country_name: use separate columns for names from OSM

This allows us to distinguish between base names and imported ones
and consiquently removing imported ones if necessary.

data/country_name.sql

@@ -5,6 +5,7 @@
 CREATE TABLE public.country_name (
     country_code character varying(2),
     name public.hstore,
+    derived_name public.hstore,
     country_default_language_code text,
     partition integer
 );

lib-sql/functions/address_lookup.sql

@@ -108,6 +108,7 @@ CREATE OR REPLACE FUNCTION get_addressdata(in_place_id BIGINT, in_housenumber IN
 DECLARE
   place addressdata_place;
   location RECORD;
+  country RECORD;
   current_rank_address INTEGER;
   location_isaddress BOOLEAN;
 BEGIN
@@ -198,6 +199,16 @@ BEGIN
       WHERE place_id = place.place_id
   LOOP
 --RAISE WARNING '%',location;
+    -- mix in default names for countries
+    IF location.rank_address = 4 and place.country_code is not NULL THEN
+      FOR country IN
+        SELECT coalesce(name, ''::hstore) as name FROM country_name
+          WHERE country_code = place.country_code LIMIT 1
+      LOOP
+        place.name := country.name || place.name;
+      END LOOP;
+    END IF;
+
     IF location.rank_address < 4 THEN
       -- no country locations for ranks higher than country
       place.country_code := NULL::varchar(2);
@@ -272,7 +283,8 @@ BEGIN
   -- If no country was included yet, add the name information from country_name.
   IF current_rank_address > 4 THEN
     FOR location IN
-      SELECT name FROM country_name WHERE country_code = place.country_code LIMIT 1
+      SELECT name || coalesce(derived_name, ''::hstore) as name FROM country_name
+        WHERE country_code = place.country_code LIMIT 1
     LOOP
 --RAISE WARNING '% % %',current_rank_address,searchcountrycode,countryname;
       RETURN NEXT ROW(null, null, null, location.name, 'place', 'country', NULL,

lib-sql/functions/place_triggers.sql

@@ -117,16 +117,6 @@ BEGIN
 
   -- ---- All other place types.
 
-  -- Patch in additional country names
-  IF NEW.admin_level = 2 and NEW.type = 'administrative' and NEW.address ? 'country'
-  THEN
-    FOR country IN
-      SELECT name FROM country_name WHERE country_code = lower(NEW.address->'country')
-    LOOP
-      NEW.name = country.name || NEW.name;
-    END LOOP;
-  END IF;
-
   -- When an area is changed from large to small: log and discard change
   IF existing.geometry is not null AND ST_IsValid(existing.geometry)
     AND ST_Area(existing.geometry) > 0.02

lib-sql/functions/placex_triggers.sql

@@ -1044,16 +1044,22 @@ BEGIN
      AND NEW.class = 'boundary' AND NEW.type = 'administrative'
      AND NEW.country_code IS NOT NULL AND NEW.osm_type = 'R'
   THEN
-    -- Update the list of country names. Adding an additional sanity
-    -- check here: make sure the country does overlap with the area where
-    -- we expect it to be as per static country grid.
+    -- Update the list of country names.
+    -- Only take the name from the largest area for the given country code
+    -- in the hope that this is the authoritive one.
+    -- Also replace any old names so that all mapping mistakes can
+    -- be fixed through regular OSM updates.
     FOR location IN
-      SELECT country_code FROM country_osm_grid
-       WHERE ST_Covers(geometry, NEW.centroid) and country_code = NEW.country_code
+      SELECT osm_id FROM placex
+       WHERE rank_search = 4 and osm_type = 'R'
+             and country_code = NEW.country_code
+       ORDER BY ST_Area(geometry) desc
        LIMIT 1
     LOOP
-      {% if debug %}RAISE WARNING 'Updating names for country '%' with: %', NEW.country_code, NEW.name;{% endif %}
-      UPDATE country_name SET name = name || NEW.name WHERE country_code = NEW.country_code;
+      IF location.osm_id = NEW.osm_id THEN
+        {% if debug %}RAISE WARNING 'Updating names for country '%' with: %', NEW.country_code, NEW.name;{% endif %}
+        UPDATE country_name SET derived_name = NEW.name WHERE country_code = NEW.country_code;
+      END IF;
     END LOOP;
   END IF;