<?php
namespace TYPO3\CMS\Core\Http;

/*
 * 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!
 */

use Psr\Http\Message\UploadedFileInterface;
use TYPO3\CMS\Core\Utility\GeneralUtility;

/**
 * Class ServerRequestFactory to create ServerRequest objects
 *
 * Highly inspired by https://github.com/phly/http/
 *
 * @internal Note that this is not public API yet.
 */
class ServerRequestFactory
{
    /**
     * Create a request from the original superglobal variables.
     *
     * @return ServerRequest
     * @throws \InvalidArgumentException when invalid file values given
     * @internal Note that this is not public API yet.
     */
    public static function fromGlobals()
    {
        $serverParameters = $_SERVER;
        $headers = static::prepareHeaders($serverParameters);

        $method = isset($serverParameters['REQUEST_METHOD']) ? $serverParameters['REQUEST_METHOD'] : 'GET';
        $uri = new Uri(GeneralUtility::getIndpEnv('TYPO3_REQUEST_URL'));

        $request = new ServerRequest(
            $uri,
            $method,
            'php://input',
            $headers,
            $serverParameters,
            static::normalizeUploadedFiles($_FILES)
        );

        if (!empty($_COOKIE)) {
            $request = $request->withCookieParams($_COOKIE);
        }
        $queryParameters = GeneralUtility::_GET();
        if (!empty($queryParameters)) {
            $request = $request->withQueryParams($queryParameters);
        }
        $parsedBody = GeneralUtility::_POST();
        if (empty($parsedBody) && in_array($method, ['PUT', 'PATCH', 'DELETE'])) {
            parse_str(file_get_contents('php://input'), $parsedBody);
        }
        if (!empty($parsedBody)) {
            $request = $request->withParsedBody($parsedBody);
        }
        return $request;
    }

    /**
     * Fetch headers from $_SERVER variables
     * which are only the ones starting with HTTP_* and CONTENT_*
     *
     * @param array $server
     * @return array
     */
    protected static function prepareHeaders(array $server)
    {
        $headers = [];
        foreach ($server as $key => $value) {
            if (strpos($key, 'HTTP_COOKIE') === 0) {
                // Cookies are handled using the $_COOKIE superglobal
                continue;
            }
            if (!empty($value)) {
                if (strpos($key, 'HTTP_') === 0) {
                    $name = strtr(substr($key, 5), '_', ' ');
                    $name = strtr(ucwords(strtolower($name)), ' ', '-');
                    $name = strtolower($name);
                    $headers[$name] = $value;
                } elseif (strpos($key, 'CONTENT_') === 0) {
                    $name = substr($key, 8); // Content-
                    $name = 'Content-' . (($name === 'MD5') ? $name : ucfirst(strtolower($name)));
                    $name = strtolower($name);
                    $headers[$name] = $value;
                }
            }
        }
        return $headers;
    }

    /**
     * Normalize uploaded files
     *
     * Transforms each value into an UploadedFileInterface instance, and ensures that nested arrays are normalized.
     *
     * @param array $files
     * @return array
     * @throws \InvalidArgumentException for unrecognized values
     */
    protected static function normalizeUploadedFiles(array $files)
    {
        $normalizedFileUploads = [];
        foreach ($files as $key => $value) {
            if ($value instanceof UploadedFileInterface) {
                $normalizedFileUploads[$key] = $value;
            } elseif (is_array($value)) {
                if (isset($value['tmp_name'])) {
                    $uploadedFiles = self::createUploadedFile($value);
                    if ($uploadedFiles) {
                        $normalizedFileUploads[$key] = $uploadedFiles;
                    }
                } else {
                    $normalizedFileUploads[$key] = self::normalizeUploadedFiles($value);
                }
            } else {
                throw new \InvalidArgumentException('Invalid value in files specification.', 1436717282);
            }
        }
        return $normalizedFileUploads;
    }

    /**
     * Create and return an UploadedFile instance from a $_FILES specification.
     *
     * If the specification represents an array of values, this method will
     * recursively resolve uploaded files.
     *
     * @param array $value $_FILES structure
     * @return UploadedFileInterface[]|UploadedFileInterface|NULL
     */
    protected static function createUploadedFile(array $value)
    {
        if (is_array($value['tmp_name'])) {
            $files = [];
            foreach (array_keys($value['tmp_name']) as $key) {
                $data = [
                    'tmp_name' => $value['tmp_name'][$key],
                    'size'     => $value['size'][$key],
                    'error'    => $value['error'][$key],
                    'name'     => $value['name'][$key],
                    'type'     => $value['type'][$key]
                ];
                $result = self::createUploadedFile($data);
                if ($result) {
                    $files[$key] = $result;
                }
            }
            return $files;
        } elseif (!empty($value['tmp_name'])) {
            return new UploadedFile($value['tmp_name'], $value['size'], $value['error'], $value['name'], $value['type']);
        }
        return null;
    }
}
