PasteCommand.java

/*
 * Copyright (C) 2012 Jason Gedge <http://www.gedge.ca>
 *
 * This file is part of the OpGraph project.
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package ca.gedge.opgraph.app.commands.edit;

import java.awt.GraphicsEnvironment;
import java.awt.Toolkit;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import java.util.logging.Logger;

import javax.swing.AbstractAction;
import javax.swing.KeyStroke;
import javax.swing.undo.CompoundEdit;

import ca.gedge.opgraph.InputField;
import ca.gedge.opgraph.OpLink;
import ca.gedge.opgraph.OpGraph;
import ca.gedge.opgraph.OpNode;
import ca.gedge.opgraph.OutputField;
import ca.gedge.opgraph.app.GraphDocument;
import ca.gedge.opgraph.app.GraphEditorModel;
import ca.gedge.opgraph.app.edits.graph.AddLinkEdit;
import ca.gedge.opgraph.app.edits.graph.AddNodeEdit;
import ca.gedge.opgraph.app.extensions.NodeMetadata;
import ca.gedge.opgraph.app.util.GraphUtils;
import ca.gedge.opgraph.dag.CycleDetectedException;
import ca.gedge.opgraph.dag.VertexNotFoundException;
import ca.gedge.opgraph.exceptions.ItemMissingException;

/**
 * Paste copied nodes (if any) from the system clipboard into the current graph.
 */
public class PasteCommand extends AbstractAction {
	/** Logger */
	private static final Logger LOGGER = Logger.getLogger(PasteCommand.class.getName());

	/**
	 * Default constructor.
	 */
	public PasteCommand() {
		super("Paste");
		putValue(ACCELERATOR_KEY, KeyStroke.getKeyStroke(KeyEvent.VK_V, Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()));
	}

	//
	// AbstractAction
	//

	@Override
	public void actionPerformed(ActionEvent e) {
		if(GraphicsEnvironment.isHeadless())
			return;

		final GraphDocument document = GraphEditorModel.getActiveDocument();
		if(document != null) {
			// Check to make sure the clipboard has something we can paste
			final Transferable clipboardContents = Toolkit.getDefaultToolkit().getSystemClipboard().getContents(this);
			if(clipboardContents != null && clipboardContents.isDataFlavorSupported(SubgraphClipboardContents.copyFlavor)) {
				try {
					final SubgraphClipboardContents nodeClipboardContents = 
							SubgraphClipboardContents.class.cast(clipboardContents.getTransferData(SubgraphClipboardContents.copyFlavor));

					final CompoundEdit cmpEdit = new CompoundEdit();
					final OpGraph graph = document.getGraph();
					final Map<String, String> nodeMap = new HashMap<String, String>();

					// Keep track of the number of times this graph has been pasted
					Integer timesDuplicated = nodeClipboardContents.graphDuplicates.get(graph);
					if(timesDuplicated == null) {
						timesDuplicated = 0;
					} else {
						timesDuplicated = timesDuplicated + 1;
					}

					nodeClipboardContents.graphDuplicates.put(graph, timesDuplicated);

					// Create a new node edit for each node in the contents
					final Collection<OpNode> newNodes = new ArrayList<OpNode>();
					for(OpNode node : nodeClipboardContents.subGraph.getVertices()) {
						// Clone the node
						final OpNode newNode = GraphUtils.cloneNode(node);
						newNodes.add(newNode);
						nodeMap.put(node.getId(), newNode.getId());

						// Offset to avoid pasting on top of current nodes
						final NodeMetadata metadata = newNode.getExtension(NodeMetadata.class);
						if(metadata != null) {
							metadata.setX(metadata.getX() + (50 * timesDuplicated));
							metadata.setY(metadata.getY() + (30 * timesDuplicated));
						}

						// Add an undoable edit for this node
						cmpEdit.addEdit(new AddNodeEdit(graph, newNode));
					}

					// Pasted node become the selection
					document.getSelectionModel().setSelectedNodes(newNodes);

					// Add copied node to graph
					for(OpLink link : nodeClipboardContents.subGraph.getEdges()) {
						final OpNode srcNode = graph.getNodeById(nodeMap.get(link.getSource().getId()), false);
						final OutputField srcField = srcNode.getOutputFieldWithKey(link.getSourceField().getKey());
						final OpNode dstNode = graph.getNodeById(nodeMap.get(link.getDestination().getId()), false);
						final InputField dstField = dstNode.getInputFieldWithKey(link.getDestinationField().getKey());

						try {
							final OpLink newLink = new OpLink(srcNode, srcField, dstNode, dstField);
							cmpEdit.addEdit(new AddLinkEdit(graph, newLink));
						} catch(ItemMissingException exc) {
							LOGGER.severe(exc.getMessage());
						} catch(VertexNotFoundException exc) {
							LOGGER.severe(exc.getMessage());
						} catch(CycleDetectedException exc) {
							LOGGER.severe(exc.getMessage());
						}
					}

					// Add the compound edit to the undo manager
					cmpEdit.end();
					document.getUndoSupport().postEdit(cmpEdit);
				} catch(UnsupportedFlavorException exc) {
					LOGGER.severe(exc.getMessage());
				} catch(IOException exc) {
					LOGGER.severe(exc.getMessage());
				}
			}
		}
	}
}