moved browse class into its rightful place

1 files changed, 1082 insertions, 0 deletions

diff --git a/modules/horde/Browser.php b/modules/horde/Browser.php
new file mode 100644
index 00000000..cf97dc41
--- /dev/null
+++ b/modules/horde/Browser.php
@@ -0,0 +1,1082 @@
+<?php
+/**
+ * The Browser:: class provides capability information for the current
+ * web client. Browser identification is performed by examining the
+ * HTTP_USER_AGENT environmental variable provide by the web server.
+ *
+ * $Horde: framework/Browser/Browser.php,v 1.167 2005/03/02 16:05:15 jan Exp $
+ *
+ * Copyright 1999-2005 Chuck Hagenbuch <chuck@horde.org>
+ * Copyright 1999-2005 Jon Parise <jon@horde.org>
+ *
+ * See the enclosed file COPYING for license information (LGPL). If you
+ * did not receive this file, see http://www.fsf.org/copyleft/lgpl.html.
+ *
+ * @author  Chuck Hagenbuch <chuck@horde.org>
+ * @author  Jon Parise <jon@horde.org>
+ * @since   Horde 1.3
+ * @package Horde_Browser
+ */
+class Browser {
+
+    /**
+     * Major version number.
+     *
+     * @var integer $_majorVersion
+     */
+    var $_majorVersion = 0;
+
+    /**
+     * Minor version number.
+     *
+     * @var integer $_minorVersion
+     */
+    var $_minorVersion = 0;
+
+    /**
+     * Browser name.
+     *
+     * @var string $_browser
+     */
+    var $_browser = '';
+
+    /**
+     * Full user agent string.
+     *
+     * @var string $_agent
+     */
+    var $_agent = '';
+
+    /**
+     * Lower-case user agent string.
+     *
+     * @var string $_agent
+     */
+    var $_lowerAgent = '';
+
+    /**
+     * HTTP_ACCEPT string
+     *
+     * @var string $_accept
+     */
+    var $_accept = '';
+
+    /**
+     * Platform the browser is running on.
+     *
+     * @var string $_platform
+     */
+    var $_platform = '';
+
+    /**
+     * Known robots.
+     *
+     * @var array $_robots
+     */
+    var $_robots = array(
+        /* The most common ones. */
+        'Googlebot',
+        'msnbot',
+        'Slurp',
+        'Yahoo',
+        /* The rest alphabetically. */
+        'Arachnoidea',
+        'ArchitextSpider',
+        'Ask Jeeves',
+        'B-l-i-t-z-Bot',
+        'ConveraCrawler',
+        'ExtractorPro',
+        'FAST-WebCrawler',
+        'FDSE robot',
+        'fido',
+        'geckobot',
+        'Gigabot',
+        'Girafabot',
+        'grub-client',
+        'Gulliver',
+        'ia_archiver',
+        'InfoSeek',
+        'KIT-Fireball',
+        'LEIA',
+        'Lycos_Spider',
+        'Mediapartners-Google',
+        'MuscatFerret',
+        'NaverBot',
+        'polybot',
+        'Pompos',
+        'Scooter',
+        'Teoma',
+        'TurnitinBot',
+        'Ultraseek',
+        'ViolaBot',
+        'webbandit',
+        'www.almaden.ibm.com/cs/crawler',
+        'ZyBorg',
+    );
+
+    /**
+     * Is this a mobile browser?
+     *
+     * @var boolean $_mobile
+     */
+    var $_mobile = false;
+
+    /**
+     * Features.
+     *
+     * @var array $_features
+     */
+    var $_features = array(
+        'html'       => true,
+        'hdml'       => false,
+        'wml'        => false,
+        'images'     => true,
+        'iframes'    => false,
+        'frames'     => true,
+        'tables'     => true,
+        'java'       => true,
+        'javascript' => true,
+        'dom'        => false,
+        'utf'        => false,
+        'rte'        => false,
+        'homepage'   => false,
+        'accesskey'  => false,
+        'optgroup'   => false,
+        'xmlhttpreq' => false,
+        'cite'       => false,
+    );
+
+    /**
+     * Quirks
+     *
+     * @var array $_quirks
+     */
+    var $_quirks = array(
+        'avoid_popup_windows'        => false,
+        'break_disposition_header'   => false,
+        'break_disposition_filename' => false,
+        'broken_multipart_form'      => false,
+        'buggy_compression'          => false,
+        'cache_same_url'             => false,
+        'cache_ssl_downloads'        => false,
+        'double_linebreak_textarea'  => false,
+        'empty_file_input_value'     => false,
+        'must_cache_forms'           => false,
+        'no_filename_spaces'         => false,
+        'no_hidden_overflow_tables'  => false,
+        'ow_gui_1.3'                 => false,
+        'png_transparency'           => false,
+        'scrollbar_in_way'           => false,
+        'scroll_tds'                 => false,
+    );
+
+    /**
+     * List of viewable image MIME subtypes.
+     * This list of viewable images works for IE and Netscape/Mozilla.
+     *
+     * @var array $_images
+     */
+    var $_images = array('jpeg', 'gif', 'png', 'pjpeg', 'x-png', 'bmp');
+
+    /**
+
+    /**
+     * Returns a reference to the global Browser object, only creating it
+     * if it doesn't already exist.
+     *
+     * This method must be invoked as:
+     *   $browser = &Browser::singleton([$userAgent[, $accept]]);
+     *
+     * @access public
+     *
+     * @param optional string $userAgent  The browser string to parse.
+     * @param optional string $accept     The HTTP_ACCEPT settings to use.
+     *
+     * @return object Browser  The Browser object.
+     */
+    function &singleton($userAgent = null, $accept = null)
+    {
+        static $instances;
+
+        if (!isset($instances)) {
+            $instances = array();
+        }
+
+        $signature = serialize(array($userAgent, $accept));
+        if (empty($instances[$signature])) {
+            $instances[$signature] = new Browser($userAgent, $accept);
+        }
+
+        return $instances[$signature];
+    }
+
+    /**
+     * Create a browser instance (Constructor).
+     *
+     * @access public
+     *
+     * @param optional string $userAgent  The browser string to parse.
+     * @param optional string $accept     The HTTP_ACCEPT settings to use.
+     */
+    function Browser($userAgent = null, $accept = null)
+    {
+        $this->match($userAgent, $accept);
+    }
+
+    /**
+     * Parses the user agent string and inititializes the object with
+     * all the known features and quirks for the given browser.
+     *
+     * @access public
+     *
+     * @param optional string $userAgent  The browser string to parse.
+     * @param optional string $accept     The HTTP_ACCEPT settings to use.
+     */
+    function match($userAgent = null, $accept = null)
+    {
+        // Set our agent string.
+        if (is_null($userAgent)) {
+            if (isset($_SERVER['HTTP_USER_AGENT'])) {
+                $this->_agent = trim($_SERVER['HTTP_USER_AGENT']);
+            }
+        } else {
+            $this->_agent = $userAgent;
+        }
+        $this->_lowerAgent = strtolower($this->_agent);
+
+        // Set our accept string.
+        if (is_null($accept)) {
+            if (isset($_SERVER['HTTP_ACCEPT'])) {
+                $this->_accept = strtolower(trim($_SERVER['HTTP_ACCEPT']));
+            }
+        } else {
+            $this->_accept = strtolower($accept);
+        }
+
+        // Check for UTF support.
+        if (isset($_SERVER['HTTP_ACCEPT_CHARSET'])) {
+            $this->setFeature('utf', strpos(strtolower($_SERVER['HTTP_ACCEPT_CHARSET']), 'utf') !== false);
+        }
+
+        if (!empty($this->_agent)) {
+            $this->_setPlatform();
+
+            if (preg_match('|Opera[/ ]([0-9.]+)|', $this->_agent, $version)) {
+                $this->setBrowser('opera');
+                list($this->_majorVersion, $this->_minorVersion) = explode('.', $version[1]);
+                $this->setFeature('javascript', true);
+                $this->setQuirk('no_filename_spaces');
+
+                switch ($this->_majorVersion) {
+                case 7:
+                    $this->setFeature('dom');
+                    $this->setFeature('iframes');
+                    $this->setFeature('accesskey');
+                    $this->setFeature('optgroup');
+                    $this->setQuirk('double_linebreak_textarea');
+                    break;
+                }
+            } elseif (strpos($this->_lowerAgent, 'elaine/') !== false ||
+                      strpos($this->_lowerAgent, 'palmsource') !== false ||
+                      strpos($this->_lowerAgent, 'digital paths') !== false) {
+                $this->setBrowser('palm');
+                $this->setFeature('images', false);
+                $this->setFeature('frames', false);
+                $this->setFeature('javascript', false);
+                $this->setQuirk('avoid_popup_windows');
+                $this->_mobile = true;
+            } elseif ((preg_match('|MSIE ([0-9.]+)|', $this->_agent, $version)) ||
+                      (preg_match('|Internet Explorer/([0-9.]+)|', $this->_agent, $version))) {
+
+                $this->setBrowser('msie');
+                $this->setQuirk('cache_ssl_downloads');
+                $this->setQuirk('cache_same_url');
+                $this->setQuirk('break_disposition_filename');
+
+                if (strpos($version[1], '.') !== false) {
+                    list($this->_majorVersion, $this->_minorVersion) = explode('.', $version[1]);
+                } else {
+                    $this->_majorVersion = $version[1];
+                    $this->_minorVersion = 0;
+                }
+
+                /* IE on Windows does not support alpha transparency in PNG
+                 * images. */
+                if (preg_match('/windows/i', $this->_agent)) {
+                    $this->setQuirk('png_transparency');
+                }
+
+                /* IE 6 (pre-SP1) and 5.5 (pre-SP1) has buggy compression.
+                 * The versions affected are as follows:
+                 * 6.00.2462.0000  Internet Explorer 6 Public Preview (Beta)
+                 * 6.00.2479.0006  Internet Explorer 6 Public Preview (Beta)
+                                    Refresh
+                 * 6.00.2600.0000  Internet Explorer 6 (Windows XP)
+                 * 5.50.3825.1300   Internet Explorer 5.5 Developer Preview (Beta)
+                 * 5.50.4030.2400   Internet Explorer 5.5 & Internet Tools Beta
+                 * 5.50.4134.0100   Internet Explorer 5.5 for Windows Me (4.90.3000)
+                 * 5.50.4134.0600   Internet Explorer 5.5
+                 * 5.50.4308.2900   Internet Explorer 5.5 Advanced Security Privacy Beta
+                 *
+                 * See:
+                 * ====
+                 * http://support.microsoft.com/kb/164539;
+                 * http://support.microsoft.com/default.aspx?scid=kb;en-us;Q312496)
+                 * http://support.microsoft.com/default.aspx?scid=kb;en-us;Q313712
+                 */
+                $ie_vers = $this->getIEVersion();
+                $buggy_list = array(
+                    '6,00,2462,0000', '6,00,2479,0006', '6,00,2600,0000',
+                    '5,50,3825,1300', '5,50,4030,2400', '5,50,4134,0100',
+                    '5,50,4134,0600', '5,50,4308,2900'
+                );
+                if (!is_null($ie_vers) && in_array($ie_vers, $buggy_list)) {
+                    $this->setQuirk('buggy_compression');
+                }
+
+                /* Some Handhelds have their screen resolution in the
+                 * user agent string, which we can use to look for
+                 * mobile agents. */
+                if (preg_match('/; (120x160|240x280|240x320)\)/', $this->_agent)) {
+                    $this->_mobile = true;
+                }
+
+                switch ($this->_majorVersion) {
+                case 6:
+                    $this->setFeature('javascript', 1.4);
+                    $this->setFeature('dom');
+                    $this->setFeature('iframes');
+                    $this->setFeature('utf');
+                    $this->setFeature('rte');
+                    $this->setFeature('homepage');
+                    $this->setFeature('accesskey');
+                    $this->setFeature('optgroup');
+                    $this->setFeature('xmlhttpreq');
+                    $this->setQuirk('scrollbar_in_way');
+                    $this->setQuirk('broken_multipart_form');
+                    break;
+
+                case 5:
+                    if ($this->getPlatform() == 'mac') {
+                        $this->setFeature('javascript', 1.2);
+                        $this->setFeature('optgroup');
+                    } else {
+                        // MSIE 5 for Windows.
+                        $this->setFeature('javascript', 1.4);
+                        $this->setFeature('dom');
+                        $this->setFeature('xmlhttpreq');
+                        if ($this->_minorVersion >= 5) {
+                            $this->setFeature('rte');
+                        }
+                    }
+                    $this->setFeature('iframes');
+                    $this->setFeature('utf');
+                    $this->setFeature('homepage');
+                    $this->setFeature('accesskey');
+                    if ($this->_minorVersion == 5) {
+                        $this->setQuirk('break_disposition_header');
+                        $this->setQuirk('broken_multipart_form');
+                    }
+                    break;
+
+                case 4:
+                    $this->setFeature('javascript', 1.2);
+                    $this->setFeature('accesskey');
+                    if ($this->_minorVersion > 0) {
+                        $this->setFeature('utf');
+                    }
+                    break;
+
+                case 3:
+                    $this->setFeature('javascript', 1.1);
+                    $this->setQuirk('avoid_popup_windows');
+                    break;
+                }
+            } elseif (preg_match('|ANTFresco/([0-9]+)|', $this->_agent, $version)) {
+                $this->setBrowser('fresco');
+                $this->setFeature('javascript', 1.1);
+                $this->setQuirk('avoid_popup_windows');
+            } elseif (strpos($this->_lowerAgent, 'avantgo') !== false) {
+                $this->setBrowser('avantgo');
+                $this->_mobile = true;
+            } elseif (preg_match('|Konqueror/([0-9]+)|', $this->_agent, $version) ||
+                      preg_match('|Safari/([0-9]+)\.?([0-9]+)?|', $this->_agent, $version)) {
+                // Konqueror and Apple's Safari both use the KHTML
+                // rendering engine.
+                $this->setBrowser('konqueror');
+                $this->setQuirk('empty_file_input_value');
+                $this->setQuirk('no_hidden_overflow_tables');
+                $this->_majorVersion = $version[1];
+                if (isset($version[2])) {
+                    $this->_minorVersion = $version[2];
+                }
+
+                if (strpos($this->_agent, 'Safari') !== false &&
+                    $this->_majorVersion >= 60) {
+                    // Safari.
+                    $this->setFeature('utf');
+                    $this->setFeature('javascript', 1.4);
+                    $this->setFeature('dom');
+                    $this->setFeature('iframes');
+                    if ($this->_majorVersion > 125 ||
+                        ($this->_majorVersion == 125 &&
+                         $this->_minorVersion >= 1)) {
+                        $this->setFeature('utf');
+                        $this->setFeature('accesskey');
+                        $this->setFeature('xmlhttpreq');
+                    }
+                } else {
+                    // Konqueror.
+                    $this->setFeature('javascript', 1.1);
+                    switch ($this->_majorVersion) {
+                    case 3:
+                        $this->setFeature('dom');
+                        $this->setFeature('iframes');
+                        break;
+                    }
+                }
+            } elseif (preg_match('|Mozilla/([0-9.]+)|', $this->_agent, $version)) {
+                $this->setBrowser('mozilla');
+                $this->setQuirk('must_cache_forms');
+
+                list($this->_majorVersion, $this->_minorVersion) = explode('.', $version[1]);
+                switch ($this->_majorVersion) {
+                case 5:
+                    if ($this->getPlatform() == 'win') {
+                        $this->setQuirk('break_disposition_filename');
+                    }
+                    $this->setFeature('javascript', 1.4);
+                    $this->setFeature('dom');
+                    $this->setFeature('accesskey');
+                    $this->setFeature('optgroup');
+                    $this->setFeature('xmlhttpreq');
+                    $this->setFeature('cite');
+                    if (preg_match('|rv:(.*)\)|', $this->_agent, $revision)) {
+                        if ($revision[1] >= 1) {
+                            $this->setFeature('iframes');
+                        }
+                        if ($revision[1] >= 1.3) {
+                            $this->setFeature('rte');
+                        }
+                    }
+                    break;
+
+                case 4:
+                    $this->setFeature('javascript', 1.3);
+                    $this->setQuirk('buggy_compression');
+                    break;
+
+                case 3:
+                default:
+                    $this->setFeature('javascript', 1);
+                    $this->setQuirk('buggy_compression');
+                    break;
+                }
+            } elseif (preg_match('|Lynx/([0-9]+)|', $this->_agent, $version)) {
+                $this->setBrowser('lynx');
+                $this->setFeature('images', false);
+                $this->setFeature('frames', false);
+                $this->setFeature('javascript', false);
+                $this->setQuirk('avoid_popup_windows');
+            } elseif (preg_match('|Links \(([0-9]+)|', $this->_agent, $version)) {
+                $this->setBrowser('links');
+                $this->setFeature('images', false);
+                $this->setFeature('frames', false);
+                $this->setFeature('javascript', false);
+                $this->setQuirk('avoid_popup_windows');
+            } elseif (preg_match('|HotJava/([0-9]+)|', $this->_agent, $version)) {
+                $this->setBrowser('hotjava');
+                $this->setFeature('javascript', false);
+            } elseif (strpos($this->_agent, 'UP/') !== false ||
+                      strpos($this->_agent, 'UP.B') !== false ||
+                      strpos($this->_agent, 'UP.L') !== false) {
+                $this->setBrowser('up');
+                $this->setFeature('html', false);
+                $this->setFeature('javascript', false);
+                $this->setFeature('hdml');
+                $this->setFeature('wml');
+
+                if (strpos($this->_agent, 'GUI') !== false &&
+                    strpos($this->_agent, 'UP.Link') !== false) {
+                    /* The device accepts Openwave GUI extensions for
+                     * WML 1.3. Non-UP.Link gateways sometimes have
+                     * problems, so exclude them. */
+                    $this->setQuirk('ow_gui_1.3');
+                }
+                $this->_mobile = true;
+            } elseif (strpos($this->_agent, 'Xiino/') !== false) {
+                $this->setBrowser('xiino');
+                $this->setFeature('hdml');
+                $this->setFeature('wml');
+                $this->_mobile = true;
+            } elseif (strpos($this->_agent, 'Palmscape/') !== false) {
+                $this->setBrowser('palmscape');
+                $this->setFeature('javascript', false);
+                $this->setFeature('hdml');
+                $this->setFeature('wml');
+                $this->_mobile = true;
+            } elseif (strpos($this->_agent, 'Nokia') !== false) {
+                $this->setBrowser('nokia');
+                $this->setFeature('html', false);
+                $this->setFeature('wml');
+                $this->setFeature('xhtml');
+                $this->_mobile = true;
+            } elseif (strpos($this->_agent, 'Ericsson') !== false) {
+                $this->setBrowser('ericsson');
+                $this->setFeature('html', false);
+                $this->setFeature('wml');
+                $this->_mobile = true;
+            } elseif (strpos($this->_lowerAgent, 'wap') !== false) {
+                $this->setBrowser('wap');
+                $this->setFeature('html', false);
+                $this->setFeature('javascript', false);
+                $this->setFeature('hdml');
+                $this->setFeature('wml');
+                $this->_mobile = true;
+            } elseif (strpos($this->_lowerAgent, 'docomo') !== false ||
+                      strpos($this->_lowerAgent, 'portalmmm') !== false) {
+                $this->setBrowser('imode');
+                $this->setFeature('images', false);
+                $this->_mobile = true;
+            } elseif (strpos($this->_lowerAgent, 'j-') !== false) {
+                $this->setBrowser('mml');
+                $this->_mobile = true;
+            }
+        }
+    }
+
+    /**
+     * Match the platform of the browser.
+     *
+     * This is a pretty simplistic implementation, but it's intended
+     * to let us tell what line breaks to send, so it's good enough
+     * for its purpose.
+     *
+     * @access public
+     *
+     * @since Horde 2.2
+     */
+    function _setPlatform()
+    {
+        if (strpos($this->_lowerAgent, 'wind') !== false) {
+            $this->_platform = 'win';
+        } elseif (strpos($this->_lowerAgent, 'mac') !== false) {
+            $this->_platform = 'mac';
+        } else {
+            $this->_platform = 'unix';
+        }
+    }
+
+    /**
+     * Return the currently matched platform.
+     *
+     * @return string  The user's platform.
+     *
+     * @since Horde 2.2
+     */
+    function getPlatform()
+    {
+        return $this->_platform;
+    }
+
+    /**
+     * Sets the current browser.
+     *
+     * @access public
+     *
+     * @param string $browser  The browser to set as current.
+     */
+    function setBrowser($browser)
+    {
+        $this->_browser = $browser;
+    }
+
+    /**
+     * Determine if the given browser is the same as the current.
+     *
+     * @access public
+     *
+     * @param string $browser  The browser to check.
+     *
+     * @return boolean  Is the given browser the same as the current?
+     */
+    function isBrowser($browser)
+    {
+        return ($this->_browser === $browser);
+    }
+
+    /**
+     * Do we consider the current browser to be a mobile device?
+     *
+     * @return boolean  True if we do, false if we don't.
+     */
+    function isMobile()
+    {
+        return $this->_mobile;
+    }
+
+    /**
+     * Determines if the browser is a robot or not.
+     *
+     * @access public
+     *
+     * @return boolean  True if browser is a known robot.
+     */
+    function isRobot()
+    {
+        foreach ($this->_robots as $robot) {
+            if (strpos($this->_agent, $robot) !== false) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Retrieve the current browser.
+     *
+     * @access public
+     *
+     * @return string  The current browser.
+     */
+    function getBrowser()
+    {
+        return $this->_browser;
+    }
+
+    /**
+     * Retrieve the current browser's major version.
+     *
+     * @access public
+     *
+     * @return integer  The current browser's major version.
+     */
+    function getMajor()
+    {
+        return $this->_majorVersion;
+    }
+
+    /**
+     * Retrieve the current browser's minor version.
+     *
+     * @access public
+     *
+     * @return integer  The current browser's minor version.
+     */
+    function getMinor()
+    {
+        return $this->_minorVersion;
+    }
+
+    /**
+     * Retrieve the current browser's version.
+     *
+     * @access public
+     *
+     * @return string  The current browser's version.
+     */
+    function getVersion()
+    {
+        return $this->_majorVersion . '.' . $this->_minorVersion;
+    }
+
+    /**
+     * Return the full browser agent string.
+     *
+     * @access public
+     *
+     * @return string  The browser agent string.
+     */
+    function getAgentString()
+    {
+        return $this->_agent;
+    }
+
+    /**
+     * Set unique behavior for the current browser.
+     *
+     * @access public
+     *
+     * @param string $quirk           The behavior to set.
+     * @param optional string $value  Special behavior parameter.
+     */
+    function setQuirk($quirk, $value = true)
+    {
+        $this->_quirks[$quirk] = $value;
+    }
+
+    /**
+     * Check unique behavior for the current browser.
+     *
+     * @access public
+     *
+     * @param string $quirk  The behavior to check.
+     *
+     * @return boolean  Does the browser have the behavior set?
+     */
+    function hasQuirk($quirk)
+    {
+        return !empty($this->_quirks[$quirk]);
+    }
+
+    /**
+     * Retreive unique behavior for the current browser.
+     *
+     * @access public
+     *
+     * @param string $quirk  The behavior to retreive.
+     *
+     * @return string  The value for the requested behavior.
+     */
+    function getQuirk($quirk)
+    {
+        return isset($this->_quirks[$quirk])
+               ? $this->_quirks[$quirk]
+               : null;
+    }
+
+    /**
+     * Set capabilities for the current browser.
+     *
+     * @access public
+     *
+     * @param string $feature         The capability to set.
+     * @param optional string $value  Special capability parameter.
+     */
+    function setFeature($feature, $value = true)
+    {
+        $this->_features[$feature] = $value;
+    }
+
+    /**
+     * Check the current browser capabilities.
+     *
+     * @access public
+     *
+     * @param string $feature  The capability to check.
+     *
+     * @return boolean  Does the browser have the capability set?
+     */
+    function hasFeature($feature)
+    {
+        return !empty($this->_features[$feature]);
+    }
+
+    /**
+     * Retreive the current browser capability.
+     *
+     * @access public
+     *
+     * @param string $feature  The capability to retreive.
+     *
+     * @return string  The value of the requested capability.
+     */
+    function getFeature($feature)
+    {
+        return isset($this->_features[$feature])
+               ? $this->_features[$feature]
+               : null;
+    }
+
+    /**
+     * Determine if we are using a secure (SSL) connection.
+     *
+     * @access public
+     *
+     * @return boolean  True if using SSL, false if not.
+     */
+    function usingSSLConnection()
+    {
+        return ((isset($_SERVER['HTTPS']) &&
+                 ($_SERVER['HTTPS'] == 'on')) ||
+                getenv('SSL_PROTOCOL_VERSION'));
+    }
+
+    /**
+     * Returns the server protocol in use on the current server.
+     *
+     * @access public
+     *
+     * @return string  The HTTP server protocol version.
+     */
+    function getHTTPProtocol()
+    {
+        if (isset($_SERVER['SERVER_PROTOCOL'])) {
+            if (($pos = strrpos($_SERVER['SERVER_PROTOCOL'], '/'))) {
+                return substr($_SERVER['SERVER_PROTOCOL'], $pos + 1);
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Determine if files can be uploaded to the system.
+     *
+     * @access public
+     *
+     * @return integer  If uploads allowed, returns the maximum size of the
+     *                  upload in bytes.  Returns 0 if uploads are not
+     *                  allowed.
+     */
+    function allowFileUploads()
+    {
+        if (ini_get('file_uploads')) {
+            if (($dir = ini_get('upload_tmp_dir')) &&
+                !is_writable($dir)) {
+                return 0;
+            }
+            $size = ini_get('upload_max_filesize');
+            switch (strtolower(substr($size, -1, 1))) {
+            case 'k':
+                $size = intval(floatval($size) * 1024);
+                break;
+
+            case 'm':
+                $size = intval(floatval($size) * 1024 * 1024);
+                break;
+
+            default:
+                $size = intval($size);
+                break;
+            }
+            return $size;
+        } else {
+            return 0;
+        }
+    }
+
+    /**
+     * Determines if the file was uploaded or not.  If not, will return the
+     * appropriate error message.
+     *
+     * @access public
+     *
+     * @param string $field           The name of the field containing the
+     *                                uploaded file.
+     * @param optional string $name   The file description string to use in the
+     *                                error message.  Default: 'file'.
+     *
+     * @return mixed  True on success, PEAR_Error on error.
+     */
+    function wasFileUploaded($field, $name = null)
+    {
+        require_once 'PEAR.php';
+
+        if (is_null($name)) {
+            $name = _("file");
+        }
+
+        if (!($uploadSize = Browser::allowFileUploads())) {
+            return PEAR::raiseError(_("File uploads not supported."));
+        }
+
+        /* Get any index on the field name. */
+        require_once 'Horde/Array.php';
+        $index = Horde_Array::getArrayParts($field, $base, $keys);
+
+        if ($index) {
+            /* Index present, fetch the error var to check. */
+            $keys_path = array_merge(array($base, 'error'), $keys);
+            $error = Horde_Array::getElement($_FILES, $keys_path);
+
+            /* Index present, fetch the tmp_name var to check. */
+            $keys_path = array_merge(array($base, 'tmp_name'), $keys);
+            $tmp_name = Horde_Array::getElement($_FILES, $keys_path);
+        } else {
+            /* No index, simple set up of vars to check. */
+            if (!isset($_FILES[$field])) {
+                return PEAR::raiseError(_("No file uploaded"), UPLOAD_ERR_NO_FILE);
+            }
+            $error = $_FILES[$field]['error'];
+            $tmp_name = $_FILES[$field]['tmp_name'];
+        }
+
+        if (!isset($_FILES) || ($error == UPLOAD_ERR_NO_FILE)) {
+            return PEAR::raiseError(sprintf(_("There was a problem with the file upload: No %s was uploaded."), $name), UPLOAD_ERR_NO_FILE);
+        } elseif (($error == UPLOAD_ERR_OK) && is_uploaded_file($tmp_name)) {
+            return true;
+        } elseif (($error == UPLOAD_ERR_INI_SIZE) ||
+                  ($error == UPLOAD_ERR_FORM_SIZE)) {
+            return PEAR::raiseError(sprintf(_("There was a problem with the file upload: The %s was larger than the maximum allowed size (%d bytes)."), $name, $uploadSize), $error);
+        } elseif ($error == UPLOAD_ERR_PARTIAL) {
+            return PEAR::raiseError(sprintf(_("There was a problem with the file upload: The %s was only partially uploaded."), $name), $error);
+        }
+    }
+
+    /**
+     * Returns the headers for a browser download.
+     *
+     * @access public
+     *
+     * @param optional string $filename  The filename of the download.
+     * @param optional string $cType     The content-type description of the
+     *                                   file.
+     * @param optional boolean $inline   True if inline, false if attachment.
+     * @param optional string $cLength   The content-length of this file.
+     *
+     * @since Horde 2.2
+     */
+    function downloadHeaders($filename = 'unknown', $cType = null,
+                             $inline = false, $cLength = null)
+    {
+        /* Remove linebreaks from file names. */
+        $filename = str_replace(array("\r\n", "\r", "\n"), ' ', $filename);
+
+        /* Some browsers don't like spaces in the filename. */
+        if ($this->hasQuirk('no_filename_spaces')) {
+            $filename = strtr($filename, ' ', '_');
+        }
+
+        /* MSIE doesn't like multiple periods in the file name. Convert
+           all periods (except the last one) to underscores. */
+        if ($this->isBrowser('msie')) {
+            if (($pos = strrpos($filename, '.'))) {
+                $filename = strtr(substr($filename, 0, $pos), '.', '_') . substr($filename, $pos);
+            }
+        }
+
+        /* Content-Type/Content-Disposition Header. */
+        if ($inline) {
+            if (!is_null($cType)) {
+                header('Content-Type: ' . trim($cType));
+            } elseif ($this->isBrowser('msie')) {
+                header('Content-Type: application/x-msdownload');
+            } else {
+                header('Content-Type: application/octet-stream');
+            }
+            header('Content-Disposition: inline; filename="' . $filename . '"');
+        } else {
+            if ($this->isBrowser('msie')) {
+                header('Content-Type: application/x-msdownload');
+            } elseif (!is_null($cType)) {
+                header('Content-Type: ' . trim($cType));
+            } else {
+                header('Content-Type: application/octet-stream');
+            }
+
+            if ($this->hasQuirk('break_disposition_header')) {
+                header('Content-Disposition: filename="' . $filename . '"');
+            } else {
+                header('Content-Disposition: attachment; filename="' . $filename . '"');
+            }
+        }
+
+        /* Content-Length Header. Don't send Content-Length for
+         * HTTP/1.1 servers. */
+        if (($this->getHTTPProtocol() != '1.1') && !is_null($cLength)) {
+            header('Content-Length: ' . $cLength);
+        }
+
+        /* Overwrite Pragma: and other caching headers for IE. */
+        if ($this->hasQuirk('cache_ssl_downloads')) {
+            header('Expires: 0');
+            header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
+            header('Pragma: public');
+        }
+    }
+
+    /**
+     * Determines if a browser can display a given MIME type.
+     *
+     * @access public
+     *
+     * @param string $mimetype  The MIME type to check.
+     *
+     * @return boolean  True if the browser can display the MIME type.
+     */
+    function isViewable($mimetype)
+    {
+        $mimetype = strtolower($mimetype);
+        list($type, $subtype) = explode('/', $mimetype);
+
+        if (!empty($this->_accept)) {
+            $wildcard_match = false;
+
+            if (strpos($this->_accept, $mimetype) !== false) {
+                return true;
+            }
+
+            if (strpos($this->_accept, '*/*') !== false) {
+                $wildcard_match = true;
+                if ($type != 'image') {
+                    return true;
+                }
+            }
+
+            /* image/jpeg and image/pjpeg *appear* to be the same
+             * entity, but Mozilla doesn't seem to want to accept the
+             * latter.  For our purposes, we will treat them the
+             * same. */
+            if ($this->isBrowser('mozilla') &&
+                ($mimetype == 'image/pjpeg') &&
+                (strpos($this->_accept, 'image/jpeg') !== false)) {
+                return true;
+            }
+
+            if (!$wildcard_match) {
+                return false;
+            }
+        }
+
+        if (!$this->hasFeature('images') || ($type != 'image')) {
+            return false;
+        }
+
+        return (in_array($subtype, $this->_images));
+    }
+
+    /**
+     * Escape characters in javascript code if the browser requires it.
+     * %23, %26, and %2B (for IE) and %27 need to be escaped or else
+     * jscript will interpret it as a single quote, pound sign, or
+     * ampersand and refuse to work.
+     *
+     * @access public
+     *
+     * @param string $code  The JS code to escape.
+     *
+     * @return string  The escaped code.
+     */
+    function escapeJSCode($code)
+    {
+        $from = $to = array();
+
+        if ($this->isBrowser('msie') ||
+            ($this->isBrowser('mozilla') && ($this->getMajor() >= 5))) {
+            $from = array('%23', '%26', '%2B');
+            $to = array(urlencode('%23'), urlencode('%26'), urlencode('%2B'));
+        }
+        $from[] = '%27';
+        $to[] = '\%27';
+
+        return str_replace($from, $to, $code);
+    }
+
+    /**
+     * Set the IE version in the session.
+     *
+     * @access public
+     *
+     * @param string $ver  The IE Version string.
+     */
+    function setIEVersion($ver)
+    {
+        $_SESSION['__browser'] = array(
+            'ie_version' => $ver
+        );
+    }
+
+    /**
+     * Return the IE version stored in the session, if available.
+     *
+     * @access public
+     *
+     * @return mixed  The IE Version string or null if no string is stored.
+     */
+    function getIEVersion()
+    {
+        return isset($_SESSION['__browser']['ie_version']) ? $_SESSION['__browser']['ie_version'] : null;
+    }
+
+}