<?php
 
require_once("class_http.php");
require_once("class_xml.php");
 
$exchange_server = "http://exchange.yourwebsite.com"; // no trailing slash
$exchange_username = "";
$exchange_password = "";
 
$h = new http();
 
$h->headers["Content-Type"] = 'text/xml; charset="UTF-8"';
 
$h->headers["Depth"] = "0";
$h->headers["Translate"] = "f";
$h->xmlrequest = '<?xml version="1.0"?>';
$h->xmlrequest .= <<<end
<g:searchrequest xmlns:g="DAV:">
        <g:sql> SELECT "DAV:id" AS uid,
		"DAV:href" AS url,
		"DAV:creationdate" AS created,
		"urn:schemas:httpmail:subject",
		"urn:schemas:httpmail:textdescription",
		"urn:schemas:calendar:location" AS location,
		"http://schemas.microsoft.com/mapi/id/{00062003-0000-0000-C000-000000000046}/0x811c" AS completed,
		"http://schemas.microsoft.com/mapi/id/{00062003-0000-0000-C000-000000000046}/0x00008105" AS duedate,
		"http://schemas.microsoft.com/mapi/id/{00062003-0000-0000-C000-000000000046}/0x00008104" AS start
		FROM Scope('SHALLOW TRAVERSAL OF "/exchange/$exchange_username/Tasks"')
		WHERE "DAV:contentclass" = 'urn:content-classes:task'
		AND CAST("http://schemas.microsoft.com/mapi/id/{00062003-0000-0000-C000-000000000046}/0x811c" AS "boolean") = CAST(false AS "boolean")
		ORDER BY "DAV:creationdate" DESC
         </g:sql>
</g:searchrequest>
END;
 
if (!$h->fetch($exchange_server."/exchange/$exchange_username/Tasks", 0, null, $exchange_username, $exchange_password, "SEARCH")) {
  exit();
}
 
$x = new xml();
if (!$x->fetch($h->body)) {
    exit();
}
 
function format_time($date_string) {
	$date = str_replace("-", "", $date_string);
	$date = str_replace(":", "", $date);
	$date = substr($date, 0, -5);
	return $date;
}
function format_time_z($date_string) {
	$date = str_replace("-", "", $date_string);
	//$date = str_replace(".000Z", "Z", $date);
	$date = str_replace(":", "", $date);
	$date = substr($date, 0, -5);
	return $date."Z";
}
 
header("Content-Type: text/x-vCalendar");
header("Content-Disposition: inline; filename=tasks.ics");
 
echo "BEGIN:VCALENDAR\n";
echo "VERSION:2.0\n";
echo "PRODID:-//Mozilla.org/NONSGML Mozilla Calendar V1.1//EN\n";
echo "METHOD:PUBLISH\n";
echo "BEGIN:VTIMEZONE\n";
echo "TZID:America/New_York\n";
echo "X-LIC-LOCATION:America/New_York\n";
echo "BEGIN:DAYLIGHT\n";
echo "TZOFFSETFROM:-0500\n";
echo "TZOFFSETTO:-0400\n";
echo "TZNAME:EDT\n";
echo "DTSTART:19700308T020000\n";
echo "RRULE:FREQ=YEARLY;INTERVAL=1;BYDAY=2SU;BYMONTH=3\n";
echo "END:DAYLIGHT\n";
echo "BEGIN:STANDARD\n";
echo "TZOFFSETFROM:-0400\n";
echo "TZOFFSETTO:-0500\n";
echo "TZNAME:EST\n";
echo "DTSTART:19701101T020000\n";
echo "RRULE:FREQ=YEARLY;INTERVAL=1;BYDAY=1SU;BYMONTH=11\n";
echo "END:STANDARD\n";
echo "END:VTIMEZONE\n";
 
foreach($x->data->A_MULTISTATUS[0]->A_RESPONSE as $num => $event) {
	$UID = $event->A_PROPSTAT[0]->A_PROP[0]->UID[0]->_text;
	$SUMMARY = $event->A_PROPSTAT[0]->A_PROP[0]->D_SUBJECT[0]->_text;
	$DESCRIPTION = $event->A_PROPSTAT[0]->A_PROP[0]->D_TEXTDESCRIPTION[0]->_text;
	$CREATED = format_time_z($event->A_PROPSTAT[0]->A_PROP[0]->CREATED[0]->_text);
	$STAMP = format_time_z($event->A_PROPSTAT[0]->A_PROP[0]->START[0]->_text);
	$START = format_time($event->A_PROPSTAT[0]->A_PROP[0]->START[0]->_text);
	$DUE = format_time($event->A_PROPSTAT[0]->A_PROP[0]->DUEDATE[0]->_text);
	$COMPLETED = $event->A_PROPSTAT[0]->A_PROP[0]->COMPLETED[0]->_text;
	echo "BEGIN:VTODO\n";
	echo "CREATED:$CREATED\n";
	echo "LAST-MODIFIED:$START\n";
	echo "SUMMARY:$SUMMARY\n";
	echo "DTSTAMP:$START\n";
	echo "UID:$UID\n";
	echo "SUMMARY:$SUMMARY\n";
	echo "DTSTART;TZID=America/New_York:$START\n";
	echo "DUE;TZID=America/New_York:$DUE\n";
#	echo "X-MOZ-GENERATION:2\n";
#	echo "DESCRIPTION:$DESCRIPTION\n";
	echo "END:VTODO\n";
#var_dump($x); break; die();
}
echo "END:VCALENDAR";
 
// You can print out the response to help troubleshoot.
?>