    001package org.cpsolver.coursett.criteria;
    002
    003import java.util.Collection;
    004import java.util.HashSet;
    005import java.util.List;
    006import java.util.Set;
    007
    008import org.cpsolver.coursett.Constants;
    009import org.cpsolver.coursett.constraint.RoomConstraint;
    010import org.cpsolver.coursett.constraint.RoomConstraint.RoomConstraintContext;
    011import org.cpsolver.coursett.model.Lecture;
    012import org.cpsolver.coursett.model.Placement;
    013import org.cpsolver.coursett.model.RoomLocation;
    014import org.cpsolver.coursett.model.TimeLocation;
    015import org.cpsolver.coursett.model.TimetableModel;
    016import org.cpsolver.ifs.assignment.Assignment;
    017import org.cpsolver.ifs.util.DataProperties;
    018
    019
    020/**
    021 * Broken time patterns. This criterion counts cases when an unused space is in a room
    022 * which follows one of the standard MWF or TTh pattern. E.g., there is a penalty of
    023 * Monday is available during a time when Wednesday and/or Friday is occupied. The aim
    024 * is to use this space if possible in order to leave the available space in a way that
    025 * can be used by MWF or TTh classes.
    026 * <br>
    027 *
    028 * @version CourseTT 1.3 (University Course Timetabling)<br>
    029 *          Copyright (C) 2006 - 2014 Tomáš Müller<br>
    030 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    031 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    032 * <br>
    033 *          This library is free software; you can redistribute it and/or modify
    034 *          it under the terms of the GNU Lesser General Public License as
    035 *          published by the Free Software Foundation; either version 3 of the
    036 *          License, or (at your option) any later version. <br>
    037 * <br>
    038 *          This library is distributed in the hope that it will be useful, but
    039 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    040 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    041 *          Lesser General Public License for more details. <br>
    042 * <br>
    043 *          You should have received a copy of the GNU Lesser General Public
    044 *          License along with this library; if not see
    045 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    046 */
    047public class BrokenTimePatterns extends TimetablingCriterion {
    048    private int iFirstDaySlot, iLastDaySlot, iFirstWorkDay, iLastWorkDay;
    049
    050    public BrokenTimePatterns() {
    051        setValueUpdateType(ValueUpdateType.NoUpdate);
    052    }
    053
    054    @Override
    055    public void configure(DataProperties properties) {
    056        super.configure(properties);
    057        iFirstDaySlot = properties.getPropertyInt("General.FirstDaySlot", Constants.DAY_SLOTS_FIRST);
    058        iLastDaySlot = properties.getPropertyInt("General.LastDaySlot", Constants.DAY_SLOTS_LAST);
    059        iFirstWorkDay = properties.getPropertyInt("General.FirstWorkDay", 0);
    060        iLastWorkDay = properties.getPropertyInt("General.LastWorkDay", Constants.NR_DAYS_WEEK - 1);
    061        if (iLastWorkDay < iFirstWorkDay) iLastWorkDay += 7;
    062    }
    063
    064    @Override
    065    public double getWeightDefault(DataProperties config) {
    066        return Constants.sPreferenceLevelDiscouraged * config.getPropertyDouble("Comparator.UselessSlotWeight", 0.1);
    067    }
    068
    069    @Override
    070    public String getPlacementSelectionWeightName() {
    071        return "Placement.UselessSlotsWeight";
    072    }
    073
    074    protected double penalty(Assignment<Lecture, Placement> assignment, Placement value) {
    075        if (value.isMultiRoom()) {
    076            int ret = 0;
    077            for (RoomLocation r : value.getRoomLocations()) {
    078                if (r.getRoomConstraint() == null)
    079                    continue;
    080                ret += penalty(r.getRoomConstraint().getContext(assignment), value);
    081            }
    082            return ret;
    083        } else {
    084            return (value.getRoomLocation().getRoomConstraint() == null ? 0 : penalty(value.getRoomLocation().getRoomConstraint().getContext(assignment), value));
    085        }
    086    }
    087
    088    protected double penalty(RoomConstraintContext rc) {
    089        return countUselessSlotsBrokenTimePatterns(rc) / 6.0;
    090    }
    091
    092    protected double penalty(RoomConstraintContext rc, Placement value) {
    093        return countUselessSlotsBrokenTimePatterns(rc, value) / 6.0;
    094    }
    095
    096   @Override
    097    public double getValue(Assignment<Lecture, Placement> assignment, Placement value, Set<Placement> conflicts) {
    098        double ret = penalty(assignment, value);
    099        if (conflicts != null)
    100            for (Placement conflict: conflicts)
    101                ret -= penalty(assignment, conflict);
    102        return ret;
    103    }
    104
    105    @Override
    106    public double getValue(Assignment<Lecture, Placement> assignment, Collection<Lecture> variables) {
    107        double ret = 0;
    108        Set<RoomConstraint> constraints = new HashSet<RoomConstraint>();
    109        for (Lecture lect: variables) {
    110            Placement placement = assignment.getValue(lect);
    111            if (placement == null) continue;
    112            if (placement.isMultiRoom()) {
    113                for (RoomLocation r : placement.getRoomLocations()) {
    114                    if (r.getRoomConstraint() != null && constraints.add(r.getRoomConstraint()))
    115                        ret += penalty(r.getRoomConstraint().getContext(assignment));
    116                }
    117            } else if (placement.getRoomLocation().getRoomConstraint() != null &&
    118                    constraints.add(placement.getRoomLocation().getRoomConstraint())) {
    119                ret += penalty(placement.getRoomLocation().getRoomConstraint().getContext(assignment));
    120            }
    121        }
    122        return ret;
    123    }
    124
    125    @Override
    126    protected double[] computeBounds(Assignment<Lecture, Placement> assignment) {
    127        return new double[] {
    128                ((TimetableModel)getModel()).getRoomConstraints().size() * (iLastWorkDay - iFirstWorkDay + 1) * (iLastDaySlot - iFirstDaySlot + 1),
    129                0.0 };
    130    }
    131
    132    @Override
    133    public double[] getBounds(Assignment<Lecture, Placement> assignment, Collection<Lecture> variables) {
    134        Set<RoomConstraint> constraints = new HashSet<RoomConstraint>();
    135        for (Lecture lect: variables) {
    136            Placement placement = assignment.getValue(lect);
    137            if (placement == null) continue;
    138            if (placement.isMultiRoom()) {
    139                for (RoomLocation r : placement.getRoomLocations()) {
    140                    if (r.getRoomConstraint() != null)
    141                        constraints.add(r.getRoomConstraint());
    142                }
    143            } else if (placement.getRoomLocation().getRoomConstraint() != null) {
    144                constraints.add(placement.getRoomLocation().getRoomConstraint());
    145            }
    146        }
    147        return new double[] {
    148                constraints.size() * (iLastWorkDay - iFirstWorkDay + 1) * (iLastDaySlot - iFirstDaySlot + 1),
    149                0.0 };
    150    }
    151
    152    private static int sDaysMWF = Constants.DAY_CODES[0] + Constants.DAY_CODES[2] + Constants.DAY_CODES[4];
    153    private static int sDaysTTh = Constants.DAY_CODES[1] + Constants.DAY_CODES[3];
    154
    155    private static boolean isEmpty(RoomConstraintContext rc, int s, int d, Placement placement) {
    156        List<Placement> assigned = rc.getPlacements(d * Constants.SLOTS_PER_DAY + s);
    157        return assigned.isEmpty() || (placement != null && assigned.size() == 1 && assigned.get(0).variable().equals(placement.variable()));
    158    }
    159
    160    /** Number of broken time patterns for this room
    161     * @param rc room constraint
    162     * @param placement placement that is being considered
    163     * @return number of broken time patterns caused by the given placement
    164     **/
    165    protected static int countUselessSlotsBrokenTimePatterns(RoomConstraintContext rc, Placement placement) {
    166        int ret = 0;
    167        TimeLocation time = placement.getTimeLocation();
    168        int slot = time.getStartSlot() % Constants.SLOTS_PER_DAY;
    169        int days = time.getDayCode();
    170        if ((days & sDaysMWF) != 0 && (days & sDaysMWF) != sDaysMWF) {
    171            for (int s = slot; s < slot + time.getLength(); s++) {
    172                int d = (days & sDaysMWF);
    173                if (d == Constants.DAY_CODES[0] && isEmpty(rc, s, 0, placement)) {
    174                    if (isEmpty(rc, s, 2, placement) != isEmpty(rc, s, 4, placement)) ret ++;
    175                    if (!isEmpty(rc, s, 2, placement) && !isEmpty(rc, s, 4, placement)) ret --;
    176                } else if (d == Constants.DAY_CODES[2] && isEmpty(rc, s, 2, placement)) {
    177                    if (isEmpty(rc, s, 0, placement) != isEmpty(rc, s, 4, placement)) ret ++;
    178                    if (!isEmpty(rc, s, 0, placement) && !isEmpty(rc, s, 4, placement)) ret --;
    179                } else if (d == Constants.DAY_CODES[4] && isEmpty(rc, s, 4, placement)) {
    180                    if (isEmpty(rc, s, 0, placement) != isEmpty(rc, s, 2, placement)) ret ++;
    181                    if (!isEmpty(rc, s, 0, placement) && !isEmpty(rc, s, 2, placement)) ret --;
    182                } else if (d == (Constants.DAY_CODES[0] | Constants.DAY_CODES[2]) && isEmpty(rc, s, 0, placement) && isEmpty(rc, s, 2, placement)) {
    183                    if (isEmpty(rc, s, 4, placement)) ret ++;
    184                } else if (d == (Constants.DAY_CODES[2] | Constants.DAY_CODES[4]) && isEmpty(rc, s, 2, placement) && isEmpty(rc, s, 4, placement)) {
    185                    if (isEmpty(rc, s, 0, placement)) ret ++;
    186                } else if (d == (Constants.DAY_CODES[0] | Constants.DAY_CODES[4]) && isEmpty(rc, s, 0, placement) && isEmpty(rc, s, 4, placement)) {
    187                    if (isEmpty(rc, s, 2, placement)) ret ++;
    188                }
    189            }
    190        }
    191        if ((days & sDaysTTh) != 0 && (days & sDaysTTh) != sDaysTTh) {
    192            for (int s = slot; s < slot + time.getLength(); s++) {
    193                if (isEmpty(rc, s, 1, placement) && isEmpty(rc, s, 3, placement)) ret ++;
    194                int d = (days & sDaysTTh);
    195                if (d == Constants.DAY_CODES[1] && isEmpty(rc, s, 1, placement) && !isEmpty(rc, s, 3, placement)) ret --;
    196                if (d == Constants.DAY_CODES[3] && isEmpty(rc, s, 3, placement) && !isEmpty(rc, s, 1, placement)) ret --;
    197            }
    198        }
    199        return ret;
    200    }
    201
    202    /** Number of useless slots for this room
    203     * @param rc room constraint
    204     * @return current penalty for the given room
    205     **/
    206    public static int countUselessSlotsBrokenTimePatterns(RoomConstraintContext rc) {
    207        int ret = 0;
    208        for (int d = 0; d < Constants.NR_DAYS; d++) {
    209            for (int s = 0; s < Constants.SLOTS_PER_DAY; s++) {
    210                int slot = d * Constants.SLOTS_PER_DAY + s;
    211                if (rc.getPlacements(slot).isEmpty()) {
    212                    switch (d) {
    213                        case 0:
    214                            if (!rc.getPlacements(2 * Constants.SLOTS_PER_DAY + s).isEmpty() && !rc.getPlacements(4 * Constants.SLOTS_PER_DAY + s).isEmpty())
    215                                ret++;
    216                            break;
    217                        case 1:
    218                            if (!rc.getPlacements(3 * Constants.SLOTS_PER_DAY + s).isEmpty())
    219                                ret++;
    220                            break;
    221                        case 2:
    222                            if (!rc.getPlacements(0 * Constants.SLOTS_PER_DAY + s).isEmpty() && !rc.getPlacements(4 * Constants.SLOTS_PER_DAY + s).isEmpty())
    223                                ret++;
    224                            break;
    225                        case 3:
    226                            if (!rc.getPlacements(1 * Constants.SLOTS_PER_DAY + s).isEmpty())
    227                                ret++;
    228                            break;
    229                        case 4:
    230                            if (!rc.getPlacements(0 * Constants.SLOTS_PER_DAY + s).isEmpty() && !rc.getPlacements(2 * Constants.SLOTS_PER_DAY + s).isEmpty())
    231                                ret++;
    232                            break;
    233                    }
    234                }
    235            }
    236        }
    237        return ret;
    238    }
    239}