-- SPDX-License-Identifier: GPL-2.0-only
--
-- This file is part of Nominatim. (https://nominatim.org)
--
-- Copyright (C) 2022 by the Nominatim developer community.
-- For a full list of authors see the git log.

-- Functions for address interpolation objects in location_property_osmline.


CREATE OR REPLACE FUNCTION get_interpolation_address(in_address HSTORE, wayid BIGINT)
RETURNS HSTORE
  AS $$
DECLARE
  location RECORD;
  waynodes BIGINT[];
BEGIN
  IF in_address ? 'street' or in_address ? 'place' THEN
    RETURN in_address;
  END IF;

  SELECT nodes INTO waynodes FROM planet_osm_ways WHERE id = wayid;
  FOR location IN
    SELECT placex.address, placex.osm_id FROM placex
     WHERE osm_type = 'N' and osm_id = ANY(waynodes)
           and placex.address is not null
           and (placex.address ? 'street' or placex.address ? 'place')
           and indexed_status < 100
  LOOP
    -- mark it as a derived address
    RETURN location.address || in_address || hstore('_inherited', '');
  END LOOP;

  RETURN in_address;
END;
$$
LANGUAGE plpgsql STABLE;



-- find the parent road of the cut road parts
CREATE OR REPLACE FUNCTION get_interpolation_parent(token_info JSONB,
                                                    partition SMALLINT,
                                                    centroid GEOMETRY, geom GEOMETRY)
  RETURNS BIGINT
  AS $$
DECLARE
  parent_place_id BIGINT;
  location RECORD;
BEGIN
  parent_place_id := find_parent_for_address(token_info, partition, centroid);

  IF parent_place_id is null THEN
    FOR location IN SELECT place_id FROM placex
        WHERE ST_DWithin(geom, placex.geometry, 0.001)
              and placex.rank_search = 26
              and placex.osm_type = 'W' -- needed for index selection
        ORDER BY CASE WHEN ST_GeometryType(geom) = 'ST_Line' THEN
                  (ST_distance(placex.geometry, ST_LineInterpolatePoint(geom,0))+
                  ST_distance(placex.geometry, ST_LineInterpolatePoint(geom,0.5))+
                  ST_distance(placex.geometry, ST_LineInterpolatePoint(geom,1)))
                 ELSE ST_distance(placex.geometry, geom) END
              ASC
        LIMIT 1
    LOOP
      parent_place_id := location.place_id;
    END LOOP;
  END IF;

  RETURN parent_place_id;
END;
$$
LANGUAGE plpgsql STABLE;


CREATE OR REPLACE FUNCTION reinsert_interpolation(way_id BIGINT, addr HSTORE,
                                                  geom GEOMETRY)
  RETURNS INT
  AS $$
DECLARE
  existing BIGINT[];
BEGIN
  IF addr is NULL OR NOT addr ? 'interpolation'
         OR NOT (addr->'interpolation' in ('odd', 'even', 'all')
                 or addr->'interpolation' similar to '[1-9]')
  THEN
    -- the new interpolation is illegal, simply remove existing entries
    DELETE FROM location_property_osmline WHERE osm_id = way_id;
  ELSE
    -- Get the existing entry from the interpolation table.
    SELECT array_agg(place_id) INTO existing
      FROM location_property_osmline WHERE osm_id = way_id;

    IF existing IS NULL or array_length(existing, 1) = 0 THEN
      INSERT INTO location_property_osmline (osm_id, address, linegeo)
        VALUES (way_id, addr, geom);
    ELSE
      -- Update the interpolation table:
      --   The first entry gets the original data, all other entries
      --   are removed and will be recreated on indexing.
      --   (An interpolation can be split up, if it has more than 2 address nodes)
      UPDATE location_property_osmline
        SET address = addr,
            linegeo = geom,
            startnumber = null,
            indexed_status = 1
        WHERE place_id = existing[1];
      IF array_length(existing, 1) > 1 THEN
        DELETE FROM location_property_osmline
          WHERE place_id = any(existing[2:]);
      END IF;
    END IF;
  END IF;

  RETURN 1;
END;
$$
LANGUAGE plpgsql;


CREATE OR REPLACE FUNCTION osmline_insert()
  RETURNS TRIGGER
  AS $$
DECLARE
  centroid GEOMETRY;
BEGIN
  NEW.place_id := nextval('seq_place');
  NEW.indexed_date := now();

  IF NEW.indexed_status IS NULL THEN
      IF NEW.address is NULL OR NOT NEW.address ? 'interpolation'
         OR NOT (NEW.address->'interpolation' in ('odd', 'even', 'all')
                 or NEW.address->'interpolation' similar to '[1-9]')
      THEN
          -- alphabetic interpolation is not supported
          RETURN NULL;
      END IF;

      NEW.indexed_status := 1; --STATUS_NEW
      centroid := get_center_point(NEW.linegeo);
      NEW.country_code := lower(get_country_code(centroid));

      NEW.partition := get_partition(NEW.country_code);
      NEW.geometry_sector := geometry_sector(NEW.partition, centroid);
  END IF;

  RETURN NEW;
END;
$$
LANGUAGE plpgsql;


CREATE OR REPLACE FUNCTION osmline_update()
  RETURNS TRIGGER
  AS $$
DECLARE
  waynodes BIGINT[];
  prevnode RECORD;
  nextnode RECORD;
  startnumber INTEGER;
  endnumber INTEGER;
  newstart INTEGER;
  newend INTEGER;
  moddiff SMALLINT;
  linegeo GEOMETRY;
  splitpoint FLOAT;
  sectiongeo GEOMETRY;
  postcode TEXT;
  stepmod SMALLINT;
BEGIN
  -- deferred delete
  IF OLD.indexed_status = 100 THEN
    delete from location_property_osmline where place_id = OLD.place_id;
    RETURN NULL;
  END IF;

  IF NEW.indexed_status != 0 OR OLD.indexed_status = 0 THEN
    RETURN NEW;
  END IF;

  NEW.parent_place_id := get_interpolation_parent(NEW.token_info, NEW.partition,
                                                  get_center_point(NEW.linegeo),
                                                  NEW.linegeo);

  -- Cannot find a parent street. We will not be able to display a reliable
  -- address, so drop entire interpolation.
  IF NEW.parent_place_id is NULL THEN
    DELETE FROM location_property_osmline where place_id = OLD.place_id;
    RETURN NULL;
  END IF;

  NEW.token_info := token_strip_info(NEW.token_info);
  IF NEW.address ? '_inherited' THEN
    NEW.address := hstore('interpolation', NEW.address->'interpolation');
  END IF;

  -- If the line was newly inserted, split the line as necessary.
  IF OLD.indexed_status = 1 THEN
    IF NEW.address->'interpolation' in ('odd', 'even') THEN
      NEW.step := 2;
      stepmod := CASE WHEN NEW.address->'interpolation' = 'odd' THEN 1 ELSE 0 END;
    ELSE
      NEW.step := CASE WHEN NEW.address->'interpolation' = 'all'
                       THEN 1
                       ELSE (NEW.address->'interpolation')::SMALLINT END;
      stepmod := NULL;
    END IF;

    SELECT nodes INTO waynodes
      FROM planet_osm_ways WHERE id = NEW.osm_id;

    IF array_upper(waynodes, 1) IS NULL THEN
      RETURN NEW;
    END IF;

    linegeo := null;
    SELECT null::integer as hnr INTO prevnode;

    -- Go through all nodes on the interpolation line that have a housenumber.
    FOR nextnode IN
      SELECT DISTINCT ON (nodeidpos)
          osm_id, address, geometry,
          -- Take the postcode from the node only if it has a housenumber itself.
          -- Note that there is a corner-case where the node has a wrongly
          -- formatted postcode and therefore 'postcode' contains a derived
          -- variant.
          CASE WHEN address ? 'postcode' THEN placex.postcode ELSE NULL::text END as postcode,
          (address->'housenumber')::integer as hnr
        FROM placex, generate_series(1, array_upper(waynodes, 1)) nodeidpos
        WHERE osm_type = 'N' and osm_id = waynodes[nodeidpos]::BIGINT
              and address is not NULL and address ? 'housenumber'
              and address->'housenumber' ~ '^[0-9]{1,6}$'
              and ST_Distance(NEW.linegeo, geometry) < 0.0005
        ORDER BY nodeidpos
    LOOP
      {% if debug %}RAISE WARNING 'processing point % (%)', nextnode.hnr, ST_AsText(nextnode.geometry);{% endif %}
      IF linegeo is null THEN
        linegeo := NEW.linegeo;
      ELSE
        splitpoint := ST_LineLocatePoint(linegeo, nextnode.geometry);
        IF splitpoint = 0 THEN
          -- Corner case where the splitpoint falls on the first point
          -- and thus would not return a geometry. Skip that section.
          sectiongeo := NULL;
        ELSEIF splitpoint = 1 THEN
          -- Point is at the end of the line.
          sectiongeo := linegeo;
          linegeo := NULL;
        ELSE
          -- Split the line.
          sectiongeo := ST_LineSubstring(linegeo, 0, splitpoint);
          linegeo := ST_LineSubstring(linegeo, splitpoint, 1);
        END IF;
      END IF;

      IF prevnode.hnr is not null
         -- Check if there are housenumbers to interpolate between the
         -- regularly mapped housenumbers.
         -- (Conveniently also fails if one of the house numbers is not a number.)
         and abs(prevnode.hnr - nextnode.hnr) > NEW.step
         -- If the interpolation geometry is broken or two nodes are at the
         -- same place, then splitting might produce a point. Ignore that.
         and ST_GeometryType(sectiongeo) = 'ST_LineString'
      THEN
        IF prevnode.hnr < nextnode.hnr THEN
          startnumber := prevnode.hnr;
          endnumber := nextnode.hnr;
        ELSE
          startnumber := nextnode.hnr;
          endnumber := prevnode.hnr;
          sectiongeo := ST_Reverse(sectiongeo);
        END IF;

        -- Adjust the interpolation, so that only inner housenumbers
        -- are taken into account.
        IF stepmod is null THEN
          newstart := startnumber + NEW.step;
        ELSE
          newstart := startnumber + 1;
          moddiff := newstart % NEW.step - stepmod;
          IF moddiff < 0 THEN
            newstart := newstart + (NEW.step + moddiff);
          ELSE
            newstart := newstart + moddiff;
          END IF;
        END IF;
        newend := newstart + ((endnumber - 1 - newstart) / NEW.step) * NEW.step;

        -- If newstart and newend are the same, then this returns a point.
        sectiongeo := ST_LineSubstring(sectiongeo,
                              (newstart - startnumber)::float / (endnumber - startnumber)::float,
                              (newend - startnumber)::float / (endnumber - startnumber)::float);
        startnumber := newstart;
        endnumber := newend;

        -- determine postcode
        postcode := coalesce(prevnode.postcode, nextnode.postcode, postcode);
        IF postcode is NULL and NEW.parent_place_id > 0 THEN
            SELECT placex.postcode FROM placex
              WHERE place_id = NEW.parent_place_id INTO postcode;
        END IF;
        IF postcode is NULL THEN
            postcode := get_nearest_postcode(NEW.country_code, nextnode.geometry);
        END IF;

        -- Add the interpolation. If this is the first segment, just modify
        -- the interpolation to be inserted, otherwise add an additional one
        -- (marking it indexed already).
        IF NEW.startnumber IS NULL THEN
            NEW.startnumber := startnumber;
            NEW.endnumber := endnumber;
            NEW.linegeo := sectiongeo;
            NEW.postcode := postcode;
        ELSE
          INSERT INTO location_property_osmline
                 (linegeo, partition, osm_id, parent_place_id,
                  startnumber, endnumber, step,
                  address, postcode, country_code,
                  geometry_sector, indexed_status)
          VALUES (sectiongeo, NEW.partition, NEW.osm_id, NEW.parent_place_id,
                  startnumber, endnumber, NEW.step,
                  NEW.address, postcode,
                  NEW.country_code, NEW.geometry_sector, 0);
        END IF;
      END IF;

      -- early break if we are out of line string,
      -- might happen when a line string loops back on itself
      IF linegeo is null or ST_GeometryType(linegeo) != 'ST_LineString' THEN
          RETURN NEW;
      END IF;

      prevnode := nextnode;
    END LOOP;
  END IF;

  RETURN NEW;
END;
$$
LANGUAGE plpgsql;