Dependencies.java

/*******************************************************************************
 * This file is part of logisim-evolution.
 *
 *   logisim-evolution 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.
 *
 *   logisim-evolution 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 logisim-evolution.  If not, see <http://www.gnu.org/licenses/>.
 *
 *   Original code by Carl Burch (http://www.cburch.com), 2011.
 *   Subsequent modifications by :
 *     + Haute École Spécialisée Bernoise
 *       http://www.bfh.ch
 *     + Haute École du paysage, d'ingénierie et d'architecture de Genève
 *       http://hepia.hesge.ch/
 *     + Haute École d'Ingénierie et de Gestion du Canton de Vaud
 *       http://www.heig-vd.ch/
 *   The project is currently maintained by :
 *     + REDS Institute - HEIG-VD
 *       Yverdon-les-Bains, Switzerland
 *       http://reds.heig-vd.ch
 *******************************************************************************/

package com.cburch.logisim.proj;

import com.cburch.logisim.circuit.Circuit;
import com.cburch.logisim.circuit.CircuitEvent;
import com.cburch.logisim.circuit.CircuitListener;
import com.cburch.logisim.circuit.SubcircuitFactory;
import com.cburch.logisim.comp.Component;
import com.cburch.logisim.comp.ComponentFactory;
import com.cburch.logisim.file.LibraryEvent;
import com.cburch.logisim.file.LibraryListener;
import com.cburch.logisim.file.LogisimFile;
import com.cburch.logisim.tools.AddTool;
import com.cburch.logisim.util.Dag;

public class Dependencies {
	private class MyListener implements LibraryListener, CircuitListener {
		public void circuitChanged(CircuitEvent e) {
			Component comp;
			switch (e.getAction()) {
			case CircuitEvent.ACTION_ADD:
				comp = (Component) e.getData();
				if (comp.getFactory() instanceof SubcircuitFactory) {
					SubcircuitFactory factory = (SubcircuitFactory) comp
							.getFactory();
					depends.addEdge(e.getCircuit(), factory.getSubcircuit());
				}
				break;
			case CircuitEvent.ACTION_REMOVE:
				comp = (Component) e.getData();
				if (comp.getFactory() instanceof SubcircuitFactory) {
					SubcircuitFactory factory = (SubcircuitFactory) comp
							.getFactory();
					boolean found = false;
					for (Component o : e.getCircuit().getNonWires()) {
						if (o.getFactory() == factory) {
							found = true;
							break;
						}
					}
					if (!found)
						depends.removeEdge(e.getCircuit(),
								factory.getSubcircuit());
				}
				break;
			case CircuitEvent.ACTION_CLEAR:
				depends.removeNode(e.getCircuit());
				break;
			}
		}

		public void libraryChanged(LibraryEvent e) {
			switch (e.getAction()) {
			case LibraryEvent.ADD_TOOL:
				if (e.getData() instanceof AddTool) {
					ComponentFactory factory = ((AddTool) e.getData())
							.getFactory();
					if (factory instanceof SubcircuitFactory) {
						SubcircuitFactory circFact = (SubcircuitFactory) factory;
						processCircuit(circFact.getSubcircuit());
					}
				}
				break;
			case LibraryEvent.REMOVE_TOOL:
				if (e.getData() instanceof AddTool) {
					ComponentFactory factory = ((AddTool) e.getData())
							.getFactory();
					if (factory instanceof SubcircuitFactory) {
						SubcircuitFactory circFact = (SubcircuitFactory) factory;
						Circuit circ = circFact.getSubcircuit();
						depends.removeNode(circ);
						circ.removeCircuitListener(this);
					}
				}
				break;
			}
		}
	}

	private MyListener myListener = new MyListener();
	private Dag depends = new Dag();

	Dependencies(LogisimFile file) {
		addDependencies(file);
	}

	private void addDependencies(LogisimFile file) {
		file.addLibraryListener(myListener);
		for (Circuit circuit : file.getCircuits()) {
			processCircuit(circuit);
		}
	}

	public boolean canAdd(Circuit circ, Circuit sub) {
		return depends.canFollow(sub, circ);
	}

	public boolean canRemove(Circuit circ) {
		return !depends.hasPredecessors(circ);
	}

	private void processCircuit(Circuit circ) {
		circ.addCircuitListener(myListener);
		for (Component comp : circ.getNonWires()) {
			if (comp.getFactory() instanceof SubcircuitFactory) {
				SubcircuitFactory factory = (SubcircuitFactory) comp
						.getFactory();
				depends.addEdge(circ, factory.getSubcircuit());
			}
		}
	}

}