num2word.py

'''
Adopted from https://stackoverflow.com/questions/19504350/how-to-convert-numbers-to-words-without-using-num2word-library for Turkish
'''

import re


ones = {
    0: '', 1: 'bir', 2: 'iki', 3: 'üç', 4: 'dört', 5: 'beş', 6: 'altı',
    7: 'yedi', 8: 'sekiz', 9: 'dokuz', 10: 'on', 11: 'onbir', 12: 'oniki',
    13: 'onüç', 14: 'ondört', 15: 'onbeş', 16: 'onaltı',
    17: 'onyedi', 18: 'onsekiz', 19: 'ondokuz'}
tens = {
    2: 'yirmi', 3: 'otuz', 4: 'kırk', 5: 'elli', 6: 'atmış',
    7: 'yetmiş', 8: 'seksen', 9: 'doksan'}
illions = {
    1: 'bin', 2: 'milyon', 3: 'milyar', 4: 'trilyon', 5: 'katrilyon'}



def say_number(i):
    """
    Convert an integer in to it's word representation.

    say_number(i: integer) -> string
    """
    if i < 0:
        return _join('eksi', _say_number_pos(-i))
    if i == 0:
        return 'sıfır'
    
    text = _say_number_pos(i)
    text = re.sub('bir yüz', 'yüz', text)
    text = re.sub('^bir bin', 'bin', text)
    return text


def _say_number_pos(i):
    if i < 20:
        return ones[i]
    if i < 100:
        return _join(tens[i // 10], ones[i % 10])
    if i < 1000:
        return _divide(i, 100, 'yüz')
    for illions_number, illions_name in illions.items():
        if i < 1000**(illions_number + 1):
            break
    return _divide(i, 1000**illions_number, illions_name)


def _divide(dividend, divisor, magnitude):
    return _join(
        _say_number_pos(dividend // divisor),
        magnitude,
        _say_number_pos(dividend % divisor),
    )


def _join(*args):
    return ' '.join(filter(bool, args))