# -*- coding: utf-8 -*-
"""
MolVS - Molecule Validation and Standardization
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

MolVS is a python tool built on top of RDKit that performs validation and standardization of chemical structures.

Note that the C++ reimplementation of this is available in the module rdkit.Chem.MolStandardize.rdMolStandardize

:copyright: (c) 2016 by Matt Swain.
:license: MIT, see LICENSE file for more details.
"""

import logging

from rdkit import Chem
from rdkit.Chem.MolStandardize import rdMolStandardize

from .standardize import Standardizer, standardize_smiles, enumerate_tautomers_smiles, canonicalize_tautomer_smiles
from .validate import Validator, validate_smiles
from .errors import MolVSError, StandardizeError, ValidateError

__title__ = 'MolVS'
__version__ = '0.1.1'
__author__ = 'Matt Swain'
__email__ = 'm.swain@me.com'
__license__ = 'MIT'
__copyright__ = 'Copyright 2016 Matt Swain'

log = logging.getLogger(__name__)
log.addHandler(logging.NullHandler())


def ReorderTautomers(molecule):
    """Returns the list of the molecule's tautomers
    so that the canonical one as determined by the canonical
    scoring system in TautomerCanonicalizer appears first.

    :param molecule: An RDKit Molecule object.
    :return: A list of Molecule objects.
    """
    enumerator = rdMolStandardize.TautomerEnumerator()
    canon = enumerator.Canonicalize(molecule)
    csmi = Chem.MolToSmiles(canon)
    res = [canon]
    tauts = enumerator.Enumerate(molecule)
    smis = [Chem.MolToSmiles(x) for x in tauts]
    stpl = sorted((x, y) for x, y in zip(smis, tauts) if x != csmi)
    res += [y for x, y in stpl]
    return res