/*******************************************************************************
 * 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.circuit;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;

import com.cburch.logisim.comp.Component;
import com.cburch.logisim.data.Attribute;
import com.cburch.logisim.data.AttributeSet;

class CircuitMutatorImpl implements CircuitMutator {
	private ArrayList<CircuitChange> log;
	private HashMap<Circuit, ReplacementMap> replacements;
	private HashSet<Circuit> modified;

	public CircuitMutatorImpl() {
		log = new ArrayList<CircuitChange>();
		replacements = new HashMap<Circuit, ReplacementMap>();
		modified = new HashSet<Circuit>();
	}

	public void add(Circuit circuit, Component comp) {
		modified.add(circuit);
		log.add(CircuitChange.add(circuit, comp));

		ReplacementMap repl = new ReplacementMap();
		repl.add(comp);
		getMap(circuit).append(repl);

		circuit.mutatorAdd(comp);
	}

	public void clear(Circuit circuit) {
		HashSet<Component> comps = new HashSet<Component>(circuit.getNonWires());
		comps.addAll(circuit.getWires());
		if (!comps.isEmpty())
			modified.add(circuit);
		log.add(CircuitChange.clear(circuit, comps));

		ReplacementMap repl = new ReplacementMap();
		for (Component comp : comps)
			repl.remove(comp);
		getMap(circuit).append(repl);

		circuit.mutatorClear();
	}

	private ReplacementMap getMap(Circuit circuit) {
		ReplacementMap ret = replacements.get(circuit);
		if (ret == null) {
			ret = new ReplacementMap();
			replacements.put(circuit, ret);
		}
		return ret;
	}

	Collection<Circuit> getModifiedCircuits() {
		return Collections.unmodifiableSet(modified);
	}

	ReplacementMap getReplacementMap(Circuit circuit) {
		return replacements.get(circuit);
	}

	CircuitTransaction getReverseTransaction() {
		CircuitMutation ret = new CircuitMutation();
		ArrayList<CircuitChange> log = this.log;
		for (int i = log.size() - 1; i >= 0; i--) {
			ret.change(log.get(i).getReverseChange());
		}
		return ret;
	}

	void markModified(Circuit circuit) {
		modified.add(circuit);
	}

	public void remove(Circuit circuit, Component comp) {
		if (circuit.contains(comp)) {
			modified.add(circuit);
			log.add(CircuitChange.remove(circuit, comp));

			ReplacementMap repl = new ReplacementMap();
			repl.remove(comp);
			getMap(circuit).append(repl);

			circuit.mutatorRemove(comp);
		}
	}

	public void replace(Circuit circuit, Component prev, Component next) {
		replace(circuit, new ReplacementMap(prev, next));
	}

	public void replace(Circuit circuit, ReplacementMap repl) {
		if (!repl.isEmpty()) {
			modified.add(circuit);
			log.add(CircuitChange.replace(circuit, repl));

			repl.freeze();
			getMap(circuit).append(repl);

			for (Component c : repl.getRemovals()) {
				circuit.mutatorRemove(c);
			}
			for (Component c : repl.getAdditions()) {
				circuit.mutatorAdd(c);
			}
		}
	}

	public void set(Circuit circuit, Component comp, Attribute<?> attr,
			Object newValue) {
		if (circuit.contains(comp)) {
			modified.add(circuit);
			@SuppressWarnings("unchecked")
			Attribute<Object> a = (Attribute<Object>) attr;
			AttributeSet attrs = comp.getAttributeSet();
			Object oldValue = attrs.getValue(a);
			log.add(CircuitChange.set(circuit, comp, attr, oldValue, newValue));
			attrs.setValue(a, newValue);
		}
	}

	public void setForCircuit(Circuit circuit, Attribute<?> attr,
			Object newValue) {
		@SuppressWarnings("unchecked")
		Attribute<Object> a = (Attribute<Object>) attr;
		AttributeSet attrs = circuit.getStaticAttributes();
		Object oldValue = attrs.getValue(a);
		log.add(CircuitChange.setForCircuit(circuit, attr, oldValue, newValue));
		attrs.setValue(a, newValue);
		if (attr == CircuitAttributes.NAME_ATTR ||
			attr == CircuitAttributes.NAMED_CIRCUIT_BOX) {
			circuit.getAppearance().recomputeDefaultAppearance();
		}
	}
}