<?php

namespace App\Controllers;

use App\Config;
use Psr\Http\Message\ResponseInterface;
use Slim\Psr7\Request;
use Slim\Psr7\Response;
use SplFileInfo;
use Symfony\Contracts\Cache\CacheInterface;
use Symfony\Contracts\Translation\TranslatorInterface;

class FileInfoController
{
    /** @var Config The application configuration */
    protected $config;

    /** @var CacheInterface The application cache */
    protected $cache;

    /** @var TranslatorInterface Translator component */
    protected $translator;

    /** Create a new FileInfoHandler object. */
    public function __construct(
        Config $config,
        CacheInterface $cache,
        TranslatorInterface $translator
    ) {
        $this->config = $config;
        $this->cache = $cache;
        $this->translator = $translator;
    }

    /** Invoke the FileInfoHandler. */
    public function __invoke(Request $request, Response $response): ResponseInterface
    {
        $path = $request->getQueryParams()['info'];

        $file = new SplFileInfo(
            (string) realpath($this->config->get('base_path') . '/' . $path)
        );

        if (! $file->isFile()) {
            return $response->withStatus(404, $this->translator->trans('error.file_not_found'));
        }

        if ($file->getSize() >= (int) $this->config->get('max_hash_size')) {
            return $response->withStatus(500, $this->translator->trans('error.file_size_exceeded'));
        }

        $response->getBody()->write($this->cache->get(
            sprintf('file-info-%s', sha1((string) $file->getRealPath())),
            function () use ($file): string {
                return (string) json_encode(['hashes' => $this->calculateHashes($file)]);
            }
        ));

        return $response->withHeader('Content-Type', 'application/json');
    }

    /** Get an array of hashes for a file. */
    protected function calculateHashes(SplFileInfo $file): array
    {
        return [
            'md5' => hash_file('md5', (string) $file->getRealPath()),
            'sha1' => hash_file('sha1', (string) $file->getRealPath()),
            'sha256' => hash_file('sha256', (string) $file->getRealPath()),
        ];
    }
}