/**

  * Copyright 2010 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.osedu.org/licenses/ECL-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.kuali.student.common.ui.client.widgets.list;

 import java.util.ArrayList;

 import java.util.Iterator;

 import java.util.List;

 import java.util.Map;

 import java.util.Map.Entry;

 import org.kuali.student.common.ui.client.configurable.mvc.WidgetConfigInfo;

 import org.kuali.student.common.ui.client.mvc.Callback;

 import org.kuali.student.common.ui.client.mvc.HasDataValue;

 import org.kuali.student.common.ui.client.mvc.HasWidgetReadyCallback;

 import org.kuali.student.common.ui.client.mvc.TranslatableValueWidget;

 import org.kuali.student.common.ui.client.widgets.DataHelper;

 import org.kuali.student.common.ui.client.widgets.HasInputWidget;

 import org.kuali.student.common.ui.client.widgets.KSButton;

 import org.kuali.student.common.ui.client.widgets.KSItemLabel;

 import org.kuali.student.common.ui.client.widgets.KSButtonAbstract.ButtonStyle;

 import org.kuali.student.common.ui.client.widgets.layout.VerticalFlowPanel;

 import org.kuali.student.common.ui.client.widgets.menus.KSListPanel;

 import org.kuali.student.common.ui.client.widgets.menus.KSListPanel.ListType;

 import org.kuali.student.common.ui.client.widgets.search.KSPicker;

 import org.kuali.student.common.ui.client.widgets.search.SelectedResults;

 import org.kuali.student.common.ui.client.widgets.suggestbox.KSSuggestBox;

 import org.kuali.student.core.assembly.data.Data;

 import org.kuali.student.core.assembly.data.Data.DataValue;

 import org.kuali.student.core.assembly.data.Data.Property;

 import org.kuali.student.core.assembly.data.Data.StringKey;

 import org.kuali.student.core.assembly.data.Data.Value;

 import com.google.gwt.event.dom.client.ClickEvent;

 import com.google.gwt.event.dom.client.ClickHandler;

 import com.google.gwt.event.logical.shared.CloseEvent;

 import com.google.gwt.event.logical.shared.CloseHandler;

 import com.google.gwt.event.shared.HandlerRegistration;

 import com.google.gwt.user.client.Timer;

 import com.google.gwt.user.client.ui.Composite;

 import com.google.gwt.user.client.ui.HasName;

 import com.google.gwt.user.client.ui.HorizontalPanel;

 import com.google.gwt.user.client.ui.Widget;

 public class KSSelectedList extends Composite implements HasDataValue, HasName, HasSelectionChangeHandlers, HasWidgetReadyCallback, TranslatableValueWidget, HasInputWidget {

     private static final String VALUE = "value";

     private static final String DISPLAY = "display";

     private String name;

     private boolean initialized;

     private VerticalFlowPanel mainPanel;

     private HorizontalPanel pickerPanel;

     private KSPicker picker;

     private KSButton addItemButton;

     private KSListPanel valuesPanel;

 //    private List<SelectedValue> selectedValues = new ArrayList<SelectedValue>();

 //    private List<SelectedValue> removedValues = new ArrayList<SelectedValue>();

     private List<KSItemLabel> selectedItems = new ArrayList<KSItemLabel>();

     private List<KSItemLabel> removedItems = new ArrayList<KSItemLabel>();

     public static ItemDataHelper itemDataHelper = new ItemDataHelper();

     private final List<SelectionChangeHandler> selectionChangeHandlers = new ArrayList<SelectionChangeHandler>();

     private final List<Callback<Widget>> widgetReadyCallbacks = new ArrayList<Callback<Widget>>();

     private boolean hasDetails = false;

     private WidgetConfigInfo config;

     public KSSelectedList(WidgetConfigInfo config, boolean hasDetails) {

         init(config, hasDetails);

     }

     public KSSelectedList(WidgetConfigInfo config) {

         init(config, false);

     }

     public WidgetConfigInfo getConfig() {

         return config;

     }

     private void init(WidgetConfigInfo config, final boolean hasDetails) {

         this.config = config;

         this.hasDetails = hasDetails;

         mainPanel = new VerticalFlowPanel();

         initWidget(mainPanel);

         if (config.canEdit) {

             pickerPanel = new HorizontalPanel();

             pickerPanel.addStyleName("ks-selected-list-picker");

             addItemButton = new KSButton("Add to list", ButtonStyle.SECONDARY_SMALL);

             addItemButton.setEnabled(false);

             picker = new KSPicker(config);

             picker.setAdvancedSearchCallback(createAdvancedSearchCallback());

             addSelectionChangeHandler();

             addItemButton.addClickHandler(new ClickHandler() {

                 @Override

                 public void onClick(ClickEvent event) {

                     DataValue v = (DataValue) picker.getValue();

                     Data d = v.get();

                     Iterator<Property> iter = d.realPropertyIterator();

                     while (iter.hasNext()) {

                         Property p = iter.next();

                         String s = p.getValue();

                         KSItemLabel selectedItem = createItem(s, picker.getDisplayValue(), 

                                 hasDetails);

                         addItem(selectedItem);

                     }

                     picker.clear();

                     addItemButton.setEnabled(false);

                 }

             });

             pickerPanel.add(picker);

             pickerPanel.add(addItemButton);

             mainPanel.add(pickerPanel);

         }

         valuesPanel = new KSListPanel(ListType.UNORDERED);

         if(config.canEdit){

             valuesPanel.setStyleName("ks-selected-list");

         }

         else{

             valuesPanel.setStyleName("ks-selected-list-readOnly");

         }

         mainPanel.add(valuesPanel);

         initialized = true;

         widgetReady();

     }

     public KSListPanel separateValuesPanel() {

         mainPanel.remove(valuesPanel);

         return valuesPanel;

     }

     private void widgetReady() {

         for (Callback<Widget> callback : widgetReadyCallbacks) {

             callback.exec(this);

         }

     }

     private Callback<List<SelectedResults>> createAdvancedSearchCallback() {

         Callback<List<SelectedResults>> result = new Callback<List<SelectedResults>>() {

             public void exec(List<SelectedResults> results) {

                 if (results.size() > 0) {

                     for (SelectedResults res : results) {

                         KSItemLabel item = createItem(res.getReturnKey(), res.getDisplayKey(), hasDetails);

                         addItem(item, false);

                     }

                     picker.clear();

                     addItemButton.setEnabled(false);

                     selectionChanged();

                 }

             }

         };

         return result;

     }

     /**

      * Adds handler when suggest box selection change event is fired and enables/disables the the

      * Add item button accordingly. 

      */

     private void addSelectionChangeHandler() {

         if (picker.getInputWidget() instanceof KSSuggestBox){

                 KSSuggestBox suggestBox = (KSSuggestBox)picker.getInputWidget();

                 suggestBox.addSelectionChangeHandler(new SelectionChangeHandler(){

                                 @Override

                                 public void onSelectionChange(SelectionChangeEvent event) {

                                         //Compare the user entered value in picker's input textbox with the current display value

                                         //from the picker suggest list, if they are the same (ie. user has selected item from list)

                                         //then enable the add to list button. NOTE: This comparison should not be required if the picker

                                         //ONLY fired selection change event when an actual selection change took place, but doesn't seem

                                         //to be doing that.

                                         String userValue = ((KSSuggestBox)picker.getInputWidget()).getText();

                         String displayValue = picker.getDisplayValue();

                         boolean enabled = displayValue != null && !displayValue.isEmpty() && displayValue.equals(userValue);

                     addItemButton.setEnabled(enabled);

                                 }

                 });

         }

     }

     public void addItem(final KSItemLabel item) {

         addItem(item, true);

     }

     public void addItem(final KSItemLabel item, boolean fireChangeListeners) {

         if (removedItems.contains(item)) {

             removedItems.remove(item);

         }

         if (!selectedItems.contains(item)) {

             selectedItems.add(item);

         }

         valuesPanel.add(item);

         if (fireChangeListeners) {

             selectionChanged();

         }

         if (config.canEdit && fireChangeListeners) {

             item.setHighlighted(true);

             new Timer() {

                 @Override

                 public void run() {

                     item.setHighlighted(false);

                 }

             }.schedule(5000);

         } else {

             item.removeHighlight();

         }

     }

     private void selectionChanged() {

         for (SelectionChangeHandler handler : selectionChangeHandlers) {

             handler.onSelectionChange(new SelectionChangeEvent(this));

         }

     }

     public void clear() {

         selectedItems = new ArrayList<KSItemLabel>();

         removedItems = new ArrayList<KSItemLabel>();

         valuesPanel.clear();

     }

     @Override

     public String getName() {

         return name;

     }

     @Override

     public void setName(String name) {

         this.name = name;

     }

     @Override

     public HandlerRegistration addSelectionChangeHandler(final SelectionChangeHandler handler) {

         selectionChangeHandlers.add(handler);

         HandlerRegistration result = new HandlerRegistration() {

             @Override

             public void removeHandler() {

                 selectionChangeHandlers.remove(handler);

             }

         };

         return result;

     }

     @Override

     public void addWidgetReadyCallback(Callback<Widget> callback) {

         widgetReadyCallbacks.add(callback);

     }

     @Override

     public boolean isInitialized() {

         return initialized;

     }

     @Override

     public void setInitialized(boolean initialized) {

         this.initialized = initialized;

     }

     @Override

     public void addValueChangeCallback(Callback<Value> callback) {

         // TODO ryan - THIS METHOD NEEDS JAVADOCS

     }

     @Override

     public Value getValue() {

         Data data = new Data();

         for (KSItemLabel item : selectedItems) {

             data.add(item.getKey());

         }

         DataValue result = new DataValue(data);

         return result;

     }

     public List<KSItemLabel> getSelectedItems() {

         return selectedItems;

     }

     /**

      * Returns all selected values along with their translations in the _runtime data.

      *

      * @return

      */

     public Value getValueWithTranslations() {

         Data data = new Data();

         Data _runtimeData = new Data();

         for (KSItemLabel item : selectedItems) {

             data.add(item.getKey());

             Data displayData = new Data();

             displayData.set("id-translation", item.getDisplayText());

             _runtimeData.add(displayData);

         }

         data.set(new StringKey("_runtimeData"), _runtimeData);

         DataValue result = new DataValue(data);

         return result;

     }

     private KSItemLabel createItem(String value, String display, boolean hasDetails) {

         Data itemData = toItemData(value, display);

         DataValue itemDataValue = new DataValue(itemData);

         KSItemLabel item = new KSItemLabel(KSSelectedList.this.config.canEdit, hasDetails,

                 itemDataHelper);

         item.setValue(itemDataValue);

         item.addCloseHandler(new CloseHandler<KSItemLabel>() {

             @Override

             public void onClose(CloseEvent<KSItemLabel> event) {

                 KSItemLabel itemToBeDeleted = event.getTarget();

                 selectedItems.remove(itemToBeDeleted);

                 removedItems.add(itemToBeDeleted);

                 valuesPanel.remove(itemToBeDeleted);

                 selectionChanged();

             }

         });

         return item;

     }

     private Data toItemData(String value, String display) {

         Data data = new Data();

         data.set(VALUE, value);

         data.set(DISPLAY, display);

         return data;

     }

     @Override

     public void setValue(Value value) {

         clear();

         if (value != null) {

             Data data = ((DataValue) value).get();

             Iterator<Property> iter = data.realPropertyIterator();

             while (iter.hasNext()) {

                 Property p = iter.next();

                 String v = (String) p.getValue();

                 //FIXME: do we need to do a search? is this method ever going to be called?

                 KSItemLabel item = createItem(v, "Display: " + v, hasDetails);

                 addItem(item);

             }

         }

     }

     public static class ItemDataHelper implements DataHelper {

         @Override

         public String parse(Data data) {

             String result;

             if (data == null) {

                 return null;

             }

             result = (String) data.get(DISPLAY);

             return result;

         }

         @Override

         public String getKey(Data data) {

             String result;

             if (data == null) {

                 return null;

             }

             result = (String) data.get(VALUE);

             return result;

         }

     }

     @Override

     public void setValue(String id, String translation) {

         clear();

         if (id != null && translation != null) {

             addItem(createItem(id, translation, hasDetails), false);

         }

     }

     @Override

     public void setValue(Map<String, String> translations) {

         clear();

         if (translations != null) {

             for (Entry<String, String> e : translations.entrySet()) {

                 addItem(createItem(e.getKey(), e.getValue(), hasDetails), false);

             }

         }

     }

     @Override

     public Widget getInputWidget() {

         if (picker == null) {

             return valuesPanel;

         }

         return picker.getInputWidget();

     }

 }