package net.sourceforge.fenixedu.domain;

import java.util.Collection;
import java.util.UUID;

import net.sourceforge.fenixedu.domain.exceptions.DomainException;
import net.sourceforge.fenixedu.domain.person.RoleType;
import net.sourceforge.fenixedu.domain.student.Registration;
import net.sourceforge.fenixedu.domain.student.Student;

public class AlumniManager {

    public Alumni checkAlumniIdentity(final String documentIdNumber, final String email) {
        Person person = getPerson(documentIdNumber);

        if (person == null) {
            throw new DomainException("error.alumni.person.does.not.exist", documentIdNumber);
        }

        if (!person.hasStudent()) {
            throw new DomainException("error.alumni.person.does.not.have.student.info", documentIdNumber);
        }

        checkRulesToRegisterAlumni(person.getStudent().getNumber(), documentIdNumber);

        final Alumni alumni = getAlumni(person.getStudent().getNumber());

        if (alumni.isRegistered()) {
            throw new DomainException("error.alumni.already.registered");
        }

        alumni.addIfNotExistsEmail(email);
        return alumni;
    }

    private Person getPerson(String documentIdNumber) {
        Collection<Person> personList = Person.readByDocumentIdNumber(documentIdNumber);
        if (personList.size() > 0) {
            return personList.iterator().next();
        }
        return null;
    }

    public Alumni registerAlumni(final Student student) {
        final Alumni alumni = new Alumni(student);
        return alumni;
    }

    public Alumni registerAlumni(final Integer studentNumber, final String documentIdNumber, final String email) {

        checkRulesToRegisterAlumni(studentNumber, documentIdNumber);

        final Alumni alumni = getAlumni(studentNumber);

        if (alumni.isRegistered()) {
            throw new DomainException("error.alumni.already.registered");
        }

        alumni.setUrlRequestToken(UUID.randomUUID());

        alumni.addIfNotExistsEmail(email);

        return alumni;

    }

    private void checkRulesToRegisterAlumni(final Integer studentNumber, final String documentIdNumber) {
        Student student = Student.readStudentByNumber(studentNumber);
        if (student == null) {

            if (Person.findPersonByDocumentID(documentIdNumber).isEmpty()) {
                throw new DomainException("error.person.document.number");
            } else {
                throw new DomainException("error.person.no.student");
            }
        }

        if (!student.getPerson().getDocumentIdNumber().equals(documentIdNumber.trim())) {
            throw new DomainException("error.document.number.student.number.mismatch");
        }

        if (!checkAlumni(student)) {
            if (student.hasAnyRegistrations()) {

                for (Registration registration : student.getRegistrations()) {
                    if (registration.isConcluded()) {
                        return;
                    }
                }

                throw new DomainException("error.no.concluded.registrations");
            } else {
                throw new DomainException("error.no.registrations");
            }
        }
    }

    private boolean checkAlumni(Student alumniStudent) {

        if (alumniStudent.hasAlumni() || alumniStudent.getPerson().hasRole(RoleType.ALUMNI)) {
            return true;
        }

        return false;
    }

    private Alumni getAlumni(final Integer studentNumber) {
        final Student student = Student.readStudentByNumber(studentNumber);
        return student.hasAlumni() ? student.getAlumni() : new Alumni(student);
    }

}