import argparse
import sys
import pandas as pd


class ProgramArgs:

    def __init__(
        self, input_file: str, column: str, output_file: str, count: bool
    ) -> None:
        self.input_file = input_file
        self.column = column
        self.output_file = output_file
        self.count = count


def get_args(args: list[str]) -> ProgramArgs:

    PARSER = argparse.ArgumentParser()
    PARSER.add_argument("--input-file", "--input", "-i", required=True, type=str)
    PARSER.add_argument("--output-file", "--output", "-o", required=True, type=str)
    PARSER.add_argument("--column", "--col", required=True, type=str)
    PARSER.add_argument(
        "--count", "-c", action="store_const", const=True, default=False
    )
    parsed_args, _ = PARSER.parse_known_args(args)

    return ProgramArgs(
        parsed_args.input_file,
        parsed_args.column,
        parsed_args.output_file,
        parsed_args.count,
    )  # type ignore


if __name__ == "__main__":
    ARGS = get_args(sys.argv)

    OUTPUT_FILE = open(ARGS.output_file, "w+", encoding="utf-8")

    # Load the CSV
    df = pd.read_csv(ARGS.input_file)

    # Count occurrences of each unique last part
    item_counts = df[ARGS.column].value_counts()

    # Print the counts
    for item, count in item_counts.items():

        if ARGS.count:
            OUTPUT_FILE.write(f"{item}: {count}\n")
        else:
            OUTPUT_FILE.write(f"{item}\n")