<?php

namespace App\Services\Pacs;

use App\Models\Enums\StudyLevelStatus;
use App\Models\Study;
use Carbon\Carbon;
use Illuminate\Support\Facades\DB;

final class StudyImporter
{
    private array $study_ids = [];

    private array $insert_queue = [];

    private array $update_queue = [];

    private OrthancRestClient $client;

    public function __construct(?OrthancRestClient $client = null)
    {
        $this->client = $client ?? new OrthancRestClient;
    }

    public function scanStudies()
    {
        $this->study_ids = $this->client->getStudiesIds();
    }

    private function checkUpdate(string $orthanc_uid): void
    {
        $row = DB::table('studies')->where('orthanc_uid', $orthanc_uid)->first(['id', 'study_status']);

        if ($row === null) {
            $this->insert_queue[] = $orthanc_uid;

            return;
        }

        if ($row->study_status < StudyLevelStatus::StudyArrived->value) {
            $this->update_queue[$orthanc_uid] = $row->id;
        }
    }

    public function filterStudies()
    {
        $this->insert_queue = [];
        $this->update_queue = [];
        foreach ($this->study_ids as $study_id) {
            $this->checkUpdate($study_id);
        }
    }

    private function fetchStudyDetails(string $orthanc_uid): ?array
    {
        $study = $this->client->getStudyDetails($orthanc_uid);
        if ($study == null) {
            return null;
        }
        $stats = $this->client->getStudyStatistics($orthanc_uid);
        $study['Statistics'] = $stats;

        return $study;
    }

    public function importStudies()
    {
        foreach ($this->update_queue as $orthanc_uid => $row_id) {
            $study = $this->fetchStudyDetails($orthanc_uid);
            if ($study == null) {
                continue;
            }
            $this->updateStudy($row_id, $study);
        }

        foreach ($this->insert_queue as $orthanc_uid) {
            $study = $this->fetchStudyDetails($orthanc_uid);
            if ($study == null) {
                continue;
            }
            $this->insertStudy($study);
        }
    }

    private function prepareData(mixed $study): array
    {
        $inst_name = data_get($study, 'MainDicomTags.InstitutionName');
        $inst_id = InstituteMapper::map($inst_name);

        $data = [
            'orthanc_uid' => strtolower($study['ID']),
            'is_locked' => false,
            'is_active' => true,

            'institution_name' => $inst_name,
            'institute_id' => $inst_id,

            'patient_uid' => $study['ParentPatient'],
            'patient_id' => data_get($study, 'PatientMainDicomTags.PatientID'),
            'patient_name' => data_get($study, 'PatientMainDicomTags.PatientName'),
            'patient_sex' => data_get($study, 'PatientMainDicomTags.PatientSex'),

            'accession_number' => data_get($study, 'MainDicomTags.AccessionNumber'),
            'referring_physician_name' => data_get($study, 'MainDicomTags.ReferringPhysicianName'),
            'study_id' => data_get($study, 'MainDicomTags.StudyID'),
            'study_instance_uid' => data_get($study, 'MainDicomTags.StudyInstanceUID'),
            'study_date' => DicomUtils::dateTimeToCarbon($study['MainDicomTags']['StudyDate'], $study['MainDicomTags']['StudyTime']),
            'receive_date' => Carbon::parse($study['LastUpdate'], 'UTC'),

            'study_modality' => data_get($study, 'RequestedTags.Modality'),
            'body_part_examined' => data_get($study, 'RequestedTags.BodyPartExamined'),
            'software_versions' => data_get($study, 'RequestedTags.SoftwareVersions'),
            'station_name' => data_get($study, 'RequestedTags.StationName'),
            'operators_name' => data_get($study, 'RequestedTags.OperatorsName'),
            'manufacturer' => data_get($study, 'RequestedTags.Manufacturer'),
            'manufacturer_model_name' => data_get($study, 'RequestedTags.ManufacturerModelName'),

            'image_count' => data_get($study, 'Statistics.CountInstances'),
            'series_count' => data_get($study, 'Statistics.CountSeries'),
            'disk_size' => data_get($study, 'Statistics.DiskSize'),
        ];

        if ($study['IsStable']) {
            $data['study_status'] = StudyLevelStatus::StudyArrived->value;
        } else {
            $data['study_status'] = StudyLevelStatus::Pending->value;
        }

        $dob = data_get($study, 'PatientMainDicomTags.PatientBirthDate');
        if (trim($dob) != '') {
            $data['patient_birthdate'] = Carbon::parse($dob);
        }

        $descr = data_get($study, 'MainDicomTags.StudyDescription');
        if ($descr == null) {
            $descr = data_get($study, 'RequestedTags.AcquisitionDeviceProcessingDescription');
        }
        $data['study_description'] = trim($descr);

        return $data;
    }

    public function updateStudy(int $row_id, mixed $study): void
    {
        $data = $this->prepareData($study);
        unset($data['orthanc_uid']);
        Study::where('id', $row_id)->update($data);
    }

    public function insertStudy(mixed $study): void
    {
        $data = $this->prepareData($study);
        Study::create($data);
    }
}