From a9c5064c957674f7ffeb05fcf90bc3c5e8b6e656 Mon Sep 17 00:00:00 2001
From: Schuyler Erle <schuyler@entropyfree.com>
Date: Tue, 30 Aug 2011 17:43:00 -0700
Subject: [PATCH] Revise overlaps() function to be find() function, support
 searching by string alone.

---
 gazetteer/places/models.py | 27 +++++++++++++++++----------
 gazetteer/places/views.py  | 21 ++++++++++++++-------
 2 files changed, 31 insertions(+), 17 deletions(-)

diff --git a/gazetteer/places/models.py b/gazetteer/places/models.py
index 367de31..826a69a 100644
--- a/gazetteer/places/models.py
+++ b/gazetteer/places/models.py
@@ -24,16 +24,23 @@ class FeatureSearchManager(models.GeoManager):
         cursor = connection.cursor()
         cursor.execute("""SELECT set_limit(%f)""" % threshold)
 
-    def overlaps(self, (minx, miny, maxx, maxy), text=None, srid=4326):
-        bbox = Polygon(((minx,miny),(minx,maxy),(maxx,maxy),(maxx,miny),(minx,miny)),srid=srid)
-        if srid != 4326: bbox.transform(4326) # convert to lon/lat
-        qset = models.GeoManager.get_query_set(self).filter(geometry__bboverlaps=bbox)
+    def find(self, bbox=None, text=None, adm1=None, adm2=None srid=4326):
+        qset = self.get_query_set()
+        if bbox:
+            (minx, miny, maxx, maxy) = bbox
+            bbox = Polygon(((minx,miny),(minx,maxy),(maxx,maxy),(maxx,miny),(minx,miny)),srid=srid)
+            if srid != 4326: bbox.transform(4326) # convert to lon/lat
+            qset = qset.filter(geometry__bboverlaps=bbox)
         if text:
             text = text.replace("'", "''") # escape the '
             # use the pg_trgm index
-            qset = qset.extra(select={"similarity":"similarity(preferred_name, '%s')" % text},
-                              where=["preferred_name %%%% '%s'" % text],
+            qset = qset.extra(select={"similarity":"similarity(preferred_name, '%s')"},
+                              select_params=[text],
+                              where=["preferred_name %% '%s'"],
+                              params=[text],
                               order_by=["-similarity"])
+        if adm1: qset = qset.filter(admin1__exact=adm1)
+        if adm2: qset = qset.filter(admin2__exact=adm2)
         return qset
 
 class Feature(models.Model):
@@ -41,8 +48,8 @@ class Feature(models.Model):
     url = models.CharField(max_length=512, unique=True, verbose_name="URI")
     preferred_name = models.CharField(max_length=512)
     feature_type = models.ForeignKey("FeatureType", null=True, blank=True)
-    admin1 = models.CharField(max_length=2, blank=True, verbose_name="State")
-    admin2 = models.CharField(max_length=255, blank=True, verbose_name="County")
+    admin1 = models.CharField(max_length=2, blank=True, verbose_name="State", db_index=True)
+    admin2 = models.CharField(max_length=255, blank=True, verbose_name="County", db_index=True)
     geometry = models.GeometryField()
     is_primary = models.BooleanField(default=True)
     time_frame = models.ForeignKey("TimeFrame", null=True, blank=True)
@@ -60,8 +67,8 @@ class Feature(models.Model):
         return "%s: %s" % (self.feature_type.code, self.feature_type.name,)
     feature_type_name.short_description = "Feature Type"
 
-    def get_geojson(self):
-        geom = json.loads(self.geometry.transform(3785, True).geojson)
+    def get_geojson(self, srid=4326):
+        geom = json.loads(self.geometry.transform(srid, True).geojson)
 
         if self.feature_type is None:
             feature_type = ''
diff --git a/gazetteer/places/views.py b/gazetteer/places/views.py
index 69f5b2a..f097f7f 100644
--- a/gazetteer/places/views.py
+++ b/gazetteer/places/views.py
@@ -11,14 +11,21 @@ def search(request):
 def search_json(request):
     search_term = request.GET.get("search", "")
     bbox = request.GET.get("bbox", False)
-    if not bbox:
-        return render_to_json_response({'error': 'no bbox parameter'})
-    
-    bs = bbox.split(",")
-    bs_param = (float(bs[0]), float(bs[1]), float(bs[2]), float(bs[3]),)
+    country = request.GET.get("adm0", "US") # right now, unused
+    adm1 = request.GET.get("adm1", "")
+    adm2 = request.GET.get("adm2", "")
+    srid = int(request.GET.get("srid", 4326))
 
-    features_qset = Feature.search.overlaps(bs_param, text=search_term, srid=3785)[0:20]
-    features = [f.get_geojson() for f in features_qset]
+    if bbox:
+        try:
+            bbox = map(float, bbox.split(","))
+        except ValueError:
+            bbox = None
+    if not bbox and not search_term:
+        return render_to_json_response({'error': 'must supply either a valid `bbox` or a `search` parameter'})
+
+    features_qset = Feature.search.find(bbox=bbox, text=search_term, adm1=adm1, adm2=adm2, srid=srid)[0:20]
+    features = [f.get_geojson(srid) for f in features_qset]
     d = {
         'type': 'FeatureCollection',
         'features': features