# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1508454369 -7200
# Node ID 3c7f0da08063d59c84abacd7e879605d045910b8
# Parent  ed7239f61458c47693bcd5e5ebb4f101405c30ee
Added conflicting period computation.
Introduced ordering of suggested attendees and periods.
Relaxed the attendee editing test.

diff -r ed7239f61458 -r 3c7f0da08063 imiptools/editing.py
--- a/imiptools/editing.py	Fri Oct 20 00:51:26 2017 +0200
+++ b/imiptools/editing.py	Fri Oct 20 01:06:09 2017 +0200
@@ -23,7 +23,7 @@
 from copy import copy
 from datetime import datetime, timedelta
 from imiptools.client import ClientForObject
-from imiptools.data import get_main_period
+from imiptools.data import get_main_period, uri_items
 from imiptools.dates import end_date_from_calendar, end_date_to_calendar, \
                             format_datetime, get_datetime, \
                             get_datetime_attributes, get_end_of_day, \
@@ -125,12 +125,12 @@
         "Reset the editing state."
 
         self.state = State({
-            "attendees" : lambda: OrderedDict(self.obj.get_items("ATTENDEE") or []),
-            "organiser" : lambda: self.obj.get_value("ORGANIZER"),
-            "periods" : lambda: form_periods_from_periods(self.get_unedited_periods()),
+            "attendees"           : lambda: OrderedDict(self.obj.get_items("ATTENDEE") or []),
+            "organiser"           : lambda: self.obj.get_value("ORGANIZER"),
+            "periods"             : lambda: form_periods_from_periods(self.get_unedited_periods()),
             "suggested_attendees" : self.get_suggested_attendees,
-            "suggested_periods" : self.get_suggested_periods,
-            "summary" : lambda: self.obj.get_value("SUMMARY"),
+            "suggested_periods"   : self.get_suggested_periods,
+            "summary"             : lambda: self.obj.get_value("SUMMARY"),
             })
 
     # Access to stored and current information.
@@ -185,11 +185,16 @@
 
         existing = self.state.get("attendees")
         l = []
+
         for attendee, objects in self.get_counters().items():
             for obj in objects:
                 for suggested, attr in obj.get_items("ATTENDEE"):
                     if suggested not in existing:
                         l.append((attendee, (suggested, attr)))
+
+        # Provide a stable ordering.
+
+        l.sort()
         return l
 
     def get_suggested_periods(self):
@@ -239,8 +244,60 @@
                 for period in removed:
                     suggested.append((attendee, period, "remove"))
 
+        # Provide a stable ordering.
+
+        suggested.sort()
         return suggested
 
+    def get_conflicting_periods(self):
+        periods = self.state.get("periods")
+        attendees = self.state.get("attendees")
+        conflicts = set()
+
+        for attendee, attr in uri_items(attendees.items()):
+            if not attendee:
+                continue
+
+            # If not attending this event, other periods cannot conflict.
+
+            if not attr.get("PARTSTAT") in ("ACCEPTED", "TENTATIVE"):
+                continue
+
+            # Obtain free/busy details for the attendee.
+
+            if attendee == self.user:
+                freebusy = self.store.get_freebusy(attendee)
+            elif attendee:
+                freebusy = self.store.get_freebusy_for_other(self.user, attendee)
+            else:
+                continue
+
+            # Without free/busy information, no conflicts can be determined for
+            # the user.
+
+            if not freebusy:
+                continue
+
+            # Compare the origin of each conflicting period.
+
+            for p in freebusy.have_conflict(periods, True):
+
+                # Ignore transparent periods.
+
+                if p.transp == "ORG":
+                    continue
+
+                # Prevent conflicts with this event's own periods.
+
+                if p.uid == self.uid and (not self.recurrenceid or
+                                          not p.recurrenceid or
+                                          self.recurrenceid == p.recurrenceid):
+                    continue
+
+                conflicts.add(p)
+
+        return conflicts
+
     # Validation methods.
 
     def get_checked_periods(self):
@@ -620,7 +677,7 @@
 
         try:
             attr = attendees[attendee]
-            if self.is_organiser() and not self.obj.is_shared() or not attr:
+            if self.is_organiser() or not attr:
                 return (attendee, attr)
         except IndexError:
             pass