<?php

namespace App\Services;

use App\DTOs\CollectorDTO;
use App\Entities\CollectorEntity;
use App\Entities\TrafficEntity;
use App\Forms\CollectorForm;
use App\Helpers\CollectorHelper;
use App\Models\CollectorModel;
use CodeIgniter\I18n\Time;
use RuntimeException;

class CollectorService extends CommonService
{
    const OID_IF_IN_OCTETS = '1.3.6.1.2.1.2.2.1.10.'; // ifInOctets (Raw Octets)
    const OID_IF_OUT_OCTETS = '1.3.6.1.2.1.2.2.1.16.'; // ifOutOctets (Raw Octets)
    const SNMP_VERSION = '2c';
    public function __construct(CollectorModel $model)
    {
        parent::__construct($model);
        $this->addClassPaths('Collector');
    }
    public function getFormService(): CollectorForm
    {
        if ($this->formServiceInstance === null) {
            $this->formServiceInstance = new CollectorForm();
            $this->formServiceInstance->setAttributes([
                'pk_field'         => $this->model->getPKField(),
                'title_field'      => $this->model->getTitleField(),
                'table'            => $this->model->getTable(),
                'useAutoIncrement' => $this->model->useAutoIncrement(),
                'class_path' => $this->getClassPaths(false)
            ]);
        }
        return $this->formServiceInstance;
    }
    public function getHelper(): CollectorHelper
    {
        if ($this->helperInstance === null) {
            $this->helperInstance = new CollectorHelper();
            $this->helperInstance->setAttributes([
                'pk_field'         => $this->model->getPKField(),
                'title_field'      => $this->model->getTitleField(),
                'table'            => $this->model->getTable(),
                'useAutoIncrement' => $this->model->useAutoIncrement(),
                'class_path' => $this->getClassPaths(false)
            ]);
        }
        return $this->helperInstance;
    }
    //기본 기능부분
    public function create(object $dto): CollectorEntity
    {
        if (!$dto instanceof CollectorDTO) {
            throw new RuntimeException(__METHOD__ . "에서 오류발생:" . get_class($dto) . "는 사용할수 없습니다.");
        }
        return parent::create($dto);
    }
    public function modify($uid, object $dto): CollectorEntity
    {
        if (!$dto instanceof CollectorDTO) {
            throw new RuntimeException(__METHOD__ . "에서 오류발생:" . get_class($dto) . "는 사용할수 없습니다.");
        }
        return parent::modify($uid, $dto);
    }
    //List 검색용
    //FormFilter 조건절 처리
    //검색어조건절처리
    public function setSearchWord(string $word): void
    {
        $this->model->orLike($this->model->getTable() . "." . $this->model->getTitleField(), $word, 'both');
        parent::setSearchWord($word);
    }
    //SNMP연결
    private function getSNMPOctets(TrafficEntity $trafficEntity, string $oid): ?int
    {
        $fullOid = $oid . $trafficEntity->getInterface();
        $community = $trafficEntity->getCommunity();
        $ip = $trafficEntity->getIP();
        // snmp2_get을 사용하여 SNMP v2c로 요청
        // 💡 snmp2_get() 함수가 존재하지 않는다는 LSP 오류를 무시하기 위해 @suppress 태그 사용
        /** @phpstan-ignore-next-line */
        $result = @snmp2_get($ip, $community, $fullOid, 100000, 3);
        if ($result === false || $result === null) {
            log_message('error', "SNMP 통신 실패: {$ip} ({$fullOid}, Community: {$community})");
            return null;
        }
        // 💡 정규식 수정: /\d+$/ (문자열 끝의 숫자만 추출)
        if (preg_match('/\d+$/', $result, $matches)) {
            // SNMP Counter는 BigInt가 될 수 있으므로 intval 대신 (int) 캐스팅을 사용하여
            // 최대한 큰 정수로 변환합니다. PHP 64비트 환경이 필요합니다.
            return (int)$matches[0];
        }
        return null;
    }
    public function getCalculatedData(TrafficEntity $trafficEntity): array
    {
        $currentInOctets = $this->getSNMPOctets($trafficEntity, self::OID_IF_IN_OCTETS);
        $currentOutOctets = $this->getSNMPOctets($trafficEntity, self::OID_IF_OUT_OCTETS);
        if ($currentInOctets === null || $currentOutOctets === null) {
            $message = "트래픽 수집 실패: {$trafficEntity->getIP()} - IF{$trafficEntity->getInterface()} (UID: {$trafficEntity->getPK()})";
            log_message('warning', $message);
            throw new \Exception($message);
        }
        // 이전 데이터를 조회하여 Rate 계산에 사용
        $lastEntity = $this->model->getLastEntity($trafficEntity->getPK());
        $inKbitsSec = 0;
        $outKbitsSec = 0;
        // 이전 데이터가 있어야만 Rate 계산 가능
        if ($lastEntity !== null) {
            $lastTime = Time::parse($lastEntity->getCreatedAt())->getTimestamp();
            $deltaTime = Time::now()->getTimestamp() - $lastTime;
            if ($deltaTime > 0) {
                // Raw Octets 값의 차분 계산
                $deltaInOctets = $currentInOctets - $lastEntity->getRawIn();
                $deltaOutOctets = $currentOutOctets - $lastEntity->getRawOut();
                // Kbit/s 계산: (Delta_Octets * 8 bits) / Delta_Time_Seconds / 1000 (-> Kbit/s)
                $inKbitsSec = ($deltaInOctets * 8) / $deltaTime / 1000;
                $outKbitsSec = ($deltaOutOctets * 8) / $deltaTime / 1000;
            } else {
                log_message('error', "시간 차이 오류 발생: {$trafficEntity->getIP()} - {$deltaTime}초 (UID: {$trafficEntity->getPK()})");
            }
        }
        // DB에 저장할 데이터를 배열로 반환
        return [
            'trafficinfo_uid' => (int)$trafficEntity->getPK(),
            'in' => (int)$inKbitsSec,
            'out' => (int)$outKbitsSec,
            'raw_in' => (int)$currentInOctets,
            'raw_out' => (int)$currentOutOctets,
        ];
    }
}