package com.mirna.hospitalmanagementapi.application.services;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.mirna.hospitalmanagementapi.application.usecase.consultation.FindConsultationByIdUseCase;
import com.mirna.hospitalmanagementapi.application.usecase.consultation.SaveConsultationUseCase;
import com.mirna.hospitalmanagementapi.application.usecase.doctor.FindDoctorByIdUseCase;
import com.mirna.hospitalmanagementapi.application.usecase.doctor.FindOneFreeDoctorBySpecialtyUseCase;
import com.mirna.hospitalmanagementapi.application.usecase.patient.FindPatientByIdUseCase;
import com.mirna.hospitalmanagementapi.domain.dtos.consultation.ConsultationCanceledDTO;
import com.mirna.hospitalmanagementapi.domain.dtos.consultation.ConsultationDTO;
import com.mirna.hospitalmanagementapi.domain.entities.Consultation;
import com.mirna.hospitalmanagementapi.domain.entities.Doctor;
import com.mirna.hospitalmanagementapi.domain.entities.Patient;
import com.mirna.hospitalmanagementapi.domain.exceptions.ConsultationValidationException;
import com.mirna.hospitalmanagementapi.domain.services.ConsultationService;
import com.mirna.hospitalmanagementapi.domain.services.DoctorScheduleService;
import com.mirna.hospitalmanagementapi.domain.repositories.ConsultationRepository;

import jakarta.persistence.EntityNotFoundException;
import java.time.LocalTime;
import java.time.OffsetDateTime;
import java.time.ZoneOffset;

import org.springframework.transaction.annotation.Transactional;

@Service
public class ConsultationServiceImpl implements ConsultationService {

    @Autowired
    private SaveConsultationUseCase saveConsultation;

    @Autowired
    private FindConsultationByIdUseCase findConsultationById;

    @Autowired
    private ConsultationRepository consultationRepository;

    @Autowired
    private FindPatientByIdUseCase findPatientById;

    @Autowired
    private FindDoctorByIdUseCase findDoctorById;

    @Autowired
    private FindOneFreeDoctorBySpecialtyUseCase findOneFreeDoctorBySpecialty;

    @Autowired
    private DoctorScheduleService doctorScheduleService;

    private static final ZoneOffset BANGKOK_ZONE_OFFSET = ZoneOffset.ofHours(7);

    @Override
    @Transactional
    public Consultation addConsultation(ConsultationDTO consultationDTO) throws ConsultationValidationException {
        Patient patient = validatePatient(consultationDTO.patientId(), consultationDTO.consultationDate());
        Doctor doctor = validateAndFindDoctor(consultationDTO);
        validatePatientAndDoctorAvailability(patient, doctor, consultationDTO.consultationDate());

        Consultation consultation = new Consultation(patient, doctor, consultationDTO.consultationDate());

        return saveConsultation.execute(consultation);
    }

    private Patient validatePatient(Long patientId, OffsetDateTime consultationDate) throws ConsultationValidationException {
        if (patientId == null) {
            throw new ConsultationValidationException("Patient ID cannot be null");
        }

        Patient patient = findPatientById.execute(patientId);

        if (patient == null) {
            throw new ConsultationValidationException("This patient is not found");
        }
        if (!patient.getActive()) {
            throw new ConsultationValidationException("This patient is not active");
        }

        OffsetDateTime consultationDateInBkkZone = consultationDate.withOffsetSameInstant(BANGKOK_ZONE_OFFSET);
        OffsetDateTime startOfDay = consultationDateInBkkZone.with(LocalTime.MIN);
        OffsetDateTime endOfDay = consultationDateInBkkZone.with(LocalTime.MAX);

        // แก้ไขบรรทัดนี้: ส่งพารามิเตอร์ที่ถูกต้องไปยัง Repository
        if (consultationRepository.findConsultationByPatientAndDate(patient.getId(), startOfDay, endOfDay) != null) {
            throw new ConsultationValidationException("This patient is not free on this date");
        }
        return patient;
    }

    private Doctor validateAndFindDoctor(ConsultationDTO consultationDTO) throws ConsultationValidationException {
        Doctor doctor = null;
        OffsetDateTime consultationDateInBkkZone = consultationDTO.consultationDate().withOffsetSameInstant(BANGKOK_ZONE_OFFSET);

        if (consultationDTO.doctorId() != null) {
            doctor = findDoctorById.execute(consultationDTO.doctorId());
        } else if (consultationDTO.specialty() != null) {
            doctor = findOneFreeDoctorBySpecialty.execute(consultationDTO.specialty(), consultationDateInBkkZone);
        } else {
            throw new ConsultationValidationException("At least the specialty or doctor ID must be filled in");
        }

        if (doctor == null) {
            throw new ConsultationValidationException("No doctors found at the requested time or specialty.");
        }
        return doctor;
    }

    private void validatePatientAndDoctorAvailability(Patient patient, Doctor doctor, OffsetDateTime consultationDate) throws ConsultationValidationException {
        OffsetDateTime consultationDateInBkkZone = consultationDate.withOffsetSameInstant(BANGKOK_ZONE_OFFSET);

        OffsetDateTime startOfDay = consultationDateInBkkZone.with(LocalTime.MIN);
        OffsetDateTime endOfDay = consultationDateInBkkZone.with(LocalTime.MAX);

        // แก้ไขบรรทัดนี้: ส่งพารามิเตอร์ที่ถูกต้องไปยัง Repository
        if (consultationRepository.findConsultationByDoctorAndDate(doctor.getId(), startOfDay, endOfDay) != null) {
            throw new ConsultationValidationException("This doctor is not free on this date");
        }

        boolean isDoctorAvailable = doctorScheduleService.isDoctorAvailable(
                doctor.getId(),
                consultationDateInBkkZone.getDayOfWeek(),
                consultationDateInBkkZone.toLocalTime()
        );

        if (!isDoctorAvailable) {
            throw new ConsultationValidationException("The selected doctor is not on duty at the requested time.");
        }
    }

    @Override
    public Consultation findConsultationById(Long id) {
        Consultation consultation = findConsultationById.execute(id);

        if (consultation == null)
            throw new EntityNotFoundException("No existing consultation with this id");

        return consultation;
    }

    @Override
    public Consultation cancelConsultation(ConsultationCanceledDTO consultationCanceledDTO) {
        Consultation consultation = this.findConsultationById(consultationCanceledDTO.consultationId());
        consultation.setCanceled(true);
        consultation.setReasonCancellation(consultationCanceledDTO.reasonCancellation());
        return saveConsultation.execute(consultation);
    }
}