added an sql view to track which indoor feature exists where

server/migrations/20240814012328_indoor-features.down.sql

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+-- Add down migration script here
+
+drop materialized view if exists indoor_features cascade;

server/migrations/20240814012328_indoor-features.up.sql

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+-- Add up migration script here
+CREATE materialized VIEW indoor_features as
+with geometry(gid, geom, tags) as (SELECT way_id as gid, geom, tags
+                                   from indoor_ways
+                                   union
+                                   DISTINCT
+                                   SELECT area_id as gid, geom, tags
+                                   from indoor_polygons
+                                   union
+                                   DISTINCT
+                                   SELECT node_id as gid, geom, tags
+                                   from indoor_nodes),
+     geometry_in_lat_lon(gid, geom, tags) as (SELECT gid, ST_Transform(geom, 4326), tags from geometry),
+     -- clustered to within about ~2m of non-overlapping distance
+     clustered_geometry(gid, group_id, geom, tags)
+         as (SELECT gid,
+                    ST_ClusterWithinWin(geom, 0.00001) OVER () AS group_id,
+                    geom,
+                    tags
+             from geometry_in_lat_lon),
+     clustered_features(group_id, features) AS (SELECT group_id,
+                                                       jsonb_build_object(
+                                                               'type', 'Feature',
+                                                               'id', gid,
+                                                               'geometry', ST_AsGeoJSON(geom)::jsonb,
+                                                               'properties', tags
+                                                       ),
+                                                       geom
+                                                from clustered_geometry),
+     grouped_features(group_id, features, convex_hull) as (SELECT group_id,
+                                                                  jsonb_agg(features),
+                                                                  ST_ConvexHull(ST_Collect(array_agg(geom)))::geometry
+                                                           from clustered_features
+                                                           group by group_id
+                                                           order by group_id)
+SELECT group_id, features, convex_hull
+from grouped_features;
+
+CREATE index indoor_features_hull_idx ON indoor_features USING GIST (convex_hull);
+CREATE unique index indoor_features_group_idx ON indoor_features(group_id);