Allow for meeting to be scheduled every 4 weeks.

This allows for by weekly meetings to be run at alternate
times.

Change-Id: Ief437e53719c123399de8874469ef16540d3b3fd
Signed-off-by: Graham Hayes <gr@ham.ie>

meetings/example3.yaml

@@ -0,0 +1,19 @@
+project: Example alternating quadweekly meeting
+agenda_url: http://agenda.com/
+project_url: http://project.com
+schedule:
+  - time: '1700'
+    duration: 45
+    start_date: 20150801
+    day: Thursday
+    irc: openstack-meeting
+    frequency: quadweekly
+  - time: '600'
+    duration: 45
+    start_date: 20150801
+    day: Thursday
+    irc: openstack-meeting
+    frequency: quadweekly-alternate
+chair: John Doe
+description:  >
+  quadweekly

yaml2ical/meeting.py

@@ -136,13 +136,27 @@ class Schedule(object):
 
     def conflicts(self, other):
         """Checks for conflicting schedules."""
-        alternating = set(['biweekly-odd', 'biweekly-even'])
+
+        def _non_weekly_conflict_detection(self, other):
+            week = {
+                'weekly': set([0, 1, 2, 3]),
+                'biweekly-even': set([0, 2]),
+                'biweekly-odd': set([1, 3]),
+                'quadweekly': set([0]),
+                'quadweekly-week-1': set([1]),
+                'quadweekly-week-2': set([2]),
+                'quadweekly-week-3': set([3]),
+                'quadweekly-alternate': set([2]),
+            }
+
+            return len(week[self.freq].intersection(week[other.freq])) > 0
+
         # NOTE(tonyb): .meeting_start also includes the day of the week. So no
         #              need to check .day explictly
         return ((self.irc == other.irc) and
                 ((self.meeting_start < other.meeting_end) and
                  (other.meeting_start < self.meeting_end)) and
-                (set([self.freq, other.freq]) != alternating))
+                _non_weekly_conflict_detection(self, other))
 
 
 class Meeting(object):

yaml2ical/recurrence.py

@@ -78,6 +78,34 @@ class BiWeeklyRecurrence(object):
         return "Every two weeks (on %s weeks)" % self.style
 
 
+class QuadWeeklyRecurrence(object):
+    """Meetings occuring every 4 weeks.
+
+    A week number can be supplied to offset meetings
+    """
+    def __init__(self, week=0):
+        self.week = week
+
+    def next_occurence(self, current_date, day):
+        """Calculate the next biweekly meeting.
+
+        :param current_date: the current date
+        :param day: scheduled day of the meeting
+        :returns: datetime object of next meeting
+        """
+        nextweek_day = WeeklyRecurrence().next_occurence(current_date, day)
+        if nextweek_day.isocalendar()[1] % 4 == self.week:
+            return nextweek_day
+        # If week doesn't match rule, skip one week
+        return self.next_occurence(nextweek_day + datetime.timedelta(7), day)
+
+    def rrule(self):
+        return {'freq': 'weekly', 'interval': 4}
+
+    def __str__(self):
+        return "Every four weeks" % self.style
+
+
 class AdhocRecurrence(object):
     """Meetings occuring as needed.
 
@@ -105,5 +133,10 @@ supported_recurrences = {
     'weekly': WeeklyRecurrence(),
     'biweekly-odd': BiWeeklyRecurrence(style='odd'),
     'biweekly-even': BiWeeklyRecurrence(),
+    'quadweekly': QuadWeeklyRecurrence(week=0),
+    'quadweekly-week-1': QuadWeeklyRecurrence(week=1),
+    'quadweekly-week-2': QuadWeeklyRecurrence(week=2),
+    'quadweekly-week-3': QuadWeeklyRecurrence(week=3),
+    'quadweekly-alternate': QuadWeeklyRecurrence(week=2),
     'adhoc': AdhocRecurrence(),
 }

yaml2ical/tests/sample_data.py

@@ -272,3 +272,93 @@ chair: Shannon Stacker
 description: >
     Adhoc random meeting for Subteam project.
 """
+
+QUADWEEKLY_MEETING_ALTERNATING = """
+project: OpenStack Random Meeting
+agenda_url: http://agenda.com/
+project_url: http://project.com
+schedule:
+  - time: '2200'
+    day: Wednesday
+    irc: openstack-meeting
+    frequency: quadweekly
+  - time: '600'
+    duration: 45
+    start_date: 20150801
+    day: Thursday
+    irc: openstack-meeting
+    frequency: quadweekly-alternate
+chair: John Doe
+description:  >
+  Example alternating quadweekly meeting
+"""
+
+QUADWEEKLY_MEETING = """
+project: OpenStack Random Meeting
+agenda_url: http://agenda.com/
+project_url: http://project.com
+schedule:
+  - time: '2200'
+    day: Wednesday
+    irc: openstack-meeting
+    frequency: quadweekly
+chair: John Doe
+description:  >
+  Example Quadweekly meeting
+"""
+
+QUADWEEKLY_MEETING_WEEK_1 = """
+project: OpenStack Random Meeting
+agenda_url: http://agenda.com/
+project_url: http://project.com
+schedule:
+  - time: '2200'
+    day: Wednesday
+    irc: openstack-meeting
+    frequency: quadweekly-week-1
+chair: John Doe
+description:  >
+  Example Quadweekly meeting on week 1
+"""
+
+QUADWEEKLY_MEETING_WEEK_2 = """
+project: OpenStack Random Meeting
+agenda_url: http://agenda.com/
+project_url: http://project.com
+schedule:
+  - time: '2200'
+    day: Wednesday
+    irc: openstack-meeting
+    frequency: quadweekly-week-2
+chair: John Doe
+description:  >
+  Example Quadweekly meeting on week 2
+"""
+
+QUADWEEKLY_MEETING_WEEK_3 = """
+project: OpenStack Random Meeting
+agenda_url: http://agenda.com/
+project_url: http://project.com
+schedule:
+  - time: '2200'
+    day: Wednesday
+    irc: openstack-meeting
+    frequency: quadweekly-week-3
+chair: John Doe
+description:  >
+  Example Quadweekly meeting on week 3
+"""
+
+QUADWEEKLY_MEETING_ALTERNATE = """
+project: OpenStack Random Meeting
+agenda_url: http://agenda.com/
+project_url: http://project.com
+schedule:
+  - time: '2200'
+    day: Wednesday
+    irc: openstack-meeting
+    frequency: quadweekly-alternate
+chair: John Doe
+description:  >
+  Example Quadweekly Alternate meeting
+"""

yaml2ical/tests/test_meeting.py

@@ -78,6 +78,77 @@ class MeetingTestCase(unittest.TestCase):
             sample_data.MEETING_MONDAY_LATE,
             sample_data.MEETING_TUESDAY_EARLY)
 
+    def test_quadweekly_conflicts(self):
+        self.should_be_conflicting(
+            sample_data.BIWEEKLY_EVEN_MEETING,
+            sample_data.QUADWEEKLY_MEETING_ALTERNATING)
+        self.should_be_conflicting(
+            sample_data.BIWEEKLY_EVEN_MEETING,
+            sample_data.QUADWEEKLY_MEETING)
+        self.should_be_conflicting(
+            sample_data.BIWEEKLY_EVEN_MEETING,
+            sample_data.QUADWEEKLY_MEETING_ALTERNATE)
+        self.should_be_conflicting(
+            sample_data.BIWEEKLY_EVEN_MEETING,
+            sample_data.QUADWEEKLY_MEETING_WEEK_2)
+        self.should_not_conflict(
+            sample_data.BIWEEKLY_EVEN_MEETING,
+            sample_data.QUADWEEKLY_MEETING_WEEK_1)
+        self.should_not_conflict(
+            sample_data.BIWEEKLY_EVEN_MEETING,
+            sample_data.QUADWEEKLY_MEETING_WEEK_3)
+        self.should_be_conflicting(
+            sample_data.BIWEEKLY_EVEN_MEETING,
+            sample_data.QUADWEEKLY_MEETING)
+        self.should_be_conflicting(
+            sample_data.BIWEEKLY_ODD_MEETING,
+            sample_data.QUADWEEKLY_MEETING_WEEK_1)
+        self.should_be_conflicting(
+            sample_data.BIWEEKLY_ODD_MEETING,
+            sample_data.QUADWEEKLY_MEETING_WEEK_3)
+        self.should_not_conflict(
+            sample_data.BIWEEKLY_ODD_MEETING,
+            sample_data.QUADWEEKLY_MEETING)
+        self.should_not_conflict(
+            sample_data.BIWEEKLY_ODD_MEETING,
+            sample_data.QUADWEEKLY_MEETING_WEEK_2)
+        self.should_not_conflict(
+            sample_data.BIWEEKLY_ODD_MEETING,
+            sample_data.QUADWEEKLY_MEETING_ALTERNATING)
+        self.should_not_conflict(
+            sample_data.QUADWEEKLY_MEETING,
+            sample_data.QUADWEEKLY_MEETING_WEEK_1)
+        self.should_not_conflict(
+            sample_data.QUADWEEKLY_MEETING,
+            sample_data.QUADWEEKLY_MEETING_WEEK_2)
+        self.should_not_conflict(
+            sample_data.QUADWEEKLY_MEETING,
+            sample_data.QUADWEEKLY_MEETING_WEEK_3)
+        self.should_not_conflict(
+            sample_data.QUADWEEKLY_MEETING_WEEK_1,
+            sample_data.QUADWEEKLY_MEETING_WEEK_2)
+        self.should_not_conflict(
+            sample_data.QUADWEEKLY_MEETING_WEEK_1,
+            sample_data.QUADWEEKLY_MEETING_WEEK_3)
+        self.should_not_conflict(
+            sample_data.QUADWEEKLY_MEETING_WEEK_2,
+            sample_data.QUADWEEKLY_MEETING_WEEK_3)
+        self.should_be_conflicting(
+            sample_data.QUADWEEKLY_MEETING,
+            sample_data.QUADWEEKLY_MEETING)
+        self.should_be_conflicting(
+            sample_data.QUADWEEKLY_MEETING_WEEK_1,
+            sample_data.QUADWEEKLY_MEETING_WEEK_1)
+        self.should_be_conflicting(
+            sample_data.QUADWEEKLY_MEETING_WEEK_2,
+            sample_data.QUADWEEKLY_MEETING_WEEK_2)
+        self.should_be_conflicting(
+            sample_data.QUADWEEKLY_MEETING_WEEK_3,
+            sample_data.QUADWEEKLY_MEETING_WEEK_3)
+        self.should_be_conflicting(
+            sample_data.QUADWEEKLY_MEETING_WEEK_2,
+            sample_data.QUADWEEKLY_MEETING_ALTERNATE)
+
     def test_meeting_duration(self):
         m = meeting.load_meetings(sample_data.MEETING_WITH_DURATION)[0]
         self.assertEqual(30, m.schedules[0].duration)

yaml2ical/tests/test_recurrence.py

@@ -38,6 +38,26 @@ class RecurrenceTestCase(unittest.TestCase):
             datetime.datetime(2014, 10, 15, 2, 47, 28, 832666),
             self.next_meeting(recurrence.BiWeeklyRecurrence(style='even')))
 
+    def test_next_quadweekly_week_0(self):
+        self.assertEqual(
+            datetime.datetime(2014, 10, 29, 2, 47, 28, 832666),
+            self.next_meeting(recurrence.QuadWeeklyRecurrence(week=0)))
+
+    def test_next_quadweekly_week_1(self):
+        self.assertEqual(
+            datetime.datetime(2014, 10, 8, 2, 47, 28, 832666),
+            self.next_meeting(recurrence.QuadWeeklyRecurrence(week=1)))
+
+    def test_next_quadweekly_week_2(self):
+        self.assertEqual(
+            datetime.datetime(2014, 10, 15, 2, 47, 28, 832666),
+            self.next_meeting(recurrence.QuadWeeklyRecurrence(week=2)))
+
+    def test_next_quadweekly_week_3(self):
+        self.assertEqual(
+            datetime.datetime(2014, 10, 22, 2, 47, 28, 832666),
+            self.next_meeting(recurrence.QuadWeeklyRecurrence(week=3)))
+
     def test_next_adhoc(self):
         self.assertEqual(
             None,