vonbraunlabs/slimx

<?php

namespace SlimX\Controllers;

use Psr\Http\Message\RequestInterface;
use Psr\Http\Message\ResponseInterface;
use Slim\Http\Response;

class Action
{
    private $allowedMethods = ['GET', 'POST', 'PUT', 'PATCH', 'DELETE'];
    protected $method;
    protected $pattern;
    protected $callable;
    protected $errorCallable;

    /**
     * Organize the action.
     *
     * @param string $method An HTTP method supported by Slim.
     * @param string $pattern URI to route the request.
     * @param mixed $callable Either an anonymous function or an array with keys
     *  matching the HTTP_ACCEPT and values being the anonymous function to be
     *  called.
     * @param ?callable $errorCallable Optionally, a callback function may be given, to be
     *  called when ACCEPT header doesn't match any of the expected.
     */
    public function __construct(string $method, string $pattern, $callable, ?callable $errorCallable = null)
    {
        if (!in_array($method, $this->allowedMethods)) {
            throw new \Exception(
                "Http method $method is not allowed. List of allowed methods: " .
                implode(', ', $this->allowedMethods)
            );
        }
        $this->method = $method;
        $this->pattern = $pattern;
        $this->callable = $callable;
        $this->errorCallable = $errorCallable;
    }

    public function getMethod()
    {
        return $this->method;
    }

    public function getPattern()
    {
        return $this->pattern;
    }

    public function getCallable()
    {
        if (!is_callable($this->callable)) {
            $this->calculateCallable();
        }

        return $this->callable;
    }

    private function calculateCallable()
    {
        $callable = $this->callable;
        $errorCallable = $this->errorCallable;
        $this->callable = function (
            RequestInterface $request,
            Response $response,
            array $args
        ) use (
            $callable,
            $errorCallable
        ) {
            $headers = $request->getHeaders();
            if (isset($headers['HTTP_ACCEPT'])) {
                foreach ($headers['HTTP_ACCEPT'] as $accept) {
                    if (isset($callable[$accept])) {
                        return $callable[$accept]($request, $response, $args);
                    }
                }
            }

            return null !== $errorCallable ?
                $errorCallable($request, $response) :
                $response->withStatus(406)
                    ->write('API version not present or not accepted');
        };
    }
}