Manage agregation on higher zoom

* json give the needed zoom to have full access on objects
* js reload items when the needed zoom is reach
* on click on aggregated item zoom to the needed zoom to have access to
  items

1 files changed, 40 insertions, 16 deletions

diff --git a/chimere/views.py b/chimere/views.py
index 6e0eb40..8eaa83a 100644
--- a/chimere/views.py
+++ b/chimere/views.py
@@ -749,14 +749,35 @@ def checkDate(q):
 
 
 def _getGeoObjects(area_name, category_ids, status='A', getjson=True,
-                   aggregated=False, item_types=('Marker', 'Route',
-                                                 'Polygon'),
-                   bounding_box=None):
+                   item_types=('Marker', 'Route', 'Polygon'),
+                   bounding_box=None, zoom_level=None):
     '''
     Get geo objects
     '''
+    zoom_need_reload = None
     items = []
     empty = [] if not getjson else {}
+    subcategories = list(
+        SubCategory.getAvailable(None, area_name, public=True,
+                                 instance=True).all())
+    aggregated_category_ids = []
+    try:
+        zoom_level = int(zoom_level)
+    except ValueError:
+        zoom_level = None
+    if zoom_level:
+        # pop from main category list
+        len_subcats = len(subcategories)
+        for idx, subcat in enumerate(reversed(subcategories)):
+            if not subcat.min_zoom:
+                continue
+            if zoom_level < subcat.min_zoom:
+                if not zoom_need_reload or zoom_need_reload > subcat.min_zoom:
+                    zoom_need_reload = subcat.min_zoom
+                aggregated_category_ids.append(
+                    subcategories.pop(len_subcats - 1 - idx).pk)
+
+    category_ids = [subcat.pk for subcat in subcategories]
 
     # marker
     if 'Marker' in item_types:
@@ -767,9 +788,8 @@ def _getGeoObjects(area_name, category_ids, status='A', getjson=True,
                 query = query.filter(point__contained=bounding_box)
             query = query.distinct('pk').order_by('-pk')
         except:
-            return empty
+            return empty, zoom_need_reload
 
-        category_ids = [int(cat_id) for cat_id in category_ids]
         if getjson:
             for geo_object in list(query):
                 items += json.loads(geo_object.getGeoJSON(category_ids))
@@ -785,12 +805,12 @@ def _getGeoObjects(area_name, category_ids, status='A', getjson=True,
                 query = query.filter(polygon__contained=bounding_box)
             query = query.distinct('pk').order_by('-pk')
         except:
-            return empty
+            return empty, zoom_need_reload
 
-        category_ids = [int(cat_id) for cat_id in category_ids]
-        if aggregated:
+        if aggregated_category_ids:
             query = AggregatedPolygon.objects.filter(
-                status__in=status, subcategory__in=category_ids).order_by(
+                status__in=status,
+                subcategory__in=aggregated_category_ids).order_by(
                 'subcategory', '-pk')
             # no bounding box filter
             if getjson:
@@ -840,8 +860,8 @@ def _getGeoObjects(area_name, category_ids, status='A', getjson=True,
             items += list(query)
 
     if not items:
-        return empty
-    return items
+        return empty, zoom_need_reload
+    return items, zoom_need_reload
 
 
 def getGeoObjects(request, area_name, category_ids, status):
@@ -862,12 +882,15 @@ def getGeoObjects(request, area_name, category_ids, status):
         bounding_box.append(value)
     if bounding_box:
         bounding_box = GEOSPolygon.from_bbox(bounding_box)
+    zoom_level = request.GET.get('zoom_level', None)
 
-    jsons = _getGeoObjects(area_name, category_ids, status,
-                           bounding_box=bounding_box)
+    jsons, zoom_need_reload = _getGeoObjects(
+        area_name, category_ids, status, bounding_box=bounding_box,
+        zoom_level=zoom_level)
     if not jsons:
         return HttpResponse("[]", content_type="application/json")
-    data = json.dumps({"type": "FeatureCollection", "features": jsons})
+    data = json.dumps({"type": "FeatureCollection", "features": jsons,
+                       "zoom_need_reload": zoom_need_reload or ''})
     return HttpResponse(data, content_type="application/json")
 
 
@@ -1058,8 +1081,9 @@ class CategoryView(TemplateView):
         if not self.category:
             raise Http404(_("Category does not exist"))
 
-        items = _getGeoObjects(self.area_name, [unicode(self.category.pk)],
-                               getjson=False, item_types=('Marker',))
+        items, zoom_need_reload = _getGeoObjects(
+            self.area_name, [unicode(self.category.pk)], getjson=False,
+            item_types=('Marker',))
         return items
 
     def get_context_data(self, *args, **kwargs):