# Copyright 2021 The HuggingFace Team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from ctypes import c_float, sizeof
from enum import Enum
from typing import Any, Dict, Iterable


class ParameterFormat(Enum):
    Float = c_float

    @property
    def size(self) -> int:
        """
        Number of byte required for this data type

        Returns:
            Integer > 0
        """
        return sizeof(self.value)


def compute_effective_axis_dimension(dimension: int, fixed_dimension: int, num_token_to_add: int = 0) -> int:
    """

    Args:
        dimension:
        fixed_dimension:
        num_token_to_add:

    Returns:

    """
    # < 0 is possible if using a dynamic axis
    if dimension <= 0:
        dimension = fixed_dimension

    dimension -= num_token_to_add
    return dimension


def compute_serialized_parameters_size(num_parameters: int, dtype: ParameterFormat) -> int:
    """
    Compute the size taken by all the parameters in the given the storage format when serializing the model

    Args:
        num_parameters: Number of parameters to be saved
        dtype: The data format each parameter will be saved

    Returns:
        Size (in byte) taken to save all the parameters
    """
    return num_parameters * dtype.size


def flatten_output_collection_property(name: str, field: Iterable[Any]) -> Dict[str, Any]:
    """
    Flatten any potential nested structure expanding the name of the field with the index of the element within the
    structure.

    Args:
        name: The name of the nested structure
        field: The structure to, potentially, be flattened

    Returns:
        (Dict[str, Any]): Outputs with flattened structure and key mapping this new structure.

    """
    from itertools import chain

    return {f"{name}.{idx}": item for idx, item in enumerate(chain.from_iterable(field))}
