001package org.cpsolver.instructor.model;
002
003import org.cpsolver.ifs.assignment.Assignment;
004import org.cpsolver.ifs.criteria.Criterion;
005import org.cpsolver.ifs.model.Value;
006
007/**
008 * Teaching assignment. An assignment of an instructor to a teaching request (a set of sections of a course).
009 * A teaching assignment also contains the value of attribute, instructor, course, and time preferences. 
010 * 
011 * @author  Tomáš Müller
012 * @version IFS 1.3 (Instructor Sectioning)<br>
013 *          Copyright (C) 2016 Tomáš Müller<br>
014 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
015 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
016 * <br>
017 *          This library is free software; you can redistribute it and/or modify
018 *          it under the terms of the GNU Lesser General Public License as
019 *          published by the Free Software Foundation; either version 3 of the
020 *          License, or (at your option) any later version. <br>
021 * <br>
022 *          This library is distributed in the hope that it will be useful, but
023 *          WITHOUT ANY WARRANTY; without even the implied warranty of
024 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
025 *          Lesser General Public License for more details. <br>
026 * <br>
027 *          You should have received a copy of the GNU Lesser General Public
028 *          License along with this library; if not see
029 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
030 */
031public class TeachingAssignment extends Value<TeachingRequest.Variable, TeachingAssignment> {
032    private Instructor iInstructor;
033    private int iHashCode;
034    private int iAttributePreference, iInstructorPreference, iCoursePreference, iTimePreference;
035
036    /**
037     * Constructor
038     * @param variable teaching request variable
039     * @param instructor instructor (it is expected that {@link Instructor#canTeach(TeachingRequest)} is true and that {@link TeachingRequest#getAttributePreference(Instructor)} is not prohibited)
040     * @param attributePreference attribute preference (value of {@link TeachingRequest#getAttributePreference(Instructor)})
041     */
042    public TeachingAssignment(TeachingRequest.Variable variable, Instructor instructor, int attributePreference) {
043        super(variable);
044        iInstructor = instructor;
045        iHashCode = variable.hashCode() ^ instructor.hashCode();
046        iTimePreference = instructor.getTimePreference(variable.getRequest()).getPreferenceInt();
047        iCoursePreference = instructor.getCoursePreference(variable.getCourse()).getPreference();
048        iInstructorPreference = variable.getRequest().getInstructorPreference(instructor).getPreference();
049        iAttributePreference = attributePreference;
050    }
051    
052    /**
053     * Constructor
054     * @param variable teaching request variable
055     * @param instructor instructor (it is expected that {@link Instructor#canTeach(TeachingRequest)} is true and that {@link TeachingRequest#getAttributePreference(Instructor)} is not prohibited)
056     */
057    public TeachingAssignment(TeachingRequest.Variable variable, Instructor instructor) {
058        this(variable, instructor, variable.getRequest().getAttributePreference(instructor).getPreferenceInt());
059    }
060
061    /**
062     * Assigned instructor
063     * @return assigned instructor
064     */
065    public Instructor getInstructor() {
066        return iInstructor;
067    }
068    
069    @Override
070    public double toDouble(Assignment<TeachingRequest.Variable, TeachingAssignment> assignment) {
071        double ret = 0.0;
072        for (Criterion<TeachingRequest.Variable, TeachingAssignment> criterion : variable().getModel().getCriteria())
073            ret += criterion.getWeightedValue(assignment, this, null);
074        return ret;
075    }
076
077    @Override
078    public boolean equals(Object o) {
079        if (o == null || !(o instanceof TeachingAssignment))
080            return false;
081        TeachingAssignment a = (TeachingAssignment) o;
082        return variable().equals(a.variable()) && getInstructor().equals(a.getInstructor());
083    }
084    
085    /**
086     * Attribute preference
087     * @return {@link TeachingRequest#getAttributePreference(Instructor)}
088     */
089    public int getAttributePreference() {
090        return iAttributePreference;
091    }
092    
093    /**
094     * Time preference
095     * @return {@link Instructor#getTimePreference(TeachingRequest)}
096     */
097    public int getTimePreference() {
098        return iTimePreference;
099    }
100    
101    /**
102     * Instructor preference
103     * @return {@link TeachingRequest#getInstructorPreference(Instructor) }
104     */
105    public int getInstructorPreference() {
106        return iInstructorPreference;
107    }
108    
109    /**
110     * Course preference
111     * @return {@link Instructor#getCoursePreference(Course)} for {@link TeachingRequest#getCourse()}
112     */
113    public int getCoursePreference() {
114        return iCoursePreference;
115    }
116
117    @Override
118    public int hashCode() {
119        return iHashCode;
120    }
121
122    @Override
123    public String toString() {
124        return variable().getName() + ": " + getInstructor().getName();
125    }
126
127    @Override
128    public String getName() {
129        return (getInstructor().hasName() ? getInstructor().getName() + (getInstructor().hasExternalId() ? " (" + getInstructor().getExternalId() + ")" : "") : getInstructor().getName());
130    }
131}