/*--------------------------------------------------------------------------
    *  Copyright 2007 utgenome.org
    *
    *  Licensed under the Apache 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.apache.org/licenses/LICENSE-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.
   *--------------------------------------------------------------------------*/
  //--------------------------------------
  // GenomeBrowser Project
  //
  // ValueSelectorTrack.java
  // Since: Jun 13, 2007
  //
  // $URL$ 
  // $Author$
  //--------------------------------------
  package org.utgenome.gwt.utgb.client.track.lib;
  
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  
  import org.utgenome.gwt.utgb.client.track.Track;
  import org.utgenome.gwt.utgb.client.track.TrackBase;
  import org.utgenome.gwt.utgb.client.track.TrackFrame;
  import org.utgenome.gwt.utgb.client.track.TrackGroup;
  import org.utgenome.gwt.utgb.client.track.TrackGroupPropertyChange;
  import org.utgenome.gwt.utgb.client.util.CanonicalProperties;
  import org.utgenome.gwt.utgb.client.util.JSONUtil;
  
  import com.google.gwt.event.dom.client.ClickEvent;
  import com.google.gwt.event.dom.client.ClickHandler;
  import com.google.gwt.user.client.ui.Anchor;
  import com.google.gwt.user.client.ui.FlowPanel;
  import com.google.gwt.user.client.ui.Widget;
  
  /**
   * {@link ValueSelectorTrack} displays a set of text values. When you click one of these values, its corresponding track
   * property will be changed, then a {@link Track#onChangeTrackGroupProperty(TrackGroupPropertyChange)} event is
   * broadcasted to all tracks in a group.
   * 
   * @author leo
   * 
   */
  public class ValueSelectorTrack extends TrackBase {
  	public static TrackFactory factory() {
  		return new TrackFactory() {
  			private String trackName;
  			private String targetProperty;
  			private List<String> linkList = new ArrayList<String>();
  
  			public Track newInstance() {
  				final ValueSelectorTrack track = new ValueSelectorTrack(trackName, targetProperty);
  
  				final int SIZE = linkList.size();
  				for (int i = 0; i < SIZE; i++) {
  					final String value = (linkList.get(i));
  					track.addValue(value);
  				}
  
  				return track;
  			}
  
  			public void setProperty(String key, String value) {
  				if (key.equals("trackName"))
  					trackName = value;
  				else if (key.equals("targetProperty"))
  					targetProperty = value;
  				else if (key.equals("value")) {
  					linkList.add(value);
  				}
  			}
  
  			public void clear() {
  				linkList.clear();
  			}
  
  		};
  	}
  
  	private String _targetProperty;
  	private String _selectedValue;
  
  	private FlowPanel _linkPanel = new FlowPanel();
  	private ArrayList<ValueLink> _linkList = new ArrayList<ValueLink>();
  
  	class ValueLink extends Anchor implements ClickHandler {
  		public ValueLink(String value) {
  			super(value, value);
  			setStyleName("selector-item");
  			addClickHandler(this);
 		}
 
 		public void onClick(ClickEvent e) {
 			getTrackGroup().getPropertyWriter().setProperty(_targetProperty, getText());
 
 			setSelectionStyle(this);
 		}
 
 		public String toString() {
 			return this.getText();
 		}
 	}
 
 	public String getTargetProperty() {
 		return _targetProperty;
 	}
 
 	private void setSelectionStyle(ValueLink link) {
 		if (link == null)
 			return;
 
 		_selectedValue = link.toString();
 		link.setStyleName("selector-item-selected");
 		for (Iterator<ValueLink> it = _linkList.iterator(); it.hasNext();) {
 			ValueLink v = it.next();
 			if (v != link)
 				v.setStyleName("selector-item");
 		}
 	}
 
 	private ValueLink search(String value) {
 		for (Iterator<ValueLink> it = _linkList.iterator(); it.hasNext();) {
 			ValueLink v = it.next();
 			if (v.getText().equals(value))
 				return v;
 		}
 		return null;
 	}
 
 	public ValueSelectorTrack(String trackName, String targetProperty) {
 		super(trackName);
 		_linkPanel.setHeight("15px");
 		_linkPanel.setWidth("100%");
 		this._targetProperty = targetProperty;
 	}
 
 	public void addValue(String value) {
 		_linkList.add(new ValueLink(value));
 	}
 
 	public void clearValues() {
 		_linkList.clear();
 	}
 
 	public void clear() {
 		_linkPanel.clear();
 	}
 
 	public int getDefaultWindowHeight() {
 		return 15;
 	}
 
 	public Widget getWidget() {
 		return _linkPanel;
 	}
 
 	protected void updateSelection() {
 		setSelectionStyle(search(_selectedValue));
 	}
 
 	public void onChangeTrackGroupProperty(TrackGroupPropertyChange change) {
 		if (change.contains(_targetProperty)) {
 			_selectedValue = change.getProperty(_targetProperty);
 			updateSelection();
 		}
 
 	}
 
 	public void draw() {
 		_linkPanel.clear();
 		for (Iterator<ValueLink> it = _linkList.iterator(); it.hasNext();) {
 			ValueLink link = it.next();
 			_linkPanel.add(link);
 		}
 		updateSelection();
 	}
 
 	public void setUp(TrackFrame trackFrame, TrackGroup group) {
 		trackFrame.pack();
 	}
 
 	public void saveProperties(CanonicalProperties saveData) {
 		saveData.add("targetProperty", _targetProperty);
 		saveData.add("valueList", JSONUtil.toJSONArray(_linkList));
 		saveData.add("selectedValue", _selectedValue);
 	}
 
 	public void restoreProperties(CanonicalProperties properties) {
 		_targetProperty = properties.get("targetProperty", _targetProperty);
 		_selectedValue = properties.get("selectedValue", _selectedValue);
 		ArrayList<String> valueList = JSONUtil.parseJSONArray(properties.get("valueList", "[]"));
 		_linkList.clear();
 		for (String value : valueList) {
 			addValue(value);
 		}
 	}
 
 }