# Functions to convert between integers and Roman numerals.
# by Paul Winkler
# http://code.activestate.com/recipes/81611-roman-numerals/
# PSFL (GPL compatible)
import os


def int_to_roman(input):
    """
    Convert an integer to Roman numerals.

    Examples:
    >>> int_to_roman(0)
    Traceback (most recent call last):
    ValueError: Argument must be between 1 and 3999

    >>> int_to_roman(-1)
    Traceback (most recent call last):
    ValueError: Argument must be between 1 and 3999

    >>> int_to_roman(1.5)  # doctest: +IGNORE_EXCEPTION_DETAIL
    Traceback (most recent call last):
    TypeError: expected integer, got <type 'float'>

    >>> for i in range(1, 21): print(int_to_roman(i))
    ...
    I
    II
    III
    IV
    V
    VI
    VII
    VIII
    IX
    X
    XI
    XII
    XIII
    XIV
    XV
    XVI
    XVII
    XVIII
    XIX
    XX
    >>> print(int_to_roman(2000))
    MM
    >>> print(int_to_roman(1999))
    MCMXCIX
    """
    if not isinstance(input, int):
        raise TypeError("expected integer, got %s" % type(input))
    if not 0 < input < 4000:
        raise ValueError("Argument must be between 1 and 3999")
    ints = (1000, 900,  500, 400, 100,  90, 50,  40, 10,  9,    5,  4,    1)
    nums = ('M', 'CM', 'D', 'CD', 'C', 'XC', 'L', 'XL', 'X', 'IX', 'V', 'IV',
            'I')
    result = ""
    for i in range(len(ints)):
        count = int(input / ints[i])
        result += nums[i] * count
        input -= ints[i] * count
    return result


def roman_to_int(input):
    """
    Convert a roman numeral to an integer.

    >>> r = list(range(1, 4000))
    >>> nums = [int_to_roman(i) for i in r]
    >>> ints = [roman_to_int(n) for n in nums]
    >>> print(r == ints)
    1

    >>> roman_to_int('VVVIV')
    Traceback (most recent call last):
     ...
    ValueError: input is not a valid roman numeral: VVVIV
    >>> roman_to_int(1)  # doctest: +IGNORE_EXCEPTION_DETAIL
    Traceback (most recent call last):
     ...
    TypeError: expected string, got <type 'int'>
    >>> roman_to_int('a')
    Traceback (most recent call last):
     ...
    ValueError: input is not a valid roman numeral: A
    >>> roman_to_int('IL')
    Traceback (most recent call last):
     ...
    ValueError: input is not a valid roman numeral: IL
    """
    if not isinstance(input, str):
        raise TypeError("expected string, got %s" % type(input))
    input = input.upper()
    nums = ['M', 'D', 'C', 'L', 'X', 'V', 'I']
    ints = [1000, 500, 100, 50,  10,  5,    1]
    places = []
    for c in input:
        if c not in nums:
            raise ValueError("input is not a valid roman numeral: %s" % input)
    for i in range(len(input)):
        c = input[i]
        value = ints[nums.index(c)]
        # If the next place holds a larger number, this value is negative.
        try:
            nextvalue = ints[nums.index(input[i + 1])]
            if nextvalue > value:
                value *= -1
        except IndexError:
            # there is no next place.
            pass
        places.append(value)
    sum = 0
    for n in places:
        sum += n
    # Easiest test for validity...
    if int_to_roman(sum) == input:
        return sum
    else:
        raise ValueError('input is not a valid roman numeral: %s' % input)


def makedirs(path):
    if not os.path.isdir(path):
        os.makedirs(path)


def get_translation(language):
    import gettext
    from .functions import lang_code_3to2

    return gettext.translation(
        'messages',
        localedir=os.path.join(os.path.dirname(__file__), 'locale'),
        languages=[lang_code_3to2(language), 'pl'],
    )