CREATE OR REPLACE FUNCTION water_class(waterway text) RETURNS text AS
$$
SELECT CASE
           %%FIELD_MAPPING: class %%
           ELSE 'river'
           END;
$$ LANGUAGE SQL IMMUTABLE
                PARALLEL SAFE;


CREATE OR REPLACE FUNCTION waterway_brunnel(is_bridge bool, is_tunnel bool) RETURNS text AS
$$
SELECT CASE
           WHEN is_bridge THEN 'bridge'
           WHEN is_tunnel THEN 'tunnel'
           END;
$$ LANGUAGE SQL IMMUTABLE
                STRICT
                PARALLEL SAFE;



CREATE OR REPLACE VIEW water_z0 AS
(
-- etldoc:  ne_110m_ocean ->  water_z0
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM ne_110m_ocean
UNION ALL
-- etldoc:  ne_110m_lakes ->  water_z0
SELECT geometry,
       'lake'::text  AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM ne_110m_lakes
    );

CREATE OR REPLACE VIEW water_z1 AS
(
-- etldoc:  ne_110m_ocean ->  water_z1
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM ne_110m_ocean
UNION ALL
-- etldoc:  ne_110m_lakes ->  water_z1
SELECT geometry,
       'lake'::text  AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM ne_110m_lakes
    );

CREATE OR REPLACE VIEW water_z2 AS
(
-- etldoc:  ne_50m_ocean ->  water_z2
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM ne_50m_ocean
UNION ALL
-- etldoc:  ne_50m_lakes ->  water_z2
SELECT geometry,
       'lake'::text  AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM ne_50m_lakes
    );

CREATE OR REPLACE VIEW water_z4 AS
(
-- etldoc:  ne_50m_ocean ->  water_z4
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM ne_50m_ocean
UNION ALL
-- etldoc:  ne_10m_lakes ->  water_z4
SELECT geometry,
       'lake'::text  AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM ne_10m_lakes
    );

CREATE OR REPLACE VIEW water_z5 AS
(
-- etldoc:  ne_10m_ocean ->  water_z5
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM ne_10m_ocean
UNION ALL
-- etldoc:  ne_10m_lakes ->  water_z5
SELECT geometry,
       'lake'::text  AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM ne_10m_lakes
    );

CREATE OR REPLACE VIEW water_z6 AS
(
-- etldoc:  osm_ocean_polygon_gen4 ->  water_z6
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM osm_ocean_polygon_gen4
UNION ALL
-- etldoc:  osm_water_polygon_gen6 ->  water_z6
SELECT geometry,
       water_class(waterway) AS class,
       is_intermittent,
       NULL::boolean         AS is_bridge,
       NULL::boolean         AS is_tunnel
FROM osm_water_polygon_gen6
WHERE "natural" != 'bay'
    );

CREATE OR REPLACE VIEW water_z7 AS
(
-- etldoc:  osm_ocean_polygon_gen4 ->  water_z7
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM osm_ocean_polygon_gen4
UNION ALL
-- etldoc:  osm_water_polygon_gen5 ->  water_z7
SELECT geometry,
       water_class(waterway) AS class,
       is_intermittent,
       NULL::boolean         AS is_bridge,
       NULL::boolean         AS is_tunnel
FROM osm_water_polygon_gen5
WHERE "natural" != 'bay'
    );

CREATE OR REPLACE VIEW water_z8 AS
(
-- etldoc:  osm_ocean_polygon_gen4 ->  water_z8
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM osm_ocean_polygon_gen4
UNION ALL
-- etldoc:  osm_water_polygon_gen4 ->  water_z8
SELECT geometry,
       water_class(waterway) AS class,
       is_intermittent,
       NULL::boolean         AS is_bridge,
       NULL::boolean         AS is_tunnel
FROM osm_water_polygon_gen4
WHERE "natural" != 'bay'
    );

CREATE OR REPLACE VIEW water_z9 AS
(
-- etldoc:  osm_ocean_polygon_gen3 ->  water_z9
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM osm_ocean_polygon_gen3
UNION ALL
-- etldoc:  osm_water_polygon_gen3 ->  water_z9
SELECT geometry,
       water_class(waterway) AS class,
       is_intermittent,
       NULL::boolean         AS is_bridge,
       NULL::boolean         AS is_tunnel
FROM osm_water_polygon_gen3
WHERE "natural" != 'bay'
    );

CREATE OR REPLACE VIEW water_z10 AS
(
-- etldoc:  osm_ocean_polygon_gen2 ->  water_z10
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM osm_ocean_polygon_gen2
UNION ALL
-- etldoc:  osm_water_polygon_gen2 ->  water_z10
SELECT geometry,
       water_class(waterway) AS class,
       is_intermittent,
       NULL::boolean         AS is_bridge,
       NULL::boolean         AS is_tunnel
FROM osm_water_polygon_gen2
WHERE "natural" != 'bay'
    );

CREATE OR REPLACE VIEW water_z11 AS
(
-- etldoc:  osm_ocean_polygon_gen1 ->  water_z11
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM osm_ocean_polygon_gen1
UNION ALL
-- etldoc:  osm_water_polygon_gen1 ->  water_z11
SELECT geometry,
       water_class(waterway) AS class,
       is_intermittent,
       NULL::boolean         AS is_bridge,
       NULL::boolean         AS is_tunnel
FROM osm_water_polygon_gen1
WHERE "natural" != 'bay'
    );

CREATE OR REPLACE VIEW water_z12 AS
(
-- etldoc:  osm_ocean_polygon_gen1 ->  water_z12
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM osm_ocean_polygon
UNION ALL
-- etldoc:  osm_water_polygon ->  water_z12
SELECT geometry,
       water_class(waterway) AS class,
       is_intermittent,
       is_bridge,
       is_tunnel
FROM osm_water_polygon
WHERE "natural" != 'bay'
    );

CREATE OR REPLACE VIEW water_z13 AS
(
-- etldoc:  osm_ocean_polygon ->  water_z13
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM osm_ocean_polygon
UNION ALL
-- etldoc:  osm_water_polygon ->  water_z13
SELECT geometry,
       water_class(waterway) AS class,
       is_intermittent,
       is_bridge,
       is_tunnel
FROM osm_water_polygon
WHERE "natural" != 'bay'
    );

CREATE OR REPLACE VIEW water_z14 AS
(
-- etldoc:  osm_ocean_polygon ->  water_z14
SELECT geometry,
       'ocean'::text AS class,
       NULL::boolean AS is_intermittent,
       NULL::boolean AS is_bridge,
       NULL::boolean AS is_tunnel
FROM osm_ocean_polygon
UNION ALL
-- etldoc:  osm_water_polygon ->  water_z14
SELECT geometry,
       water_class(waterway) AS class,
       is_intermittent,
       is_bridge,
       is_tunnel
FROM osm_water_polygon
WHERE "natural" != 'bay'
    );

-- etldoc: layer_water [shape=record fillcolor=lightpink, style="rounded,filled",
-- etldoc:     label="layer_water |<z0> z0|<z1>z1|<z2>z2|<z3>z3 |<z4> z4|<z5>z5|<z6>z6|<z7>z7| <z8> z8 |<z9> z9 |<z10> z10 |<z11> z11 |<z12> z12|<z13> z13|<z14_> z14+" ] ;

CREATE OR REPLACE FUNCTION layer_water(bbox geometry, zoom_level int)
    RETURNS TABLE
            (
                geometry     geometry,
                class        text,
                brunnel      text,
                intermittent int
            )
AS
$$
SELECT geometry,
       class::text,
       waterway_brunnel(is_bridge, is_tunnel) AS brunnel,
       is_intermittent::int                   AS intermittent
FROM (
         -- etldoc: water_z0 ->  layer_water:z0
         SELECT *
         FROM water_z0
         WHERE zoom_level = 0
         UNION ALL
         -- etldoc: water_z1 ->  layer_water:z1
         SELECT *
         FROM water_z1
         WHERE zoom_level = 1
         UNION ALL
         -- etldoc: water_z2 ->  layer_water:z2
         -- etldoc: water_z2 ->  layer_water:z3
         SELECT *
         FROM water_z2
         WHERE zoom_level BETWEEN 2 AND 3
         UNION ALL
         -- etldoc: water_z4 ->  layer_water:z4
         SELECT *
         FROM water_z4
         WHERE zoom_level = 4
         UNION ALL
         -- etldoc: water_z5 ->  layer_water:z5
         SELECT *
         FROM water_z5
         WHERE zoom_level = 5
         UNION ALL
         -- etldoc: water_z6 ->  layer_water:z6
         SELECT *
         FROM water_z6
         WHERE zoom_level = 6
         UNION ALL
         -- etldoc: water_z7 ->  layer_water:z7
         SELECT *
         FROM water_z7
         WHERE zoom_level = 7
         UNION ALL
         -- etldoc: water_z8 ->  layer_water:z8
         SELECT *
         FROM water_z8
         WHERE zoom_level = 8
         UNION ALL
         -- etldoc: water_z9 ->  layer_water:z9
         SELECT *
         FROM water_z9
         WHERE zoom_level = 9
         UNION ALL
         -- etldoc: water_z10 ->  layer_water:z10
         SELECT *
         FROM water_z10
         WHERE zoom_level = 10
         UNION ALL
         -- etldoc: water_z11 ->  layer_water:z11
         SELECT *
         FROM water_z11
         WHERE zoom_level = 11
         UNION ALL
         -- etldoc: water_z12 ->  layer_water:z12
         SELECT *
         FROM water_z12
         WHERE zoom_level = 12
         UNION ALL
         -- etldoc: water_z13 ->  layer_water:z13
         SELECT *
         FROM water_z13
         WHERE zoom_level = 13
         UNION ALL
         -- etldoc: water_z14 ->  layer_water:z14_
         SELECT *
         FROM water_z14
         WHERE zoom_level >= 14
     ) AS zoom_levels
WHERE geometry && bbox;
$$ LANGUAGE SQL STABLE
                -- STRICT
                PARALLEL SAFE;
