login.py

import re
from sys import argv
from time import time

class Login(object):
    def __init__(self):
        self.r = re.compile('^([a-z]|[a-z][a-z0-9-\.]{0,18}[a-z0-9])$', re.I)
        self.charmap_min = ord('a')
        self.charmap_max = ord('z')
        self.charmap_min_dig = ord('0')
        self.charmap_max_dig = ord('9')
        self.charmap_midle = [i for i in range(ord('a'), ord('z'))] 
        self.charmap_adds = [ord('-'), ord('.')] 
        self.charmap_digits = [i for i in range(ord('0'), ord('9'))]

    def regexp(self, data):
        start_time = time()
        matcher = self.r.match(data) 
        print ('Exec time', time() - start_time)
        return matcher is not None

    def manual(self, data):
        start_time = time()
        data = data.lower()
        if len(data) <= 20:
            f = data[0]
            l = data[-1]
            d = data[1:-1]
            if self.charmap_min <= ord(f) <= self.charmap_max:
                if ord(l) in self.charmap_digits or self.charmap_midle:
                    for element in d:
                        if not (self.charmap_min <= ord(element) <= self.charmap_max\
                                or ord(element) in self.charmap_adds\
                                or ord(element) in self.charmap_digits):
                                    print ('Not matched', time() - start_time)
                                    return False
                    print ('Matched', time() - start_time)
                    return True
        print ('Not matched', time() - start_time)
        return False

def test(mails):
    with open(mails) as f:
        l = Login()
        for mail in f:
            l.manual(mail)
            l.regexp(mail)



if __name__ == '__main__':
    l = Login()
    data = argv[2]
    flag = argv[1]
    if flag == '--regexp':
        print l.regexp(data)
    elif flag == '--naive':
        print l.manual(data)
    elif flag == '--selftest':
        test(data)
    else: 
        raise Exception("flag not matched")