<?php


namespace TorstenHettstedt\TimekeepingApi\Middleware;


use Psr\Http\Message\ResponseInterface as Response;
use Psr\Http\Message\ServerRequestInterface as Request;
use Psr\Http\Server\MiddlewareInterface;
use Psr\Http\Server\RequestHandlerInterface as RequestHandler;
use Slim\Routing\RouteContext;

class OriginAccessControlHandler implements MiddlewareInterface
{

    /**
     * Process an incoming server request.
     *
     * Processes an incoming server request in order to produce a response.
     * If unable to produce the response itself, it may delegate to the provided
     * request handler to do so.
     */
    public function process(Request $request, RequestHandler $handler): Response
    {
        $response = $handler->handle($request);
        return $this->originAccessControl($request, $response);
    }

    public function originAccessControl(Request $request, Response $response): Response
    {
        $routeContext = RouteContext::fromRequest($request);
        $routingResults = $routeContext->getRoutingResults();
        $methods = $routingResults->getAllowedMethods();
        $requestHeaders = $request->getHeaderLine('Access-Control-Request-Headers');

        if ($this->testRoute($request)) {
            //                     Stunden Minuten Sekunden
            $accessControlMaxAge = 24    * 60    * 60;
            $response = $response->withHeader('Access-Control-Allow-Origin', $this->buildOrigin($request));
            $response = $response->withHeader('Access-Control-Allow-Methods', implode(',', $methods));
            $response = $response->withHeader('Access-Control-Allow-Headers', $requestHeaders);
            $response = $response->withHeader('Access-Control-Max-Age', (string)$accessControlMaxAge);
        }
        return $response;
    }

    protected function testRoute(Request $request): bool
    {
        $corsAllowOriginRegex = $_ENV['CORS_ALLOW_ORIGIN_REGEX'] ?? '/https?:\/\/.*:.*/';
        return preg_match($corsAllowOriginRegex, $this->buildOrigin($request));
    }

    protected function buildOrigin(Request $request): string
    {
        return $request->getHeaderLine('Origin');
    }
}