package org.kuali.student.common.ui.client.widgets.filter;

 import java.util.ArrayList;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.kuali.student.common.assembly.data.LookupMetadata;

 import org.kuali.student.common.search.dto.SearchRequest;

 import org.kuali.student.common.search.dto.SearchResult;

 import org.kuali.student.common.ui.client.application.KSAsyncCallback;

 import org.kuali.student.common.ui.client.service.SearchRpcService;

 import org.kuali.student.common.ui.client.service.SearchRpcServiceAsync;

 import org.kuali.student.common.ui.client.util.SearchUtils;

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

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

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

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

 import org.kuali.student.common.ui.client.widgets.field.layout.element.SpanPanel;

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

 import org.kuali.student.common.ui.client.widgets.list.SearchResultListItems;

 import org.kuali.student.common.ui.client.widgets.notification.LoadingDiv;

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

 import com.google.gwt.core.client.GWT;

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

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

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

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

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

 /**

  * This widget can be used to display a list of filter items with a list of options.

  * A selection of filter option will fire a filter select/deselect event which can 

  * be inspected to update a results widget to reflect the filter option selected.

  * 

  */

 public class KSFilterOptions extends Composite{

     private VerticalFlowPanel filterPanel = new VerticalFlowPanel();

     private VerticalFlowPanel filterTitlePanel = new VerticalFlowPanel();

     private KSLabel filterTitle = new KSLabel();

     private KSLabel filterDescription = new KSLabel();

     private VerticalFlowPanel filterContainer = new VerticalFlowPanel();

     private LoadingDiv loading = new LoadingDiv();

     List<KSFilterItem> filterItems = new ArrayList<KSFilterItem>();

     private int itemsIntializing = 0;

     private int itemsSelected = 0;

     private SearchRpcServiceAsync searchRpcService = GWT.create(SearchRpcService.class);

     public KSFilterOptions(List<LookupMetadata> lookups){

         filterTitlePanel.add(filterTitle);

         filterTitlePanel.add(filterDescription);

         filterContainer.add(filterTitlePanel);

         filterContainer.add(filterPanel);

         filterContainer.addStyleName("KS-Filter-Options-Parent-Container");

         filterTitlePanel.addStyleName("KS-Filter-Options-Title-Panel");

         filterTitle.addStyleName("KS-Filter-Options-Title-Label");

         filterTitle.addStyleName("KS-Indent" + "-1");

         filterDescription.addStyleName("KS-Basic-Menu-Desc-Label");

         filterDescription.addStyleName("KS-Indent" + "-1");

         filterDescription.addStyleName("KS-Indent" + "-1");

         KSButton resetButton = new KSButton("Reset", ButtonStyle.DEFAULT_ANCHOR);

         filterTitlePanel.add(resetButton);

         resetButton.addClickHandler(new ClickHandler(){

                         @Override

                         public void onClick(ClickEvent event) {

                                 for (KSFilterItem filterItem:filterItems){

                                         filterItem.reset();                                        

                                 }

                                 KSFilterOptions.this.fireEvent(new FilterResetEvent());

                                 itemsSelected = 0;

                         }                

         });

         init(lookups);

         this.initWidget(filterContainer);

     }

     protected void init(List<LookupMetadata> lookups){

             for (LookupMetadata lookup:lookups){

                     itemsIntializing ++;

                     KSFilterItem filterItem = new KSFilterItem(lookup);

                     filterPanel.add(filterItem);

             }            

     }

     /**

      * Add a filter event handler. A filter event gets fired anytime the user checks or unchecks a filter option.

      * A filter event will not get fired if an uncheck of filter item causes results in none of the checkboxes

      * being selected, instead filter reset event will get fired.

      * 

      * @param handler

      */

     public void addFilterEventHandler(FilterEventHandler handler){

             this.addHandler(handler, FilterEvent.TYPE);

     }

     /**

      * Add a reset handler. A reset event will get fired anytime all the filter checkboxes are not selected, either

      * via click of Reset or unchecking all checkboxes.

      * 

      * @param handler

      */

     public void addFilterResetEventHandler(FilterResetEventHandler handler){

             this.addHandler(handler, FilterResetEvent.TYPE);

     }

     private class KSFilterItem extends CollapsablePanel{

             SpanPanel itemContent;

             String itemKey;

             List<KSCheckBox> checkboxes = new ArrayList<KSCheckBox>();

             public KSFilterItem (final LookupMetadata lookup){

                     itemContent = new SpanPanel();

                     this.init(new KSLabel(lookup.getTitle()), itemContent, true, true, ImagePosition.ALIGN_LEFT);

                     this.addStyleName("KS-Filter-Item");

                     super.linkPanel.addStyleName("KS-Filter-Item-Label");

                     itemKey = lookup.getId();

                     SearchRequest sr = SearchUtils.initializeSearchRequest(lookup);

                     searchRpcService.search(sr, new KSAsyncCallback<SearchResult>(){

                                 @Override

                                 public void onSuccess(SearchResult result) {

                                         SearchResultListItems items = new SearchResultListItems(result.getRows(), lookup);

                                         for (String id:items.getItemIds()){

                                 final KSCheckBox checkbox = new KSCheckBox(items.getItemText(id));

                                 checkbox.setFormValue(id);

                                 checkboxes.add(checkbox);

                                 itemContent.add(checkbox);

                                 checkbox.addValueChangeHandler(new ValueChangeHandler<Boolean>(){

                                                         @Override

                                                         public void onValueChange(ValueChangeEvent<Boolean> event) {

                                                                 if (checkbox.getValue()){

                                                                         itemsSelected++;

                                                                 } else {

                                                                         itemsSelected--;

                                                                 }

                                                                 if (itemsSelected == 0){

                                                                         KSFilterOptions.this.fireEvent(new FilterResetEvent());

                                                                 } else {

                                                                         Map<String, List<String>> selectionMap = getSelectionMap();

                                                                         KSFilterOptions.this.fireEvent(new FilterEvent(selectionMap, checkbox.getValue(), itemsSelected == 1, itemKey, checkbox.getFormValue()));                                                                        

                                                                 }

                                                         }

                                 });

                             }

                                         itemsIntializing--;

                         filterItems.add(KSFilterItem.this);

                                 }

                     });                    

             }

             /**

              * Reset all checkboxes for this filter item.

              * 

              */

             public void reset(){

                         for (KSCheckBox checkbox:checkboxes){

                                 checkbox.setValue(false);

                         }

                 }

     }

     /**

      * Use to reset all filter checkboxes to unselected

      */

     public void reset(){

                 for (KSFilterItem filterItem:filterItems){

                         filterItem.reset();

                 }

                 itemsSelected = 0;

     }

     /** 

      * @return All the currently selected filter options

      */

     protected Map<String, List<String>> getSelectionMap(){

             Map<String, List<String>> selectionMap = new HashMap<String, List<String>>();

                 for (KSFilterItem filterItem:filterItems){

                         List<String> itemValues = new ArrayList<String>();

                         for (KSCheckBox itemCheckbox:filterItem.checkboxes){

                                 if (itemCheckbox.getValue()){

                                         itemValues.add(itemCheckbox.getFormValue());

                                 }

                         }

                         if (!itemValues.isEmpty()){

                                 selectionMap.put(filterItem.itemKey, itemValues);

                         }

                 }

                 return selectionMap;

     }

 }