EDIT

/**

 * 

 */

package eu.etaxonomy.taxeditor.ui.term;

import java.util.ArrayList;

import java.util.Collections;

import java.util.Comparator;

import java.util.List;

import org.eclipse.jface.util.PropertyChangeEvent;

import org.eclipse.swt.SWT;

import org.eclipse.swt.events.DisposeEvent;

import org.eclipse.swt.events.DisposeListener;

import org.eclipse.swt.events.SelectionEvent;

import org.eclipse.swt.events.SelectionListener;

import org.eclipse.swt.graphics.Color;

import org.eclipse.swt.widgets.Combo;

import org.eclipse.swt.widgets.Composite;

import org.eclipse.swt.widgets.Label;

import org.eclipse.swt.widgets.Listener;

import eu.etaxonomy.cdm.model.common.DefinedTermBase;

import eu.etaxonomy.taxeditor.preference.PreferencesUtil;

import eu.etaxonomy.taxeditor.preference.Resources;

import eu.etaxonomy.taxeditor.store.CdmStore;

import eu.etaxonomy.taxeditor.store.StoreUtil;

import eu.etaxonomy.taxeditor.store.TermManager;

import eu.etaxonomy.taxeditor.ui.forms.AbstractCdmFormElement;

import eu.etaxonomy.taxeditor.ui.forms.CdmFormFactory;

import eu.etaxonomy.taxeditor.ui.forms.CdmPropertyChangeEvent;

import eu.etaxonomy.taxeditor.ui.forms.ICdmFormElement;

import eu.etaxonomy.taxeditor.ui.forms.IEnableableFormElement;

import eu.etaxonomy.taxeditor.ui.forms.ISelectable;

/**

 * <p>

 * Abstract AbstractTermComboElement class.

 * </p>

 * 

 * @author n.hoffmann

 * @created Nov 5, 2009

 * @version 1.0

 * @param <T>

 */

public abstract class AbstractTermComboElement<T extends DefinedTermBase>

		extends AbstractCdmFormElement implements SelectionListener,

		DisposeListener, IEnableableFormElement, ISelectable {

	T selection;

	private static String EMPTY_ELEMENT_LABEL = "";

	T emptyElement;

	protected Label label;

	private Combo combo;

	private ArrayList<T> terms;

	private Comparator<T> termComparator;

	private Composite msgComposite;

	/**

	 * <p>

	 * Constructor for AbstractTermComboElement.

	 * </p>

	 * 

	 * @param parentElement

	 *            a {@link eu.etaxonomy.taxeditor.ui.forms.ICdmFormElement}

	 *            object.

	 * @param style

	 *            a int.

	 * @param formFactory

	 *            a {@link eu.etaxonomy.taxeditor.ui.forms.CdmFormFactory}

	 *            object.

	 * @param labelString

	 *            a {@link java.lang.String} object.

	 * @param selection

	 *            a T object.

	 * @param visibleItems

	 *            a int.

	 * @param <T>

	 *            a T object.

	 */

	public AbstractTermComboElement(CdmFormFactory formFactory,

			ICdmFormElement parentElement, String labelString, T selection,

			int visibleItems, int style) {

		super(formFactory, parentElement);

		if (labelString != null) {

			label = formFactory.createLabel(getLayoutComposite(), labelString);

			addControl(label);

		}

		// create combo

		combo = new Combo(getLayoutComposite(), SWT.BORDER | SWT.READ_ONLY);

		addControl(combo);

		combo.setLayoutData(CdmFormFactory.FILL_HORIZONTALLY());

		combo.setVisibleItemCount(visibleItems);

		populateTerms(preferredTerms());

		combo.addSelectionListener(this);

		combo.addDisposeListener(this);

		PreferencesUtil.getPreferenceStore().addPropertyChangeListener(this);

		if (selection != null) {

			setSelection(selection);

		}

	}

	/**

	 * <p>

	 * Getter for the field <code>selection</code>.

	 * </p>

	 * 

	 * @return a T object.

	 */

	public T getSelection() {

		return selection;

	}

	/**

	 * <p>

	 * Setter for the field <code>selection</code>.

	 * </p>

	 * 

	 * @param selection

	 *            a T object.

	 */

	public void setSelection(T selection) {

		Listener[] listeners = combo.getListeners(SWT.Selection);

		for (Listener listener : listeners) {

			combo.removeListener(SWT.Selection, listener);

		}

		int index = terms.indexOf(selection);

		if (index == -1) {

			createTermNotInPreferredTerms(selection);

			index = terms.indexOf(selection);

		}

		combo.select(index);

		for (Listener listener : listeners) {

			combo.addListener(SWT.Selection, listener);

		}

	}

	private void populateTerms(List<T> preferredTerms) {

		combo.removeAll();

		terms = new ArrayList<T>();

		int i = 1;

		int index = 0;

		// Add an empty element for when nothing was selected yet

		combo.add(EMPTY_ELEMENT_LABEL);

		terms.add(emptyElement);

		if (termComparator != null) {

			Collections.sort(preferredTerms, termComparator);

		}

		for (T term : preferredTerms) {

			String label = getLabel(term);

			if (label == null) {

				if (term.getTitleCache() != null) {

					label = term.getTitleCache();

					StoreUtil.error(getClass(),

							"Term does not have a representation: " + term

									+ ", " + term.getUuid(), null);

				} else {

					label = "Unknown";

					StoreUtil.error(getClass(),

							"Representation Label and TitleCache empty for term: "

									+ term + ", " + term.getUuid(), null);

				}

			}

			combo.add(label);

			terms.add(term);

			i++;

			if (selection != null) {

				if (selection.equals(term)) {

					index = i;

				}

			}

		}

		if (selection != null && index == 0) {

			createTermNotInPreferredTerms(selection);

		}

		combo.select(index);

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see

	 * eu.etaxonomy.taxeditor.forms.IEnableableFormElement#setEnabled(boolean)

	 */

	/** {@inheritDoc} */

	public void setEnabled(boolean enabled) {

		combo.setEnabled(enabled);

	}

	/**

	 * <p>

	 * preferredTerms

	 * </p>

	 * 

	 * @return a {@link java.util.List} object.

	 */

	protected abstract List<T> preferredTerms();

	/**

	 * May be overridden by derived classes if the desired label string does not

	 * reside in term.getLabel();

	 * 

	 * @param term

	 *            a T object.

	 * @return a {@link java.lang.String} object.

	 */

	protected String getLabel(T term) {

		return term.getLabel(CdmStore.getDefaultLanguage());

	}

	private void createTermNotInPreferredTerms(T term) {

		List<T> preferredTerms = preferredTerms();

		preferredTerms.add(term);

		populateTerms(preferredTerms);

	}

	/**

	 * <p>

	 * addSelectionListener

	 * </p>

	 * 

	 * @param listener

	 *            a {@link org.eclipse.swt.events.SelectionListener} object.

	 */

	public void addSelectionListener(SelectionListener listener) {

		combo.addSelectionListener(listener);

	}

	/**

	 * <p>

	 * removeSelectionListener

	 * </p>

	 * 

	 * @param listener

	 *            a {@link org.eclipse.swt.events.SelectionListener} object.

	 */

	public void removeSelectionListener(SelectionListener listener) {

		combo.removeSelectionListener(listener);

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see

	 * org.eclipse.swt.events.SelectionListener#widgetSelected(org.eclipse.swt

	 * .events.SelectionEvent)

	 */

	/** {@inheritDoc} */

	public void widgetSelected(SelectionEvent e) {

		selection = terms.get(combo.getSelectionIndex());

		firePropertyChangeEvent(new CdmPropertyChangeEvent(this, e));

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see java.beans.PropertyChangeListener#propertyChange(java.beans.

	 * PropertyChangeEvent)

	 */

	/** {@inheritDoc} */

	public void propertyChange(PropertyChangeEvent event) {

		super.propertyChange(event);

		if (event != null

				&& PreferencesUtil.PREFERRED_TERMS_CHANGE.equals(event

						.getProperty())) {

			populateTerms(preferredTerms());

		}

	}

	/** {@inheritDoc} */

	public void setSelected(boolean selected) {

		setBackground(selected ? SELECTED : getPersistentBackground());

	}

	/** {@inheritDoc} */

	public void widgetDisposed(DisposeEvent e) {

		PreferencesUtil.getPreferenceStore().removePropertyChangeListener(this);

	}

	// not used

	/** {@inheritDoc} */

	public void widgetDefaultSelected(SelectionEvent e) {

	}

	/** {@inheritDoc} */

	public void setIrrelevant(boolean irrelevant) {

		String colorId = irrelevant ? Resources.COLOR_COMPOSITE_IRRELEVANT

				: Resources.COLOR_COMPOSITE_BACKGROUND;

		Color color = StoreUtil.getColor(colorId);

		combo.setBackground(color);

	}

	/** {@inheritDoc} */

	@Override

	public void setBackground(Color color) {

		if (label != null)

			label.setBackground(color);

	}

	/**

	 * 

	 */

	protected TermManager getTermManager() {

		return CdmStore.getTermManager();

	}

}