?

         }

     }

     /**

      * Generates an id suffix for the comparable item

      *

      * <p>

      * If the idSuffix to use if configured on the <code>ComparableInfo</code>

      * it will be used, else the given integer index will be used with an

      * underscore

      * </p>

      *

      * @param comparable - comparable info to check for id suffix

      * @param index - sequence integer

      * @return String id suffix

      * @see org.kuali.rice.krad.uif.modifier.ComparableInfo.getIdSuffix()

      */

     protected String getIdSuffix(ComparableInfo comparable, int index) {

         String idSuffix = comparable.getIdSuffix();

         if (StringUtils.isBlank(idSuffix)) {

             idSuffix = "_" + index;

         }

         return idSuffix;

     }

     /**

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

      */

     @Override

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

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

         components.add(Group.class);

         return components;

     }

     /**

      * @see org.kuali.rice.krad.uif.modifier.ComponentModifierBase#getComponentPrototypes()

      */

     public List<Component> getComponentPrototypes() {

         List<Component> components = new ArrayList<Component>();

         components.add(headerFieldPrototype);

         return components;

     }

     /**

      * Indicates the starting integer sequence value to use for

      * <code>ComparableInfo</code> instances that do not have the order property

      * set

      *

      * @return int default sequence starting value

      */

     public int getDefaultOrderSequence() {

         return this.defaultOrderSequence;

     }

     /**

      * Setter for the default sequence starting value

      *

      * @param defaultOrderSequence

      */

     public void setDefaultOrderSequence(int defaultOrderSequence) {

         this.defaultOrderSequence = defaultOrderSequence;

     }

     /**

      * Indicates whether a <code>HeaderField</code> should be created for each

      * group of comparison fields

      *

      * <p>

      * If set to true, for each group of comparison fields a header field will

      * be created using the headerFieldPrototype configured on the modifier with

      * the headerText property of the comparable

      * </p>

      *

      * @return boolean true if the headers should be created, false if no

      *         headers should be created

      */

     public boolean isGenerateCompareHeaders() {

         return this.generateCompareHeaders;

     }

     /**

      * Setter for the generate comparison headers indicator

      *

      * @param generateCompareHeaders

      */

     public void setGenerateCompareHeaders(boolean generateCompareHeaders) {

         this.generateCompareHeaders = generateCompareHeaders;

     }

     /**

      * Prototype instance to use for creating the <code>HeaderField</code> for

      * each group of comparison fields (if generateCompareHeaders is true)

      *

      * @return HeaderField header field prototype

      */

     public HeaderField getHeaderFieldPrototype() {

         return this.headerFieldPrototype;

     }

     /**

      * Setter for the header field prototype

      *

      * @param headerFieldPrototype

      */

     public void setHeaderFieldPrototype(HeaderField headerFieldPrototype) {

         this.headerFieldPrototype = headerFieldPrototype;

     }

     /**

      * List of <code>ComparableInfo</code> instances the compare fields should

      * be generated for

      *

      * <p>

      * For each comparable, a copy of the fields configured for the

      * <code>Group</code> will be created for the comparison view

      * </p>

      *

      * @return List<ComparableInfo> comparables to generate fields for

      */

     public List<ComparableInfo> getComparables() {

         return this.comparables;

     }

     /**

      * Setter for the list of comparable info instances

      *

      * @param comparables

      */

     public void setComparables(List<ComparableInfo> comparables) {

         this.comparables = comparables;

     }

 }