/*
    * Ext GWT 2.2.5 - Ext for GWT
    * Copyright(c) 2007-2010, Ext JS, LLC.
    * licensing@extjs.com
    * 
    * http://extjs.com/license
    */
   package com.extjs.gxt.ui.client.widget.form;
   
  import java.util.List;
  
  import com.extjs.gxt.ui.client.core.El;
  import com.extjs.gxt.ui.client.core.XTemplate;
  import com.extjs.gxt.ui.client.data.ModelData;
  import com.extjs.gxt.ui.client.event.ComponentEvent;
  import com.extjs.gxt.ui.client.event.Events;
  import com.extjs.gxt.ui.client.event.Listener;
  import com.extjs.gxt.ui.client.event.SelectionChangedEvent;
  import com.extjs.gxt.ui.client.event.SelectionChangedListener;
  import com.extjs.gxt.ui.client.event.SelectionProvider;
  import com.extjs.gxt.ui.client.store.ListStore;
  import com.extjs.gxt.ui.client.util.Size;
  import com.extjs.gxt.ui.client.widget.ComponentHelper;
  import com.extjs.gxt.ui.client.widget.ListView;
  import com.google.gwt.dom.client.Document;
  import com.google.gwt.user.client.DOM;
  import com.google.gwt.user.client.Element;
  import com.google.gwt.user.client.Event;
  
  /**
   * A multi-select list field.
   * 
   * <dl>
   * <dt>Inherited Events:</dt>
   * <dd>Field Focus</dd>
   * <dd>Field Blur</dd>
   * <dd>Field Change</dd>
   * <dd>Field Invalid</dd>
   * <dd>Field Valid</dd>
   * <dd>Field KeyPress</dd>
   * <dd>Field SpecialKey</dd>
   * <dd>BoxComponent Move</dd>
   * <dd>BoxComponent Resize</dd>
   * <dd>Component Enable</dd>
   * <dd>Component Disable</dd>
   * <dd>Component BeforeHide</dd>
   * <dd>Component Hide</dd>
   * <dd>Component BeforeShow</dd>
   * <dd>Component Show</dd>
   * <dd>Component Attach</dd>
   * <dd>Component Detach</dd>
   * <dd>Component BeforeRender</dd>
   * <dd>Component Render</dd>
   * <dd>Component BrowserEvent</dd>
   * <dd>Component BeforeStateRestore</dd>
   * <dd>Component StateRestore</dd>
   * <dd>Component BeforeStateSave</dd>
   * <dd>Component SaveState</dd>
   * </dl>
   * 
   * @param <D> the model type
   */
  public class ListField<D extends ModelData> extends Field<D> implements SelectionProvider<D> {
  
    protected ListView<D> listView;
    protected ListStore<D> store;
  
    private XTemplate template;
    private String listStyle = "x-combo-list";
    private String selectedStyle = "x-combo-selected";
    private String itemSelector;
    private El input;
    private String valueField;
  
    public ListField() {
      listView = new ListView<D>();
      setSize(200, 100);
      setPropertyEditor(new ListModelPropertyEditor<D>());
    }
  
    public void addSelectionChangedListener(SelectionChangedListener<D> listener) {
      listView.getSelectionModel().addListener(Events.SelectionChange, listener);
    }
  
    @Override
    public void disable() {
      super.disable();
      listView.disable();
    }
  
    @Override
    public void enable() {
      super.enable();
      listView.enable();
    }
  
    /**
     * Returns the display field.
     * 
    * @return the display field
    */
   public String getDisplayField() {
     return getPropertyEditor().getDisplayProperty();
   }
 
   /**
    * Returns the item selector.
    * 
    * @return the item selector
    */
   public String getItemSelector() {
     return itemSelector;
   }
 
   /**
    * Returns the field's list view.
    * 
    * @return the list view
    */
   public ListView<D> getListView() {
     return listView;
   }
 
   @Override
   public ListModelPropertyEditor<D> getPropertyEditor() {
     return (ListModelPropertyEditor<D>) propertyEditor;
   }
 
   @Override
   public String getRawValue() {
     return "";
   }
 
   public List<D> getSelection() {
     return listView.getSelectionModel().getSelectedItems();
   }
 
   /**
    * Returns the field's store.
    * 
    * @return the store
    */
   public ListStore<D> getStore() {
     return store;
   }
 
   /**
    * Returns the custom template.
    * 
    * @return the template
    */
   public XTemplate getTemplate() {
     return template;
   }
 
   @Override
   public D getValue() {
     List<D> sel = getSelection();
     if (sel.size() > 0) {
       return sel.get(0);
     }
     return null;
   }
 
   public String getValueField() {
     return valueField;
   }
 
   public void removeSelectionListener(SelectionChangedListener<D> listener) {
     listView.getSelectionModel().removeListener(Events.SelectionChange, listener);
   }
 
   /**
    * Sets the display field.
    * 
    * @param displayField the display field
    */
   public void setDisplayField(String displayField) {
     getPropertyEditor().setDisplayProperty(displayField);
   }
 
   /**
    * This setting is required if a custom XTemplate has been specified.
    * 
    * @param itemSelector the item selector
    */
   public void setItemSelector(String itemSelector) {
     this.itemSelector = itemSelector;
   }
 
   @Override
   public void setPropertyEditor(PropertyEditor<D> propertyEditor) {
     assert propertyEditor instanceof ListModelPropertyEditor<?> : "PropertyEditor must be a ModelPropertyEditor instance";
     super.setPropertyEditor(propertyEditor);
   }
 
   public void setSelection(List<D> selection) {
     if (selection != null && selection.size() > 0) {
       super.setValue(selection.get(0));
       listView.getSelectionModel().setSelection(selection);
     } else {
       super.setValue(null);
       listView.getSelectionModel().deselectAll();
     }
   }
 
   @Override
   public void setValue(D value) {
     super.setValue(value);
     listView.getSelectionModel().select(value, false);
   }
 
   /**
    * Sets the list field's list store.
    * 
    * @param store the store
    */
   public void setStore(ListStore<D> store) {
     this.store = store;
   }
 
   /**
    * Sets the field's template used to render the list.
    * 
    * @param html the html frament
    */
   public void setTemplate(String html) {
     assertPreRender();
     template = XTemplate.create(html);
   }
 
   /**
    * Sets the field's template used to render the list.
    * 
    * @param template
    */
   public void setTemplate(XTemplate template) {
     assertPreRender();
     this.template = template;
   }
 
   /**
    * Sets the field's value field.
    * 
    * @param valueField the value field
    */
   public void setValueField(String valueField) {
     this.valueField = valueField;
   }
 
   @Override
   protected void doAttachChildren() {
     super.doAttachChildren();
     ComponentHelper.doAttach(listView);
   }
 
   @Override
   protected void doDetachChildren() {
     super.doDetachChildren();
     ComponentHelper.doDetach(listView);
   }
 
   @Override
   protected El getInputEl() {
     return input;
   }
 
   @Override
   protected void onFocus(ComponentEvent ce) {
     super.onFocus(ce);
     listView.focus();
   }
 
   @Override
   protected void onRender(Element parent, int index) {
     setElement(DOM.createDiv(), parent, index);
     addStyleName("x-form-list");
 
     input = new El((Element) Document.get().createHiddenInputElement().cast());
     getElement().appendChild(input.dom);
     if (template == null) {
       String html = "<tpl for=\".\"><div class='x-combo-list-item' role='option'>{" + getDisplayField() + "}</div></tpl>";
       template = XTemplate.create(html);
     }
     listView.setBorders(false);
     listView.setTemplate(template);
     listView.addStyleName(listStyle);
     listView.setItemSelector(itemSelector != null ? itemSelector : ".x-combo-list-item");
     listView.setStore(store);
 
     listView.setSelectStyle(selectedStyle);
     listView.setOverStyle("x-combo-over");
 
     listView.getSelectionModel().addListener(Events.SelectionChange, new Listener<SelectionChangedEvent<D>>() {
       public void handleEvent(SelectionChangedEvent<D> se) {
         onSelectionChange(se.getSelection());
       }
     });
 
     listView.render(getElement());
     listView.getAriaSupport().setRole("listbox");
     ComponentHelper.setParent(this, listView);
     disableTextSelection(true);
     sinkEvents(Event.ONCLICK);
 
     super.onRender(parent, index);
   }
 
   @Override
   protected void onResize(int width, int height) {
     super.onResize(width, height);
     Size frameWidth = el().getFrameSize();
     width -= frameWidth.width;
     height -= frameWidth.height;
     listView.setSize(width, height);
   }
 
   protected void onSelectionChange(List<D> sel) {
     String prop = valueField != null ? valueField : listView.getDisplayProperty();
     StringBuffer sb = new StringBuffer();
     for (D m : sel) {
       sb.append(m.get(prop).toString());
       sb.append(",");
     }
     String s = sb.toString();
     if (sb.length() > 1) {
       s = s.substring(0, s.length() - 1);
     }
     input.setValue(s);
   }
 
   @Override
   protected boolean validateValue(String value) {
     return true;
   }
 
 }