/**
 * 
 */
package org.gcube.portlets.user.dataminermanager.client.form;

import java.util.ArrayList;

import org.gcube.portlets.user.dataminermanager.client.bean.parameters.ColumnParameter;
import org.gcube.portlets.user.dataminermanager.client.bean.parameters.Parameter;
import org.gcube.portlets.user.dataminermanager.client.properties.ColumnItemPropertiesCombo;
import org.gcube.portlets.user.dataminermanager.shared.data.ColumnItem;
import org.gcube.portlets.user.dataminermanager.shared.data.TableItemSimple;

import com.google.gwt.core.client.GWT;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.Widget;
import com.sencha.gxt.cell.core.client.form.ComboBoxCell.TriggerAction;
import com.sencha.gxt.data.shared.ListStore;
import com.sencha.gxt.widget.core.client.container.VerticalLayoutContainer;
import com.sencha.gxt.widget.core.client.form.ComboBox;

/**
 * 
 * @author Giancarlo Panichi email: <a
 *         href="mailto:g.panichi@isti.cnr.it">g.panichi@isti.cnr.it</a>
 *
 */
public class ColumnFld extends AbstractFld {

	private VerticalLayoutContainer vp;

	private String defaultColumn;

	private ComboBox<ColumnItem> comboBox;
	private ListStore<ColumnItem> store;
	private String referredTabularParameterName;

	/**
	 * @param parameter
	 */
	public ColumnFld(Parameter parameter) {
		super(parameter);
		vp = new VerticalLayoutContainer();

		ColumnParameter p = (ColumnParameter) parameter;
		this.referredTabularParameterName = p.getReferredTabularParameterName();
		this.defaultColumn = p.getDefaultColumn();

		ColumnItemPropertiesCombo props = GWT
				.create(ColumnItemPropertiesCombo.class);

		store = new ListStore<ColumnItem>(props.id());

		comboBox = new ComboBox<ColumnItem>(store, props.label());
		comboBox.setAllowBlank(false);
		comboBox.setForceSelection(true);
		comboBox.setEditable(false);
		comboBox.setTriggerAction(TriggerAction.ALL);
		if (p.getDescription() != null)
			comboBox.setTitle(p.getDescription());
		comboBox.setEnabled(false);
		showNoSelectionField();
	}

	/**
	 * 
	 */
	private void showNoSelectionField() {
		vp.clear();
		;
		vp.add(comboBox);
		vp.add(new HTML(
				"<div class='workflow-parameters-description'>Select table from parameter "
						+ referredTabularParameterName + "</div>"));
		vp.forceLayout();
	}

	/**
	 * 
	 */
	private void showFieldWithSelection(TableItemSimple tableItem) {
		vp.clear();
		vp.add(comboBox);
		vp.add(new HTML(
				"<div class='workflow-parameters-description'>Columns of Table "
						+ tableItem.getName() + "</div>"));
		vp.forceLayout();
	}

	/**
	 * 
	 */
	@Override
	public String getValue() {
		ColumnItem columnItem = comboBox.getCurrentValue();
		return columnItem != null ? columnItem.getName() : null;
	}

	/**
	 * 
	 */
	@Override
	public Widget getWidget() {
		return vp;
	}

	
	@Override
	public void fireEvent(Object message) {
		if (message == null) {
			store.clear();
			store.commitChanges();
			comboBox.clear();
			comboBox.setEnabled(false);
			showNoSelectionField();
		} else {
			TableItemSimple tableItem = (TableItemSimple) message;
			store.clear();
			store.commitChanges();
			ArrayList<ColumnItem> columns = tableItem.getColumns();
			if (columns != null) {
				store.addAll(columns);
				for (ColumnItem columnItem : columns) {
					if (columnItem.getName().compareTo(defaultColumn) == 0) {
						comboBox.setValue(columnItem);
						break;
					}
				}
				store.commitChanges();
			}
			comboBox.clear();
			comboBox.setEnabled(true);
			showFieldWithSelection(tableItem);
		}
	}

}