source: branches/1.2/workflow/inc/local/functions/function.wf_handle_download.php @ 1349

<?php
/**
 * Handles download requests based on logic provided by the callback function.
 * @param array $request Information about HTTP request
 * @param string $callback Function that provides the logic for the download process.
 * @return void
 * @license http://www.gnu.org/copyleft/gpl.html GPL
 * @package Workflow 
 * @subpackage local 
 * @access public
 */
function wf_handle_download($request, $callback)
{
        /* check if it is in download mode */
        if (!isset($request['download_mode']))
                return;
        else
                if ($request['download_mode'] != "true")
                        return;
        
        /* verify if the callback function exists and is callable */
        if ((function_exists($callback)) && (is_callable($callback)))
        {
                /* prepare the parameters */
                $params = array();
                foreach ($request as $key => $value)
                        $params[$key] = $value;
                
                /* call the callback function and await the result */
                $fileResult = call_user_func($callback, $params);
                
                /* if everything is ok, then proceed with the download of the file */
                if (!is_null($fileResult))
                {
                        if (isset($fileResult['filename']) && isset($fileResult['content']))
                        {
                                        if (ereg('Opera(/| )([0-9].[0-9]{1,2})', $_SERVER['HTTP_USER_AGENT']))
                                        $UserBrowser = "Opera";
                                elseif (ereg('MSIE ([0-9].[0-9]{1,2})', $_SERVER['HTTP_USER_AGENT']))
                                        $UserBrowser = "IE";
                                        else
                                                $UserBrowser = '';
                                
                                $mime_type = ($UserBrowser == 'IE' || $UserBrowser == 'Opera') ? 'application/octetstream' : 'application/octet-stream';
                                header("Pragma: public");
                                header("Cache-Control: cache, must-revalidate");
                                header("Content-Type: application/force-download");
                                header("Content-Disposition: attachment; filename=\"" . $fileResult['filename'] . "\"");
                                header('Pragma: no-cache');
                                header("Expires: 0");
                        header("Content-length: " . strlen($fileResult['content']));
                        echo $fileResult['content'];
                                die();
                        }
                }
                else
                        die();
        }
} 
?>