<?php

// a simple service to run webkitpdf and return the PDF...
// note - this will only run on localhost by default...

// needs pear in the 
// test:  http://localhost/webkitpdf.php

// create a simple file:
/*
ini_set('include_path', 
            dirname(__FILE__). ':' . 
            dirname(__FILE__).'/pear:' . 
            ini_get('include_path'));

require_once 'webkitpdf.php';
new WebkitPdf();
*/


class WebkitPdf
{
    
    function WebkitPdf()
    {
        if (empty($_REQUEST['url'])) {
            $this->h404("missing url");
        }
        
        require_once 'System.php';
        
        $timeout= System::which('timeout');
        if (empty($timeout)) {
            $this->h404("missing timeout");
        }
        
        $xvfb = System::which('xvfb-run');
        if (empty($xvfb)) {
            $this->h404("missing xvfb");
        }
        
        $webkitpdf = System::which('webkitpdf');
        if (empty($webkitpdf )) {
            $this->h404("missing webkitpdf (compile it..)");
        }
        // max delay 20 seconds.? bit generous..
        $delay = empty($_REQUEST['delay']) ? 1 : max(20,$_REQUEST['delay']);
        
        //?? allow injections?
        // not yet..
        
        $outpr = tempnam(ini_get('session.save_path'), 'webkitTMP');
        unlink($outpr);
        $out = $outpr .'.pdf';
        
        // can take 2-5 minutes... 
        
        $cmd = "timeout 300s $xvfb --auto-servernum $webkitpdf  " .
                " --url " . escapeshellarg($_REQUEST['url']) . ' ' .
                " --pdf " . $out . ' ';
                
        $res = `$cmd`;
        
        if (!file_exists($out)) {
            $this->h404("Failed to create file $cmd  ==> $res");
        }
        
        header('Content-type: application/octet-stream');
        
        header("Expires: ");
        header("Cache-Control: must-revalidate, post-check=0,pre-check=0");
        header("Pragma: public");     
        header("Last-Modified: " . gmdate("D, d M Y H:i:s",  time()) . " GMT");

        //header('Content-length: '. filesize($out));
        header('Content-Disposition: attachment; filename="' . htmlspecialchars(basename($out)).  '"');
        ini_set('display_errors', 0);
        
        $fh = fopen($out, 'rb');
        fpassthru($fh);
        
        fclose($fh);
    
    
        unlink($out);
        exit;
        
        
    }
    
    function h404($msg)
    {
        header("HTTP/1.0 404 Not Found");
        echo htmlspecialchars($msg);
        exit;
    }
    
}