From 95f83b90d26b374b8c4bc4f597d28e6e86d4e631 Mon Sep 17 00:00:00 2001
From: Sarah Hoffmann <lonvia@denofr.de>
Date: Fri, 23 Oct 2020 10:43:57 +0200
Subject: [PATCH] minor fixes for geometry compuation during boundary ranking

Go back to using centroid when determining if one admin level
is within another. There are cases where boundaries are slightly
misaligned due to mapping errors (not using the same ways in the
relations).

Only declare boundaries the same when they have the same wikidata
tag _and_ have exactly the same geometry. This works around tagging
errors with the wikidata tag, which happen because of automated
edits to the wikidata tag.
---
 sql/functions/placex_triggers.sql           | 13 ++++++++-----
 test/bdd/db/import/rank_computation.feature | 14 ++++++++++++++
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/sql/functions/placex_triggers.sql b/sql/functions/placex_triggers.sql
index 837f8fd3..1e2aac4c 100644
--- a/sql/functions/placex_triggers.sql
+++ b/sql/functions/placex_triggers.sql
@@ -585,16 +585,19 @@ BEGIN
     -- First, check that admin boundaries do not overtake each other rank-wise.
     parent_address_level := 3;
     FOR location IN
-      SELECT rank_address, extratags FROM placex
+      SELECT rank_address,
+             (CASE WHEN extratags ? 'wikidata' and NEW.extratags ? 'wikidata'
+                        and extratags->'wikidata' = NEW.extratags->'wikidata'
+                   THEN ST_Equals(geometry, NEW.geometry)
+                   ELSE false END) as is_same
+      FROM placex
       WHERE osm_type = 'R' and class = 'boundary' and type = 'administrative'
             and admin_level < NEW.admin_level and admin_level > 3
             and rank_address > 0
-            and ST_Covers(geometry, NEW.geometry)
+            and geometry && NEW.centroid and _ST_Covers(geometry, NEW.centroid)
       ORDER BY admin_level desc LIMIT 1
     LOOP
-      IF location.extratags ? 'wikidata' and NEW.extratags ? 'wikidata'
-         and location.extratags->'wikidata' = NEW.extratags->'wikidata'
-      THEN
+      IF location.is_same THEN
         -- Looks like the same boundary is replicated on multiple admin_levels.
         -- Usual tagging in Poland. Remove our boundary from addresses.
         NEW.rank_address := 0;
diff --git a/test/bdd/db/import/rank_computation.feature b/test/bdd/db/import/rank_computation.feature
index beecb366..0fe440ce 100644
--- a/test/bdd/db/import/rank_computation.feature
+++ b/test/bdd/db/import/rank_computation.feature
@@ -101,6 +101,20 @@ Feature: Rank assignment
             | R21    | R20     | 16                  |
             | R22    | R20     | 16                  |
 
+    Scenario: Admin levels cannot overtake each other due to place address ranks even when slightly misaligned
+        Given the named places
+          | osm | class    | type           | admin | extra+place  | geometry |
+          | R20 | boundary | administrative | 6     | town         | (0 0, 0 2, 2 2, 2 0, 0 0) |
+          | R21 | boundary | administrative | 8     |              | (0 0, -0.0001 1, 1 1, 1 0, 0 0) |
+        When importing
+        Then placex contains
+          | object | rank_search | rank_address |
+          | R20    | 12          | 16 |
+          | R21    | 16          | 18 |
+        Then place_addressline contains
+            | object | address | cached_rank_address |
+            | R21    | R20     | 16                  |
+
     Scenario: Admin levels must not be larger than 25
         Given the named places
           | osm | class    | type           | admin | extra+place   | geometry |