#!/usr/bin/env python
"""Module to generate a random string

Attributes:
    LENGTH (int): Defaults to a length of 16
"""

import sys
import logging
import optparse

try:
    import OpenSSL
except ImportError:
    logging.error('Missing PyOpenSSL.')
    logging.debug('Try `pip install pyopenssl`')
    sys.exit(1)

import base64

LENGTH = 16


def generate(length):
    """Simple function to call OpenSSL

    Args:
        length (int): length of string to return
    """
    return base64.encodestring(OpenSSL.rand.bytes(256))[:length]


def main():
    """Main function to call
    """
    parser = optparse.OptionParser()
    parser.add_option('-n', dest='length', default=LENGTH, type=int)
    opts, _ = parser.parse_args()

    print generate(opts.length)


if __name__ == '__main__':
    main()
    sys.exit(0)