Add water name layer

layers/water_name/layer.sql

@@ -0,0 +1,10 @@
+CREATE OR REPLACE FUNCTION layer_water_name(bbox geometry, zoom_level integer)
+RETURNS TABLE(osm_id bigint, geometry geometry, name text, name_en text, class text) AS $$
+    SELECT osm_id, geometry, name, name_en, 'lake'::text AS class
+    FROM osm_water_lakeline
+    WHERE geometry && bbox
+      AND name <> ''
+      AND ((zoom_level BETWEEN 10 AND 13 AND LineLabel(zoom_level, NULLIF(name, ''), geometry))
+        OR (zoom_level >= 14))
+    ORDER BY ST_Length(geometry) DESC;
+$$ LANGUAGE SQL IMMUTABLE;