<?php

namespace App\Services\Payments\Danal\Gateways;

use App\Models\GcPaymentAttempt;
use App\Support\DanalAes256CbcHex;

final class DanalCardGateway
{
    public function __construct(
        private readonly DanalAes256CbcHex $aes,
    ) {}

    /**
     * CI3: payment_danal_card() -> AUTH
     * return: redirect form info
     */
    public function auth(GcPaymentAttempt $attempt, string $token, array $order, string $cardKind = 'general'): array
    {
        $cfg = config("danal.card.$cardKind");
        if (!$cfg || empty($cfg['cpid']) || empty($cfg['key']) || empty($cfg['iv']) || empty($cfg['url'])) {
            throw new \RuntimeException("Danal card config missing: $cardKind");
        }

        $oid = (string)($order['oid'] ?? '');
        $amount = (int)($order['amount'] ?? $order['pay_money'] ?? 0);
        $itemName = (string)($order['itemName'] ?? $order['pin_name'] ?? '상품권');

        $isMobile = (bool)($order['is_mobile'] ?? false);
        $userAgent = $isMobile ? 'WM' : 'PC';

        // Return/Cancel: token을 query로 붙여서 세션 의존 제거
        $returnUrl = route('web.payments.danal.card.return', ['o' => $oid, 't' => $token], true);
        $cancelUrl = route('web.payments.danal.cancel',     ['o' => $oid, 't' => $token], true);

        // BYPASSVALUE는 '&' 금지(다날 주의) → ; 구분
        $bypass = "TOKEN={$token};OID={$oid};AMOUNT={$amount};";

        $req = [
            'SUBCPID'     => '',
            'AMOUNT'      => (string)$amount,
            'CURRENCY'    => '410',
            'ITEMNAME'    => $this->toEucKr($itemName),
            'USERAGENT'   => $userAgent,
            'ORDERID'     => $oid,
            'OFFERPERIOD' => '',

            'USERNAME'  => '',
            'USERID'    => (string)($order['mem_no'] ?? ''),
            'USEREMAIL' => '',

            'CANCELURL' => $cancelUrl,
            'RETURNURL' => $returnUrl,

            'TXTYPE'      => 'AUTH',
            'SERVICETYPE' => 'DANALCARD',
            'ISNOTI'      => 'N',
            'BYPASSVALUE' => $bypass,
        ];

        $attempt->card_kind = $cardKind;
        $attempt->request_payload = $req;
        $attempt->save();

        $res = $this->postCpcgi(
            (string)$cfg['url'],
            (string)$cfg['cpid'],
            $req,
            (string)$cfg['key'],
            (string)$cfg['iv']
        );

        $attempt->response_payload = $res;
        $attempt->save();

        if (($res['RETURNCODE'] ?? '') !== '0000') {
            $msg = (string)($res['RETURNMSG'] ?? '모듈 호출 실패');
            throw new \RuntimeException("Danal card AUTH failed: {$res['RETURNCODE']} {$msg}");
        }

        return [
            'actionUrl' => (string)$res['STARTURL'],
            'params' => [
                'STARTPARAMS' => (string)$res['STARTPARAMS'],
            ],
            'acceptCharset' => 'EUC-KR',
        ];
    }

    /**
     * CI3: payment_danal_card_return() -> RETURN decrypt -> BILL
     * return: result view payload
     */
    public function billOnReturn(GcPaymentAttempt $attempt, string $token, array $order, array $post): array
    {
        $cardKind = $attempt->card_kind ?: 'general';
        $cfg = config("danal.card.$cardKind");
        if (!$cfg || empty($cfg['cpid']) || empty($cfg['key']) || empty($cfg['iv']) || empty($cfg['url'])) {
            throw new \RuntimeException("Danal card config missing: $cardKind");
        }

        $oid = (string)($order['oid'] ?? $attempt->oid);
        $amount = (int)($order['amount'] ?? $order['pay_money'] ?? $attempt->amount ?? 0);

        $returnParams = (string)($post['RETURNPARAMS'] ?? '');
        if ($returnParams === '') {
            return $this->fail('C990', 'RETURNPARAMS 누락');
        }

        // RETURNPARAMS 복호화
        $retStr = $this->aes->decrypt($returnParams, (string)$cfg['key'], (string)$cfg['iv']);
        $retMap = $this->aes->parseQuery($retStr);

        // 주문번호 일치 검증
        if (($retMap['ORDERID'] ?? '') !== $oid) {
            return $this->fail('C991', '주문번호 불일치');
        }

        // 인증 결과 확인
        $retCode = (string)($retMap['RETURNCODE'] ?? '');
        $retMsg  = (string)($retMap['RETURNMSG'] ?? '');

        if ($retCode !== '0000') {
            return $this->fail($retCode ?: 'C992', $retMsg ?: '카드 인증 실패');
        }

        // BILL 요청
        $billReq = [
            'TID'         => (string)($retMap['TID'] ?? ''),
            'AMOUNT'      => (string)$amount,
            'TXTYPE'      => 'BILL',
            'SERVICETYPE' => 'DANALCARD',
        ];

        $res = $this->postCpcgi(
            (string)$cfg['url'],
            (string)$cfg['cpid'],
            $billReq,
            (string)$cfg['key'],
            (string)$cfg['iv']
        );

        $res = $this->eucKrArrayToUtf8($res);

        if (($res['RETURNCODE'] ?? '') === '0000') {
            $attempt->status = 'paid';
            $attempt->pg_tid = (string)($res['TID'] ?? '');
            $attempt->return_code = (string)($res['RETURNCODE'] ?? '');
            $attempt->return_msg = (string)($res['RETURNMSG'] ?? '');
            $attempt->returned_at = now();
            $attempt->return_payload = ['ret' => $retMap, 'bill' => $res];
            $attempt->save();

            return [
                'status' => 'success',
                'message' => '결제가 완료되었습니다.',
                'redirectUrl' => url('/mypage/usage'),
                // 필요하면 아래를 서비스에서 order_complete에 사용
                'meta' => [
                    'oid' => $oid,
                    'tid' => (string)($res['TID'] ?? ''),
                    'amount' => (int)($res['AMOUNT'] ?? $amount),
                    'code' => (string)($res['RETURNCODE'] ?? ''),
                    'msg'  => (string)($res['RETURNMSG'] ?? ''),
                    'ret_data' => $res,
                ],
            ];
        }

        $msg = (string)($res['RETURNMSG'] ?? '카드 결제 실패');
        return $this->fail((string)($res['RETURNCODE'] ?? 'C993'), $msg);
    }

    private function postCpcgi(string $url, string $outerCpid, array $reqData, string $hexKey, string $hexIv): array
    {
        // CI3 CallCredit/CallVAccount 규칙 그대로:
        // data2str -> AES -> base64 -> urlencode -> CPID=...&DATA=...
        $plain = $this->aes->buildQuery($reqData);
        $enc = $this->aes->encrypt($plain, $hexKey, $hexIv);
        $payload = 'CPID=' . $outerCpid . '&DATA=' . urlencode($enc);

        $ch = curl_init();
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
        curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, (int)config('danal.authtel.connect_timeout', 5));
        curl_setopt($ch, CURLOPT_TIMEOUT, (int)config('danal.authtel.timeout', 30));
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_HTTPHEADER, ["Content-type:application/x-www-form-urlencoded; charset=euc-kr"]);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $payload);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

        $resStr = curl_exec($ch);

        if (($errno = curl_errno($ch)) !== 0) {
            $err = curl_error($ch);
            curl_close($ch);
            return [
                'RETURNCODE' => 'E_NETWORK',
                'RETURNMSG' => "NETWORK({$errno}:{$err})",
            ];
        }

        curl_close($ch);

        $resMap = $this->aes->parseQuery((string)$resStr);
        if (isset($resMap['DATA'])) {
            $dec = $this->aes->decrypt((string)$resMap['DATA'], $hexKey, $hexIv);
            $resMap = $this->aes->parseQuery($dec);
        }

        return $resMap;
    }

    private function toEucKr(string $s): string
    {
        if ($s === '') return '';
        $out = @iconv('UTF-8', 'EUC-KR//IGNORE', $s);
        return $out === false ? $s : $out;
    }

    private function eucKrArrayToUtf8(array $arr): array
    {
        foreach ($arr as $k => $v) {
            if (!is_string($v) || $v === '') continue;
            $u = @iconv('EUC-KR', 'UTF-8//IGNORE', $v);
            if ($u !== false) $arr[$k] = $u;
        }
        return $arr;
    }

    private function fail(string $code, string $msg): array
    {
        return [
            'status' => 'fail',
            'message' => $msg ?: '결제에 실패했습니다.',
            'redirectUrl' => url('/mypage/usage'),
            'meta' => [
                'code' => $code,
                'msg' => $msg,
            ],
        ];
    }
}