#   Copyright (c) 2022 PaddlePaddle Authors. 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.


# A dict of operators that contain weights and support quantization,
# including operator names, actual input and output names.
SUPPORT_WEIGHT_QUANTIZATION_OP_DICT = {
    "conv2d": [["Input", "Filter"], ["Output"]],
    "depthwise_conv2d": [["Input", "Filter"], ["Output"]],
    "conv2d_transpose": [["Input", "Filter"], ["Output"]],
    "mul": [["X", "Y"], ["Out"]],
    "matmul": [["X", "Y"], ["Out"]],
    "matmul_v2": [["X", "Y"], ["Out"]],
}

# A dict of operators that supports quantization and has only activation inputs,
# including operator names, actual input and output names.
SUPPORT_ACT_QUANTIZATION_OP_DICT = {
    "mul": [["X", "Y"], ["Out"]],
    "matmul": [["X", "Y"], ["Out"]],
    "matmul_v2": [["X", "Y"], ["Out"]],
    "pool2d": [["X"], ["Out"]],
    "elementwise_add": [["X", "Y"], ["Out"]],
    "concat": [["X"], ["Out"]],
    "softmax": [["X"], ["Out"]],
    "argmax": [["X"], ["Out"]],
    "transpose": [["X"], ["Out"]],
    "equal": [["X", "Y"], ["Out"]],
    "gather": [["X"], ["Out"]],
    "greater_equal": [["X", "Y"], ["Out"]],
    "greater_than": [["X", "Y"], ["Out"]],
    "less_equal": [["X", "Y"], ["Out"]],
    "less_than": [["X", "Y"], ["Out"]],
    "mean": [["X"], ["Out"]],
    "not_equal": [["X", "Y"], ["Out"]],
    "reshape": [["X"], ["Out"]],
    "reshape2": [["X"], ["Out"]],
    "transpose2": [["X"], ["Out"]],
    "nearest_interp": [["X"], ["Out"]],
    "trilinear_interp": [["X"], ["Out"]],
    "slice": [["Input"], ["Out"]],
    "squeeze": [["X"], ["Out"]],
    "elementwise_sub": [["X", "Y"], ["Out"]],
    "relu": [["X"], ["Out"]],
    "relu6": [["X"], ["Out"]],
    "leaky_relu": [["X"], ["Out"]],
    "prelu": [["X", "Alpha"], ["Out"]],
    "tanh": [["X"], ["Out"]],
    "swish": [["X"], ["Out"]],
    "dropout": [["X"], ["Out"]],
    "batch_norm": [["X"], ["Y"]],
    "layer_norm": [["X"], ["Y"]],
    "sigmoid": [["X"], ["Out"]],
    "elementwise_mul": [["X", "Y"], ["Out"]],
    "elementwise_pow": [["X", "Y"], ["Out"]],
    "hard_swish": [["X"], ["Out"]],
    "hard_sigmoid": [["X"], ["Out"]],
    "gru": [["Input", "Weight"], ["Hidden"]],
    "lstm": [["Input", "Weight"], ["Hidden"]],
    "pad2d": [["X"], ["Out"]],
    "pad3d": [["X"], ["Out"]],
    "flatten": [["X"], ["Out"]],
    "flatten2": [["X"], ["Out"]],
    "unsqueeze2": [["X"], ["Out"]],
    "flatten_contiguous_range": [["X"], ["Out"]],
    "split": [["X"], ["Out"]],
    "squeeze2": [["X"], ["Out"]],
    "nearest_interp_v2": [["X"], ["Out"]],
    "bilinear_interp": [["X"], ["Out"]],
    "bilinear_interp_v2": [["X"], ["Out"]],
    "fill_constant_batch_size_like": [["Input"], ["Out"]],
    "arg_max": [["X"], ["Out"]],
    "abs": [["X"], ["Out"]],
    "assign": [["X"], ["Out"]],
    "cast": [["X"], ["Out"]],
    "clip": [["X"], ["Out"]],
    "box_coder": [["PriorBox"], ["OutputBox"]],
    "crop": [["X"], ["Out"]],
    "cumsum": [["X"], ["Out"]],
    "expand_v2": [["X"], ["Out"]],
    "fill_any_like": [["X"], ["Out"]],
    "fill_constant": [[], ["Out"]],
    "gelu": [["X"], ["Out"]],
    "instance_norm": [["X"], ["Y"]],
    "lookup_table": [["W", "Ids"], ["Out"]],
    "lookup_table_v2": [["W", "Ids"], ["Out"]],
    "norm": [["X"], ["Norm"]],
    "p_norm": [["X"], ["Out"]],
    "pow": [["X"], ["Out"]],
    "reduce_mean": [["X"], ["Out"]],
    "stack": [["X"], ["Y"]],
    "top_k_v2": [["X"], ["Out", "Indices"]],
    "logical_and": [["X", "Y"], ["Out"]],
    "logical_not": [["X"], ["Out"]],
    "meshgrid": [["X"], ["Out"]],
    "roi_align": [["X", "ROIs"], ["Out"]],
    "strided_slice": [["Input"], ["Out"]],
    "where": [["Condition", "X", "Y"], ["Out"]],
    "grid_sampler": [["X", "Grid"], ["Output"]],
    "tile": [["X"], ["Out"]],
    "group_norm": [["X"], ["Y", "Mean", "Variance"]],
    "reduce_sum": [["X"], ["Out"]],
    "square": [["X"], ["Out"]],
    "softplus": [["X"], ["Out"]],
    "shuffle_channel": [["X"], ["Out"]],
    "reduce_max": [["X"], ["Out"]],
    "scale": [["X"], ["Out"]],
}

# A full dict of operators that supports quantization,
# including operator names, actual input and output names.
SUPPORT_QUANTIZATION_OP_DICT = SUPPORT_WEIGHT_QUANTIZATION_OP_DICT.copy()
SUPPORT_QUANTIZATION_OP_DICT.update(SUPPORT_ACT_QUANTIZATION_OP_DICT)


class BaseQuantizer:
    """
    Basic quantization configuration class, which configures some hyperparameters
    required for quantization, including the list of op types to be quantized,
    quantization bit number for weight and activation and the range of quantization values.
    Args:
        quantizable_op_type(list[str], optional): List the type of ops
            that will be quantized. Default is []. If quantizable_op_type is [],
            it will use the default quantization op type of the qunat config in
            the current Quantizer.
        quant_bits(int, optional): Quantization bit number for weight and activation.
            Default is 8.
    """

    def __init__(
        self,
        quantizable_op_type=[],
        quant_bits=8,
    ):
        self._quantizable_op_type = quantizable_op_type
        self._quant_bits = quant_bits
        self._quant_min = -128
        self._quant_max = 127

    @property
    def weight_quant_operation_types(self):
        """
        Operation type list which should support weight quantization.
        And before these ops, quant dequant nodes will be inserted.
        """
        base_weight_op_type_list = list(
            SUPPORT_WEIGHT_QUANTIZATION_OP_DICT.keys()
        )
        if self._quantizable_op_type:
            weight_list = []
            for _op_type in self._quantizable_op_type:
                if _op_type in base_weight_op_type_list:
                    weight_list.append(_op_type)
            return weight_list
        else:
            return base_weight_op_type_list

    @property
    def activation_quant_operation_types(self):
        """
        Operation type list which should support activation quantization.
        And before these ops, quant dequant nodes will be inserted.
        """
        base_act_op_type_list = list(SUPPORT_ACT_QUANTIZATION_OP_DICT.keys())
        act_quant_op_list = []
        if self._quantizable_op_type:
            for _op_type in self._quantizable_op_type:
                if _op_type in base_act_op_type_list:
                    act_quant_op_list.append(_op_type)
        else:
            act_quant_op_list = [
                'mul',
                'matmul',
                'matmul_v2',
            ]
        return act_quant_op_list

    @property
    def observer_operation_types(self):
        """
        Operation type list for observer in quantization. These nodes only count the
        calibration boundary scale and do not participate in the fake quantization.
        In order to facilitate the deployment of the prediction engine, quant
        and dequant nodes will be inserted after these ops when exporting the model.
        """
        return list(SUPPORT_ACT_QUANTIZATION_OP_DICT.keys())


class TensorRTQuantizer(BaseQuantizer):
    """
    TensorRT quantization configuration class.
    Args:
        quantizable_op_type(list[str], optional): List the type of ops
            that will be quantized. Default is []. If quantizable_op_type is [],
            it will use the default quantization op type of the qunat config in
            the current Quantizer.
        quant_bits(int, optional): Quantization bit number for weight and activation.
            Default is 8.
    """

    def __init__(
        self,
        quantizable_op_type=[],
        quant_bits=8,
    ):
        super().__init__()
        self._quantizable_op_type = quantizable_op_type
        self._quant_bits = quant_bits
        self._quant_min = -128
        self._quant_max = 127

    @property
    def activation_quant_operation_types(self):
        """
        Operation type list which should support activation quantization.
        And before these ops, quant dequant nodes will be inserted.
        """
        return [
            "pool2d",
            "elementwise_add",
            "elementwise_sub",
            "elementwise_mul",
            "elementwise_pow",
            "concat",
            "softmax",
            "argmax",
            "mean",
            "relu",
            "relu6",
            "leaky_relu",
            "tanh",
            "swish",
            "softplus",
            "gelu",
            "hard_sigmoid",
            "hard_swish",
            "sigmoid",
            "layer_norm",
            "matmul_v2",
            "split",
            "bilinear_interp",
            "nearest_interp",
            "trilinear_interp",
            "nearest_interp_v2",
            "bilinear_interp",
            "bilinear_interp_v2",
            "clip",
            "pow",
            "reduce_mean",
            "reduce_sum",
            "reduce_max",
        ]


class ARMCPUQuantizer(BaseQuantizer):
    """
    ARM CPU with Paddle Lite quantization configuration class.
    Args:
        quantizable_op_type(list[str], optional): List the type of ops
            that will be quantized. Default is []. If quantizable_op_type is [],
            it will use the default quantization op type of the qunat config in
            the current Quantizer.
        quant_bits(int, optional): Quantization bit number for weight and activation.
            Default is 8.
    """

    def __init__(
        self,
        quantizable_op_type=[],
        quant_bits=8,
    ):
        super().__init__()
        self._quantizable_op_type = quantizable_op_type
        self._quant_bits = quant_bits
        self._quant_min = -127
        self._quant_max = 127