DefaultMapper.java

/*
 * MX Cheminformatics Tools for Java
 * 
 * Copyright (c) 2007, 2008 Metamolecular, LLC
 * 
 * http://metamolecular.com
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

package com.chemhack.jsMolEditor.client.map;

import com.chemhack.jsMolEditor.client.model.Atom;
import com.chemhack.jsMolEditor.client.model.Molecule;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * @author Richard L. Apodaca
 *         Duan Lian
 */
public class DefaultMapper implements Mapper {
    private Molecule query;
    private List<Map<Atom, Atom>> maps;

    public DefaultMapper(Molecule query) {
        this.query = query;
        this.maps = new ArrayList<Map<Atom, Atom>>();
    }

    public List<Map<Atom, Atom>> getMaps(Molecule target) {
        DefaultState state = new DefaultState(query, target);

        maps.clear();

        mapAll(state);

        return new ArrayList<Map<Atom, Atom>>(maps);
    }

    public int countMaps(Molecule target) {
        DefaultState state = new DefaultState(query, target);

        maps.clear();

        mapAll(state);

        return maps.size();
    }

    public Map<Atom, Atom> getFirstMap(Molecule target) {
        DefaultState state = new DefaultState(query, target);

        maps.clear();

        mapFirst(state);

        return maps.isEmpty() ? new HashMap<Atom, Atom>() : maps.get(0);
    }

    public boolean hasMap(Molecule target) {
        DefaultState state = new DefaultState(query, target);

        maps.clear();

        return mapFirst(state);
    }

    private void mapAll(State state) {
        if (state.isDead()) {
            return;
        }

        if (state.isGoal()) {
            Map<Atom, Atom> map = state.getMap();

            if (!hasMap(map)) {
                maps.add(state.getMap());
            }

            return;
        }

        while (state.hasNextCandidate()) {
            Match candidate = state.nextCandidate();

            if (state.isMatchFeasible(candidate)) {
                State nextState = state.nextState(candidate);

                mapAll(nextState);

                nextState.backTrack();
            }
        }
    }

    private boolean mapFirst(State state) {
        if (state.isDead()) {
            return false;
        }

        if (state.isGoal()) {
            maps.add(state.getMap());

            return true;
        }

        boolean found = false;

        while (!found && state.hasNextCandidate()) {
            Match candidate = state.nextCandidate();

            if (state.isMatchFeasible(candidate)) {
                State nextState = state.nextState(candidate);
                found = mapFirst(nextState);

                nextState.backTrack();
            }
        }

        return found;
    }

    private boolean hasMap(Map<Atom, Atom> map) {
        for (Map<Atom, Atom> test : maps) {
            if (test.equals(map)) {
                return true;
            }
        }

        return false;
    }
}