gtfs-via-postgres/lib/translations.js

Process GTFS using PostgreSQL.

'use strict'

// https://gtfs.org/schedule/reference/#translationstxt
const beforeAll = (opt) => `\
CREATE OR REPLACE FUNCTION "${opt.schema}".table_exists(
	t_name TEXT
)
RETURNS BOOLEAN
AS $$
	SELECT EXISTS (
		SELECT FROM pg_tables
		WHERE schemaname = '${opt.schema}'
		AND tablename = t_name
		LIMIT 1
	);
$$ LANGUAGE sql STABLE;
${opt.postgraphile ? `\
COMMENT ON FUNCTION "${opt.schema}".table_exists IS E'@omit';
` : ''}

CREATE OR REPLACE FUNCTION "${opt.schema}".column_exists(
	t_name TEXT,
	c_name TEXT
)
RETURNS BOOLEAN
AS $$
	SELECT EXISTS (
		SELECT FROM information_schema.columns
		WHERE table_schema = '${opt.schema}'
		AND table_name = t_name
		AND column_name = c_name
		LIMIT 1
	);
$$ LANGUAGE sql STABLE;
${opt.postgraphile ? `\
COMMENT ON FUNCTION "${opt.schema}".column_exists IS E'@omit';
` : ''}

CREATE TABLE "${opt.schema}"._translations_ref_cols (
	table_name TEXT PRIMARY KEY,
	-- todo: only check if columns exist when table exists?
	record_id_col TEXT NOT NULL
		CONSTRAINT valid_record_id_col CHECK (
			NOT "${opt.schema}".table_exists(table_name)
			OR
			"${opt.schema}".column_exists(table_name, record_id_col)
		),
	record_sub_id_col TEXT
		CONSTRAINT valid_record_sub_id_col CHECK (
			NOT "${opt.schema}".table_exists(table_name)
			OR
			record_sub_id_col IS NULL
			OR
			"${opt.schema}".column_exists(table_name, record_sub_id_col)
		)
);
${opt.postgraphile ? `\
COMMENT ON TABLE "${opt.schema}"._translations_ref_cols IS E'@omit';
` : ''}

-- > ## record_id
-- > Defines the record that corresponds to the field to be translated. The value in record_id must be the first or only field of a table's primary key, as defined in the primary key attribute for each table and below:
-- > - agency_id for agency
-- > - stop_id for stops
-- > - route_id for routes
-- > - trip_id for trips
-- > - trip_id for stop_times
-- > - pathway_id for pathways
-- > - level_id for levels
-- > - attribution_id for attribution
-- > Fields in tables not defined above should not be translated. However producers sometimes add extra fields that are outside the official specification and these unofficial fields may be translated. Below is the recommended way to use record_id for those tables:
-- > - service_id for calendar
-- > - service_id for calendar_dates
-- > - fare_id for fare_attributes
-- > - fare_id for fare_rules
-- > - shape_id for shapes
-- > - trip_id for frequencies
-- > - from_stop_id for transfers
-- > ## record_sub_id
-- > Helps the record that contains the field to be translated when the table doesn’t have a unique ID. Therefore, the value in record_sub_id is the secondary ID of the table, as defined by the table below:
-- > - None for agency.txt
-- > - None for stops.txt
-- > - None for routes.txt
-- > - None for trips.txt
-- > - stop_sequence for stop_times.txt
-- > - None for pathways.txt
-- > - None for levels.txt
-- > - None for attributions.txt
-- > Fields in tables not defined above should not be translated. However producers sometimes add extra fields that are outside the official specification and these unofficial fields may be translated. Below is the recommended way to use record_sub_id for those tables:
-- > - None for calendar.txt
-- > - date for calendar_dates.txt
-- > - None for fare_attributes.txt
-- > - route_id for fare_rules.txt
-- > - None for shapes.txt
-- > - start_time for frequencies.txt
-- > - to_stop_id for transfers.txt
-- https://gtfs.org/schedule/reference/#translationstxt
INSERT INTO "${opt.schema}"._translations_ref_cols (
	table_name,
	record_id_col,
	record_sub_id_col
) VALUES
	-- todo: feed_info
	('agency', 'agency_id', NULL),
	('stops', 'stop_id', NULL),
	('routes', 'route_id', NULL),
	('trips', 'trip_id', NULL),
	('stop_times', 'trip_id', 'stop_sequence'),
	('pathways', 'pathway_id', NULL),
	('levels', 'level_id', NULL),
	('attribution', 'attribution_id', NULL),
	('calendar', 'service_id', NULL),
	('calendar_dates', 'service_id', 'date'),
	('fare_attributes', 'fare_id', NULL),
	('fare_rules', 'fare_id', 'route_id'),
	('shapes', 'shape_id', NULL),
	('frequencies', 'trip_id', 'start_time'),
	('transfers', 'from_stop_id', 'to_stop_id')
;

CREATE OR REPLACE FUNCTION "${opt.schema}".row_exists(
	table_name TEXT,
	col_a_name TEXT,
	col_a_value TEXT,
	col_b_name TEXT,
	col_b_value TEXT
)
RETURNS BOOLEAN
AS $$
	DECLARE
		result BOOLEAN;
	BEGIN
		IF col_b_name IS NULL THEN
			EXECUTE format('
				SELECT EXISTS(
					SELECT *
					FROM %I.%I -- schema, table_name
					WHERE %I = %L -- col_a_name, col_a_value
					LIMIT 1
				)
			', '${opt.schema}', table_name, col_a_name, col_a_value)
			INTO STRICT result;
			RETURN result;
		ELSE
			EXECUTE format('
				SELECT EXISTS(
					SELECT *
					FROM %I.%I -- schema, table_name
					WHERE %I = %L -- col_a_name, col_a_value
					AND %I = %L -- col_b_name, col_b_value
					LIMIT 1
				)
			', '${opt.schema}', table_name, col_a_name, col_a_value, col_b_name, col_b_value)
			INTO STRICT result;
			RETURN result;
		END IF;
	END;
$$ LANGUAGE plpgsql STABLE;
${opt.postgraphile ? `\
COMMENT ON FUNCTION "${opt.schema}".row_exists IS E'@omit';
` : ''}

-- todo: assert that row_exists works as intended
-- SELECT row_exists('stops', 'stop_id', 'de:11000:900120017::2', NULL, NULL); -- Virchowstr. (Berlin)
-- SELECT row_exists('stops', 'stop_name', 'Virchowstr. (Berlin)', NULL, NULL); -- Virchowstr. (Berlin)
-- SELECT row_exists('stops', 'stop_id', 'non-existent', NULL, NULL);
-- SELECT row_exists('stops', 'stop_name', 'non-existent', NULL, NULL);
-- SELECT row_exists('stops', 'stop_id', 'de:11000:900120017::2', 'parent_station', 'de:11000:900120017'); -- Virchowstr. (Berlin) with valid parent_station
-- SELECT row_exists('stops', 'stop_name', 'Virchowstr. (Berlin)', 'parent_station', 'de:11000:900120017'); -- Virchowstr. (Berlin) with valid parent_station
-- SELECT row_exists('stops', 'stop_id', 'de:11000:900120017::2', 'parent_station', 'non-existent'); -- Virchowstr. (Berlin) with invalid parent_station
-- SELECT row_exists('stops', 'stop_name', 'Virchowstr. (Berlin)', 'parent_station', 'non-existent'); -- Virchowstr. (Berlin) with invalid parent_station
-- SELECT row_exists('stops', 'stop_id', 'de:11000:900120017::2', 'non-existent', 'de:11000:900120017'); -- Virchowstr. (Berlin) with invalid column B, should fail
-- SELECT row_exists('stops', 'stop_name', 'Virchowstr. (Berlin)', 'non-existent', 'de:11000:900120017'); -- Virchowstr. (Berlin) with invalid column B, should fail
-- todo: assert that it fails with 2 rows

CREATE OR REPLACE FUNCTION "${opt.schema}".is_valid_translation_ref(
	_table_name TEXT,
	_field_name TEXT,
	_record_id TEXT,
	_record_sub_id TEXT,
	_field_value TEXT
)
RETURNS BOOLEAN
AS $$
	DECLARE
		_record_id_col TEXT;
		_record_sub_id_col TEXT;
		result BOOLEAN;
	BEGIN
		IF _record_id IS NOT NULL THEN
			SELECT record_id_col
			FROM "${opt.schema}"._translations_ref_cols
			WHERE table_name = _table_name
			LIMIT 1
			INTO _record_id_col;
			SELECT record_sub_id_col
			FROM "${opt.schema}"._translations_ref_cols
			WHERE table_name = _table_name
			LIMIT 1
			INTO _record_sub_id_col;

			IF _record_sub_id_col IS NULL AND _record_sub_id IS NOT NULL THEN
				RAISE EXCEPTION
				USING
					MESSAGE = format('record_sub_id must be NULL for %I but is %L', _table_name, _record_sub_id),
					ERRCODE = 'data_exception';
			END IF;
			SELECT "${opt.schema}".row_exists(
				_table_name,
				_record_id_col, _record_id,
				_record_sub_id_col, _record_sub_id
			)
			INTO STRICT result;
			RETURN result;
		ELSEIF _field_value IS NOT NULL THEN
			SELECT "${opt.schema}".row_exists(
				_table_name,
				_field_name, _field_value,
				NULL, NULL
			)
			INTO STRICT result;
			RETURN result;
		ELSE
			RAISE EXCEPTION
			USING
				MESSAGE = 'Either record_id or field_value must be NOT NULL',
				HINT = 'Refer to translations.txt the GTFS Static/Schedule reference.',
				ERRCODE = 'data_exception';
		END IF;
	END;
$$ LANGUAGE plpgsql STABLE;
${opt.postgraphile ? `\
COMMENT ON FUNCTION "${opt.schema}".is_valid_translation_ref IS E'@omit';
` : ''}

-- The MobilityData GTFS Validator just uses Java's Locale#toLanguageTag() to validate "language".
-- https://github.com/MobilityData/gtfs-validator/blob/a11b7489902dd54dc194af1f1515583406ba3716/main/src/main/java/org/mobilitydata/gtfsvalidator/table/GtfsTranslationSchema.java#L36
-- https://docs.oracle.com/javase/7/docs/api/java/util/Locale.html
-- related: https://github.com/google/transit/pull/98

-- https://gtfs.org/schedule/reference/#translationstxt
CREATE TABLE "${opt.schema}".translations (
	-- > Defines the table that contains the field to be translated. Allowed values are:
	-- > agency, stops, routes, trips, stop_times, pathways, levels, feed_info, attributions
	-- > Any file added to GTFS will have a table_name value equivalent to the file name, as listed above (i.e., not including the .txt file extension).
	table_name TEXT NOT NULL,

	-- > Name of the field to be translated. […] Fields with other types should not be translated.
	field_name TEXT NOT NULL
		CONSTRAINT valid_field_name CHECK (
			NOT "${opt.schema}".table_exists(table_name)
			OR
			"${opt.schema}".column_exists(table_name, field_name)
		),

	language TEXT NOT NULL
		CONSTRAINT valid_language CHECK (
			NOT "${opt.schema}".table_exists(table_name)
			OR
			"${opt.schema}".is_valid_lang_code(language)
		),

	translation TEXT NOT NULL,

	-- > Defines the record that corresponds to the field to be translated. The value in record_id must be the first or only field of a table's primary key, as defined in the primary key attribute for each table and below […].
	-- > Fields in tables not defined above should not be translated. However producers sometimes add extra fields that are outside the official specification and these unofficial fields may be translated. […]
	-- > Conditionally Required:
	-- > - Forbidden if table_name is feed_info.
	-- > - Forbidden if field_value is defined.
	-- > - Required if field_value is empty.
	record_id TEXT,

	-- > Helps the record that contains the field to be translated when the table doesn’t have a unique ID. Therefore, the value in record_sub_id is the secondary ID of the table, as defined by the table below:
	-- > - None for agency.txt
	-- > - None for stops.txt
	-- > - None for routes.txt
	-- > - None for trips.txt
	-- > - stop_sequence for stop_times.txt
	-- > - None for pathways.txt
	-- > - None for levels.txt
	-- > - None for attributions.txt
	-- > Fields in tables not defined above should not be translated. However producers sometimes add extra fields that are outside the official specification and these unofficial fields may be translated. Below is the recommended way to use record_sub_id for those tables:
	-- > - None for calendar.txt
	-- > - date for calendar_dates.txt
	-- > - None for fare_attributes.txt
	-- > - route_id for fare_rules.txt
	-- > - None for shapes.txt
	-- > - start_time for frequencies.txt
	-- > - to_stop_id for transfers.txt
	-- > Conditionally Required:
	-- > - Forbidden if table_name is feed_info.
	-- > - Forbidden if field_value is defined.
	-- > - Required if table_name=stop_times and record_id is defined.
	record_sub_id TEXT,

	-- > Instead of […] using record_id and record_sub_id, this field can be used […]. When used, the translation will be applied when the fields identified by table_name and field_name contains the exact same value defined in field_value.
	-- > The field must have exactly the value defined in field_value. If only a subset of the value matches field_value, the translation won’t be applied.
	-- > Conditionally Required:
	-- > - Forbidden if table_name is feed_info.
	-- > - Forbidden if record_id is defined.
	-- > - Required if record_id is empty.
	-- todo:
	-- > If two translation rules match the same record (one with field_value, and the other one with record_id), the rule with record_id takes precedence.
	field_value TEXT,

	CONSTRAINT field_value_or_record_id CHECK (
		field_value IS NULL OR record_id IS NULL
	),
	CONSTRAINT not_with_feed_info CHECK (
		field_value IS NULL OR table_name != 'feed_info'
	),

	CONSTRAINT valid_reference CHECK (
		NOT "${opt.schema}".table_exists(table_name)
		OR
		table_name = 'feed_info'
		OR
		"${opt.schema}".is_valid_translation_ref(
			table_name,
			field_name,
			record_id,
			record_sub_id,
			field_value
		)
	),

	-- > Primary key (table_name, field_name, language, record_id, record_sub_id, field_value)
	-- https://gtfs.org/schedule/reference/#translationstxt
	-- PostgreSQL doesn't allow NULL values for primary key columns, so we use UNIQUE.
	UNIQUE (
		table_name,
		field_name,
		language,
		record_id,
		record_sub_id,
		field_value
	)
);

COPY "${opt.schema}".translations (
	table_name,
	field_name,
	language,
	translation,
	record_id,
	record_sub_id,
	field_value
) FROM STDIN csv;
`

const formatTranslationsRow = (t) => {
	return [
		t.table_name || null,
		t.field_name || null,
		t.language || null,
		t.translation || null,
		t.record_id || null,
		t.record_sub_id || null,
		t.field_value || null,
	]
}

const afterAll = (opt) => `\
\\.

-- todo
CREATE INDEX ON "${opt.schema}".translations (
	table_name,
	field_name,
	language,
	record_id,
	record_sub_id,
	field_value
);

CREATE OR REPLACE VIEW "${opt.schema}".stops_translated AS
SELECT
	-- almost all columns, duh
	-- todo: find a way to use all columns without explicitly enumerating them here
	stop_id,
	stop_code,
	coalesce(stop_n_t.translation, stop_name) as stop_name,
	stop_n_t.language as stop_name_lang, -- todo: fall back to feed_info.feed_lang?
	coalesce(stop_d_t.translation, stop_desc) as stop_desc,
	stop_d_t.language as stop_desc_lang, -- todo: fall back to feed_info.feed_lang?
	stop_loc,
	zone_id,
	coalesce(stop_u_t.translation, stop_url) as stop_url,
	stop_u_t.language as stop_url_lang, -- todo: fall back to feed_info.feed_lang?
	location_type,
	parent_station,
	stop_timezone,
	wheelchair_boarding,
	level_id,
	platform_code
FROM "${opt.schema}".stops s
LEFT JOIN "${opt.schema}".translations stop_n_t ON (
	stop_n_t.table_name = 'stops' AND stop_n_t.field_name = 'stop_name'
	AND (s.stop_id = stop_n_t.record_id OR s.stop_name = stop_n_t.field_value)
)
LEFT JOIN "${opt.schema}".translations stop_d_t ON (
	stop_d_t.table_name = 'stops' AND stop_d_t.field_name = 'stop_desc'
	AND (s.stop_id = stop_d_t.record_id OR s.stop_name = stop_d_t.field_value)
)
LEFT JOIN "${opt.schema}".translations stop_u_t ON (
	stop_u_t.table_name = 'stops' AND stop_u_t.field_name = 'stop_url'
	AND (s.stop_id = stop_u_t.record_id OR s.stop_name = stop_u_t.field_value)
);
${opt.postgraphile ? `\
COMMENT ON VIEW "${opt.schema}".stops_translated IS E'@omit';

CREATE OR REPLACE FUNCTION "${opt.schema}".stops_translated_stop_name (
	stop stops,
	language TEXT
) RETURNS TEXT AS $$
	SELECT coalesce(t.translation, stops.stop_name)
	FROM "${opt.schema}".stops
	JOIN (
		SELECT
			table_name,
			field_name, record_id, field_value,
			language as lang, translation
		FROM "${opt.schema}".translations
	) t ON (
		t.table_name = 'stops' AND t.field_name = 'stop_name'
		AND (stops.stop_id = t.record_id OR stops.stop_name = t.field_value)
	)
	WHERE stops.stop_id = stop.stop_id
	AND t.lang = language
	LIMIT 1;
$$ LANGUAGE sql STABLE STRICT;
` : ''}

CREATE OR REPLACE VIEW "${opt.schema}".routes_translated AS
SELECT
	-- almost all columns, duh
	-- todo: find a way to use all columns without explicitly enumerating them here
	route_id,
	agency_id,
	coalesce(route_s_t.translation, route_short_name) as route_short_name,
	route_s_t.language as route_short_name_lang, -- todo: fall back to feed_info.feed_lang?
	coalesce(route_l_t.translation, route_long_name) as route_long_name,
	route_l_t.language as route_long_name_lang, -- todo: fall back to feed_info.feed_lang?
	coalesce(route_d_t.translation, route_desc) as route_desc,
	route_d_t.language as route_desc_lang, -- todo: fall back to feed_info.feed_lang?
	route_type,
	coalesce(route_u_t.translation, route_url) as route_url,
	route_u_t.language as route_url_lang, -- todo: fall back to feed_info.feed_lang?
	route_color,
	route_text_color,
	route_sort_order
FROM "${opt.schema}".routes r
LEFT JOIN "${opt.schema}".translations route_s_t ON (
	route_s_t.table_name = 'routes' AND route_s_t.field_name = 'route_short_name'
	AND (r.route_id = route_s_t.record_id OR r.route_short_name = route_s_t.field_value)
)
LEFT JOIN "${opt.schema}".translations route_l_t ON (
	route_l_t.table_name = 'routes' AND route_l_t.field_name = 'route_long_name'
	AND (r.route_id = route_l_t.record_id OR r.route_long_name = route_l_t.field_value)
)
LEFT JOIN "${opt.schema}".translations route_d_t ON (
	route_d_t.table_name = 'routes' AND route_d_t.field_name = 'route_desc'
	AND (r.route_id = route_d_t.record_id OR r.route_long_name = route_d_t.field_value)
)
LEFT JOIN "${opt.schema}".translations route_u_t ON (
	route_u_t.table_name = 'routes' AND route_u_t.field_name = 'route_url'
	AND (r.route_id = route_u_t.record_id OR r.route_long_name = route_u_t.field_value)
);
${opt.postgraphile ? `\
COMMENT ON VIEW "${opt.schema}".routes_translated IS E'@omit';

CREATE OR REPLACE FUNCTION "${opt.schema}".routes_translated_route_short_name (
	route routes,
	language TEXT
) RETURNS TEXT AS $$
	SELECT coalesce(t.translation, routes.route_short_name)
	FROM "${opt.schema}".routes
	JOIN (
		SELECT
			table_name,
			field_name, record_id, field_value,
			language as lang, translation
		FROM "${opt.schema}".translations
	) t ON (
		t.table_name = 'routes' AND t.field_name = 'route_short_name'
		AND (routes.route_id = t.record_id OR routes.route_short_name = t.field_value)
	)
	WHERE routes.route_id = route.route_id
	AND t.lang = language
	LIMIT 1;
$$ LANGUAGE sql STABLE STRICT;
CREATE OR REPLACE FUNCTION "${opt.schema}".routes_translated_route_long_name (
	route routes,
	language TEXT
) RETURNS TEXT AS $$
	SELECT coalesce(t.translation, routes.route_long_name)
	FROM "${opt.schema}".routes
	JOIN (
		SELECT
			table_name,
			field_name, record_id, field_value,
			language as lang, translation
		FROM "${opt.schema}".translations
	) t ON (
		t.table_name = 'routes' AND t.field_name = 'route_long_name'
		AND (routes.route_id = t.record_id OR routes.route_long_name = t.field_value)
	)
	WHERE routes.route_id = route.route_id
	AND t.lang = language
	LIMIT 1;
$$ LANGUAGE sql STABLE STRICT;
CREATE OR REPLACE FUNCTION "${opt.schema}".routes_translated_route_desc (
	route routes,
	language TEXT
) RETURNS TEXT AS $$
	SELECT coalesce(t.translation, routes.route_desc)
	FROM "${opt.schema}".routes
	JOIN (
		SELECT
			table_name,
			field_name, record_id, field_value,
			language as lang, translation
		FROM "${opt.schema}".translations
	) t ON (
		t.table_name = 'routes' AND t.field_name = 'route_desc'
		AND (routes.route_id = t.record_id OR routes.route_desc = t.field_value)
	)
	WHERE routes.route_id = route.route_id
	AND t.lang = language
	LIMIT 1;
$$ LANGUAGE sql STABLE STRICT;
CREATE OR REPLACE FUNCTION "${opt.schema}".routes_translated_route_url (
	route routes,
	language TEXT
) RETURNS TEXT AS $$
	SELECT coalesce(t.translation, routes.route_url)
	FROM "${opt.schema}".routes
	JOIN (
		SELECT
			table_name,
			field_name, record_id, field_value,
			language as lang, translation
		FROM "${opt.schema}".translations
	) t ON (
		t.table_name = 'routes' AND t.field_name = 'route_url'
		AND (routes.route_id = t.record_id OR routes.route_url = t.field_value)
	)
	WHERE routes.route_id = route.route_id
	AND t.lang = language
	LIMIT 1;
$$ LANGUAGE sql STABLE STRICT;
` : ''}

-- todo [breaking]: remove in favor of trip_headsign_translations & trip_short_name_translations
CREATE OR REPLACE VIEW "${opt.schema}".trips_translated AS
SELECT
	-- almost all columns, duh
	-- todo: find a way to use all columns without explicitly enumerating them here
	trip_id,
	route_id,
	service_id,
	coalesce(trip_h_t.translation, trip_headsign) as trip_headsign,
	trip_h_t.language as trip_headsign_lang, -- todo: fall back to feed_info.feed_lang?
	coalesce(trip_s_t.translation, trip_short_name) as trip_short_name,
	trip_s_t.language as trip_short_name_lang, -- todo: fall back to feed_info.feed_lang?
	direction_id,
	block_id,
	shape_id,
	wheelchair_accessible,
	bikes_allowed
FROM "${opt.schema}".trips t
LEFT JOIN "${opt.schema}".translations trip_s_t ON (
	trip_s_t.table_name = 'trips' AND trip_s_t.field_name = 'trip_short_name'
	AND (t.trip_id = trip_s_t.record_id OR t.trip_headsign = trip_s_t.field_value)
)
LEFT JOIN "${opt.schema}".translations trip_h_t ON (
	trip_h_t.table_name = 'trips' AND trip_h_t.field_name = 'trip_headsign'
	AND (t.trip_id = trip_h_t.record_id OR t.trip_headsign = trip_h_t.field_value)
);
${opt.postgraphile ? `\
COMMENT ON VIEW "${opt.schema}".trips_translated IS E'@omit';

CREATE OR REPLACE FUNCTION "${opt.schema}".trips_translated_trip_short_name (
	trip trips,
	language TEXT
) RETURNS TEXT AS $$
	SELECT coalesce(t.translation, trips.trip_short_name)
	FROM "${opt.schema}".trips
	JOIN (
		SELECT
			table_name,
			field_name, record_id, field_value,
			language as lang, translation
		FROM "${opt.schema}".translations
	) t ON (
		t.table_name = 'trips' AND t.field_name = 'trip_short_name'
		AND (trips.trip_id = t.record_id OR trips.trip_short_name = t.field_value)
	)
	WHERE trips.trip_id = trip.trip_id
	AND t.lang = language
	LIMIT 1;
$$ LANGUAGE sql STABLE STRICT;
CREATE OR REPLACE FUNCTION "${opt.schema}".trips_translated_trip_headsign (
	trip trips,
	language TEXT
) RETURNS TEXT AS $$
	SELECT coalesce(t.translation, trips.trip_headsign)
	FROM "${opt.schema}".trips
	JOIN (
		SELECT
			table_name,
			field_name, record_id, field_value,
			language as lang, translation
		FROM "${opt.schema}".translations
	) t ON (
		t.table_name = 'trips' AND t.field_name = 'trip_headsign'
		AND (trips.trip_id = t.record_id OR trips.trip_headsign = t.field_value)
	)
	WHERE trips.trip_id = trip.trip_id
	AND t.lang = language
	LIMIT 1;
$$ LANGUAGE sql STABLE STRICT;
` : ''}

CREATE OR REPLACE VIEW "${opt.schema}".arrivals_departures_translated AS
SELECT
	-- almost all columns, duh
	-- todo: find a way to use all columns without explicitly enumerating them here
	route_id,
	coalesce(route_s_t.translation, route_short_name) as route_short_name,
	route_s_t.language as route_short_name_lang, -- todo: fall back to feed_info.feed_lang?
	coalesce(route_l_t.translation, route_long_name) as route_long_name,
	route_l_t.language as route_long_name_lang, -- todo: fall back to feed_info.feed_lang?
	route_type,
	trip_id, direction_id,
	coalesce(trip_t.translation, trip_headsign) as trip_headsign,
	trip_t.language as trip_headsign_lang, -- todo: fall back to feed_info.feed_lang?
	service_id,
	shape_id,
	"date",
	stop_sequence,
	coalesce(stop_times_t.translation, stop_headsign) as stop_headsign,
	stop_times_t.language as stop_headsign_lang, -- todo: fall back to feed_info.feed_lang?
	pickup_type, drop_off_type, shape_dist_traveled, timepoint,
	tz,
	arrival_time, t_arrival,
	departure_time, t_departure,
	stop_id,
	coalesce(stop_t.translation, stop_name) as stop_name,
	stop_t.language as stop_name_lang, -- todo: fall back to feed_info.feed_lang?
	station_id,
	coalesce(station_t.translation, station_name) as station_name,
	station_t.language as station_name_lang -- todo: fall back to feed_info.feed_lang?
FROM "${opt.schema}".arrivals_departures ad
LEFT JOIN "${opt.schema}".translations route_s_t ON (
	route_s_t.table_name = 'routes' AND route_s_t.field_name = 'route_short_name'
	AND (ad.route_id = route_s_t.record_id OR ad.route_short_name = route_s_t.field_value)
)
LEFT JOIN "${opt.schema}".translations route_l_t ON (
	route_l_t.table_name = 'routes' AND route_l_t.field_name = 'route_long_name'
	AND (ad.route_id = route_l_t.record_id OR ad.route_long_name = route_l_t.field_value)
)
LEFT JOIN "${opt.schema}".translations trip_t ON (
	trip_t.table_name = 'trips' AND trip_t.field_name = 'trip_headsign'
	AND (ad.trip_id = trip_t.record_id OR ad.trip_headsign = trip_t.field_value)
)
LEFT JOIN "${opt.schema}".translations stop_t ON (
	stop_t.table_name = 'stops' AND stop_t.field_name = 'stop_name'
	AND (ad.stop_id = stop_t.record_id OR ad.stop_name = stop_t.field_value)
)
LEFT JOIN "${opt.schema}".translations station_t ON (
	station_t.table_name = 'stops' AND station_t.field_name = 'stop_name'
	AND station_t.language = stop_t.language
	AND (ad.station_id = station_t.record_id OR ad.station_name = station_t.field_value)
)
LEFT JOIN "${opt.schema}".translations stop_times_t ON (
	stop_times_t.table_name = 'stop_times' AND stop_times_t.field_name = 'stop_headsign'
	AND (
		(ad.trip_id = stop_times_t.record_id AND ad.stop_sequence = stop_times_t.record_sub_id::integer)
		OR ad.stop_headsign = stop_times_t.field_value
	)
);
${opt.postgraphile ? `\
COMMENT ON VIEW "${opt.schema}".arrivals_departures_translated IS E'@omit';
` : ''}

CREATE OR REPLACE VIEW "${opt.schema}".connections_translated AS
SELECT
	-- almost all columns, duh
	-- todo: find a way to use all columns without explicitly enumerating them here
	route_id,
	coalesce(route_s_t.translation, route_short_name) as route_short_name,
	route_s_t.language as route_short_name_lang, -- todo: fall back to feed_info.feed_lang?
	coalesce(route_l_t.translation, route_long_name) as route_long_name,
	route_l_t.language as route_long_name_lang, -- todo: fall back to feed_info.feed_lang?
	route_type,
	trip_id,
	service_id,
	direction_id,
	coalesce(trip_t.translation, trip_headsign) as trip_headsign,
	trip_t.language as trip_headsign_lang, -- todo: fall back to feed_info.feed_lang?

	from_stop_id,
	coalesce(from_stop.translation, from_stop_name) as from_stop_name,
	from_stop.language as from_stop_name_lang, -- todo: fall back to feed_info.feed_lang?
	from_station_id,
	coalesce(from_station.translation, from_station_name) as from_station_name,
	from_station.language as from_station_name_lang, -- todo: fall back to feed_info.feed_lang?

	coalesce(from_stop_times_t.translation, from_stop_headsign) as from_stop_headsign,
	from_stop_times_t.language as from_stop_headsign_lang, -- todo: fall back to feed_info.feed_lang?
	from_pickup_type,
	t_departure,
	departure_time, -- todo [breaking]: this is misleading, remove it
	from_stop_sequence,
	from_timepoint,

	"date",

	to_timepoint,
	to_stop_sequence,
	t_arrival,
	arrival_time, -- todo [breaking]: this is misleading, remove it
	to_drop_off_type,
	coalesce(to_stop_times_t.translation, to_stop_headsign) as to_stop_headsign,
	to_stop_times_t.language as to_stop_headsign_lang, -- todo: fall back to feed_info.feed_lang?

	to_stop_id,
	coalesce(to_stop.translation, to_stop_name) as to_stop_name,
	to_stop.language as to_stop_name_lang, -- todo: fall back to feed_info.feed_lang?
	to_station_id,
	coalesce(to_station.translation, to_station_name) as to_station_name,
	to_station.language as to_station_name_lang -- todo: fall back to feed_info.feed_lang?
FROM "${opt.schema}".connections c
LEFT JOIN "${opt.schema}".translations route_s_t ON (
	route_s_t.table_name = 'routes' AND route_s_t.field_name = 'route_short_name'
	AND (c.route_id = route_s_t.record_id OR c.route_short_name = route_s_t.field_value)
)
LEFT JOIN "${opt.schema}".translations route_l_t ON (
	route_l_t.table_name = 'routes' AND route_l_t.field_name = 'route_long_name'
	AND (c.route_id = route_l_t.record_id OR c.route_long_name = route_l_t.field_value)
)
LEFT JOIN "${opt.schema}".translations trip_t ON (
	trip_t.table_name = 'trips' AND trip_t.field_name = 'trip_headsign'
	AND (c.trip_id = trip_t.record_id OR c.trip_headsign = trip_t.field_value)
)
LEFT JOIN "${opt.schema}".translations from_stop ON (
	from_stop.table_name = 'stops' AND from_stop.field_name = 'stop_name'
	AND (c.from_stop_id = from_stop.record_id OR c.from_stop_name = from_stop.field_value)
)
LEFT JOIN "${opt.schema}".translations from_station ON (
	from_station.table_name = 'stops' AND from_station.field_name = 'stop_name'
	AND from_station.language = from_stop.language
	AND (c.from_station_id = from_station.record_id OR c.from_station_name = from_station.field_value)
)
LEFT JOIN "${opt.schema}".translations to_stop ON (
	to_stop.table_name = 'stops' AND to_stop.field_name = 'stop_name'
	AND to_stop.language = from_stop.language
	AND (c.to_stop_id = to_stop.record_id OR c.to_stop_name = to_stop.field_value)
)
LEFT JOIN "${opt.schema}".translations to_station ON (
	to_station.table_name = 'stops' AND to_station.field_name = 'stop_name'
	AND to_station.language = from_stop.language
	AND (c.to_station_id = to_station.record_id OR c.to_station_name = to_station.field_value)
)
LEFT JOIN "${opt.schema}".translations from_stop_times_t ON (
	from_stop_times_t.table_name = 'stop_times' AND from_stop_times_t.field_name = 'stop_headsign'
	AND (
		(c.trip_id = from_stop_times_t.record_id AND c.from_stop_sequence = from_stop_times_t.record_sub_id::integer)
		OR c.from_stop_headsign = from_stop_times_t.field_value
	)
)
LEFT JOIN "${opt.schema}".translations to_stop_times_t ON (
	to_stop_times_t.table_name = 'stop_times' AND to_stop_times_t.field_name = 'stop_headsign'
	AND (
		(c.trip_id = to_stop_times_t.record_id AND c.to_stop_sequence = to_stop_times_t.record_sub_id::integer)
		OR c.to_stop_headsign = to_stop_times_t.field_value
	)
);
${opt.postgraphile ? `\
COMMENT ON VIEW "${opt.schema}".connections_translated IS E'@omit';
` : ''}
`

module.exports = {
	beforeAll,
	formatRow: formatTranslationsRow,
	afterAll,
}