package net.sourceforge.fenixedu.applicationTier.Servico.departmentAdmOffice;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;

import net.sourceforge.fenixedu.applicationTier.Service;
import net.sourceforge.fenixedu.applicationTier.Servico.exceptions.FenixServiceException;
import net.sourceforge.fenixedu.domain.CurricularCourse;
import net.sourceforge.fenixedu.domain.CurricularYear;
import net.sourceforge.fenixedu.domain.ExecutionDegree;
import net.sourceforge.fenixedu.domain.SchoolClass;
import net.sourceforge.fenixedu.domain.degree.DegreeType;
import net.sourceforge.fenixedu.domain.student.Registration;
import net.sourceforge.fenixedu.domain.student.SearchStudentsWithEnrolmentsByParameters;
import net.sourceforge.fenixedu.persistenceTier.ExcepcaoPersistencia;
import net.sourceforge.fenixedu.util.StringUtils;

/**
 * 
 * @author cssro
 * 
 */
public class ReadStudentsByParameters extends Service {

    protected static final Comparator<Registration> REGISTRATION_NAME_COMPARATOR = new Comparator<Registration>() {
	public int compare(final Registration o1, final Registration o2) {
	    return StringUtils.normalize(o1.getPerson().getName()).compareTo(StringUtils.normalize(o2.getPerson().getName()));
	};
    };

    public Set<Registration> run(SearchStudentsWithEnrolmentsByParameters bean) throws FenixServiceException, ExcepcaoPersistencia {
	Set<Registration> result = new HashSet<Registration>();

	if (bean.getExecutionYear() == null) {
	    return Collections.<Registration> emptySet();
	}

	if (bean.getDegree() != null) {
	    for (final ExecutionDegree executionDegree : bean.getDegree().getExecutionDegreesForExecutionYear(
		    bean.getExecutionYear())) {
		result.addAll(executionDegree.getActiveRegistrationsForDegree());
	    }
	} else {
	    final List<DegreeType> degreeTypes = new ArrayList<DegreeType>();
	    degreeTypes.add(DegreeType.DEGREE);
	    degreeTypes.add(DegreeType.BOLONHA_DEGREE);
	    degreeTypes.add(DegreeType.BOLONHA_INTEGRATED_MASTER_DEGREE);

	    for (final ExecutionDegree executionDegree : bean.getExecutionYear().getExecutionDegreesByTypes(degreeTypes)) {
		result.addAll(executionDegree.getActiveRegistrationsForDegree());
	    }
	}

	return filter(bean, result);
    }

    private Set<Registration> filter(SearchStudentsWithEnrolmentsByParameters bean, Set<Registration> registrations) {
	final Set<Registration> result = new TreeSet<Registration>(REGISTRATION_NAME_COMPARATOR);
	for (final Registration registration : registrations) {
	    if (evaluateParameters(bean, registration)) {
		result.add(registration);
	    }
	}
	return result;
    }

    private boolean evaluateParameters(SearchStudentsWithEnrolmentsByParameters bean, Registration registration) {
	return evaluateCurricularCourse(bean, registration) && evaluateSchoolClass(bean, registration) &&
		evaluateCurricularYear(bean, registration);

    }

    private boolean evaluateCurricularCourse(SearchStudentsWithEnrolmentsByParameters bean, Registration registration) {
	final CurricularCourse curricularCourse = bean.getCurricularCourse();
	if (curricularCourse == null) {
	    return true;
	} else if (registration.hasActiveEnrollment(curricularCourse, bean.getExecutionYear())) {
	    return true;
	}

	return false;
    }
    
    private boolean evaluateSchoolClass(SearchStudentsWithEnrolmentsByParameters bean, Registration registration) {
	final SchoolClass schoolClass = bean.getSchoolClass();
	final SchoolClass schoolClassReg = registration.getSchoolClassByExecutionYear(bean.getExecutionYear());
	if (schoolClass == null) {
	    return true;
	} else if (schoolClassReg != null && schoolClassReg == schoolClass) {
	    return true;
	}

	return false;
    }
    
    private boolean evaluateCurricularYear(SearchStudentsWithEnrolmentsByParameters bean, Registration registration) {
	CurricularYear curricularYear = bean.getCurricularYear();
	if (curricularYear == null) {
	    return true;
	} else if (registration.getCurricularYear(bean.getExecutionYear()) == curricularYear.getYear()) {
	    return true;
	}
	return false;
    }

    
}