#!/usr/bin/env python3
#
#       This program is free software; you can redistribute it and/or modify
#       it under the terms of the GNU General Public License as published by
#       the Free Software Foundation; either version 3 of the License, or
#       (at your option) any later version.
#
#       This program is distributed in the hope that it will be useful,
#       but WITHOUT ANY WARRANTY; without even the implied warranty of
#       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#       GNU General Public License for more details.
#
#       You should have received a copy of the GNU General Public License
#       along with this program; if not, write to the Free Software
#       Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
#       MA 02110-1301, USA.

"""Simple program to convert from one scale to the other.
Works with Celsius and Fahrenheit.

Written by Cody A. Taylor , better known as 'code_m'
"""

__all__ = ['main', 'argv_opts', 'try_int', 'c_to_f', 'f_to_c']
__author__ = "Cody A. Taylor ( codemister99@yahoo.com )"
__version__ = "3.0"

import sys

def main():
    """Decide which conversion to run or return errors"""
    args = argv_opts()
    if args.__class__.__name__ == "int":
        return args

    temp, scale = args
    if scale == "f":
        print(f_to_c(temp))
    elif scale == "c":
        print(c_to_f(temp))
    else:
        print("Error: Unknown scale... Use 'C' or 'F'.")
        return 1

    return 0

def argv_opts():
    """Get needed args from the user

    Print Errors where needed
    """
    if len(sys.argv) >= 3:
        try:
            temp = float(sys.argv[1])
        except ValueError as err:
            print("Error: temp: {0}".format(err))
            return 1
        scale = sys.argv[2].lower()
        return temp, scale
    else:
        print("Usage: {0} temp scale".format(sys.argv[0]),
              "Description: Quickly convert Fahrenheit to Celsius.",
              "             Quickly convert Celsius to Fahrenheit.",
              "             'temp' is a numerical value",
              "             'scale' is 'C' or 'F' respectively", sep="\n")
        return 0

def try_int(number):
    """Don't use unnessary floats"""
    if number.is_integer():
        return int(number)

    return number

def c_to_f(temp):
    """Take a temp in c and print the equivalent in f"""
    f = (9 / 5)
    f *= temp
    f += 32
    return "{0}{2}C == {1}{2}F".format(try_int(temp), try_int(f), "\N{DEGREE SIGN}")

def f_to_c(temp):
    """Take a temp in f and print the equivalent in c"""
    c = temp
    c -= 32
    c *= (5 / 9)
    return "{0}{2}F == {1}{2}C".format(try_int(temp), try_int(c), "\N{DEGREE SIGN}")

if __name__ == "__main__":
    sys.exit(main())