metro_rush.py

#!/usr/bin/env python3
from argparse import ArgumentParser
from sys import stderr
from time import time
from moving import MovingTrains


def get_arguments():
    """
    Get and parse arguments from terminal.
    @return: namespace of arguments include:
             - data file name
             - algorithm type
             - visualization
    """
    parser = ArgumentParser(prog='Metro Network',
                            usage='[filename] --algo [ALGO] --gui')
    parser.add_argument('filename', help='A metro stations file')
    parser.add_argument('--algo', nargs='?', metavar='ALGO', default=0,
                        choices=[0, 1], type=int,
                        help='specify which algorithm to use for finding '
                             'the smallest number of turns')
    parser.add_argument('--gui', action='store_true',
                        help='visualize the Metro Network with Pyglet')
    return parser.parse_args()


def read_data_file(filename):
    """
    Read information from data file.
    Save each line to a list.
    @param filename: metro stations file
    @return: list of each line in metro stations file
    """
    try:
        with open(filename, 'r') as file:
            return file.readlines()
    except (FileNotFoundError, PermissionError, IsADirectoryError):
        stderr.write('Invalid file\n')
        exit(1)


def main():
    """Run main program."""
    # Setup start time of program.
    start = time()
    # Get arguments for user input.
    args = get_arguments()
    # Find paths and run trains.
    delhi_metro = MovingTrains(read_data_file(args.filename), args.algo)
    # Print runtime.
    print('\nRuntime: {}s'.format(round(time() - start, 5)))
    # Visualize metro network by Pyglet.
    if args.gui:
        from visualize import GUI
        GUI(delhi_metro)


if __name__ == '__main__':
    try:
        main()
    except Exception as error:
        print(error)