<?php
/************************************************************************
 * This file is part of EspoCRM.
 *
 * EspoCRM - Open Source CRM application.
 * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
 * Website: https://www.espocrm.com
 *
 * EspoCRM is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * EspoCRM is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU General Public License version 3.
 *
 * In accordance with Section 7(b) of the GNU General Public License version 3,
 * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
 ************************************************************************/

namespace Espo\Core\ApplicationRunners;

use Espo\Core\{
    Application\Runner,
    ApplicationUser,
    Authentication\AuthenticationFactory,
    Api\AuthBuilderFactory,
    Api\ErrorOutput,
    Api\RequestWrapper,
    Api\ResponseWrapper,
    Api\RouteProcessor,
    Utils\Route,
    Utils\Log,
};

use Slim\{
    App as SlimApp,
    Factory\AppFactory as SlimAppFactory,
};

use Psr\Http\{
    Message\ResponseInterface as Psr7Response,
    Message\ServerRequestInterface as Psr7Request,
};

use Exception;
use Throwable;

/**
 * Runs API request processing.
 */
class Api implements Runner
{
    private $routeProcessor;

    private $authenticationFactory;

    private $applicationUser;

    private $routeUtil;

    private $authBuilderFactory;

    private $errorOutput;

    private $log;

    public function __construct(
        RouteProcessor $routeProcessor,
        AuthenticationFactory $authenticationFactory,
        ApplicationUser $applicationUser,
        Route $routeUtil,
        AuthBuilderFactory $authBuilderFactory,
        ErrorOutput $errorOutput,
        Log $log
    ) {
        $this->routeProcessor = $routeProcessor;
        $this->authenticationFactory = $authenticationFactory;
        $this->applicationUser = $applicationUser;
        $this->routeUtil = $routeUtil;
        $this->authBuilderFactory = $authBuilderFactory;
        $this->errorOutput = $errorOutput;
        $this->log = $log;
    }

    public function run(): void
    {
        $slim = SlimAppFactory::create();

        $slim->setBasePath(Route::detectBasePath());

        $slim->addRoutingMiddleware();

        $routeList = $this->routeUtil->getFullList();

        foreach ($routeList as $item) {
            $this->addRoute($slim, $item);
        }

        $slim->addErrorMiddleware(false, true, true, $this->log);

        $slim->run();
    }

    private function addRoute(SlimApp $slim, array $item): void
    {
        $method = strtolower($item['method']);
        $route = $item['route'];

        $slim->$method(
            $route,
            function (Psr7Request $request, Psr7Response $response, array $args) use ($item, $slim)
            {
                $routeParams = $this->getRouteParams($item, $args);

                $requestWrapped = new RequestWrapper($request, $slim->getBasePath(), $routeParams);

                $responseWrapped = new ResponseWrapper($response);

                $this->processRequest($item, $requestWrapped, $responseWrapped);

                return $responseWrapped->getResponse();
            }
        );
    }

    private function getRouteParams(array $item, array $args): array
    {
        $params = [];

        $routeParams = $item['params'] ?? [];

        $paramKeys = array_keys($routeParams);

        $setKeyList = [];

        foreach ($paramKeys as $key) {
            $value = $routeParams[$key];

            $paramName = $key;

            if ($value[0] === ':') {
                $realKey = substr($value, 1);

                $params[$paramName] = $args[$realKey];

                $setKeyList[] = $realKey;

                continue;
            }

            $params[$paramName] = $value;
        }

        foreach ($args as $key => $value) {
            if (in_array($key, $setKeyList)) {
                continue;
            }

            $params[$key] = $value;
        }

        return $params;
    }

    private function processRequest(
        array $item,
        RequestWrapper $requestWrapped,
        ResponseWrapper $responseWrapped
    ): void {

        $noAuth = $item['noAuth'] ?? false;
        $route = $item['route'];

        try {
            $authRequired = !$noAuth;

            $authentication = $this->authenticationFactory->create();

            $apiAuth = $this->authBuilderFactory
                ->create()
                ->setAuthentication($authentication)
                ->setAuthRequired($authRequired)
                ->build();

            $authResult = $apiAuth->process($requestWrapped, $responseWrapped);

            if (!$authResult->isResolved()) {
                return;
            }

            if ($authResult->isResolvedUseNoAuth()) {
                $this->applicationUser->setupSystemUser();
            }

            ob_start();

            $this->routeProcessor->process($route, $requestWrapped, $responseWrapped);

            ob_clean();
        }
        catch (Exception $exception) {
            $this->handleException($exception, $requestWrapped, $responseWrapped, $route);
        }
    }

    private function handleException(
        Throwable $exception,
        RequestWrapper $requestWrapped,
        ResponseWrapper $responseWrapped,
        string $route
    ): void {

        try {
            $this->errorOutput->process($requestWrapped, $responseWrapped, $exception, $route);
        }
        catch (Throwable $exception) {
            $this->log->error($exception->getMessage());

            $responseWrapped->setStatus(500);
        }
    }
}