package org.vaadin.aceeditor.client;
   
   import java.util.LinkedList;
   import java.util.List;
   
   import com.google.gwt.core.client.GWT;
   import com.google.gwt.event.dom.client.ChangeEvent;
   import com.google.gwt.event.dom.client.ChangeHandler;
   import com.google.gwt.event.dom.client.DoubleClickEvent;
  import com.google.gwt.event.dom.client.DoubleClickHandler;
  import com.google.gwt.event.dom.client.KeyCodes;
  import com.google.gwt.event.dom.client.KeyDownEvent;
  import com.google.gwt.event.dom.client.KeyDownHandler;
  import com.google.gwt.user.client.Event;
  import com.google.gwt.user.client.ui.HTML;
  import com.google.gwt.user.client.ui.Image;
  import com.google.gwt.user.client.ui.ListBox;
  import com.vaadin.client.ui.VOverlay;
  
  public class SuggestPopup extends VOverlay implements KeyDownHandler,
  		DoubleClickHandler, ChangeHandler {
  	protected ListBox choiceList;
  
      protected String startOfValue = "";
  
  	public interface SuggestionSelectedListener {
  		void suggestionSelected(TransportSuggestion s);
  		void noSuggestionSelected();
  	}
  
      protected SuggestionSelectedListener listener;
  
      protected VOverlay descriptionPopup;
  
      protected List<TransportSuggestion> suggs;
      protected List<TransportSuggestion> visibleSuggs = new LinkedList<TransportSuggestion>();
  
      protected boolean showDescriptions = true;
  
      protected Image loadingImage;
  
  	public static final int WIDTH = 150;
  	public static final int HEIGHT = 200;
  
  	public static final int DESCRIPTION_WIDTH = 225;
  
  	// TODO addSuggestionSelectedListener?
  	public void setSuggestionSelectedListener(SuggestionSelectedListener ssl) {
  		listener = ssl;
  	}
  
  	public SuggestPopup() {
  		super(true);
  		setWidth(WIDTH + "px");
  		SuggestionResources resources = GWT.create(SuggestionResources.class);
  		loadingImage = new Image(resources.loading());
  		setWidget(loadingImage);
  	}
  	
  	protected void createChoiceList() {
  		choiceList = new ListBox();
  		choiceList.setStyleName("list");
  		choiceList.addKeyDownHandler(this);
  		choiceList.addDoubleClickHandler(this);
  		choiceList.addChangeHandler(this);
  		choiceList.setStylePrimaryName("aceeditor-suggestpopup-list");
  		setWidget(choiceList);
  	}
  	
  	protected void startLoading() {
  		if (descriptionPopup!=null) {
  			descriptionPopup.hide();
  		}
  		setWidget(loadingImage);
  	}
  	
  	public void setSuggestions(List<TransportSuggestion> suggs) {
  		this.suggs = suggs;
  		createChoiceList();
  		populateList();
  		if (choiceList.getItemCount() == 0) {
  			close();
  		}
  	}
  
      protected void populateList() {
  		choiceList.clear();
  		visibleSuggs.clear();
  		int i = 0;
  		for (TransportSuggestion s : suggs) {
  			if (s.suggestionText.toLowerCase().startsWith(startOfValue)) {
  				visibleSuggs.add(s);
  				choiceList.addItem(s.displayText, "" + i);
  			}
  			i++;
  		}
  		if (choiceList.getItemCount() > 0) {
  			int vic = Math.max(2, Math.min(10, choiceList.getItemCount()));
  			choiceList.setVisibleItemCount(vic);
 			choiceList.setSelectedIndex(0);
 			this.onChange(null);
 		}
 	}
 
 	public void close() {
 		hide();
 		if (listener != null)
 			listener.noSuggestionSelected();
 	}
 
 	@Override
 	public void hide() {
 		super.hide();
 		if (descriptionPopup != null)
 			descriptionPopup.hide();
 		descriptionPopup = null;
 	}
 
 	@Override
 	public void hide(boolean ac) {
 		super.hide(ac);
 		if (ac) {
 			// This happens when user clicks outside this popup (or something
 			// similar) while autohide is on. We must cancel the suggestion.
 			if (listener != null)
 				listener.noSuggestionSelected();
 		}
 		if (descriptionPopup != null)
 			descriptionPopup.hide();
 		descriptionPopup = null;
 	}
 
 	/* @Override */
 	public void onKeyDown(KeyDownEvent event) {
 		int keyCode = event.getNativeKeyCode();
 		if (keyCode == KeyCodes.KEY_ENTER
 				&& choiceList.getSelectedIndex() != -1) {
 			event.preventDefault();
 			event.stopPropagation();
 			select();
 		} else if (keyCode == KeyCodes.KEY_ESCAPE) {
 			event.preventDefault();
 			close();
 		}
 	}
 
 	/* @Override */
 	public void onDoubleClick(DoubleClickEvent event) {
 		event.preventDefault();
 		event.stopPropagation();
 		select();
 	}
 
 	@Override
 	public void onBrowserEvent(Event event) {
 		if (event.getTypeInt() == Event.ONCONTEXTMENU) {
 			event.stopPropagation();
 			event.preventDefault();
 			return;
 		}
 		super.onBrowserEvent(event);
 	}
 
 	public void up() {
 		if (suggs==null) {
 			return;
 		}
 		int current = this.choiceList.getSelectedIndex();
 		int next = (current - 1 >= 0) ? current - 1 : 0;
 		this.choiceList.setSelectedIndex(next);
 		// Note that setting the selection programmatically does not cause the
 		// ChangeHandler.onChange(ChangeEvent) event to be fired.
 		// Doing it manually.
 		this.onChange(null);
 	}
 
 	public void down() {
 		if (suggs==null) {
 			return;
 		}
 		int current = this.choiceList.getSelectedIndex();
 		int next = (current + 1 < choiceList.getItemCount()) ? current + 1
 				: current;
 		this.choiceList.setSelectedIndex(next);
 		// Note that setting the selection programmatically does not cause the
 		// ChangeHandler.onChange(ChangeEvent) event to be fired.
 		// Doing it manually.
 		this.onChange(null);
 	}
 
 	public void select() {
 		if (suggs==null) {
 			return;
 		}
 		
 		int selected = choiceList.getSelectedIndex();
 		if (listener != null) {
 			if (selected == -1) {
 				this.hide();
 				listener.noSuggestionSelected();
 			} else {
 				startLoading();
 				listener.suggestionSelected(visibleSuggs.get(selected));
 			}
 		}
 	}
 
 	@Override
 	public void onChange(ChangeEvent event) {
 		if (descriptionPopup == null) {
 			createDescriptionPopup();
 		}
 
 		int selected = choiceList.getSelectedIndex();
 		String descr = visibleSuggs.get(selected).descriptionText;
 
 		if (descr != null && !descr.isEmpty()) {
 			((HTML) descriptionPopup.getWidget()).setHTML(descr);
             if (showDescriptions) {
                 descriptionPopup.show();
             }
         } else {
 			descriptionPopup.hide();
 		}
 	}
 
 	@Override
 	public void setPopupPosition(int left, int top) {
 		super.setPopupPosition(left, top);
 		if (descriptionPopup!=null) {
 			updateDescriptionPopupPosition();
 		}
 	}
 	
 	protected void updateDescriptionPopupPosition() {
 		int x = getAbsoluteLeft() + WIDTH;
 		int y = getAbsoluteTop();
 		descriptionPopup.setPopupPosition(x, y);
 		if (descriptionPopup!=null) {
 			descriptionPopup.setPopupPosition(x, y);
 		}
 	}
 
 	protected void createDescriptionPopup() {
 		descriptionPopup = new VOverlay();
 		descriptionPopup.setOwner(getOwner());
 		descriptionPopup.setStylePrimaryName("aceeditor-suggestpopup-description");
 		HTML lbl = new HTML();
 		lbl.setWordWrap(true);
 		descriptionPopup.setWidget(lbl);
 		updateDescriptionPopupPosition();
 		descriptionPopup.setWidth(DESCRIPTION_WIDTH+"px");
 //		descriptionPopup.setSize(DESCRIPTION_WIDTH+"px", HEIGHT+"px");
 	}
 
 	public void setStartOfValue(String startOfValue) {
 		this.startOfValue = startOfValue.toLowerCase();
 		if (suggs==null) {
 			return;
 		}
 		populateList();
 		if (choiceList.getItemCount() == 0) {
 			close();
 		}
 	}
 
 }