<?php

namespace App\Models;

use CodeIgniter\Model;

class PatientModel extends Model {
  protected $table      = 'patient';
  protected $primaryKey = 'InternalPID';
  protected $allowedFields = ['PatientID', 'AlternatePID', 'Prefix', 'NameFirst', 'NameMiddle', 'NameMaiden', 'NameLast', 'Suffix', 'NameAlias', 'Gender', 'PlaceOfBirth', 'Street_1', 'Street_2', 'Street_3', 
    'City', 'Province', 'ZIP', 'EmailAddress1', 'EmailAddress2', 'Phone', 'MobilePhone', 'Custodian', 'AccountNumber', 'Country', 'Race', 'MaritalStatus', 'Religion', 'Ethnic', 'Citizenship', 
    'DeathIndicator', 'DeathDateTime', 'LinkTo' ]; 
  
  public function getPatients($filters = []) {
    $qname = "LOWER(CONCAT_WS(' ', IFNULL(Prefix,''), IFNULL(NameFirst,''), IFNULL(NameMiddle,''), IFNULL(NameLast,''), IFNULL(NameMaiden,''), IFNULL(Suffix,'')))";

    $builder = $this->db->table($this->table);
    $builder->select("InternalPID, PatientID, $qname as FullName, Gender, Birthdate, EmailAddress1 as Email, MobilePhone");

    if (!empty($filters['Name'])) {
      $rawSql = new RawSql($qname);
      $builder->like($rawSql, $filters['Name'], 'both');
    }

    if (!empty($filters['InternalPID'])) {
      $builder->where('InternalPID', $filters['InternalPID']);
    }

    if (!empty($filters['PatientID'])) {
      $builder->like('PatientID', $filters['PatientID'], 'both');
    }

    if (!empty($filters['Birthdate'])) {
      $builder->where('Birthdate', $filters['Birthdate']);
    }

    return $builder->get()->getResultArray();
  }

  public function getPatient($InternalPID) {
    $rows = $this->db->table('patient p')
      ->select("
          p.*,
          country.VDesc as Country,
          race.VDesc as Race,
          religion.VDesc as Religion,
          ethnic.VDesc as Ethnic,
          patcom.Comment as Comment,
          patidt.IdentifierType,
          patidt.Identifier,
          patatt.Address
      ")
      ->join('valueset country', 'country.VID = p.Country', 'left')
      ->join('valueset race', 'race.VID = p.Race', 'left')
      ->join('valueset religion', 'religion.VID = p.Religion', 'left')
      ->join('valueset ethnic', 'ethnic.VID = p.Ethnic', 'left')
      ->join('patcom', 'patcom.InternalPID = p.InternalPID', 'left')
      ->join('patidt', 'patidt.InternalPID = p.InternalPID', 'left')
      ->join('patatt', 'patatt.InternalPID = p.InternalPID and patatt.DelDate is null', 'left')
      ->where('p.InternalPID', (int) $InternalPID)
      ->get()
      ->getResultArray();

    if (empty($rows)) { return null; }

    $patient = $rows[0];

    if (method_exists($this, 'transformPatientData')) { $patient = $this->transformPatientData($patient); }

    // Default nested structures
    $patient['Identity']    = null;
    $patient['Attachments'] = [];

    foreach ($rows as $row) {
      if ($row['IdentifierType'] && $row['Identifier'] && !$patient['Identity']) {
        $patient['Identity'] = [
          'IdentifierType' => $row['IdentifierType'],
          'Identifier'     => $row['Identifier'],
        ];
      }

      if ($row['Address']) {
        $patient['Attachments'][] = ['Address' => $row['Address']];
      }
    }

    if (empty($patient['Identity'])) { $patient['Identity'] = null; }
    if (empty($patient['Attachments'])) { $patient['Attachments'] = null; }

    return $patient;
  }

  public function createPatient($input) {
    $db = \Config\Database::connect();
    $patidt      = $input['patidt']  ?? [];
    $patatt      = $input['patatt']  ?? [];
    $patcom      = $input['patcom']  ?? [];
    try {
      $db->transStart();
      
      $this->insert($input);
      $newInternalPID = $this->getInsertID();

      if (!empty($patidt)) {
        $patidt['InternalPID'] = $newInternalPID;
        $db->table('patidt')->insert($patidt);
      }

      if (!empty($patatt)) {
        foreach ($patatt as &$row) {
          $row['InternalPID'] = $newInternalPID;
        }
        $db->table('patatt')->upsertBatch($patatt);
      }

      if (!empty($patcom['Comment'])) {
        $patcom['InternalPID'] = $newInternalPID;
        $db->table('patcom')->insert($patcom);
      }

      $db->transComplete();

      if ($db->transStatus() === false) {
        $error = $db->error();
        throw new \Exception('Transaction failed: ' . ($error['message'] ?? 'Unknown DB error'));
      }

      return $newInternalPID;
    } catch (\Exception $e) {
        $db->transRollback();
        throw $e; // rethrow so controller can handle response
    }
  }

  private function transformPatientData(array $patient): array {
    $patient["Age"] = $this->calculateAgeFromBirthdate($patient["Birthdate"]);
    $patient["Birthdate"] = $this->formatedDate($patient["Birthdate"]);
    $patient["CreateDate"] = $this->formatedDate($patient["CreateDate"]);
    $patient["DelDate"] = $this->formatedDate($patient["DelDate"]);
    $patient["DeathDateTime"] = $this->formatedDate($patient["DeathDateTime"]);
    $patient["BirthdateConversion"] = $this->formatedDateForDisplay($patient["Birthdate"]);
    $patient["LinkTo"]    = $this->getLinkedPatients($patient['LinkTo']);
    $patient["Custodian"] = $this->getCustodian($patient['Custodian']);

    return $patient;
  }


  private function getLinkedPatients(?string $linkTo): ?array {
    if (empty($linkTo)) { return null; }

    $ids = array_filter(explode(',', $linkTo));

    return $this->db->table('patient')
      ->select('InternalPID, PatientID')
      ->whereIn('InternalPID', $ids)
      ->get()
      ->getResultArray() ?: null;
  }

  private function getCustodian($custodianId): ?array {
    if (empty($custodianId)) {
      return null;
    }

    return $this->db->table('patient')
      ->select('InternalPID, PatientID')
      ->where('InternalPID', (int) $custodianId)
      ->get()
      ->getRowArray() ?: null;
  }

  // Conversion to (Years Months Days)
  private function calculateAgeFromBirthdate($birthdate) {
    $dob = new \DateTime($birthdate);
    $today = new \DateTime();
    $diff = $today->diff($dob);

    $formattedAge = "";
    if ($diff->y > 0){
      $formattedAge .= "{$diff->y} Years ";
    }
    if ($diff->m > 0){
      $formattedAge .= "{$diff->m} Months ";
    }
    if ($diff->d > 0){
      $formattedAge .= "{$diff->d} Days";
    }

    return $formattedAge;
  }

  // Conversion Time to Format Y-m-d H:i
  private function formatedDate($dateString) {
    $date = \DateTime::createFromFormat('Y-m-d H:i', $dateString);

    if (!$date) {
      $timestamp = strtotime($dateString);
      if ($timestamp) {
        return date('Y-m-d H:i', $timestamp);
      }
      return null;
    }

    return $date->format('Y-m-d H:i');
  }

  // Conversion Time to Format j M Y
  private function formatedDateForDisplay($dateString) {    
    $date = \DateTime::createFromFormat('Y-m-d H:i', $dateString);

    if (!$date) {
      $timestamp = strtotime($dateString);
      if ($timestamp) {
        return date('j M Y', $timestamp);
      }
      return null;
    }

    return $date->format('j M Y');
  }

}