<?php

namespace App\Providers\Danal\Clients;

use App\Support\Danal\DanalAes256CbcHex;
use App\Support\Danal\Nvp;
use App\Support\Danal\EucKr;
use Illuminate\Support\Facades\Http;

final class DanalCpcgiClient
{
    public function __construct(
        private readonly DanalAes256CbcHex $aes,
        private readonly Nvp $nvp,
        private readonly EucKr $euc,
    ) {}

    /**
     * CPCGI POST 규칙:
     * CPID=...&DATA=urlencode(base64(AES256CBC( key=urlencode(value)&... )))
     * 응답은 NVP, DATA가 있으면 다시 decrypt -> NVP
     */
    public function call(string $url, string $outerCpid, array $reqData, string $hexKey, string $hexIv): array
    {
        $sendData = [];
        foreach ($reqData as $k => $v) {
            $sendData[$k] = is_string($v) ? $this->euc->toEuc($v) : $v;
        }

        $plain = $this->nvp->build($sendData);
        $enc   = $this->aes->encrypt($plain, $hexKey, $hexIv);

        $payload = 'CPID=' . $outerCpid . '&DATA=' . urlencode($enc);

        $httpOpt = config('danal.http');
        $res = Http::withOptions([
            'verify' => (bool)($httpOpt['verify_ssl'] ?? true),
            'connect_timeout' => (float)($httpOpt['connect_timeout'] ?? 5),
        ])
            ->withHeaders([
                'Content-Type' => 'application/x-www-form-urlencoded; charset=euc-kr',
            ])
            ->timeout((int)($httpOpt['timeout'] ?? 30))
            ->withBody($payload, 'application/x-www-form-urlencoded; charset=euc-kr')
            ->post($url);

        $body = (string)$res->body();

        $map = $this->nvp->parse($body);

        // 응답이 DATA를 포함하면 decrypt 후 재파싱
        if (isset($map['DATA']) && is_string($map['DATA']) && $map['DATA'] !== '') {
            $dec = $this->aes->decrypt($map['DATA'], $hexKey, $hexIv);
            $map = $this->nvp->parse($dec);
        }

        // 메시지는 EUC-KR일 수 있으니 UTF-8 변환
        return $this->euc->mapToUtf8($map);
    }

    public function decryptReturnParams(string $returnParams, string $hexKey, string $hexIv): array
    {
        $dec = $this->aes->decrypt($returnParams, $hexKey, $hexIv);
        $map = $this->nvp->parse($dec);
        return $this->euc->mapToUtf8($map);
    }
}