-- return a table that contains a string match based on input
-- TODO: implement search for timespan

CREATE OR REPLACE FUNCTION cdb_observatory._OBS_SearchTables(
  search_term text,
  time_span text DEFAULT NULL
)
RETURNS table(tablename text, timespan text)
As $$
DECLARE
  out_var text[];
BEGIN

  IF time_span IS NULL
  THEN
    RETURN QUERY
    EXECUTE
    'SELECT tablename, timespan
       FROM observatory.obs_table t
       JOIN observatory.obs_column_table ct
         ON ct.table_id = t.id
       JOIN observatory.obs_column c
         ON ct.column_id = c.id
       WHERE c.type ILIKE ''geometry''
        AND c.id = $1'
    USING search_term;
  ELSE
    RETURN QUERY
    EXECUTE
    'SELECT tablename, timespan
       FROM observatory.obs_table t
       JOIN observatory.obs_column_table ct
         ON ct.table_id = t.id
       JOIN observatory.obs_column c
         ON ct.column_id = c.id
       WHERE c.type ILIKE ''geometry''
        AND c.id = $1
        AND t.timespan = $2'
    USING search_term, time_span;
  END IF;

END;
$$ LANGUAGE plpgsql IMMUTABLE;

-- Functions used to search the observatory for measures
--------------------------------------------------------------------------------
-- TODO allow the user to specify the boundary to search for measures
--

CREATE OR REPLACE FUNCTION cdb_observatory.OBS_Search(
  search_term text,
  relevant_boundary text DEFAULT null
)
RETURNS TABLE(id text, description text, name text, aggregate text, source text)  as $$
DECLARE
  boundary_term text;
BEGIN
  IF relevant_boundary then
    boundary_term = '';
  else
    boundary_term = '';
  END IF;

  RETURN QUERY
  EXECUTE format($string$
              SELECT id, description,
                name,
                  aggregate,
                  NULL::TEXT source -- TODO use tags
                  FROM observatory.OBS_column
                  where name ilike     '%%' || %L || '%%'
                  or description ilike '%%' || %L || '%%'
                  %s
                $string$, search_term, search_term,boundary_term);
  RETURN;
END
$$ LANGUAGE plpgsql;


-- Functions to return the geometry levels that a point is part of
--------------------------------------------------------------------------------
-- TODO add test response

CREATE OR REPLACE FUNCTION OBS_GetAvailableBoundaries(
  geom geometry(Geometry, 4326),
  timespan text DEFAULT null)
RETURNS TABLE(boundary_id text, description text, time_span text, tablename text)  as $$
DECLARE
  timespan_query TEXT DEFAULT '';
BEGIN

  IF time_span != null THEN
    timespan_query = format('AND timespan = %L', time_span);
  END IF;

  RETURN QUERY
  EXECUTE
  $string$
      select
        column_id,
        obs_column.description,
        timespan,
        tablename
      FROM
        observatory.OBS_table,
        observatory.OBS_column_table,
        observatory.OBS_column
      WHERE
        observatory.OBS_column_table.column_id = observatory.obs_column.id AND
        observatory.OBS_column_table.table_id = observatory.obs_table.id
      AND
        observatory.OBS_column.type='Geometry'
      AND
        $1 && bounds::box2d
  $string$ || timespan_query
  USING geom
  RETURN;
END
$$ LANGUAGE plpgsql;