<?php

declare(strict_types=1);

namespace UploadLogger\Detectors;

use UploadLogger\Core\Context;
use UploadLogger\Core\DetectorInterface;

final class MimeDetector implements DetectorInterface
{
    public function getName(): string
    {
        return 'mime_sniff';
    }

    /**
     * @param array<string, mixed> $input
     * @return array<string, mixed>
     */
    public function detect(Context $context, array $input = []): array
    {
        $name = (string)($input['name'] ?? '');
        $realMime = (string)($input['real_mime'] ?? 'unknown');

        $suspicious = false;
        $reasons = [];

        if ($this->isFakeImage($name, $realMime)) {
            $suspicious = true;
            $reasons[] = 'fake_image';
        }

        return [
            'suspicious' => $suspicious,
            'reasons' => $reasons,
        ];
    }

    private function isFakeImage(string $name, string $realMime): bool
    {
        if (preg_match('/\.(png|jpe?g|gif|webp|bmp|ico|svg)$/i', $name)) {
            if (!preg_match('/^image\//', $realMime)) {
                return true;
            }
        }
        return false;
    }
}