#!/usr/bin/env python3
"""Convert raw GTFS txt files into portable GeoPackage layers + a colour table.

STATUS: BLOCKED on download_gtfs.py (no feed URL yet).

Intended outputs (data/processed):
    gtfs_shapes.gpkg   (shapes.txt -> LineString per shape_id, EPSG:4326)
    gtfs_stops.gpkg    (stops.txt -> Point per stop, EPSG:4326)
    route_colors.csv   (route_id, route_short_name, route_type, route_color)

Uses partridge for fast GTFS parsing. prepare.py reads these when present and
falls back to OSM-only data when absent.
"""
import sys
from pathlib import Path

from _common import GTFS_RAW, PROCESSED


def main():
    if not (GTFS_RAW / "routes.txt").exists():
        print(
            "gtfs_to_geopackage: BLOCKED — no GTFS data found in "
            f"{GTFS_RAW}. Run download_gtfs.py first once a feed URL is set.",
            file=sys.stderr,
        )
        sys.exit(2)

    # TODO (when GTFS available):
    #   import partridge as pt
    #   import geopandas as gpd
    #   from shapely.geometry import LineString, Point
    #   feed = pt.load_geo_feed(str(GTFS_RAW))
    #   shapes -> gtfs_shapes.gpkg (LineString per shape_id)
    #   stops  -> gtfs_stops.gpkg
    #   routes -> route_colors.csv (route_id, route_short_name, route_type, route_color)
    print("gtfs_to_geopackage: not yet implemented (GTFS feed unavailable).")
    sys.exit(2)


if __name__ == "__main__":
    main()