<?php
// $Id: date_repeat.test,v 1.6 2008-01-10 17:10:19 karens Exp $
/**
 * Test PHP 4 Timezone Conversion
 */
class DateRepeat extends DrupalTestCase {
  function get_info() {
    if (module_exists('date_repeat')) {
      return array('name' => t('Date repeat calculations'), 'desc' => t('Test Date Repeat processes to create arrays of dates from iCal rules.') , 'group' => 'Date tests');
    }
  }

  function testDateRepeat() {
    include_once('./'. drupal_get_path('module', 'date_api') .'/date_api_ical.inc');
    include_once('./'. drupal_get_path('module', 'date_repeat') .'/date_repeat_calc.inc');
    // Examples adapted from http://www.faqs.org/rfcs/rfc2445.html and
    // http://www.kanzaki.com/docs/ical/rrule.html.

    //  Daily for 10 occurrences:
    $start = "1997-09-02 09:00:00";
    $end = "1997-09-30 09:00:00";
    $rule = "RRULE:FREQ=DAILY;COUNT=10";
    $dates = date_repeat_calc($rule, $start, $end, array());
    //  should be (1997 9:00 AM EDT)September 2-11
    $shouldbe = '1997-09-02 09:00:00, 1997-09-03 09:00:00, 1997-09-04 09:00:00, 1997-09-05 09:00:00, 1997-09-06 09:00:00, 1997-09-07 09:00:00, 1997-09-08 09:00:00, 1997-09-09 09:00:00, 1997-09-10 09:00:00, 1997-09-11 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Daily until September 24, 1997:
    $start = "1997-09-02 09:00:00";
    $end = "1997-09-30 09:00:00";
    $rule = "RRULE:FREQ=DAILY;UNTIL=19970924T000000Z";
    $dates = date_repeat_calc($rule, $start, $end, array());
    //  should be (1997 9:00 AM EDT)September 2-23
    $shouldbe = '1997-09-02 09:00:00, 1997-09-03 09:00:00, 1997-09-04 09:00:00, 1997-09-05 09:00:00, 1997-09-06 09:00:00, 1997-09-07 09:00:00, 1997-09-08 09:00:00, 1997-09-09 09:00:00, 1997-09-10 09:00:00, 1997-09-11 09:00:00, 1997-09-12 09:00:00, 1997-09-13 09:00:00, 1997-09-14 09:00:00, 1997-09-15 09:00:00, 1997-09-16 09:00:00, 1997-09-17 09:00:00, 1997-09-18 09:00:00, 1997-09-19 09:00:00, 1997-09-20 09:00:00, 1997-09-21 09:00:00, 1997-09-22 09:00:00, 1997-09-23 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Every other day - until September 30:
    $start = "1997-09-02 09:00:00";
    $end = "1997-09-30 09:00:00";
    $rule = "RRULE:FREQ=DAILY;INTERVAL=2";
    $dates = date_repeat_calc($rule, $start, $end, array());
    // should be (1997 9:00 AM EDT)September2,4,6,8...24,26,28,30;
    $shouldbe = '1997-09-02 09:00:00, 1997-09-04 09:00:00, 1997-09-06 09:00:00, 1997-09-08 09:00:00, 1997-09-10 09:00:00, 1997-09-12 09:00:00, 1997-09-14 09:00:00, 1997-09-16 09:00:00, 1997-09-18 09:00:00, 1997-09-20 09:00:00, 1997-09-22 09:00:00, 1997-09-24 09:00:00, 1997-09-26 09:00:00, 1997-09-28 09:00:00, 1997-09-30 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Every 10 days, 2 occurrences:
    $start = "1997-09-02 09:00:00";
    $end = "1997-09-30 09:00:00";
    $rule = "RRULE:FREQ=DAILY;INTERVAL=10;COUNT=2";
    $dates = date_repeat_calc($rule, $start, $end, array());
    //  should be (1997 9:00 AM EDT)September 2,12
    $shouldbe = '1997-09-02 09:00:00, 1997-09-12 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Weekly for 3 occurrences
    $start = "1997-09-02 09:00:00";
    $end = "1997-09-30 09:00:00";
    $rule = "RRULE:FREQ=WEEKLY;COUNT=3";
    $dates = date_repeat_calc($rule, $start, $end, array());
    //  should be (1997 9:00 AM EDT)September 2,9,16
    $shouldbe = '1997-09-02 09:00:00, 1997-09-09 09:00:00, 1997-09-16 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Weekly until September 24, 1997
    $start = "1997-09-02 09:00:00";
    $end = "1997-09-30 09:00:00";
    $rule = "RRULE:FREQ=WEEKLY;UNTIL=19970924T000000Z";
    //  ==> (1997 9:00 AM EDT)September 2,9,16,23
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-02 09:00:00, 1997-09-09 09:00:00, 1997-09-16 09:00:00, 1997-09-23 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Every other week - forever:
    $start = "1997-09-02 09:00:00";
    $end = "1997-09-30 09:00:00";
    $rule = "RRULE:FREQ=WEEKLY;INTERVAL=2;WKST=SU";
    //  should be (1997 9:00 AM EDT)September 2,16,30
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-02 09:00:00, 1997-09-16 09:00:00, 1997-09-30 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Weekly on Tuesday and Thursday for 4 weeks:
    $start = "1997-09-02 09:00:00";
    $end = "1997-09-30 09:00:00";
    $rule = "RRULE:FREQ=WEEKLY;COUNT=8;WKST=SU;BYDAY=TU,TH";
    // should be(1997 9:00 AM EDT)September 2,4,9,11,16,18,23,25
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-02 09:00:00, 1997-09-04 09:00:00, 1997-09-09 09:00:00, 1997-09-11 09:00:00, 1997-09-16 09:00:00, 1997-09-18 09:00:00, 1997-09-23 09:00:00, 1997-09-25 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Every other week on Tuesday and Thursday, for 5 occurrences:
    $start = "1997-09-02 09:00:00";
    $end = "1997-09-30 09:00:00";
    $rule = "RRULE:FREQ=WEEKLY;INTERVAL=2;COUNT=5;WKST=SU;BYDAY=TU,TH";
    //  should be  (1997 9:00 AM EDT)September 2,4,16,18,30
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-02 09:00:00, 1997-09-04 09:00:00, 1997-09-16 09:00:00, 1997-09-18 09:00:00, 1997-09-30 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Every other week on Monday, Wednesday and Friday until September 24, 1997,
    $start = "1997-09-02 09:00:00";
    $end = "1997-09-30 09:00:00";
    $rule = "RRULE:FREQ=WEEKLY;INTERVAL=2;UNTIL=19970924T000000Z;WKST=SU;BYDAY=MO,WE,FR";
    // should be (1997 9:00 AM EDT)September 2,3,5,15,17,19
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-02 09:00:00, 1997-09-03 09:00:00, 1997-09-05 09:00:00, 1997-09-15 09:00:00, 1997-09-17 09:00:00, 1997-09-19 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Monthly on the 1st Friday for 2 occurrences:
    $start = "1997-09-05 09:00:00";
    $end = "1997-10-31 09:00:00";
    $rule = "RRULE:FREQ=MONTHLY;COUNT=2;BYDAY=1FR";
    //  should be (1997 9:00 AM EDT)September 5;October 3
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-05 09:00:00, 1997-10-03 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Monthly on the 1st Friday until December 24, 1997:
    $start = "1997-09-05 09:00:00";
    $end = "1998-10-01 09:00:00";
    $rule = "RRULE:FREQ=MONTHLY;UNTIL=19971224T000000Z;BYDAY=1FR";
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-05 09:00:00, 1997-10-03 09:00:00, 1997-11-07 09:00:00, 1997-12-05 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Every other month on the 1st and last Sunday of the month for 10 occurrences:
    $start = "1997-09-07 09:00:00";
    $end = "1998-10-01 09:00:00";
    $rule = "RRULE:FREQ=MONTHLY;INTERVAL=2;COUNT=10;BYDAY=1SU,-1SU";
    //  ==> (1997 9:00 AM EDT)September 7,28
    //      (1997 9:00 AM EST)November 2,30
    //      (1998 9:00 AM EST)January 4,25;March 1,29
    //      (1998 9:00 AM EDT)May 3,31
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-07 09:00:00, 1997-09-28 09:00:00, 1997-11-02 09:00:00, 1997-11-30 09:00:00, 1998-01-04 09:00:00, 1998-01-25 09:00:00, 1998-03-01 09:00:00, 1998-03-29 09:00:00, 1998-05-03 09:00:00, 1998-05-31 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Monthly on the second to last Monday of the month for 6 months:
    $start = "1997-09-22 09:00:00";
    $end = "1998-10-01 09:00:00";
    $rule = "RRULE:FREQ=MONTHLY;COUNT=6;BYDAY=-2MO";
    //==> (1997 9:00 AM EDT)September 22;October 20
    //  (1997 9:00 AM EST)November 17;December 22
    //  (1998 9:00 AM EST)January 19;February 16
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-22 09:00:00, 1997-10-20 09:00:00, 1997-11-17 09:00:00, 1997-12-22 09:00:00, 1998-01-19 09:00:00, 1998-02-16 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);


//Every Tuesday, every other month:
    $start = "1997-09-02 09:00:00";
    $end = "1998-02-01 09:00:00";
    $rule = "RRULE:FREQ=MONTHLY;INTERVAL=2;BYDAY=TU";
//  ==> (1997 9:00 AM EDT)September 2,9,16,23,30
//      (1997 9:00 AM EST)November 4,11,18,25
//      (1998 9:00 AM EST)January 6,13,20,27;March 3,10,17,24,31
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-02 09:00:00, 1997-09-09 09:00:00, 1997-09-16 09:00:00, 1997-09-23 09:00:00, 1997-09-30 09:00:00, 1997-11-04 09:00:00, 1997-11-11 09:00:00, 1997-11-18 09:00:00, 1997-11-25 09:00:00, 1998-01-06 09:00:00, 1998-01-13 09:00:00, 1998-01-20 09:00:00, 1998-01-27 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Yearly in June and July for 10 occurrences:
    $start = "1997-06-10 09:00:00";
    $end = "2002-01-01 09:00:00";
    $rule = "RRULE:FREQ=YEARLY;COUNT=10;BYMONTH=6,7";
    //  ==> (1997 9:00 AM EDT)June 10;July 10
    //      (1998 9:00 AM EDT)June 10;July 10
    //      (1999 9:00 AM EDT)June 10;July 10
    //      (2000 9:00 AM EDT)June 10;July 10
    //      (2001 9:00 AM EDT)June 10;July 10
    //  Note: Since none of the BYDAY, BYMONTHDAY or BYYEARDAY components
    //  are specified, the day is gotten from DTSTART
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-06-10 09:00:00, 1997-07-10 09:00:00, 1998-06-10 09:00:00, 1998-07-10 09:00:00, 1999-06-10 09:00:00, 1999-07-10 09:00:00, 2000-06-10 09:00:00, 2000-07-10 09:00:00, 2001-06-10 09:00:00, 2001-07-10 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Every other year on January, February, and March for 10 occurrences:
    $start = "1997-03-10 09:00:00";
    $end = "2004-01-01 09:00:00";
    $rule = "RRULE:FREQ=YEARLY;INTERVAL=2;COUNT=10;BYMONTH=1,2,3";
    //  ==> (1997 9:00 AM EST)March 10
    //      (1999 9:00 AM EST)January 10;February 10;March 10
    //      (2001 9:00 AM EST)January 10;February 10;March 10
    //      (2003 9:00 AM EST)January 10;February 10;March 10
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-03-10 09:00:00, 1999-01-10 09:00:00, 1999-02-10 09:00:00, 1999-03-10 09:00:00, 2001-01-10 09:00:00, 2001-02-10 09:00:00, 2001-03-10 09:00:00, 2003-01-10 09:00:00, 2003-02-10 09:00:00, 2003-03-10 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //An example where the days generated makes a difference because of WKST:
    $start = "1997-08-05 09:00:00";
    $end = "2004-01-01 09:00:00";
    $rule = "RRULE:FREQ=WEEKLY;INTERVAL=2;COUNT=4;BYDAY=TU,SU;WKST=MO";
    //  ==> (1997 EDT)Aug 5,10,19,24
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-08-05 09:00:00, 1997-08-10 09:00:00, 1997-08-19 09:00:00, 1997-08-24 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //changing only WKST from MO to SU, yields different results...
    $start = "1997-08-05 09:00:00";
    $end = "2004-01-01 09:00:00";
    $rule = "RRULE:FREQ=WEEKLY;INTERVAL=2;COUNT=4;BYDAY=TU,SU;WKST=SU";
    // Result: 1997 EDT August 5,17,19,31;
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-08-05 09:00:00, 1997-08-17 09:00:00, 1997-08-19 09:00:00, 1997-08-31 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Every 18 months on the 10th thru 15th of the month for 10 occurrences:
    $start = "1997-09-10 09:00:00";
    $end = "2004-01-01 09:00:00";
    $rule = "RRULE:FREQ=MONTHLY;INTERVAL=18;COUNT=10;BYMONTHDAY=10,11,12,13,14,15";
    //  ==> (1997 9:00 AM EDT)September 10,11,12,13,14,15
    //      (1999 9:00 AM EST)March 10,11,12,13
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-10 09:00:00, 1997-09-11 09:00:00, 1997-09-12 09:00:00, 1997-09-13 09:00:00, 1997-09-14 09:00:00, 1997-09-15 09:00:00, 1999-03-10 09:00:00, 1999-03-11 09:00:00, 1999-03-12 09:00:00, 1999-03-13 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    //Monthly on the third to the last day of the month, forever:
    $start = "1997-09-28 09:00:00";
    $end = "1998-03-01 09:00:00";
    $rule = "RRULE:FREQ=MONTHLY;BYMONTHDAY=-3";
    //  ==> (1997 9:00 AM EDT)September 28
    //      (1997 9:00 AM EST)October 29;November 28;December 29
    //      (1998 9:00 AM EST)January 29;February 26
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-09-28 09:00:00, 1997-10-29 09:00:00, 1997-11-28 09:00:00, 1997-12-29 09:00:00, 1998-01-29 09:00:00, 1998-02-26 09:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

    return;

//Every Thursday in March, forever:
$date = "DTSTART;TZID=US-Eastern:19970313T090000";
$rule = "RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=TH";
//  ==> (1997 9:00 AM EST)March 13,20,27
//      (1998 9:00 AM EST)March 5,12,19,26
//      (1999 9:00 AM EST)March 4,11,18,25

//Every Thursday, but only during June, July, and August, forever:
$date = "DTSTART;TZID=US-Eastern:19970605T090000";
$rule = "RRULE:FREQ=YEARLY;BYDAY=TH;BYMONTH=6,7,8";
//  ==> (1997 9:00 AM EDT)June 5,12,19,26;July 3,10,17,24,31;August 7,14,21,28
//      (1998 9:00 AM EDT)June 4,11,18,25;July 2,9,16,23,30;August 6,13,20,27
//      (1999 9:00 AM EDT)June 3,10,17,24;July 1,8,15,22,29;August 5,12,19,26

//Monthly on the 2nd and 15th of the month for 10 occurrences:
$date = "DTSTART;TZID=US-Eastern:19970902T090000";
$rule = "RRULE:FREQ=MONTHLY;COUNT=10;BYMONTHDAY=2,15";
//  ==> (1997 9:00 AM EDT)September 2,15;October 2,15
//      (1997 9:00 AM EST)November 2,15;December 2,15
//      (1998 9:00 AM EST)January 2,15

//Monthly on the first and last day of the month for 10 occurrences:
$date = "DTSTART;TZID=US-Eastern:19970930T090000";
$rule = "RRULE:FREQ=MONTHLY;COUNT=10;BYMONTHDAY=1,-1";
//  ==> (1997 9:00 AM EDT)September 30;October 1
//      (1997 9:00 AM EST)October 31;November 1,30;December 1,31
//      (1998 9:00 AM EST)January 1,31;February 1

//Every Friday the 13th, forever:
$date = "DTSTART;TZID=US-Eastern:19970902T090000";
$rule = "EXDATE;TZID=US-Eastern:19970902T090000";
$rule = "RRULE:FREQ=MONTHLY;BYDAY=FR;BYMONTHDAY=13";
//  ==> (1998 9:00 AM EST)February 13;March 13;November 13
//      (1999 9:00 AM EDT)August 13
//      (2000 9:00 AM EDT)October 13

//The first Saturday that follows the first Sunday of the month, forever:
$date = "DTSTART;TZID=US-Eastern:19970913T090000";
$rule = "RRULE:FREQ=MONTHLY;BYDAY=SA;BYMONTHDAY=7,8,9,10,11,12,13";
//  ==> (1997 9:00 AM EDT)September 13;October 11
//      (1997 9:00 AM EST)November 8;December 13
//      (1998 9:00 AM EST)January 10;February 7;March 7
//      (1998 9:00 AM EDT)April 11;May 9;June 13...

//Every four years, the first Tuesday after a Monday in November,
//forever (U.S. Presidential Election day):
$date = "DTSTART;TZID=US-Eastern:19961105T090000";
$rule = "RRULE:FREQ=YEARLY;INTERVAL=4;BYMONTH=11;BYDAY=TU;BYMONTHDAY=2,3,4,5,6,7,8";
//  ==> (1996 9:00 AM EST)November 5
//      (2000 9:00 AM EST)November 7
//      (2004 9:00 AM EST)November 2

// TODO:
// BYYEARDAY, BYSETPOS,
// BYHOUR, BYMINUTE, HOURLY, MINUTELY, SECONDLY
// have not yet been implemented in date_repeat.

    //Every 20th Monday of the year, forever:
    $start = "1997-05-19 09:00:00";
    $end = "2002-01-01 09:00:00";
    $rule = "RRULE:FREQ=YEARLY;BYDAY=20MO";
    //  ==> (1997 9:00 AM EDT)May 19
    //      (1998 9:00 AM EDT)May 18
    //      (1999 9:00 AM EDT)May 17
    $dates = date_repeat_calc($rule, $start, $end, array());
    $shouldbe = '1997-03-10 09:00:00, 1999-01-10 00:00:00, 1999-02-10 00:00:00, 1999-03-10 00:00:00, 2001-01-10 00:00:00, 2001-02-10 00:00:00, 2001-03-10 00:00:00, 2003-01-10 00:00:00, 2003-02-10 00:00:00, 2003-03-10 00:00:00';
    $result = implode(', ', $dates);
    $this->assertEqual($result, $shouldbe, $rule .'; Starting '.$start .';  results: '. $result);

//Every 3rd year on the 1st, 100th and 200th day for 10 occurrences:
$date = "DTSTART;TZID=US-Eastern:19970101T090000";
$rule = "RRULE:FREQ=YEARLY;INTERVAL=3;COUNT=10;BYYEARDAY=1,100,200";
//  ==> (1997 9:00 AM EST)January 1
//      (1997 9:00 AM EDT)April 10;July 19
//      (2000 9:00 AM EST)January 1
//      (2000 9:00 AM EDT)April 9;July 18
//      (2003 9:00 AM EST)January 1
//      (2003 9:00 AM EDT)April 10;July 19
//      (2006 9:00 AM EST)January 1

//Monday of week number 20 (where the default start of the week is Monday), forever:
$date = "DTSTART;TZID=US-Eastern:19970512T090000";
$rule = "RRULE:FREQ=YEARLY;BYWEEKNO=20;BYDAY=MO";
//  ==> (1997 9:00 AM EDT)May 12
//      (1998 9:00 AM EDT)May 11
//      (1999 9:00 AM EDT)May 17

//The 3rd instance into the month of one of Tuesday, Wednesday or
//Thursday, for the next 3 months:
$date = "DTSTART;TZID=US-Eastern:19970904T090000";
$rule = "RRULE:FREQ=MONTHLY;COUNT=3;BYDAY=TU,WE,TH;BYSETPOS=3";
//  ==> (1997 9:00 AM EDT)September 4;October 7
//      (1997 9:00 AM EST)November 6

//The 2nd to last weekday of the month:
$date = "DTSTART;TZID=US-Eastern:19970929T090000";
$rule = "RRULE:FREQ=MONTHLY;BYDAY=MO,TU,WE,TH,FR;BYSETPOS=-2";
//  ==> (1997 9:00 AM EDT)September 29
//      (1997 9:00 AM EST)October 30;November 27;December 30
//      (1998 9:00 AM EST)January 29;February 26;March 30

//Every 3 hours from 9:00 AM to 5:00 PM on a specific day:
$date = "DTSTART;TZID=US-Eastern:19970902T090000";
$rule = "RRULE:FREQ=HOURLY;INTERVAL=3;UNTIL=19970902T170000Z";
//  ==> (September 2, 1997 EDT)09:00,12:00,15:00

//Every 15 minutes for 6 occurrences:
$date = "DTSTART;TZID=US-Eastern:19970902T090000";
$rule = "RRULE:FREQ=MINUTELY;INTERVAL=15;COUNT=6";
//  ==> (September 2, 1997 EDT)09:00,09:15,09:30,09:45,10:00,10:15

//Every hour and a half for 4 occurrences:
$date = "DTSTART;TZID=US-Eastern:19970902T090000";
$rule = "RRULE:FREQ=MINUTELY;INTERVAL=90;COUNT=4";
//  ==> (September 2, 1997 EDT)09:00,10:30;12:00;13:30

//Every 20 minutes from 9:00 AM to 4:40 PM every day:
$date = "DTSTART;TZID=US-Eastern:19970902T090000";
$rule = "RRULE:FREQ=DAILY;BYHOUR=9,10,11,12,13,14,15,16;BYMINUTE=0,20,40";
//  or
$rule = "RRULE:FREQ=MINUTELY;INTERVAL=20;BYHOUR=9,10,11,12,13,14,15,16";
//  ==> (September 2, 1997 EDT)9:00,9:20,9:40,10:00,10:20,16:00,16:20,16:40
//      (September 3, 1997 EDT)9:00,9:20,9:40,10:00,10:20,16:00,16:20,16:40


  }
}