<?php

/*

 * This file is part of the Symfony package.

 *

 * (c) Fabien Potencier <fabien@symfony.com>

 *

 * For the full copyright and license information, please view the LICENSE

 * file that was distributed with this source code.

 */

namespace Symfony\Component\HttpFoundation;

/**

 * Response represents an HTTP response.

 *

 * @author Fabien Potencier <fabien@symfony.com>

 *

 * @api

 */

class Response

{

    /**

     * @var \Symfony\Component\HttpFoundation\ResponseHeaderBag

     */

    public $headers;

    protected $content;

    protected $version;

    protected $statusCode;

    protected $statusText;

    protected $charset;

    static public $statusTexts = array(

        100 => 'Continue',

        101 => 'Switching Protocols',

        200 => 'OK',

        201 => 'Created',

        202 => 'Accepted',

        203 => 'Non-Authoritative Information',

        204 => 'No Content',

        205 => 'Reset Content',

        206 => 'Partial Content',

        300 => 'Multiple Choices',

        301 => 'Moved Permanently',

        302 => 'Found',

        303 => 'See Other',

        304 => 'Not Modified',

        305 => 'Use Proxy',

        307 => 'Temporary Redirect',

        400 => 'Bad Request',

        401 => 'Unauthorized',

        402 => 'Payment Required',

        403 => 'Forbidden',

        404 => 'Not Found',

        405 => 'Method Not Allowed',

        406 => 'Not Acceptable',

        407 => 'Proxy Authentication Required',

        408 => 'Request Timeout',

        409 => 'Conflict',

        410 => 'Gone',

        411 => 'Length Required',

        412 => 'Precondition Failed',

        413 => 'Request Entity Too Large',

        414 => 'Request-URI Too Long',

        415 => 'Unsupported Media Type',

        416 => 'Requested Range Not Satisfiable',

        417 => 'Expectation Failed',

        418 => 'I\'m a teapot',

        500 => 'Internal Server Error',

        501 => 'Not Implemented',

        502 => 'Bad Gateway',

        503 => 'Service Unavailable',

        504 => 'Gateway Timeout',

        505 => 'HTTP Version Not Supported',

    );

    /**

     * Constructor.

     *

     * @param string  $content The response content

     * @param integer $status  The response status code

     * @param array   $headers An array of response headers

     *

     * @api

     */

    public function __construct($content = '', $status = 200, $headers = array())

    {

        $this->headers = new ResponseHeaderBag($headers);

        $this->setContent($content);

        $this->setStatusCode($status);

        $this->setProtocolVersion('1.0');

        if (!$this->headers->has('Date')) {

            $this->setDate(new \DateTime(null, new \DateTimeZone('UTC')));

        }

    }

    /**

     * Returns the response content as it will be sent (with the headers).

     *

     * @return string The response content

     */

    public function __toString()

    {

        $this->prepare();

        return

            sprintf('HTTP/%s %s %s', $this->version, $this->statusCode, $this->statusText)."\r\n".

            $this->headers."\r\n".

            $this->getContent();

    }

    /**

     * Clones the current Response instance.

     */

    public function __clone()

    {

        $this->headers = clone $this->headers;

    }

    /**

     * Prepares the Response before it is sent to the client.

     *

     * This method tweaks the Response to ensure that it is

     * compliant with RFC 2616.

     */

    public function prepare()

    {

        if ($this->isInformational() || in_array($this->statusCode, array(204, 304))) {

            $this->setContent('');

        }

        // Fix Content-Type

        $charset = $this->charset ?: 'UTF-8';

        if (!$this->headers->has('Content-Type')) {

            $this->headers->set('Content-Type', 'text/html; charset='.$charset);

        } elseif ('text/' === substr($this->headers->get('Content-Type'), 0, 5) && false === strpos($this->headers->get('Content-Type'), 'charset')) {

            // add the charset

            $this->headers->set('Content-Type', $this->headers->get('Content-Type').'; charset='.$charset);

        }

        // Fix Content-Length

        if ($this->headers->has('Transfer-Encoding')) {

            $this->headers->remove('Content-Length');

        }

    }

    /**

     * Sends HTTP headers.

     */

    public function sendHeaders()

    {

        // headers have already been sent by the developer

        if (headers_sent()) {

            return;

        }

        $this->prepare();

        // status

        header(sprintf('HTTP/%s %s %s', $this->version, $this->statusCode, $this->statusText));

        // headers

        foreach ($this->headers->all() as $name => $values) {

            foreach ($values as $value) {

                header($name.': '.$value, false);

            }

        }

        // cookies

        foreach ($this->headers->getCookies() as $cookie) {

            setcookie($cookie->getName(), $cookie->getValue(), $cookie->getExpiresTime(), $cookie->getPath(), $cookie->getDomain(), $cookie->isSecure(), $cookie->isHttpOnly());

        }

    }

    /**

     * Sends content for the current web response.

     */

    public function sendContent()

    {

        echo $this->content;

    }

    /**

     * Sends HTTP headers and content.

     *

     * @api

     */

    public function send()

    {

        $this->sendHeaders();

        $this->sendContent();

        if (function_exists('fastcgi_finish_request')) {

            fastcgi_finish_request();

        }

    }

    /**

     * Sets the response content

     *

     * Valid types are strings, numbers, and objects that implement a __toString() method.

     *

     * @param mixed $content

     *

     * @api

     */

    public function setContent($content)

    {

        if (null !== $content && !is_string($content) && !is_numeric($content) && !is_callable(array($content, '__toString'))) {

            throw new \UnexpectedValueException('The Response content must be a string or object implementing __toString(), "'.gettype($content).'" given.');

        }

        $this->content = (string) $content;

    }

    /**

     * Gets the current response content

     *

     * @return string Content

     *

     * @api

     */

    public function getContent()

    {

        return $this->content;

    }

    /**

     * Sets the HTTP protocol version (1.0 or 1.1).

     *

     * @param string $version The HTTP protocol version

     *

     * @api

     */

    public function setProtocolVersion($version)

    {

        $this->version = $version;

    }

    /**

     * Gets the HTTP protocol version.

     *

     * @return string The HTTP protocol version

     *

     * @api

     */

    public function getProtocolVersion()

    {

        return $this->version;

    }

    /**

     * Sets response status code.

     *

     * @param integer $code HTTP status code

     * @param string  $text HTTP status text

     *

     * @throws \InvalidArgumentException When the HTTP status code is not valid

     *

     * @api

     */

    public function setStatusCode($code, $text = null)

    {

        $this->statusCode = (int) $code;

        if ($this->isInvalid()) {

            throw new \InvalidArgumentException(sprintf('The HTTP status code "%s" is not valid.', $code));

        }

        $this->statusText = false === $text ? '' : (null === $text ? self::$statusTexts[$this->statusCode] : $text);

    }

    /**

     * Retrieves status code for the current web response.

     *

     * @return string Status code

     *

     * @api

     */

    public function getStatusCode()

    {

        return $this->statusCode;

    }

    /**

     * Sets response charset.

     *

     * @param string $charset Character set

     *

     * @api

     */

    public function setCharset($charset)

    {

        $this->charset = $charset;

    }

    /**

     * Retrieves the response charset.

     *

     * @return string Character set

     *

     * @api

     */

    public function getCharset()

    {

        return $this->charset;

    }

    /**

     * Returns true if the response is worth caching under any circumstance.

     *

     * Responses marked "private" with an explicit Cache-Control directive are

     * considered uncacheable.

     *

     * Responses with neither a freshness lifetime (Expires, max-age) nor cache

     * validator (Last-Modified, ETag) are considered uncacheable.

     *

     * @return Boolean true if the response is worth caching, false otherwise

     *

     * @api

     */

    public function isCacheable()

    {

        if (!in_array($this->statusCode, array(200, 203, 300, 301, 302, 404, 410))) {

            return false;

        }

        if ($this->headers->hasCacheControlDirective('no-store') || $this->headers->getCacheControlDirective('private')) {

            return false;

        }

        return $this->isValidateable() || $this->isFresh();

    }

    /**

     * Returns true if the response is "fresh".

     *

     * Fresh responses may be served from cache without any interaction with the

     * origin. A response is considered fresh when it includes a Cache-Control/max-age

     * indicator or Expiration header and the calculated age is less than the freshness lifetime.

     *

     * @return Boolean true if the response is fresh, false otherwise

     *

     * @api

     */

    public function isFresh()

    {

        return $this->getTtl() > 0;

    }

    /**

     * Returns true if the response includes headers that can be used to validate

     * the response with the origin server using a conditional GET request.

     *

     * @return Boolean true if the response is validateable, false otherwise

     *

     * @api

     */

    public function isValidateable()

    {

        return $this->headers->has('Last-Modified') || $this->headers->has('ETag');

    }

    /**

     * Marks the response as "private".

     *

     * It makes the response ineligible for serving other clients.

     *

     * @api

     */

    public function setPrivate()

    {

        $this->headers->removeCacheControlDirective('public');

        $this->headers->addCacheControlDirective('private');

    }

    /**

     * Marks the response as "public".

     *

     * It makes the response eligible for serving other clients.

     *

     * @api

     */

    public function setPublic()

    {

        $this->headers->addCacheControlDirective('public');

        $this->headers->removeCacheControlDirective('private');

    }

    /**

     * Returns true if the response must be revalidated by caches.

     *

     * This method indicates that the response must not be served stale by a

     * cache in any circumstance without first revalidating with the origin.

     * When present, the TTL of the response should not be overridden to be

     * greater than the value provided by the origin.

     *

     * @return Boolean true if the response must be revalidated by a cache, false otherwise

     *

     * @api

     */

    public function mustRevalidate()

    {

        return $this->headers->hasCacheControlDirective('must-revalidate') || $this->headers->has('must-proxy-revalidate');

    }

    /**

     * Returns the Date header as a DateTime instance.

     *

     * @return \DateTime A \DateTime instance

     *

     * @throws \RuntimeException when the header is not parseable

     *

     * @api

     */

    public function getDate()

    {

        return $this->headers->getDate('Date');

    }

    /**

     * Sets the Date header.

     *

     * @param \DateTime $date A \DateTime instance

     *

     * @api

     */

    public function setDate(\DateTime $date)

    {

        $date->setTimezone(new \DateTimeZone('UTC'));

        $this->headers->set('Date', $date->format('D, d M Y H:i:s').' GMT');

    }

    /**

     * Returns the age of the response.

     *

     * @return integer The age of the response in seconds

     */

    public function getAge()

    {

        if ($age = $this->headers->get('Age')) {

            return $age;

        }

        return max(time() - $this->getDate()->format('U'), 0);