1.1 --- a/imiptools/data.py	Wed Oct 18 00:57:40 2017 +0200
     1.2 +++ b/imiptools/data.py	Fri Oct 20 22:21:20 2017 +0200
     1.3 @@ -1089,6 +1089,24 @@
     1.4  
     1.5      return delegators
     1.6  
     1.7 +def make_rule_period(start, duration, tzid, attr):
     1.8 +
     1.9 +    """
    1.10 +    Make a period for the rule period starting at 'start' with the given
    1.11 +    'duration' employing the given 'tzid' and datetime 'attr'.
    1.12 +    """
    1.13 +
    1.14 +    # Determine the resolution of the period.
    1.15 +
    1.16 +    create = len(start) == 3 and date or datetime
    1.17 +    start = to_timezone(create(*start), tzid)
    1.18 +    end = start + duration
    1.19 +
    1.20 +    # Create the period with accompanying metadata based on the main
    1.21 +    # period and event details.
    1.22 +
    1.23 +    return RecurringPeriod(start, end, tzid, "RRULE", attr)
    1.24 +
    1.25  def get_periods(obj, tzid, start=None, end=None, inclusive=False):
    1.26  
    1.27      """
    1.28 @@ -1134,7 +1152,7 @@
    1.29  
    1.30          until = parameters.get("UNTIL")
    1.31          if until:
    1.32 -            until_dt = to_timezone(get_datetime(until, dtstart_attr), obj_tzid)
    1.33 +            until_dt = to_timezone(get_datetime(until, dtstart_attr), obj_tzid or tzid)
    1.34              end = end and min(until_dt, end) or until_dt
    1.35              inclusive = True
    1.36  
    1.37 @@ -1148,17 +1166,7 @@
    1.38          # done after the instances have been obtained.
    1.39  
    1.40          for recurrence_start in selector.materialise(dtstart, end, parameters.get("COUNT"), parameters.get("BYSETPOS"), inclusive):
    1.41 -
    1.42 -            # Determine the resolution of the period.
    1.43 -
    1.44 -            create = len(recurrence_start) == 3 and date or datetime
    1.45 -            recurrence_start = to_timezone(create(*recurrence_start), obj_tzid)
    1.46 -            recurrence_end = recurrence_start + main_period.get_duration()
    1.47 -
    1.48 -            # Create the period with accompanying metadata based on the main
    1.49 -            # period and event details.
    1.50 -
    1.51 -            period = RecurringPeriod(recurrence_start, recurrence_end, tzid, "RRULE", dtstart_attr)
    1.52 +            period = make_rule_period(recurrence_start, main_period.get_duration(), obj_tzid or tzid, dtstart_attr)
    1.53  
    1.54              # Filter out periods before the start.
    1.55  
    1.56 @@ -1170,7 +1178,7 @@
    1.57  
    1.58      # Add recurrence dates.
    1.59  
    1.60 -    rdates = obj.get_date_value_item_periods("RDATE", tzid)
    1.61 +    rdates = obj.get_date_value_item_periods("RDATE", obj_tzid or tzid)
    1.62      if rdates:
    1.63          periods += rdates
    1.64  
    1.65 @@ -1180,7 +1188,7 @@
    1.66  
    1.67      # Exclude exception dates.
    1.68  
    1.69 -    exdates = obj.get_date_value_item_periods("EXDATE", tzid)
    1.70 +    exdates = obj.get_date_value_item_periods("EXDATE", obj_tzid or tzid)
    1.71  
    1.72      if exdates:
    1.73          for period in exdates: