main.py

import argparse
import sys

from file_processing import (
    file_exists,
    get_byte_count,
    get_character_count,
    get_line_count,
    get_word_count,
    process_file,
)


def print_message(filename: str, results: dict) -> None:
    print_order = ["lines", "words", "bytes", "characters"]
    message = []

    for key_to_search in print_order:
        result = results.get(key_to_search, False)

        if result:
            message.append(str(result))

    if filename:
        message.append(filename)

    message_to_print: str = "\t".join(message)
    print(message_to_print)


if __name__ == "__main__":
    parser = argparse.ArgumentParser(
        prog="ccwc",
        description="Finds the number of bytes, words, characters, and multibyte characters in a text file",
    )

    parser.add_argument(
        "-c", "--byte", help="count the number of bytes", action="store_true"
    )
    parser.add_argument(
        "-l", "--line", help="count the number of lines", action="store_true"
    )
    parser.add_argument(
        "-w", "--word", help="count the number of words", action="store_true"
    )
    parser.add_argument(
        "-m", "--char", help="count the number of characters", action="store_true"
    )
    parser.add_argument("filename", nargs="?", help="the filename to be checked")
    args = parser.parse_args()

    if args.filename and not file_exists(args.filename):
        raise argparse.ArgumentTypeError(f"The file {args.filename} does not exist.")

    if args.filename:
        try:
            with open(args.filename, "rb") as f:
                fileAsBytes = f.read()
        except PermissionError:
            print(f"Incorrect permissions for {args.filename}")
            sys.exit(1)
        except OSError:
            print(f"Could not open {args.filename}")
            sys.exit(1)
    else:
        fileAsBytes = sys.stdin.buffer.read()

    funcs_to_run = []

    if not any([args.byte, args.line, args.word, args.char]):
        funcs_to_run.append(get_line_count)
        funcs_to_run.append(get_word_count)
        funcs_to_run.append(get_byte_count)
    else:
        if args.byte:
            funcs_to_run.append(get_byte_count)
        if args.line:
            funcs_to_run.append(get_line_count)
        if args.word:
            funcs_to_run.append(get_word_count)
        if args.char:
            funcs_to_run.append(get_character_count)

    results = process_file(fileAsBytes, funcs_to_run)
    print_message(args.filename, results)