package net.sourceforge.fenixedu.domain;

import java.util.ArrayList;
import java.util.Comparator;
import java.util.List;

import net.sourceforge.fenixedu.domain.student.Registration;
import net.sourceforge.fenixedu.domain.student.Student;

import org.apache.commons.beanutils.BeanComparator;
import org.joda.time.DateTimeFieldType;
import org.joda.time.LocalDate;
import org.joda.time.Partial;
import org.joda.time.YearMonthDay;

public class Tutorship extends Tutorship_Base {

    public static final Comparator<Tutorship> TUTORSHIP_COMPARATOR_BY_STUDENT_NUMBER = new BeanComparator(
	    "studentCurricularPlan.registration.number");

    public static final Comparator<Tutorship> TUTORSHIP_COMPARATOR_BY_ENTRY_YEAR = new BeanComparator(
	    "studentCurricularPlan.registration.startDate");

    public static Comparator<Tutorship> TUTORSHIP_END_DATE_COMPARATOR = new Comparator<Tutorship>() {
	public int compare(Tutorship t1, Tutorship t2) {
	    if (t1.getEndDate() == null) {
		return -1;
	    } else if (t2.getEndDate() == null) {
		return 1;
	    } else {
		return (t1.getEndDate().isBefore(t2.getEndDate()) ? -1 : (t1.getEndDate().isAfter(t2.getEndDate()) ? 1 : (t1
			.getIdInternal() <= t2.getIdInternal()) ? -1 : 1));
	    }
	}
    };

    public static Comparator<Tutorship> TUTORSHIP_START_DATE_COMPARATOR = new Comparator<Tutorship>() {
	public int compare(Tutorship t1, Tutorship t2) {
	    if (t1.getStartDate() == null) {
		return -1;
	    } else if (t2.getStartDate() == null) {
		return 1;
	    } else {
		return (t1.getStartDate().isBefore(t2.getStartDate()) ? -1 : (t1.getStartDate().isAfter(t2.getStartDate()) ? 1
			: (t1.getIdInternal() <= t2.getIdInternal()) ? -1 : 1));
	    }
	}
    };

    // Tutorship maximum period, in years
    public static final int TUTORSHIP_MAX_PERIOD = 2;

    public Tutorship(Teacher teacher, Partial tutorshipStartDate, Partial tutorshipEndDate) {
	super();

	setRootDomainObject(RootDomainObject.getInstance());
	setTeacher(teacher);
	setStartDate(tutorshipStartDate);
	setEndDate(tutorshipEndDate);
    }

    public void delete() {
	removeStudentCurricularPlan();
	removeTeacher();
	removeRootDomainObject();
	super.deleteDomainObject();
    }

    public boolean hasEndDate() {
	if (getEndDate() != null)
	    return true;
	return false;
    }

    public boolean isActive() {
	if (!this.hasEndDate())
	    return false;

	YearMonthDay currentYearMonthDay = new YearMonthDay();
	Partial currentDate = new Partial(new DateTimeFieldType[] { DateTimeFieldType.year(), DateTimeFieldType.monthOfYear() },
		new int[] { currentYearMonthDay.year().get(), currentYearMonthDay.monthOfYear().get() });

	if (getEndDate().isAfter(currentDate)) {
	    return true;
	}

	return false;
    }

    public static int getLastPossibleTutorshipYear() {
	YearMonthDay currentDate = new YearMonthDay();
	return currentDate.getYear() + TUTORSHIP_MAX_PERIOD;
    }

    public Registration getStudent() {
	return this.getStudentCurricularPlan().getRegistration();
    }

    public boolean belongsToAnotherTeacher() {
	Student student = this.getStudentCurricularPlan().getRegistration().getStudent();
	Registration registration = student.getLastActiveRegistration();

	if (registration == null)
	    return false;

	Tutorship lastTutorship = registration.getActiveStudentCurricularPlan().getLastTutorship();

	if (lastTutorship != null && !lastTutorship.equals(this))
	    return true;

	return false;
    }

    public static List<Tutorship> getStudentActiveTutorships(Integer studentNumber) {
	List<Tutorship> tutorships = new ArrayList<Tutorship>();
	for (Tutorship t : RootDomainObject.getInstance().getTutorships()) {
	    if (t.getStudent().getNumber().equals(studentNumber) && t.isActive()) {
		tutorships.add(t);
	    }
	}
	return tutorships;
    }

    public List<ExecutionYear> getCoveredExecutionYears() {
	return ExecutionYear.readExecutionYears(getStartDateExecutionYear(), getEndDateExecutionYear());
    }

    private ExecutionYear getStartDateExecutionYear() {
	int year = getStartDate().get(DateTimeFieldType.year());
	int month = getStartDate().get(DateTimeFieldType.monthOfYear());
	return ExecutionYear.readByDateTime(new LocalDate(year, month, 1).toDateTimeAtCurrentTime());
    }

    private ExecutionYear getEndDateExecutionYear() {
	int year = getEndDate().get(DateTimeFieldType.year());
	int month = getEndDate().get(DateTimeFieldType.monthOfYear());
	return ExecutionYear.readByDateTime(new LocalDate(year, month, 1).toDateTimeAtCurrentTime());
    }
}