    001package org.cpsolver.coursett.criteria;
    002
    003import java.util.Collection;
    004import java.util.HashSet;
    005import java.util.Set;
    006
    007import org.cpsolver.coursett.Constants;
    008import org.cpsolver.coursett.constraint.JenrlConstraint;
    009import org.cpsolver.coursett.model.Lecture;
    010import org.cpsolver.coursett.model.Placement;
    011import org.cpsolver.coursett.model.Student;
    012import org.cpsolver.coursett.model.TimeLocation;
    013import org.cpsolver.coursett.model.TimetableModel;
    014import org.cpsolver.ifs.assignment.Assignment;
    015import org.cpsolver.ifs.util.DataProperties;
    016import org.cpsolver.ifs.util.DistanceMetric;
    017
    018
    019/**
    020 * Student conflicts. This criterion counts student conflicts between classes. A conflict
    021 * occurs when two classes that are attended by the same student (or students) are overlapping
    022 * in time or place back-to-back in rooms that are too far a part. The combinations of classes
    023 * that share students are maintained by {@link JenrlConstraint}.
    024 * <br>
    025 *
    026 * @version CourseTT 1.3 (University Course Timetabling)<br>
    027 *          Copyright (C) 2006 - 2014 Tomáš Müller<br>
    028 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    029 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    030 * <br>
    031 *          This library is free software; you can redistribute it and/or modify
    032 *          it under the terms of the GNU Lesser General Public License as
    033 *          published by the Free Software Foundation; either version 3 of the
    034 *          License, or (at your option) any later version. <br>
    035 * <br>
    036 *          This library is distributed in the hope that it will be useful, but
    037 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    038 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    039 *          Lesser General Public License for more details. <br>
    040 * <br>
    041 *          You should have received a copy of the GNU Lesser General Public
    042 *          License along with this library; if not see
    043 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    044 */
    045public class StudentConflict extends TimetablingCriterion {
    046    protected boolean iIncludeConflicts = false;
    047
    048    public StudentConflict() {
    049        setValueUpdateType(ValueUpdateType.BeforeUnassignedBeforeAssigned);
    050    }
    051
    052    @Override
    053    public void configure(DataProperties properties) {
    054        super.configure(properties);
    055        iIncludeConflicts = properties.getPropertyBoolean("StudentConflict.IncludeConflicts", false);
    056    }
    057
    058    @Override
    059    public String getPlacementSelectionWeightName() {
    060        return null;
    061    }
    062
    063    public DistanceMetric getMetrics() {
    064        return (getModel() == null ? null : ((TimetableModel)getModel()).getDistanceMetric());
    065    }
    066
    067    public static boolean overlaps(Placement p1, Placement p2) {
    068        return p1 != null && p2 != null && p1.getTimeLocation().hasIntersection(p2.getTimeLocation()) && (!p1.variable().isCommitted() || !p2.variable().isCommitted());
    069    }
    070
    071    protected double jointEnrollment(JenrlConstraint jenrl, Placement p1, Placement p2) {
    072        return jointEnrollment(jenrl);
    073    }
    074
    075    protected double jointEnrollment(JenrlConstraint jenrl) {
    076        return jenrl.jenrl();
    077    }
    078
    079    public static boolean distance(DistanceMetric m, Placement p1, Placement p2) {
    080        if (m == null && p1 != null) m = ((TimetableModel)p1.variable().getModel()).getDistanceMetric();
    081        if (m == null && p2 != null) m = ((TimetableModel)p2.variable().getModel()).getDistanceMetric();
    082        if (p1 == null || p2 == null || m == null) return false;
    083        if (p1.variable().isCommitted() && p2.variable().isCommitted()) return false;
    084        TimeLocation t1 = p1.getTimeLocation(), t2 = p2.getTimeLocation();
    085        if (!t1.shareDays(t2) || !t1.shareWeeks(t2)) return false;
    086        if (m.doComputeDistanceConflictsBetweenNonBTBClasses()) {
    087            if (t1.getStartSlot() + t1.getLength() <= t2.getStartSlot()) {
    088                return Placement.getDistanceInMinutes(m, p1, p2) > t1.getBreakTime() + Constants.SLOT_LENGTH_MIN * (t2.getStartSlot() - t1.getStartSlot() - t1.getLength());
    089            } else if (t2.getStartSlot() + t2.getLength() <= t1.getStartSlot()) {
    090                return Placement.getDistanceInMinutes(m, p1, p2) > t2.getBreakTime() + Constants.SLOT_LENGTH_MIN * (t1.getStartSlot() - t2.getStartSlot() - t2.getLength());
    091            }
    092        } else {
    093            if (t1.getStartSlot() + t1.getLength() == t2.getStartSlot()) {
    094                return Placement.getDistanceInMinutes(m, p1, p2) > t1.getBreakTime();
    095            } else if (t2.getStartSlot() + t2.getLength() == t1.getStartSlot()) {
    096                return Placement.getDistanceInMinutes(m, p1, p2) > t2.getBreakTime();
    097            }
    098        }
    099        return false;
    100    }
    101
    102    public static int slots(Placement p1, Placement p2) {
    103        if (p1 == null || p2 == null) return 0;
    104        TimeLocation t1 = p1.getTimeLocation(), t2 = p2.getTimeLocation();
    105        if (t1 == null || t2 == null || !t1.shareDays(t2) || !t1.shareWeeks(t2)) return 0;
    106        return Math.max(t1.getStartSlot() + t1.getLength(), t2.getStartSlot() + t2.getLength()) - Math.min(t1.getStartSlot(), t2.getStartSlot());
    107    }
    108
    109    public static boolean workday(int slotsLimit, Placement p1, Placement p2) {
    110        if (slotsLimit <= 0) return false;
    111        return p1 != null && p2 != null && slots(p1, p2) > slotsLimit;
    112    }
    113
    114    public static boolean ignore(Lecture l1, Lecture l2) {
    115        return l1 != null && l2 != null && l1.isToIgnoreStudentConflictsWith(l2);
    116    }
    117
    118    public static boolean committed(Lecture l1, Lecture l2) {
    119        return l1 != null && l2 != null && (l1.isCommitted() || l2.isCommitted()) && (!l1.isCommitted() || !l2.isCommitted());
    120    }
    121
    122    public static boolean uncommitted(Lecture l1, Lecture l2) {
    123        return l1 != null && l2 != null && !l1.isCommitted() && !l2.isCommitted();
    124    }
    125
    126    public static boolean applicable(Lecture l1, Lecture l2) {
    127        return l1 != null && l2 != null && (!l1.isCommitted() || !l2.isCommitted());
    128    }
    129
    130    public static boolean hard(Lecture l1, Lecture l2) {
    131        return l1 != null && l2 != null && l1.isSingleSection() && l2.isSingleSection() && (!l1.isCommitted() || !l2.isCommitted());
    132    }
    133
    134    public boolean isApplicable(Lecture l1, Lecture l2) {
    135        return l1 != null && l2 != null && !ignore(l1, l2) && uncommitted(l1, l2); // exclude committed and outside student conflicts
    136    }
    137
    138    public boolean isApplicable(Student student, Lecture l1, Lecture l2) {
    139        return isApplicable(l1, l2);
    140    }
    141
    142    public boolean inConflict(Placement p1, Placement p2) {
    143        return overlaps(p1, p2) || distance(getMetrics(), p1, p2);
    144    }
    145
    146    @Override
    147    public double getValue(Assignment<Lecture, Placement> assignment, Placement value, Set<Placement> conflicts) {
    148        double ret = 0.0;
    149        for (JenrlConstraint jenrl: value.variable().jenrlConstraints()) {
    150            Lecture other = jenrl.another(value.variable());
    151            if (!isApplicable(value.variable(), other)) continue;
    152            Placement another = assignment.getValue(other);
    153            if (another == null) continue;
    154            if (conflicts != null && conflicts.contains(another)) continue;
    155            if (inConflict(value, another))
    156                ret += jointEnrollment(jenrl, value, another);
    157        }
    158        if (iIncludeConflicts && conflicts != null)
    159            for (Placement conflict: conflicts) {
    160                for (JenrlConstraint jenrl: conflict.variable().jenrlConstraints()) {
    161                    Lecture other = jenrl.another(conflict.variable());
    162                    if (!isApplicable(conflict.variable(), other)) continue;
    163                    Placement another = assignment.getValue(other);
    164                    if (another == null || another.variable().equals(value.variable())) continue;
    165                    if (conflicts != null && conflicts.contains(another)) continue;
    166                    if (inConflict(conflict, another))
    167                        ret -= jointEnrollment(jenrl, conflict, another);
    168                }
    169            }
    170        return ret;
    171    }
    172
    173    @Override
    174    public double getValue(Assignment<Lecture, Placement> assignment, Collection<Lecture> variables) {
    175        double ret = 0.0;
    176        Set<JenrlConstraint> constraints = new HashSet<JenrlConstraint>();
    177        for (Lecture lect: variables) {
    178            Placement plac = assignment.getValue(lect);
    179            if (plac == null) continue;
    180            for (JenrlConstraint jenrl: lect.jenrlConstraints()) {
    181                if (!constraints.add(jenrl)) continue;
    182                Lecture other = jenrl.another(lect);
    183                if (!other.isCommitted() && !variables.contains(other)) continue;
    184                if (!isApplicable(lect, other)) continue;
    185                if (inConflict(plac, assignment.getValue(other)))
    186                    ret += jointEnrollment(jenrl, plac, assignment.getValue(other));
    187            }
    188        }
    189        return ret;
    190    }
    191
    192    @Override
    193    public double[] getBounds(Assignment<Lecture, Placement> assignment) {
    194        double[] bounds = { 0.0, 0.0 };
    195        for (JenrlConstraint jenrl: ((TimetableModel)getModel()).getJenrlConstraints())
    196            if (isApplicable(jenrl.first(), jenrl.second()))
    197                bounds[0] += jointEnrollment(jenrl);
    198        return bounds;
    199    }
    200
    201    @Override
    202    public double[] getBounds(Assignment<Lecture, Placement> assignment, Collection<Lecture> variables) {
    203        double[] bounds = { 0.0, 0.0 };
    204        Set<JenrlConstraint> constraints = new HashSet<JenrlConstraint>();
    205        for (Lecture lect: variables) {
    206            if (assignment.getValue(lect) == null) continue;
    207            for (JenrlConstraint jenrl: lect.jenrlConstraints()) {
    208                if (isApplicable(jenrl.first(), jenrl.second()) && constraints.add(jenrl) && (jenrl.another(lect).isCommitted() || variables.contains(jenrl.another(lect))))
    209                    bounds[0] += jointEnrollment(jenrl);
    210            }
    211        }
    212        return bounds;
    213    }
    214
    215    public void incJenrl(Assignment<Lecture, Placement> assignment, JenrlConstraint jenrl, double studentWeight, Double conflictPriority, Student student) {
    216        if (isApplicable(jenrl.first(), jenrl.second()) && inConflict(assignment.getValue(jenrl.first()), assignment.getValue(jenrl.second())))
    217            super.inc(assignment, studentWeight);
    218    }
    219
    220    @Override
    221    public void bestRestored(Assignment<Lecture, Placement> assignment) {
    222        super.bestRestored(assignment);
    223        getContext(assignment).setTotal(getValue(assignment, getModel().variables()));
    224    }
    225}