#!/usr/bin/env python3

"""Create a database containing all S-57 charts in the given directory.

Optionally simplifies the geometries before saving them.
See "S57ChartHandler" for supported nautical chart features.
"""

# Standard library
from argparse import ArgumentDefaultsHelpFormatter
from argparse import ArgumentParser

# Typing
from typing import Optional

# Progress bar
from tqdm import tqdm

# Database and charts
from pyrate.common.charts import S57ChartHandler
from pyrate.common.charts import SpatialiteDatabase


def create_db(path_to_raw_charts: str, path_to_db: str, simplify_tolerance: Optional[float] = None) -> None:
    """Creates a database from all charts in the given directory.

    Args:
        path_to_raw_charts: the path where to look for the source chart files
        path_to_db: the file of the target database
        simplify_tolerance: the tolerance within all new points shall lie wrt. to the old ones, in meters,
                            non-negative
    """
    files = list(S57ChartHandler.find_chart_files(path_to_raw_charts))
    print("Scanned for relevant files")

    with SpatialiteDatabase(path_to_db) as database:
        with database.disable_synchronization():
            if len(database) != 0:
                raise RuntimeError("writing to an already existing database, which might be an error")
            print("Created database")

            handler = S57ChartHandler()
            for file in tqdm(files, unit=" files"):
                database.write_geometries(handler.read_chart_file(file), update=False, raise_on_failure=False)

            if simplify_tolerance is not None:
                vertices_before = database.count_vertices()
                database.simplify_contents(simplify_tolerance)
                vertices_after = database.count_vertices()
                change = (vertices_before - vertices_after) / vertices_before * 100
                print(f"Reduced the vertex count from {vertices_before} to {vertices_after} (-{change:.3f}%)")


def _main() -> None:
    """The main function."""
    parser = ArgumentParser(description=__doc__, formatter_class=ArgumentDefaultsHelpFormatter)
    parser.add_argument("path_to_raw_charts", type=str, help="will be searched recursively")
    parser.add_argument("path_to_db", type=str, help='usually ends with ".sqlite"')
    parser.add_argument(
        "--simplify_tolerance",
        type=float,
        default=25.0,
        help="the simplification tolerance in meters, set to zero to disable",
    )
    args = parser.parse_args()

    simplify_tolerance = None if args.simplify_tolerance == 0.0 else args.simplify_tolerance
    create_db(args.path_to_raw_charts, args.path_to_db, simplify_tolerance)


if __name__ == "__main__":
    _main()