<?php

declare(strict_types=1);

namespace App\Http\Middleware;

use Closure;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Cache;

/**
 * Idempotency key support for safe POST retries.
 *
 * If Idempotency-Key header is present, caches the response for 24h.
 * Subsequent requests with the same key return the cached response.
 */
class IdempotencyKey
{
    public function handle(Request $request, Closure $next): mixed
    {
        if ($request->method() !== 'POST') {
            return $next($request);
        }

        $key = $request->header('Idempotency-Key');
        if (! $key) {
            return $next($request);
        }

        $cacheKey = 'idempotency:' . hash('sha256', $key);

        // Return cached response if exists
        $cached = Cache::get($cacheKey);
        if ($cached) {
            return response()->json($cached['body'], $cached['status'])
                ->header('X-Idempotency-Replayed', 'true');
        }

        $response = $next($request);

        // Cache successful responses for 24h
        if ($response->status() < 500) {
            Cache::put($cacheKey, [
                'body' => json_decode($response->getContent(), true),
                'status' => $response->status(),
            ], 86400);
        }

        return $response;
    }
}