# -*- coding: utf-8 -*-
"""Utilities common to CIFAR10 and CIFAR100 datasets.
"""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import sys
from six.moves import cPickle


def load_batch(fpath, label_key='labels'):
    """Internal utility for parsing CIFAR data.

    # Arguments
        fpath: path the file to parse.
        label_key: key for label data in the retrieve
            dictionary.

    # Returns
        A tuple `(data, labels)`.
    """
    with open(fpath, 'rb') as f:
        if sys.version_info < (3,):
            d = cPickle.load(f)
        else:
            d = cPickle.load(f, encoding='bytes')
            # decode utf8
            d_decoded = {}
            for k, v in d.items():
                d_decoded[k.decode('utf8')] = v
            d = d_decoded
    data = d['data']
    labels = d[label_key]

    data = data.reshape(data.shape[0], 3, 32, 32)
    return data, labels