InstanceExplorer.java

/*
 * Copyright (c) 2012 Data Harmonisation Panel
 * 
 * All rights reserved. This program and the accompanying materials are made
 * available under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the License,
 * or (at your option) any later version.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution. If not, see <http://www.gnu.org/licenses/>.
 * 
 * Contributors:
 *     HUMBOLDT EU Integrated Project #030962
 *     Data Harmonisation Panel <http://www.dhpanel.eu>
 */

package eu.esdihumboldt.hale.ui.views.data.internal.explore;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import org.eclipse.jface.layout.GridDataFactory;
import org.eclipse.jface.layout.GridLayoutFactory;
import org.eclipse.jface.layout.TreeColumnLayout;
import org.eclipse.jface.viewers.ColumnViewerToolTipSupport;
import org.eclipse.jface.viewers.ColumnWeightData;
import org.eclipse.jface.viewers.ISelectionProvider;
import org.eclipse.jface.viewers.TreeColumnViewerLabelProvider;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.jface.viewers.TreeViewerColumn;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerCell;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.TreeEditor;
import org.eclipse.swt.dnd.Clipboard;
import org.eclipse.swt.dnd.TextTransfer;
import org.eclipse.swt.dnd.Transfer;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.events.MouseMoveListener;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.TreeItem;
import org.eclipse.ui.ISharedImages;
import org.eclipse.ui.PlatformUI;

import com.google.common.collect.Iterables;

import eu.esdihumboldt.hale.common.instance.model.Instance;
import eu.esdihumboldt.hale.common.schema.SchemaSpaceID;
import eu.esdihumboldt.hale.common.schema.model.TypeDefinition;
import eu.esdihumboldt.hale.ui.util.viewer.PairLabelProvider;
import eu.esdihumboldt.hale.ui.views.data.InstanceViewer;
import eu.esdihumboldt.hale.ui.views.data.internal.MetadataActionProvider;
import eu.esdihumboldt.hale.ui.views.data.internal.SimpleInstanceSelectionProvider;
import eu.esdihumboldt.util.Pair;

/**
 * Instance explorer
 * 
 * @author Simon Templer
 */
public class InstanceExplorer implements InstanceViewer {

	private final SimpleInstanceSelectionProvider selectionProvider = new SimpleInstanceSelectionProvider();

	private Composite selectorComposite;

	private Composite main;

	private TreeViewer viewer;

	private TreeEditor editor;

	private List<Instance> instances = new ArrayList<Instance>();

	private final List<Control> selectButtons = new ArrayList<Control>();

	private int selectedIndex = 0;

	// private static ALogger _log =
	// ALoggerFactory.getLogger(InstanceExplorer.class);

	private final SelectionListener selectListener = new SelectionAdapter() {

		@Override
		public void widgetSelected(SelectionEvent e) {
			int index = 0;
			for (Control button : selectButtons) {
				if (button instanceof Button && ((Button) button).getSelection()) {
					selectedIndex = index;
					updateSelection();
					return;
				}

				index++;
			}
		}

	};

	/**
	 * @see InstanceViewer#createControls(Composite, SchemaSpaceID)
	 */
	@Override
	public void createControls(Composite parent, SchemaSpaceID schemaSpace) {
		main = new Composite(parent, SWT.NONE);
		main.setLayout(GridLayoutFactory.fillDefaults().numColumns(1).create());

		// selector composite
		selectorComposite = new Composite(main, SWT.NONE);
		selectorComposite.setLayoutData(GridDataFactory.swtDefaults().create());
		selectorComposite.setLayout(GridLayoutFactory.fillDefaults().create());

		// viewer composite
		Composite viewerComposite = new Composite(main, SWT.NONE);
		viewerComposite.setLayoutData(GridDataFactory.fillDefaults().grab(true, true).create());
		TreeColumnLayout layout = new TreeColumnLayout();
		viewerComposite.setLayout(layout);
		viewer = new TreeViewer(viewerComposite, SWT.SINGLE | SWT.FULL_SELECTION | SWT.BORDER);
		viewer.getTree().setLinesVisible(true);

		// set content provider
		viewer.setContentProvider(new InstanceContentProvider());
		viewer.setAutoExpandLevel(TreeViewer.ALL_LEVELS);
		// TODO set label provider?

		// add definition columns
		TreeViewerColumn column = new TreeViewerColumn(viewer, SWT.LEFT);
		column.getColumn().setText("Definition");
		column.setLabelProvider(new TreeColumnViewerLabelProvider(new PairLabelProvider(true,
				new DefinitionMetaLabelProvider(viewer, false, true))));
		layout.setColumnData(column.getColumn(), new ColumnWeightData(1));

		// add value column
		column = new TreeViewerColumn(viewer, SWT.LEFT);
		column.getColumn().setText("Value");
		final InstanceValueLabelProvider instanceLabelProvider = new InstanceValueLabelProvider();
		column.setLabelProvider(instanceLabelProvider);
		// new PairLabelProvider(false, new LabelProvider())));

		ColumnViewerToolTipSupport.enableFor(viewer);

		layout.setColumnData(column.getColumn(), new ColumnWeightData(1));

		MetadataActionProvider maep = new MetadataExploreActionProvider(viewer);
		maep.setup();

		// Add an editor for copying instance values
		editor = new TreeEditor(viewer.getTree());
		editor.horizontalAlignment = SWT.RIGHT;
		viewer.getTree().addMouseMoveListener(new MouseMoveListener() {

			@Override
			public void mouseMove(MouseEvent e) {
				final ViewerCell cell = viewer.getCell(new Point(e.x, e.y));

				// Selected cell changed?
				if (cell == null || editor.getItem() != cell.getItem()
						|| editor.getColumn() != cell.getColumnIndex()) {
					// Clean up any previous editor control
					Control oldEditor = editor.getEditor();
					if (oldEditor != null) {
						oldEditor.dispose();
						editor.setEditor(null, null, 0);
					}
				}

				// No valid selected cell
				if (cell == null || cell.getColumnIndex() == 0) {
					return;
				}

				// cell didn't change
				if ((editor.getItem() == cell.getItem() && editor.getColumn() == cell
						.getColumnIndex())) {
					return;
				}

				// determine instance value
				Object value = ((Pair<?, ?>) cell.getViewerRow().getTreePath().getLastSegment())
						.getSecond();
				if (value instanceof Instance) {
					value = ((Instance) value).getValue();
				}

				// copy button
				if (value != null) {
					final String textValue = value.toString();

					if (!textValue.isEmpty()) { // empty string invalid for
												// clipboard
						Button button = new Button(viewer.getTree(), SWT.PUSH | SWT.FLAT);
						button.setImage(PlatformUI.getWorkbench().getSharedImages()
								.getImage(ISharedImages.IMG_TOOL_COPY));
						button.setToolTipText("Copy string value");
						button.addSelectionListener(new SelectionAdapter() {

							@Override
							public void widgetSelected(SelectionEvent e) {
								// copy content to clipboard
								Clipboard clipBoard = new Clipboard(Display.getCurrent());
								clipBoard.setContents(new Object[] { textValue },
										new Transfer[] { TextTransfer.getInstance() });
								clipBoard.dispose();
							}
						});

						// calculate editor size
						Point size = button.computeSize(SWT.DEFAULT, SWT.DEFAULT);
						editor.minimumHeight = size.y;
						editor.minimumWidth = size.x;

						editor.setEditor(button, (TreeItem) cell.getItem(), cell.getColumnIndex());
					}
				}
			}
		});

		update();
	}

	/**
	 * Update the controls.
	 */
	private void update() {
		// dispose old selector buttons
		for (Control button : selectButtons) {
			button.dispose();
		}
		selectButtons.clear();

		selectorComposite.setLayout(GridLayoutFactory.swtDefaults()
				.numColumns((instances.isEmpty()) ? (1) : (instances.size())).margins(3, 0)
				.create());
		// create new buttons for each instance
		for (int index = 0; index < instances.size(); index++) {
			Button button = new Button(selectorComposite, SWT.RADIO);
			button.setText("#" + (index + 1));
			button.setSelection(selectedIndex == index);
			button.addSelectionListener(selectListener);

			selectButtons.add(button);
		}

		if (selectButtons.isEmpty()) {
			Label none = new Label(selectorComposite, SWT.NONE);
			none.setText("No matching instances available");
			selectButtons.add(none);
		}

		if (selectedIndex >= selectButtons.size()) {
			selectedIndex = 0;
			if (!selectButtons.isEmpty()) {
				Control c1 = selectButtons.get(0);
				if (c1 instanceof Button) {
					((Button) c1).setSelection(true);
				}
			}
		}

		// both layout steps needed
		selectorComposite.layout();
		selectorComposite.getParent().layout();

		updateSelection();
	}

	/**
	 * Update the viewer according to the current selection.
	 */
	private void updateSelection() {
		if (selectedIndex < instances.size()) {
			Instance instance = instances.get(selectedIndex);
			viewer.setInput(instance);
			selectionProvider.updateSelection(Collections.singleton(instance));
		}
		else {
			viewer.setInput(null);
			selectionProvider.updateSelection(null);
		}
	}

	/**
	 * @see InstanceViewer#setInput(TypeDefinition, Iterable)
	 */
	@Override
	public void setInput(TypeDefinition type, Iterable<Instance> instances) {
		List<Instance> instanceList = new ArrayList<Instance>();
		if (instances != null) {
			Iterables.addAll(instanceList, instances);
		}
		this.instances = instanceList;
		update();
	}

	/**
	 * @see InstanceViewer#getViewer()
	 */
	@Override
	public Viewer getViewer() {
		return viewer;
	}

	/**
	 * @see InstanceViewer#getControl()
	 */
	@Override
	public Control getControl() {
		return main;
	}

	/**
	 * @see InstanceViewer#getInstanceSelectionProvider()
	 */
	@Override
	public ISelectionProvider getInstanceSelectionProvider() {
		return selectionProvider;
	}

}