From 4a30ec28b9f5be3851289d1eb0bf1fe5228e5b6b Mon Sep 17 00:00:00 2001
From: Sarah Hoffmann <lonvia@denofr.de>
Date: Fri, 10 Apr 2020 11:05:11 +0200
Subject: [PATCH 1/1] move helper functions from placex_triggers into utils

Also adds documentation for these functions.
---
 sql/functions/placex_triggers.sql | 40 ----------------------
 sql/functions/utils.sql           | 57 +++++++++++++++++++++++++++++++
 2 files changed, 57 insertions(+), 40 deletions(-)

diff --git a/sql/functions/placex_triggers.sql b/sql/functions/placex_triggers.sql
index c04aef28..19367db4 100644
--- a/sql/functions/placex_triggers.sql
+++ b/sql/functions/placex_triggers.sql
@@ -1,45 +1,5 @@
 -- Trigger functions for the placex table.
 
-CREATE OR REPLACE FUNCTION get_rel_node_members(members TEXT[], memberLabels TEXT[])
-  RETURNS SETOF BIGINT
-  AS $$
-DECLARE
-  i INTEGER;
-BEGIN
-  FOR i IN 1..ARRAY_UPPER(members,1) BY 2 LOOP
-    IF members[i+1] = ANY(memberLabels)
-       AND upper(substring(members[i], 1, 1))::char(1) = 'N'
-    THEN
-      RETURN NEXT substring(members[i], 2)::bigint;
-    END IF;
-  END LOOP;
-
-  RETURN;
-END;
-$$
-LANGUAGE plpgsql IMMUTABLE;
-
--- copy 'name' to or from the default language (if there is a default language)
-CREATE OR REPLACE FUNCTION add_default_place_name(country_code VARCHAR(2),
-                                                  INOUT name HSTORE)
-  AS $$
-DECLARE
-  default_language VARCHAR(10);
-BEGIN
-  IF name is not null AND array_upper(akeys(name),1) > 1 THEN
-    default_language := get_country_language_code(country_code);
-    IF default_language IS NOT NULL THEN
-      IF name ? 'name' AND NOT name ? ('name:'||default_language) THEN
-        name := name || hstore(('name:'||default_language), (name -> 'name'));
-      ELSEIF name ? ('name:'||default_language) AND NOT name ? 'name' THEN
-        name := name || hstore('name', (name -> ('name:'||default_language)));
-      END IF;
-    END IF;
-  END IF;
-END;
-$$
-LANGUAGE plpgsql IMMUTABLE;
-
 -- Find the parent road of a POI.
 --
 -- \returns Place ID of parent object or NULL if none
diff --git a/sql/functions/utils.sql b/sql/functions/utils.sql
index 6371e9ad..ccb6a203 100644
--- a/sql/functions/utils.sql
+++ b/sql/functions/utils.sql
@@ -38,6 +38,63 @@ END;
 $$
 LANGUAGE plpgsql IMMUTABLE;
 
+-- Return the node members with a given label from a relation member list
+-- as a set.
+--
+-- \param members      Member list in osm2pgsql middle format.
+-- \param memberLabels Array of labels to accept.
+--
+-- \returns Set of OSM ids of nodes that are found.
+--
+CREATE OR REPLACE FUNCTION get_rel_node_members(members TEXT[],
+                                                memberLabels TEXT[])
+  RETURNS SETOF BIGINT
+  AS $$
+DECLARE
+  i INTEGER;
+BEGIN
+  FOR i IN 1..ARRAY_UPPER(members,1) BY 2 LOOP
+    IF members[i+1] = ANY(memberLabels)
+       AND upper(substring(members[i], 1, 1))::char(1) = 'N'
+    THEN
+      RETURN NEXT substring(members[i], 2)::bigint;
+    END IF;
+  END LOOP;
+
+  RETURN;
+END;
+$$
+LANGUAGE plpgsql IMMUTABLE;
+
+-- Copy 'name' to or from the default language.
+--
+-- \param country_code     Country code of the object being named.
+-- \param[inout] name      List of names of the object.
+--
+-- If the country named by country_code has a single default language,
+-- then a `name` tag is copied to `name:<country_code>` if this tag does
+-- not yet exist and vice versa.
+CREATE OR REPLACE FUNCTION add_default_place_name(country_code VARCHAR(2),
+                                                  INOUT name HSTORE)
+  AS $$
+DECLARE
+  default_language VARCHAR(10);
+BEGIN
+  IF name is not null AND array_upper(akeys(name),1) > 1 THEN
+    default_language := get_country_language_code(country_code);
+    IF default_language IS NOT NULL THEN
+      IF name ? 'name' AND NOT name ? ('name:'||default_language) THEN
+        name := name || hstore(('name:'||default_language), (name -> 'name'));
+      ELSEIF name ? ('name:'||default_language) AND NOT name ? 'name' THEN
+        name := name || hstore('name', (name -> ('name:'||default_language)));
+      END IF;
+    END IF;
+  END IF;
+END;
+$$
+LANGUAGE plpgsql IMMUTABLE;
+
+
 
 CREATE OR REPLACE FUNCTION reverse_place_diameter(rank_search SMALLINT)
   RETURNS FLOAT
-- 
2.39.5