org.eclipse.rmf.reqif10.search.ui/src/org/eclipse/rmf/reqif10/search/filter/ui/FilterControlEnum.java

/*******************************************************************************
 * Copyright (c) 2014 Formal Mind GmbH.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     Michael Jastram - initial API and implementation
 ******************************************************************************/
package org.eclipse.rmf.reqif10.search.filter.ui;

import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;

import org.eclipse.rmf.reqif10.AttributeDefinitionEnumeration;
import org.eclipse.rmf.reqif10.EnumValue;
import org.eclipse.rmf.reqif10.pror.editor.presentation.EnumSelector;
import org.eclipse.rmf.reqif10.search.filter.EnumFilter;
import org.eclipse.rmf.reqif10.search.filter.IFilter;
import org.eclipse.rmf.reqif10.search.filter.IFilter.Operator;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Combo;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Shell;

/**
 * Used for plain text and XHTML
 * 
 * @author jastram
 */
public class FilterControlEnum extends FilterControl {
	
	private Button valueControl;
	private Combo attr;
	private AttributeDefinitionEnumeration attribute;
	private EnumFilter templateFilter;
	private Collection<EnumValue> items;

	public FilterControlEnum(FilterPanel parent,
			AttributeDefinitionEnumeration attribute) {
		super(parent, SWT.FLAT);
		this.attribute = attribute;
		init();
	}

	public FilterControlEnum(FilterPanel parent, EnumFilter template) {
		super(parent, SWT.FLAT);
		this.attribute = (AttributeDefinitionEnumeration) template.getAttribute();
		this.templateFilter = template;			
		init();		
	}

	private void init() {
		if (!(attribute instanceof AttributeDefinitionEnumeration)) {
			throw new IllegalArgumentException("Not allowed: " + attribute);
		}
		setLayout(new GridLayout(2, false));
		if (templateFilter != null) {
			items = templateFilter.getFilterValue1();
		} else {
			items = new HashSet<EnumValue>();
		}
		createOperators();
		createValueControl();
		updateItems(items);
	}

	private void createValueControl() {
		valueControl = new Button(this, SWT.PUSH | SWT.FLAT | SWT.WRAP);
		GridData layoutData = new GridData(SWT.FILL, SWT.CENTER, true, false);
		layoutData.widthHint = 200;
		valueControl.setLayoutData(layoutData);
		valueControl.addSelectionListener(new SelectionAdapter() {
			@Override
			public void widgetSelected(SelectionEvent e) {
				popupSelector(valueControl);
			}
		});
	}

	protected void popupSelector(Control control) {
		Shell shell = EnumSelector.createShell(control);
		EnumSelector selector = new EnumSelector(attribute.getType()
				.getSpecifiedValues(), items, shell, SWT.BORDER);
		int status = selector.showEnumSelector(shell);
		if (status == SWT.OK) {
			updateItems(selector.getItems());
		}
	}

	private void updateItems(Collection<EnumValue> items) {
		this.items = items;
		StringBuilder sb = new StringBuilder();
		for (Iterator<EnumValue> i = items.iterator(); i.hasNext();) {
			EnumValue value = i.next();

			// In case items have been removed
			if (! attribute.getType().getSpecifiedValues().contains(value)) continue;

			String label = value.getLongName() != null ? value.getLongName() : value.getIdentifier(); 
			sb.append(label);
			if (i.hasNext()) sb.append(", ");
		}
		valueControl.setText(sb.toString());
		getParent().layout();
		getParent().getParent().layout();
	}

	// TODO use correct operators.
	private void createOperators() {
		attr = new Combo(this, SWT.DROP_DOWN | SWT.BORDER | SWT.READ_ONLY);
		GridData layoutData = new GridData(SWT.LEFT, SWT.CENTER, false, false);
		attr.setLayoutData(layoutData);
		for (Operator operator : EnumFilter.SUPPORTED_OPERATORS) {
			attr.add(getString(operator.toString()));			
		}
		attr.select(0);
		if (templateFilter != null)
			attr.select(EnumFilter.SUPPORTED_OPERATORS.asList().indexOf(
					templateFilter.getOperator()));
	}
	
	public IFilter getFilter() {
		Operator operator = EnumFilter.SUPPORTED_OPERATORS.asList().get(attr.getSelectionIndex());
		return new EnumFilter(operator, items, attribute);
	}
}