<?php

/*
 * This file is part of the TYPO3 CMS project.
 *
 * It is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, either version 2
 * of the License, or any later version.
 *
 * For the full copyright and license information, please read the
 * LICENSE.txt file that was distributed with this source code.
 *
 * The TYPO3 project - inspiring people to share!
 */

namespace TYPO3\CMS\Extbase\Mvc;

use Psr\Container\ContainerInterface;
use Psr\EventDispatcher\EventDispatcherInterface;
use Psr\Http\Message\ResponseInterface;
use TYPO3\CMS\Extbase\Annotation\IgnoreValidation;
use TYPO3\CMS\Extbase\Event\Mvc\AfterRequestDispatchedEvent;
use TYPO3\CMS\Extbase\Http\ForwardResponse;
use TYPO3\CMS\Extbase\Mvc\Controller\ControllerInterface;
use TYPO3\CMS\Extbase\Mvc\Exception\InfiniteLoopException;
use TYPO3\CMS\Extbase\Mvc\Exception\InvalidControllerException;

/**
 * Dispatches requests to the controller which was specified by the request and
 * returns the response the controller generated.
 * @internal only to be used within Extbase, not part of TYPO3 Core API.
 */
class Dispatcher
{
    private ContainerInterface $container;
    protected EventDispatcherInterface $eventDispatcher;

    public function __construct(
        ContainerInterface $container,
        EventDispatcherInterface $eventDispatcher
    ) {
        $this->container = $container;
        $this->eventDispatcher = $eventDispatcher;
    }

    /**
     * Dispatches a request to a controller and initializes the security framework.
     *
     * @param RequestInterface $request The request to dispatch
     * @throws Exception\InfiniteLoopException
     */
    public function dispatch(RequestInterface $request): ResponseInterface
    {
        $dispatchLoopCount = 0;
        $isDispatched = false;
        while (!$isDispatched) {
            if ($dispatchLoopCount++ > 99) {
                throw new InfiniteLoopException(
                    'Could not ultimately dispatch the request after ' . $dispatchLoopCount
                    . ' iterations. Most probably, a @' . IgnoreValidation::class
                    . ' annotation is missing on re-displaying a form with validation errors.',
                    1217839467
                );
            }
            $controller = $this->resolveController($request);
            $response = $controller->processRequest($request);
            if ($response instanceof ForwardResponse) {
                // The controller action returned an extbase internal Forward response:
                // Another action should be dispatched.
                $request = static::buildRequestFromCurrentRequestAndForwardResponse($request, $response);
            } else {
                // The controller action returned a casual or a HTTP redirect response.
                // Dispatching ends here and response is sent to client.
                $isDispatched = true;
            }
        }
        $this->eventDispatcher->dispatch(new AfterRequestDispatchedEvent($request, $response));
        return $response;
    }

    /**
     * Finds and instantiates a controller that matches the current request.
     * If no controller can be found, an instance of NotFoundControllerInterface is returned.
     *
     * @param RequestInterface $request The request to dispatch
     * @return Controller\ControllerInterface
     * @throws Exception\InvalidControllerException
     */
    protected function resolveController(RequestInterface $request)
    {
        $controllerObjectName = $request->getControllerObjectName();
        $controller = $this->container->get($controllerObjectName);
        if (!$controller instanceof ControllerInterface) {
            throw new InvalidControllerException(
                'Invalid controller "' . $request->getControllerObjectName() . '". The controller must implement the TYPO3\\CMS\\Extbase\\Mvc\\Controller\\ControllerInterface.',
                1476109646
            );
        }
        return $controller;
    }

    /**
     * @internal only to be used within Extbase, not part of TYPO3 Core API.
     * @todo: make this a private method again as soon as the tests, that fake the dispatching of requests, are refactored.
     */
    public static function buildRequestFromCurrentRequestAndForwardResponse(RequestInterface $currentRequest, ForwardResponse $forwardResponse): RequestInterface
    {
        $request = $currentRequest->withControllerActionName($forwardResponse->getActionName());
        if ($forwardResponse->getControllerName() !== null) {
            $request = $request->withControllerName($forwardResponse->getControllerName());
        }
        if ($forwardResponse->getExtensionName() !== null) {
            $request = $request->withControllerExtensionName($forwardResponse->getExtensionName());
        }
        if ($forwardResponse->getArguments() !== null) {
            $request = $request->withArguments($forwardResponse->getArguments());
        }
        /** @var ExtbaseRequestParameters $extbaseRequestParameters */
        $extbaseRequestParameters = clone $request->getAttribute('extbase');
        $extbaseRequestParameters->setOriginalRequest($currentRequest);
        $extbaseRequestParameters->setOriginalRequestMappingResults($forwardResponse->getArgumentsValidationResult());
        return $request->withAttribute('extbase', $extbaseRequestParameters);
    }
}
