gjerokrsteski/pimf-framework

<?php
/**
 * Util
 *
 * @copyright Copyright (c)  Gjero Krsteski (http://krsteski.de)
 * @license   http://opensource.org/licenses/MIT MIT License
 */

namespace Pimf\Util;

use Pimf\Config;
use Pimf\Sapi;

/**
 * Manages a raw HTTP header sending.
 *
 * @package Util
 * @author  Gjero Krsteski <gjero@krsteski.de>
 */
class Header extends Header\ContentType
{
    /**
     * @var string
     */
    private static $userAgent;

    /**
     * @var string
     */
    private static $IfModifiedSince;

    /**
     * @var string
     */
    private static $IfNoneMatch;

    /**
     * @param string $userAgent
     * @param string $IfModifiedSince
     * @param string $IfNoneMatch
     */
    public static function edge($userAgent, $IfModifiedSince, $IfNoneMatch)
    {
        self::$userAgent = $userAgent;
        self::$IfModifiedSince = $IfModifiedSince;
        self::$IfNoneMatch = $IfNoneMatch;
    }

    /**
     * Removes previously set headers.
     */
    public static function clear()
    {
        if (headers_sent() && !error_get_last()) {
            foreach ((array)headers_list() as $header) {
                header_remove($header);
            }
        }
    }

    /**
     * @param string  $url
     * @param boolean $exit
     */
    public static function toLocation($url, $exit = true)
    {
        header('Location: ' . $url);
        if ($exit) {
            exit(1);
        }
    }

    /**
     * @param int     $code
     * @param string  $status
     * @param boolean $exit
     */
    protected static function view($code, $status, $exit = true)
    {
        if (Sapi::isCli()) {
            echo $status . PHP_EOL;
            if ($exit) {
                exit;
            }
        }

        self::send($code, $status);

        $appTpl = str_replace('/', DS, BASE_PATH . 'app/' . Config::get('app.name') . '/_error/' . $code . '.php');
        $coreTpl = str_replace('/', DS, BASE_PATH . 'pimf-framework/core/Pimf/_error/' . $code . '.php');
        $coreTpl = str_replace(DS . 'pimf-framework' . DS . 'pimf-framework' . DS, DS . 'pimf-framework' . DS,
            $coreTpl);

        if (file_exists($appTpl) && is_readable($appTpl)) {
            include $appTpl;
            if ($exit) {
                exit(1);
            }
        }

        include $coreTpl;
        if ($exit) {
            exit(1);
        }
    }

    /**
     * @param string  $msg
     * @param boolean $exit
     */
    public static function sendInternalServerError($msg = '', $exit = true)
    {
        self::view(500, $msg, $exit);
    }

    /**
     * @param string  $msg
     * @param boolean $exit
     */
    public static function sendNotFound($msg = '', $exit = true)
    {
        self::view(404, $msg, $exit);
    }

    /**
     * Handles setting pages that are always to be revalidated for freshness by any cache.
     *
     * @param int $last_modified Timestamp in seconds
     */
    public static function exitIfNotModifiedSince($last_modified)
    {
        if (self::isModified($last_modified)) {
            self::sendNotModified();
            exit(0);
        }

        $last_modified = gmdate('D, d M Y H:i:s', $last_modified) . ' GMT';
        header("Cache-Control: must-revalidate");
        header("Last Modified: $last_modified");
    }

    /**
     * Actual HTTP caching validation.
     *
     * @param int    $mtime In seconds
     * @param string $etag
     *
     * @return bool
     */
    public static function isModified($mtime, $etag = '')
    {
        $modifiedSince = strtotime(preg_replace('/;.*$/', '', self::$IfModifiedSince));

        return !($modifiedSince >= $mtime || self::$IfNoneMatch == $etag);
    }

    /**
     * If you want to allow a page to be cached by shared proxies for one minute.
     *
     * @param int $seconds Interval in seconds
     */
    public static function cacheNoValidate($seconds = 60)
    {
        self::cachePage($seconds);
        // HTTP/1.1 support
        header("Cache-Control: public,max-age=$seconds");
    }

    /**
     * If instead you have a page that has personalization on it
     * (say, for example, the splash page contains local news as well),
     * you can set a copy to be cached only by the browser.
     *
     * @param int $seconds Interval in seconds
     */
    public static function cacheBrowser($seconds = 60)
    {
        self::cachePage($seconds);
        // HTTP/1.1 support
        header("Cache-Control: private,max-age=$seconds,s-maxage=0");
    }

    private static function cachePage($seconds)
    {
        $now = time();
        $lmtime = gmdate('D, d M Y H:i:s', $now) . ' GMT';
        $extime = gmdate('D, d M Y H:i:s', $now + $seconds) . ' GMT';
        // backwards compatibility for HTTP/1.0 clients
        header("Last Modified: $lmtime");
        header("Expires: $extime");
    }


    /**
     * If you want to try as hard as possible to keep a page from being cached anywhere.
     */
    public static function cacheNone()
    {
        // backwards compatibility for HTTP/1.0 clients
        header("Expires: 0");
        header("Pragma: no-cache");
        // HTTP/1.1 support
        header("Cache-Control: no-cache,no-store,max-age=0,s-maxage=0,must-revalidate");
    }

    /**
     * Sends file as download-header through any firewall to the browsers like >=IE6 >=FF3.6, Safari, Chrome, Opera.
     *
     * @link http://reeg.junetz.de/DSP/node16.html
     * @link http://www.php.net/manual/de/function.header.php#88038
     *
     * @param string  $fileOrString
     * @param string  $fileName
     * @param boolean $exit Optional for testing
     */
    public static function sendDownloadDialog($fileOrString, $fileName, $exit = true)
    {
        $disposition = (false !== strpos(self::$userAgent, 'MSIE 5.5')) ? '' : 'attachment; ';

        header("Pragma: public");
        header("Expires: 0");
        header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
        header("Cache-Control: private", false);
        header("Content-Disposition: " . $disposition . "filename=" . $fileName . ";");

        if (is_file($fileOrString)) {
            readfile($fileOrString);
        } else {
            echo $fileOrString;
        }

        if ($exit) {
            exit(0);
        }
    }
}