Phred/src/Http/Support/DefaultErrorFormatNegotiator.php

<?php
declare(strict_types=1);

namespace Phred\Http\Support;

use Phred\Http\Contracts\ErrorFormatNegotiatorInterface;
use Psr\Http\Message\ServerRequestInterface as ServerRequest;

final class DefaultErrorFormatNegotiator implements ErrorFormatNegotiatorInterface
{
    public function apiFormat(ServerRequest $request): string
    {
        $accept = $request->getHeaderLine('Accept');
        return str_contains($accept, 'application/vnd.api+json') ? 'jsonapi' : 'rest';
    }

    public function wantsHtml(ServerRequest $request): bool
    {
        $accept = $request->getHeaderLine('Accept');
        // Only return true if text/html is explicitly mentioned and is likely the preferred format
        return str_contains($accept, 'text/html');
    }
}