<?php

declare(strict_types=1);

namespace Mezzio\ProblemDetails;

use Mezzio\ProblemDetails\ProblemDetailsResponseFactory;
use Negotiation\Negotiator;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Server\MiddlewareInterface;
use Psr\Http\Server\RequestHandlerInterface;

use function sprintf;

/** @final */
class ProblemDetailsNotFoundHandler implements MiddlewareInterface
{
    /**
     * @param ProblemDetailsResponseFactory $responseFactory Factory to create a response to
     *     update and return when returning an 404 response.
     */
    public function __construct(private readonly ProblemDetailsResponseFactory $responseFactory)
    {
    }

    /**
     * Creates and returns a 404 response.
     */
    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
    {
        // If we cannot provide a representation, act as a no-op.
        if (! $this->canActAsErrorHandler($request)) {
            return $handler->handle($request);
        }

        return $this->responseFactory->createResponse(
            $request,
            404,
            sprintf('Cannot %s %s!', $request->getMethod(), (string) $request->getUri())
        );
    }

    /**
     * Can the middleware act as an error handler?
     */
    private function canActAsErrorHandler(ServerRequestInterface $request): bool
    {
        $accept = $request->getHeaderLine('Accept') ?: '*/*';

        return null !== (new Negotiator())
            ->getBest($accept, ProblemDetailsResponseFactory::NEGOTIATION_PRIORITIES);
    }
}