# Copyright (c) 2021 - present / Neuralmagic, Inc. 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 copy import deepcopy

from onnx import ModelProto

from sparseml.exporters.transforms.onnx_transform import OnnxTransform


class PositionsAdjustmentBase(OnnxTransform):

    POSITIONS_NAME = "positions"  # matches intermediate var name in torch

    @classmethod
    def add_positions_input(cls, model: ModelProto) -> ModelProto:
        """
        Adds positions as an input to the model

        :param model: model to update
        :return: updated model
        """
        # positions tensor should have shape equal to input_ids
        input_ids_info = [
            input_info
            for input_info in model.graph.input
            if input_info.name == "input_ids"
        ][0]
        if not input_ids_info:
            raise RuntimeError(
                f"{cls.__name__} - unable to find 'input_ids' in model input"
            )

        positions_input_info = deepcopy(input_ids_info)
        positions_input_info.name = cls.POSITIONS_NAME
        model.graph.input.append(positions_input_info)
        return model
