# -*- coding: utf-8 -*-
'''
    salt.utils.yamldumper
    ~~~~~~~~~~~~~~~~~~~~~

'''
# pylint: disable=W0232
#         class has no __init__ method

from __future__ import absolute_import, print_function, unicode_literals
try:
    from yaml import CDumper as Dumper
    from yaml import CSafeDumper as SafeDumper
except ImportError:
    from yaml import Dumper
    from yaml import SafeDumper

import yaml  # pylint: disable=blacklisted-import
import collections
import salt.utils.context
from salt.utils.odict import OrderedDict

__all__ = ['OrderedDumper', 'SafeOrderedDumper', 'IndentedSafeOrderedDumper',
           'get_dumper', 'dump', 'safe_dump']


class IndentMixin(Dumper):
    '''
    Mixin that improves YAML dumped list readability
    by indenting them by two spaces,
    instead of being flush with the key they are under.
    '''

    def increase_indent(self, flow=False, indentless=False):
        return super(IndentMixin, self).increase_indent(flow, False)


class OrderedDumper(Dumper):
    '''
    A YAML dumper that represents python OrderedDict as simple YAML map.
    '''


class SafeOrderedDumper(SafeDumper):
    '''
    A YAML safe dumper that represents python OrderedDict as simple YAML map.
    '''


class IndentedSafeOrderedDumper(IndentMixin, SafeOrderedDumper):
    '''
    A YAML safe dumper that represents python OrderedDict as simple YAML map,
    and also indents lists by two spaces.
    '''


def represent_ordereddict(dumper, data):
    return dumper.represent_dict(list(data.items()))


def represent_undefined(dumper, data):
    return dumper.represent_scalar(u'tag:yaml.org,2002:null', u'NULL')


OrderedDumper.add_representer(OrderedDict, represent_ordereddict)
SafeOrderedDumper.add_representer(OrderedDict, represent_ordereddict)
SafeOrderedDumper.add_representer(None, represent_undefined)

OrderedDumper.add_representer(
    collections.defaultdict,
    yaml.representer.SafeRepresenter.represent_dict
)
SafeOrderedDumper.add_representer(
    collections.defaultdict,
    yaml.representer.SafeRepresenter.represent_dict
)
OrderedDumper.add_representer(
    salt.utils.context.NamespacedDictWrapper,
    yaml.representer.SafeRepresenter.represent_dict
)
SafeOrderedDumper.add_representer(
    salt.utils.context.NamespacedDictWrapper,
    yaml.representer.SafeRepresenter.represent_dict
)

OrderedDumper.add_representer(
    'tag:yaml.org,2002:timestamp',
    OrderedDumper.represent_scalar)
SafeOrderedDumper.add_representer(
    'tag:yaml.org,2002:timestamp',
    SafeOrderedDumper.represent_scalar)


def get_dumper(dumper_name):
    return {
        'OrderedDumper': OrderedDumper,
        'SafeOrderedDumper': SafeOrderedDumper,
        'IndentedSafeOrderedDumper': IndentedSafeOrderedDumper,
    }.get(dumper_name)


def dump(data, stream=None, **kwargs):
    '''
    .. versionadded:: 2018.3.0

    Helper that wraps yaml.dump and ensures that we encode unicode strings
    unless explicitly told not to.
    '''
    if 'allow_unicode' not in kwargs:
        kwargs['allow_unicode'] = True
    kwargs.setdefault('default_flow_style', None)
    return yaml.dump(data, stream, **kwargs)


def safe_dump(data, stream=None, **kwargs):
    '''
    Use a custom dumper to ensure that defaultdict and OrderedDict are
    represented properly. Ensure that unicode strings are encoded unless
    explicitly told not to.
    '''
    if 'allow_unicode' not in kwargs:
        kwargs['allow_unicode'] = True
    kwargs.setdefault('default_flow_style', None)
    return yaml.dump(data, stream, Dumper=SafeOrderedDumper, **kwargs)
