/*
 * Created on 07/Set/2003
 *
 */
package net.sourceforge.fenixedu.applicationTier.Servico.student;

import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;

import net.sourceforge.fenixedu.applicationTier.FenixService;
import net.sourceforge.fenixedu.applicationTier.Servico.exceptions.ExistingServiceException;
import net.sourceforge.fenixedu.applicationTier.Servico.exceptions.FenixServiceException;
import net.sourceforge.fenixedu.applicationTier.Servico.exceptions.InvalidArgumentsServiceException;
import net.sourceforge.fenixedu.applicationTier.Servico.exceptions.InvalidChangeServiceException;
import net.sourceforge.fenixedu.applicationTier.Servico.exceptions.InvalidSituationServiceException;
import net.sourceforge.fenixedu.applicationTier.Servico.exceptions.InvalidStudentNumberServiceException;
import net.sourceforge.fenixedu.applicationTier.Servico.exceptions.NotAuthorizedException;
import net.sourceforge.fenixedu.applicationTier.strategy.groupEnrolment.strategys.GroupEnrolmentStrategyFactory;
import net.sourceforge.fenixedu.applicationTier.strategy.groupEnrolment.strategys.IGroupEnrolmentStrategy;
import net.sourceforge.fenixedu.applicationTier.strategy.groupEnrolment.strategys.IGroupEnrolmentStrategyFactory;
import net.sourceforge.fenixedu.domain.Attends;
import net.sourceforge.fenixedu.domain.ExecutionCourse;
import net.sourceforge.fenixedu.domain.Grouping;
import net.sourceforge.fenixedu.domain.Person;
import net.sourceforge.fenixedu.domain.Shift;
import net.sourceforge.fenixedu.domain.StudentGroup;
import net.sourceforge.fenixedu.domain.accessControl.FixedSetGroup;
import net.sourceforge.fenixedu.domain.student.Registration;
import net.sourceforge.fenixedu.domain.util.email.Message;
import net.sourceforge.fenixedu.domain.util.email.Recipient;
import net.sourceforge.fenixedu.domain.util.email.SystemSender;

import org.apache.struts.util.MessageResources;

import pt.ist.fenixWebFramework.security.accessControl.Checked;
import pt.ist.fenixWebFramework.services.Service;

/**
 * @author asnr and scpo
 * 
 */

public class EditGroupShift extends FenixService {

    private static final MessageResources messages = MessageResources.getMessageResources("resources/GlobalResources");

    @Checked("RolePredicates.STUDENT_PREDICATE")
    @Service
    public static Boolean run(Integer studentGroupID, Integer groupingID, Integer newShiftID, String username)
	    throws FenixServiceException {

	final Grouping grouping = rootDomainObject.readGroupingByOID(groupingID);
	if (grouping == null) {
	    throw new ExistingServiceException();
	}

	final StudentGroup studentGroup = rootDomainObject.readStudentGroupByOID(studentGroupID);
	if (studentGroup == null) {
	    throw new InvalidArgumentsServiceException();
	}

	final Shift shift = rootDomainObject.readShiftByOID(newShiftID);
	if (grouping.getShiftType() == null || !shift.containsType(grouping.getShiftType())) {
	    throw new InvalidStudentNumberServiceException();
	}

	final Registration registration = Registration.readByUsername(username);

	IGroupEnrolmentStrategyFactory enrolmentGroupPolicyStrategyFactory = GroupEnrolmentStrategyFactory.getInstance();
	IGroupEnrolmentStrategy strategy = enrolmentGroupPolicyStrategyFactory.getGroupEnrolmentStrategyInstance(grouping);

	if (!strategy.checkStudentInGrouping(grouping, username)) {
	    throw new NotAuthorizedException();
	}

	if (!checkStudentInStudentGroup(registration, studentGroup)) {
	    throw new InvalidSituationServiceException();
	}

	boolean result = strategy.checkNumberOfGroups(grouping, shift);
	if (!result) {
	    throw new InvalidChangeServiceException();
	}
	studentGroup.setShift(shift);

	informStudents(studentGroup, registration, grouping);

	return true;
    }

    private static boolean checkStudentInStudentGroup(Registration registration, StudentGroup studentGroup)
	    throws FenixServiceException {
	boolean found = false;
	List studentGroupAttends = studentGroup.getAttends();
	Attends attend = null;
	Iterator iterStudentGroupAttends = studentGroupAttends.iterator();
	while (iterStudentGroupAttends.hasNext() && !found) {
	    attend = ((Attends) iterStudentGroupAttends.next());
	    if (attend.getRegistration().equals(registration)) {
		found = true;
	    }
	}
	return found;
    }

    private static void informStudents(final StudentGroup studentGroup, final Registration registration, final Grouping grouping) {
	final Set<Person> recievers = new HashSet<Person>();
	for (final Attends attends : studentGroup.getAttends()) {
	    recievers.add(attends.getRegistration().getPerson());
	}

	final StringBuilder executionCourseNames = new StringBuilder();
	for (final ExecutionCourse executionCourse : grouping.getExecutionCourses()) {
	    if (executionCourseNames.length() > 0) {
		executionCourseNames.append(", ");
	    }
	    executionCourseNames.append(executionCourse.getNome());
	}
	final String message = messages.getMessage("message.body.grouping.change.shift", registration.getNumber().toString(),
		studentGroup.getGroupNumber().toString(), executionCourseNames.toString());
	final String groupName = messages.getMessage("message.group.name", studentGroup.getGroupNumber());
	final Collection<Recipient> recipients = Collections
		.singletonList(new Recipient(groupName, new FixedSetGroup(recievers)));

	SystemSender systemSender = rootDomainObject.getSystemSender();
	new Message(systemSender, systemSender.getConcreteReplyTos(), recipients, messages
		.getMessage("message.subject.grouping.change"), message, "");
	// new Email("Fenix System", messages.getMessage("noreply.mail"), null,
	// emails, null, null, messages
	// .getMessage("message.subject.grouping.change"),
	// messages.getMessage("message.body.grouping.change.shift",
	// registration.getNumber().toString(),
	// studentGroup.getGroupNumber().toString()));
    }
}