#! /usr/bin/env python
# -*- coding: utf-8 -*-
# vim:fenc=utf-8
#
# Copyright © 2017 lafrite <lafrite@Poivre>
#
# Distributed under terms of the MIT license.

from mapytex.calculus.core.tree import Tree
from .mo import MO, MOError

__all__ = ["MOFraction"]

class MOFraction(MO):

    """ Fraction math object"""

    def __init__(self, numerator, denominator, negative=False):
        """ Initiate the MOFraction

        It can't be indempotent.

        :param numerator: Numerator of the Fraction
        :param denominator: Denominator of the Fraction
        :param negative: Is the fraction negative (not concidering sign of
        numerator or denominator.

        >>> f = MOFraction(2, 3)
        >>> f
        <MOFraction 2 / 3>
        >>> f = MOFraction(2, 3, negative = True)
        >>> f
        <MOFraction - 2 / 3>
        """
        value = Tree("/",
                MO.factory(numerator),
                MO.factory(denominator),
                )
        MO.__init__(self, value)

        self._numerator = numerator
        self._denominator = denominator
        self.negative = negative

    @property
    def __txt__(self):
        # TODO: fonctionnement temporaire. Il faudrait utilser un moteur de rendu plus fin. |jeu. mars  8 15:26:49 EAT 2018
        try:
            numerator = self._numerator.__txt__
        except AttributeError:
            numerator = str(self._numerator)

        try:
            denominator = self._denominator.__txt__
        except AttributeError:
            denominator = str(self._denominator)
        return "- "*self.negative + f"{numerator} / {denominator}"

    def __add__(self, other):
        """ Overload * for MOFraction

        :param other: any other MO
        :yields: calculus steps and the final yielded value is a MO.


        >>> f = MOFraction(1, 2)
        >>> g = MOFraction(3, 2)
        """
        raise NotImplemented

    def __mul__(self, other):
        raise NotImplemented

    def __truediv__(self, other):
        raise NotImplemented
        
        

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