/*
* Copyright 2010 JBoss Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.drools.planner.examples.nurserostering.solver.move.factory;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import java.util.Map;
import org.drools.planner.core.heuristic.selector.move.factory.MoveListFactory;
import org.drools.planner.core.move.CompositeMove;
import org.drools.planner.core.move.Move;
import org.drools.planner.core.solution.Solution;
import org.drools.planner.examples.nurserostering.domain.ShiftAssignment;
import org.drools.planner.examples.nurserostering.domain.Employee;
import org.drools.planner.examples.nurserostering.domain.NurseRoster;
import org.drools.planner.examples.nurserostering.domain.solver.EmployeeWorkSequence;
import org.drools.planner.examples.nurserostering.domain.solver.MovableShiftAssignmentSelectionFilter;
import org.drools.planner.examples.nurserostering.solver.move.EmployeeChangeMove;
public class ShiftAssignmentSequenceSwitchLength2MoveFactory implements MoveListFactory {
private MovableShiftAssignmentSelectionFilter filter = new MovableShiftAssignmentSelectionFilter();
public List<Move> createMoveList(Solution solution) {
NurseRoster nurseRoster = (NurseRoster) solution;
List<Employee> employeeList = nurseRoster.getEmployeeList();
// This code assumes the shiftAssignmentList is sorted
// Filter out every immovable ShiftAssignment
List<ShiftAssignment> shiftAssignmentList = new ArrayList<ShiftAssignment>(
nurseRoster.getShiftAssignmentList());
for (Iterator<ShiftAssignment> it = shiftAssignmentList.iterator(); it.hasNext(); ) {
ShiftAssignment shiftAssignment = it.next();
if (!filter.accept(nurseRoster, shiftAssignment)) {
it.remove();
}
}
// Hash the assignments per employee
Map<Employee, List<AssignmentSequence>> employeeToAssignmentSequenceListMap
= new HashMap<Employee, List<AssignmentSequence>>(employeeList.size());
int assignmentSequenceCapacity = nurseRoster.getShiftDateList().size() + 1 / 2;
for (Employee employee : employeeList) {
employeeToAssignmentSequenceListMap.put(employee,
new ArrayList<AssignmentSequence>(assignmentSequenceCapacity));
}
for (ShiftAssignment shiftAssignment : shiftAssignmentList) {
Employee employee = shiftAssignment.getEmployee();
List<AssignmentSequence> assignmentSequenceList = employeeToAssignmentSequenceListMap.get(employee);
if (assignmentSequenceList.isEmpty()) {
AssignmentSequence assignmentSequence = new AssignmentSequence(shiftAssignment);
assignmentSequenceList.add(assignmentSequence);
} else {
AssignmentSequence lastAssignmentSequence = assignmentSequenceList // getLast()
.get(assignmentSequenceList.size() - 1);
if (lastAssignmentSequence.belongsHere(shiftAssignment)) {
lastAssignmentSequence.add(shiftAssignment);
} else {
AssignmentSequence assignmentSequence = new AssignmentSequence(shiftAssignment);
assignmentSequenceList.add(assignmentSequence);
}
}
}
// The create the move list
List<Move> moveList = new ArrayList<Move>();
// For every 2 distinct employees
for (ListIterator<Employee> leftEmployeeIt = employeeList.listIterator(); leftEmployeeIt.hasNext();) {
Employee leftEmployee = leftEmployeeIt.next();
List<AssignmentSequence> leftAssignmentSequenceList
= employeeToAssignmentSequenceListMap.get(leftEmployee);
for (ListIterator<Employee> rightEmployeeIt = employeeList.listIterator(leftEmployeeIt.nextIndex());
rightEmployeeIt.hasNext();) {
Employee rightEmployee = rightEmployeeIt.next();
List<AssignmentSequence> rightAssignmentSequenceList
= employeeToAssignmentSequenceListMap.get(rightEmployee);
final int SWITCH_LENGTH = 2;
for (AssignmentSequence leftAssignmentSequence : leftAssignmentSequenceList) {
List<ShiftAssignment> leftShiftAssignmentList = leftAssignmentSequence.getShiftAssignmentList();
for (int leftIndex = 0; leftIndex <= leftShiftAssignmentList.size() - SWITCH_LENGTH; leftIndex++) {
for (AssignmentSequence rightAssignmentSequence : rightAssignmentSequenceList) {
List<ShiftAssignment> rightShiftAssignmentList = rightAssignmentSequence.getShiftAssignmentList();
for (int rightIndex = 0; rightIndex <= rightShiftAssignmentList.size() - SWITCH_LENGTH; rightIndex++) {
List<Move> subMoveList = new ArrayList<Move>(SWITCH_LENGTH * 2);
for (ShiftAssignment leftShiftAssignment : leftShiftAssignmentList
.subList(leftIndex, leftIndex + SWITCH_LENGTH)) {
subMoveList.add(new EmployeeChangeMove(leftShiftAssignment, rightEmployee));
}
for (ShiftAssignment rightShiftAssignment : rightShiftAssignmentList
.subList(rightIndex, rightIndex + SWITCH_LENGTH)) {
subMoveList.add(new EmployeeChangeMove(rightShiftAssignment, leftEmployee));
}
moveList.add(new CompositeMove(subMoveList));
}
}
}
}
}
}
return moveList;
}
/**
* TODO DRY with {@link EmployeeWorkSequence}
*/
private static class AssignmentSequence {
private List<ShiftAssignment> shiftAssignmentList;
private int firstDayIndex;
private int lastDayIndex;
private AssignmentSequence(ShiftAssignment shiftAssignment) {
shiftAssignmentList = new ArrayList<ShiftAssignment>();
shiftAssignmentList.add(shiftAssignment);
firstDayIndex = shiftAssignment.getShiftDateDayIndex();
lastDayIndex = firstDayIndex;
}
public List<ShiftAssignment> getShiftAssignmentList() {
return shiftAssignmentList;
}
public int getFirstDayIndex() {
return firstDayIndex;
}
public int getLastDayIndex() {
return lastDayIndex;
}
private void add(ShiftAssignment shiftAssignment) {
shiftAssignmentList.add(shiftAssignment);
int dayIndex = shiftAssignment.getShiftDateDayIndex();
if (dayIndex < lastDayIndex) {
throw new IllegalStateException("The shiftAssignmentList is expected to be sorted by shiftDate.");
}
lastDayIndex = dayIndex;
}
private boolean belongsHere(ShiftAssignment shiftAssignment) {
return shiftAssignment.getShiftDateDayIndex() <= (lastDayIndex + 1);
}
}
}