# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1396909593 -7200
# Node ID c3696d680f22fc4bbd1a2ceee361ce57728eadea
# Parent  62f611b64ff264a30911927298b33059790b8e89
Obtain UID and SEQUENCE details in order to select active event revisions.

diff -r 62f611b64ff2 -r c3696d680f22 EventAggregatorSupport/Resources.py
--- a/EventAggregatorSupport/Resources.py	Mon Apr 07 23:16:49 2014 +0200
+++ b/EventAggregatorSupport/Resources.py	Tue Apr 08 00:26:33 2014 +0200
@@ -213,6 +213,26 @@
 
     return new_event_page.getBody()
 
+# Event selection using UID and SEQUENCE information.
+
+def getActiveRevisions(events):
+
+    """
+    Get the event instances with the greatest SEQUENCE number for each UID in
+    the given 'events'.
+    """
+
+    active = {}
+
+    for event in events:
+        uid = event.getEventUID()
+
+        if not active.has_key(uid) or \
+            event.getSequence() > active[uid].getSequence():
+            active[uid] = event
+
+    return active.values()
+
 # Event selection from request parameters.
 
 def getEventsUsingParameters(category_names, search_pattern, remote_sources,
@@ -229,6 +249,7 @@
     pages               = getPagesFromResults(results, request)
     events              = getEventPages(pages).getEvents()
     events             += getEventResources(remote_sources, calendar_start, calendar_end, request).getEvents()
+    events              = getActiveRevisions(events)
     all_shown_events    = getEventsInPeriod(events, getCalendarPeriod(calendar_start, calendar_end))
     earliest, latest    = getEventLimits(all_shown_events)
 
diff -r 62f611b64ff2 -r c3696d680f22 EventAggregatorSupport/Types.py
--- a/EventAggregatorSupport/Types.py	Mon Apr 07 23:16:49 2014 +0200
+++ b/EventAggregatorSupport/Types.py	Tue Apr 08 00:26:33 2014 +0200
@@ -481,7 +481,7 @@
 
                         # Accept other textual data as it is.
 
-                        elif property in ("LOCATION", "SUMMARY", "URL"):
+                        elif property in ("LOCATION", "SUMMARY", "URL", "UID"):
                             value = value or None
 
                         # Ignore other properties.
@@ -525,6 +525,7 @@
         ("categories",      "xcal:properties/xcal:categories",      "getCollection"),
         ("geo",             "xcal:properties/xcal:geo",             "getGeo"),
         ("url",             "xcal:properties/xcal:url",             "getURI"),
+        ("uid",             "xcal:properties/xcal:uid",             "getText"),
         ]
 
     def __init__(self, url, doc, metadata):
@@ -928,6 +929,18 @@
 
         self.page = page
 
+    def getEventUID(self):
+
+        "Return the UID of this event."
+
+        return self.details.get("uid") or self.getEventURL()
+
+    def getSequence(self):
+
+        "Return the sequence number of this event."
+
+        return self.details.get("sequence") or 0
+
     def getEventURL(self):
 
         "Return the URL of this event."
@@ -1108,7 +1121,7 @@
         return {
             "created" : self.details.get("created") or self.details.get("dtstamp") or metadata["created"],
             "last-modified" : self.details.get("last-modified") or self.details.get("dtstamp") or metadata["last-modified"],
-            "sequence" : self.details.get("sequence") or 0,
+            "sequence" : self.getSequence(),
             "last-comment" : ""
             }