package de.eiswind.paris.client.core.databinding;

import org.eclipse.core.databinding.observable.set.IObservableSet;
import org.eclipse.core.databinding.observable.set.ISetChangeListener;
import org.eclipse.core.databinding.observable.set.SetChangeEvent;
import org.eclipse.jface.viewers.TableViewer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.TableItem;

public class TableViewerCheckBoxBinding implements ISetChangeListener {

	private IObservableSet checked;

	private TableViewer tableViewer;

	public TableViewerCheckBoxBinding(TableViewer viewer, IObservableSet checked) {

		this.tableViewer = viewer;
		this.checked = checked;
		setCheckedItems();

		viewer.getTable().addListener(SWT.Selection, new Listener() {
			public void handleEvent(Event e) {
				if (e.detail == SWT.CHECK) {
					handleCheckEvent(e);
				}

			}
		});
		checked.addSetChangeListener(this);
	}

	@Override
	public void handleSetChange(SetChangeEvent event) {
		setCheckedItems();
	}

	private void setCheckedItems() {
		TableItem[] items = tableViewer.getTable().getItems();
		for (int i = 0; i < items.length; i++) {
			items[i].setChecked(checked.contains(items[i].getData()));
		}
	}

	private void handleCheckEvent(Event e) {
		TableItem item = (TableItem) e.item;
		Object check = item.getData();
		if (item.getChecked() == true) {
			checked.add(check);
		} else {
			checked.remove(check);
		}
	}
}