#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
Implementacja narzedzia ``wc`` z linuksa (word counter).
Zwraca liczbę słów, znaków i linii.
"""

import sys
import argparse


def count_lines(text):
    """ return number of lines. """
    return len(text.strip().split('\n'))

def count_words(text):
    """ return number of words. """
    return sum([len([1 for word in line.split(' ') if len(word)])
                for line in text.split('\n')])

def count_chars(text):
    """ return number of words. """
    return len(text)

def wc(text):
    """ proper wc """
    lines = count_lines(text)
    words = count_words(text)
    chars = count_chars(text)
    return lines, words, chars

#Moja klasa wyjątku
class ArgException(Exception):
    def __init__(self, text):
        self.text = text
    def __str__(self):
        return self.text

def main():
    """ main """
    msg_usage = "Usage: task04.py [-h | -l | -w | -c] [file_name | stdin]"
    parser = argparse.ArgumentParser()
    parser.add_argument("-l", help="-l returns number of lines", action = 'store_true')
    parser.add_argument("-w", help="-w returns number of words", action = 'store_true')
    parser.add_argument("-c", help="-c returns number of characters", action = 'store_true')
    parser.add_argument("file_name", help="This is path to the text input file to read the lines from or stdin if not given", type = argparse.FileType('rt'), nargs='?')
    args = parser.parse_args()
    if args.l + args.w + args.c > 1: #Jeśli więcej niż 1 argument {-l, -w, -c}
        print(msg_usage, "\nToo many arguments passed!")
        #print(args.l, args.w, args.c, args.input)
        return

    res = "" #Zwracany napis

    if args.file_name is None:
        fh_lines = sys.stdin.read()
    else:
        fh_lines = args.file_name.read()

    if args.l:
        res = count_lines(fh_lines)
    elif args.w:
        res = count_words(fh_lines)
    elif args.c:
        res = count_chars(fh_lines)
    elif not (args.l and args.w and args.c):
        res = wc(fh_lines)
    else: #Coś jest nie tak!
        raise ArgException(msg_usage, "\nError in arguments!")

    #print(wc(sys.stdin.read()))
    # print(wc(fh_lines))

    #print(fh_lines)
    print(res)

if __name__ == "__main__":
    main()