#
#  Copyright 2020, by the California Institute of Technology.  ALL RIGHTS
#  RESERVED. United States Government Sponsorship acknowledged. Any commercial
#  use must be negotiated with the Office of Technology Transfer at the
#  California Institute of Technology.
#
"""
=======
util.py
=======

Utility functions for the PDS DOI API service.
This module is adapted from the SwaggerHub auto-generated util.py.
"""
import datetime
import typing
from collections import Iterable

import six


def format_exceptions(exceptions):
    """
    Formats a listing of exceptions into a JSON-friendly representation suitable
    for return in an HTTP response.

    Parameters
    ----------
    exceptions : Exception or list or tuple of Exception
        The listing of exceptions to format. A single Exception instance may
        be provided as well.

    Returns
    -------
    formatted_exceptions : dict
        The provided exceptions in the following format:

        ```python
        {
            'errors': [
                {
                    'name': <Exception class name>,
                    'message': <Exception message>
                },
                ...
            ]
        }
        ```

    """
    # Check if we were given a single exception, rather than a listing
    if not isinstance(exceptions, Iterable):
        exceptions = [exceptions]

    return {"errors": [{"name": type(exception).__name__, "message": str(exception)} for exception in exceptions]}


def _deserialize(data, klass):
    """Deserializes dict, list, str into an object.

    :param data: dict, list or str.
    :param klass: class literal, or string of class name.

    :return: object.
    """
    if data is None:
        return None

    if klass in six.integer_types or klass in (float, str, bool):
        return _deserialize_primitive(data, klass)
    elif klass == object:
        return _deserialize_object(data)
    elif klass == datetime.date:
        return deserialize_date(data)
    elif klass == datetime.datetime:
        return deserialize_datetime(data)
    elif type(klass) == typing.GenericMeta:
        if klass.__extra__ == list:
            return _deserialize_list(data, klass.__args__[0])
        if klass.__extra__ == dict:
            return _deserialize_dict(data, klass.__args__[1])
    else:
        return deserialize_model(data, klass)


def _deserialize_primitive(data, klass):
    """Deserializes to primitive type.

    :param data: data to deserialize.
    :param klass: class literal.

    :return: int, long, float, str, bool.
    :rtype: int | long | float | str | bool
    """
    try:
        value = klass(data)
    except UnicodeEncodeError:
        value = six.u(data)
    except TypeError:
        value = data
    return value


def _deserialize_object(value):
    """Return a original value.

    :return: object.
    """
    return value


def deserialize_date(string):
    """Deserializes string to date.

    :param string: str.
    :type string: str
    :return: date.
    :rtype: date
    """
    try:
        from dateutil.parser import parse

        return parse(string).date()
    except ImportError:
        return string


def deserialize_datetime(string):
    """Deserializes string to datetime.

    The string should be in iso8601 datetime format.

    :param string: str.
    :type string: str
    :return: datetime.
    :rtype: datetime
    """
    try:
        from dateutil.parser import parse

        return parse(string)
    except ImportError:
        return string


def deserialize_model(data, klass):
    """Deserializes list or dict to model.

    :param data: dict, list.
    :type data: dict | list
    :param klass: class literal.
    :return: model object.
    """
    instance = klass()

    if not instance.swagger_types:
        return data

    for attr, attr_type in six.iteritems(instance.swagger_types):
        if data is not None and instance.attribute_map[attr] in data and isinstance(data, (list, dict)):
            value = data[instance.attribute_map[attr]]
            setattr(instance, attr, _deserialize(value, attr_type))

    return instance


def _deserialize_list(data, boxed_type):
    """Deserializes a list and its elements.

    :param data: list to deserialize.
    :type data: list
    :param boxed_type: class literal.

    :return: deserialized list.
    :rtype: list
    """
    return [_deserialize(sub_data, boxed_type) for sub_data in data]


def _deserialize_dict(data, boxed_type):
    """Deserializes a dict and its elements.

    :param data: dict to deserialize.
    :type data: dict
    :param boxed_type: class literal.

    :return: deserialized dict.
    :rtype: dict
    """
    return {k: _deserialize(v, boxed_type) for k, v in six.iteritems(data)}
