<?php

namespace App\Http\Controllers\Api;

use App\Http\Controllers\Controller;
use App\Http\Requests\Api\RefundRequest;
use App\Models\PaymentTransaction;
use App\Services\Wellnet\WellnetCreditService;
use Illuminate\Http\JsonResponse;
use RuntimeException;

/**
 * 返金コントローラ（API 6）
 */
class RefundController extends Controller
{
    private const REFUND_STATUS_REFUNDED = 'REFUNDED';
    private const REFUND_STATUS_PENDING = 'REFUND_PENDING';

    /**
     * 返金処理
     *
     * POST /api/newwipe/refund
     */
    public function refund(
        RefundRequest $request,
        WellnetCreditService $creditService
    ): JsonResponse {
        $validated = $request->validated();

        // トランザクション検索
        $transaction = PaymentTransaction::where('syuno_recv_num', $validated['SyunoRecvNum'])->first();

        if (!$transaction) {
            return response()->json([
                'error' => [
                    'code' => 'E17',
                    'message' => '対象取引が未入金または存在しません。',
                ]
            ], 400);
        }

        // 入金済みチェック
        if ($transaction->status !== '入金済み') {
            return response()->json([
                'error' => [
                    'code' => 'E17',
                    'message' => '未入金のため返金できません。',
                ]
            ], 400);
        }

        // クレジット決済のみ返金可能
        if ($transaction->payment_type !== 'credit') {
            return response()->json([
                'error' => [
                    'code' => 'INVALID_REQUEST',
                    'message' => 'コンビニ決済の返金はこのAPIでは対応していません。',
                ]
            ], 400);
        }

        // 既に返金済みチェック
        if ($transaction->refund_status === 'REFUNDED') {
            return response()->json([
                'error' => [
                    'code' => 'D01',
                    'message' => '既に返金処理済みです。',
                ]
            ], 400);
        }

        // 決済番号チェック（CAFIS決済番号が必要）
        if (empty($transaction->payment_number)) {
            return response()->json([
                'error' => [
                    'code' => 'E20',
                    'message' => 'クレジット決済番号（paymentNumber）が未取得のため返金できません。',
                ]
            ], 400);
        }

        // 返金額計算
        $refundAmount = $validated['refundAmount'] ?? $transaction->amount;
        $afterRefundPayAmount = $transaction->amount - $refundAmount;

        if ($afterRefundPayAmount < 0) {
            return response()->json([
                'error' => [
                    'code' => 'INVALID_REQUEST',
                    'message' => '返金額が決済金額を超えています。',
                ]
            ], 400);
        }

        $creditResponse = null;
        try {
            // 全額かつ与信取消可能な場合
            if ($afterRefundPayAmount === 0) {
                $creditResponse = $creditService->cancelAuthorize($transaction->payment_number);
            } else {
                // 部分返金（差額返金）
                $creditResponse = $creditService->refund($transaction->payment_number, $afterRefundPayAmount);
            }
        } catch (RuntimeException $e) {
            $mapped = $this->mapCreditExceptionToApiError($e);
            // 与信取消失敗時はrefundで再試行
            if ($afterRefundPayAmount === 0 && str_contains($e->getMessage(), 'INVALID_OPERATION')) {
                try {
                    $creditResponse = $creditService->refund($transaction->payment_number, 0);
                } catch (RuntimeException $retryException) {
                    $retryMapped = $this->mapCreditExceptionToApiError($retryException);
                    return response()->json([
                        'error' => [
                            'code' => $retryMapped['code'],
                            'message' => $retryMapped['message'],
                        ]
                    ], $retryMapped['code'] === 'E99' ? 500 : 400);
                }
            } else {
                return response()->json([
                    'error' => [
                        'code' => $mapped['code'],
                        'message' => $mapped['message'],
                    ]
                ], $mapped['code'] === 'E99' ? 500 : 400);
            }
        }

        // トランザクション更新
        $refundId = 'REF-' . date('YmdHis') . '-' . substr(uniqid(), -6);
        $refundStatus = $creditResponse['refundStatus'] ?? self::REFUND_STATUS_REFUNDED;
        $transaction->update([
            'refund_amount' => $refundAmount,
            'refund_status' => $refundStatus,
            'refund_id' => $refundId,
        ]);

        $response = [
            'SyunoRecvNum' => $transaction->syuno_recv_num,
            'refundStatus' => $refundStatus,
            'refundAmount' => $refundAmount,
            'originalAmount' => $transaction->amount,
            'refundId' => $refundId,
        ];
        if ($transaction->payment_number) {
            $response['transactionId'] = $transaction->payment_number;
        }

        return response()->json($response);
    }

    /**
     * Wellnet/CAFISエラーをapi.pdfの返金APIエラーコードへ寄せる
     */
    private function mapCreditExceptionToApiError(RuntimeException $e): array
    {
        $message = $e->getMessage();

        if (preg_match('/\\bE29\\b/u', $message) || str_contains($message, '有効期限が過ぎ')) {
            return ['code' => 'E29', 'message' => '期限経過: ' . $message];
        }
        if (str_contains($message, 'PAYMENT_NUMBER_DOES_NOT_EXIST')) {
            return ['code' => 'E20', 'message' => '取引不明: ' . $message];
        }
        if (str_contains($message, 'INVALID_OPERATION_REFUNDED')) {
            return ['code' => 'D01', 'message' => '返金不可: ' . $message];
        }
        if (str_contains($message, 'INVALID_OPERATION_CANCELED')) {
            return ['code' => 'D01', 'message' => '返金不可: ' . $message];
        }
        if (preg_match('/\\bD0[2-8]\\b/u', $message) || str_contains($message, 'D81')) {
            // D02: 売上前 / D03: 差額なし（取消推奨） / D04: 返金後金額不正 / D05: 対象なし
            // D06-08: 二重等 / D81: 差額返金済の為取消不可
            return ['code' => 'E30', 'message' => '処理不可: ' . $message];
        }
        if (str_contains($message, 'HTTP 423')) {
            return ['code' => 'E30', 'message' => '処理不可: ' . $message];
        }
        if (str_contains($message, 'USER_ACTION_IN_PROGRESS')) {
            return ['code' => 'E30', 'message' => '処理不可: ' . $message];
        }

        return ['code' => 'E99', 'message' => '返金処理に失敗しました: ' . $message];
    }
}