Convert mysql to doctrine - mysql

Question

I have the following MySQL query
select a.*, d.*, p.*, pow.* from appointment a
left join doctor d on d.id = a.doctor_id
left join patient p on p.id = a.patient_id
left join point_of_work pow on pow.id = a.point_of_work_id
where (doctor_id, patient_id, date) = (
select doctor_id, patient_id,
coalesce(
min(case when date > curdate() then date end),
max(case when date < curdate() then date end)
) date
from appointment
where (doctor_id, patient_id) = (a.doctor_id, a.patient_id)
)
and d.external_id = 1
And I am trying to convert it to DQL.
Right now I come to this version of DQL but it seems I'am doing something (or maybe more things:( wrong)
$expr = $this->getEntityManager()->getExpressionBuilder();
$queryBuilder = $this->createQueryBuilder('a')
->leftJoin(Doctor::class, 'd')
->leftJoin(Patient::class, 'p')
->leftJoin(PointOfWork::class, 'pow')
->where(
$expr->eq('doctorId, patient_id, date',
$this->createQueryBuilder('a')
->select(Appointment::class . ',
coalesce(
min(case when date > curdate() then date end),
max(case when date < curdate() then date end)
) date'
)
->where ('(doctorId, patientId) = (a.doctorId, a.patientId)')
)
)
->andWhere('d.externalId = :externalId')
->setParameter('externalId', $doctorExternalId)
->setMaxResults($limit)
->setFirstResult($offset);
What approaches do I need for the DQL conversion?