From c09eb96afdf647efe1845f7e6d8d44a6085f64f6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Denis=20Krienb=C3=BChl?= <denis.krienbuehl@seantis.ch>
Date: Fri, 28 Aug 2015 14:25:40 +0200
Subject: [PATCH] The allocation availability calculation is now faster and
 accurate

---
 HISTORY.rst                     |  3 +++
 onegov/town/utils.py            |  6 +++---
 onegov/town/views/allocation.py | 29 +++++++++++++++++++++++++----
 3 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/HISTORY.rst b/HISTORY.rst
index deed9b8..28f4343 100644
--- a/HISTORY.rst
+++ b/HISTORY.rst
@@ -4,6 +4,9 @@ Changelog
 Unreleased
 ~~~~~~~~~~
 
+- The allocation availability calculation is now faster and accurate.
+  [href]
+
 - Expired reservation sessions are now automatically removed.
   [href]
 
diff --git a/onegov/town/utils.py b/onegov/town/utils.py
index 4b31675..b227304 100644
--- a/onegov/town/utils.py
+++ b/onegov/town/utils.py
@@ -79,9 +79,9 @@ class AllocationEventInfo(object):
 
     __slots__ = ['allocation', 'availability', 'request', 'translate']
 
-    def __init__(self, allocation, request):
+    def __init__(self, allocation, availability, request):
         self.allocation = allocation
-        self.availability = allocation.availability
+        self.availability = availability
         self.request = request
         self.translate = request.translate
 
@@ -118,7 +118,7 @@ def event_title(self):
             }))
         else:
             quota = self.allocation.quota
-            quota_left = self.allocation.quota_left
+            quota_left = int(quota * self.availability / 100)
 
             if quota == 1:
                 if quota_left:
diff --git a/onegov/town/views/allocation.py b/onegov/town/views/allocation.py
index 98a1ca2..a68f43d 100644
--- a/onegov/town/views/allocation.py
+++ b/onegov/town/views/allocation.py
@@ -1,7 +1,9 @@
 import morepath
 
+from itertools import groupby
 from libres.db.models import Allocation
 from libres.modules.errors import LibresError
+from operator import attrgetter
 from onegov.core.security import Public, Private
 from onegov.libres import Resource, ResourceCollection
 from onegov.town import TownApp, _, utils
@@ -30,13 +32,32 @@ def view_allocations_json(self, request):
         return []
 
     scheduler = self.get_scheduler(request.app.libres_context)
+    queries = scheduler.queries
 
-    query = scheduler.allocations_in_range(start, end)
+    # get all allocations (including mirrors), for the availability calculation
+    query = scheduler.allocations_in_range(start, end, masters_only=False)
     query = query.order_by(Allocation._start)
 
-    return [
-        utils.AllocationEventInfo(a, request).as_dict() for a in query.all()
-    ]
+    allocations = query.all()
+
+    # put only return the master allocations
+    events = []
+
+    for key, group in groupby(allocations, key=attrgetter('_start')):
+        grouped = tuple(group)
+        availability = queries.availability_by_allocations(grouped)
+
+        for allocation in grouped:
+            if allocation.is_master:
+                events.append(
+                    utils.AllocationEventInfo(
+                        allocation,
+                        availability,
+                        request
+                    )
+                )
+
+    return [e.as_dict() for e in events]
 
 
 def get_new_allocation_form_class(resource, request):