# Copyright (c) 2021 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.

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

from paddle.utils import try_import

from ppdet.core.workspace import register, serializable
from ppdet.utils.logger import setup_logger
logger = setup_logger(__name__)


@register
@serializable
class QAT(object):
    def __init__(self, quant_config, print_model):
        super(QAT, self).__init__()
        self.quant_config = quant_config
        self.print_model = print_model

    def __call__(self, model):
        paddleslim = try_import('paddleslim')
        self.quanter = paddleslim.dygraph.quant.QAT(config=self.quant_config)
        if self.print_model:
            logger.info("Model before quant:")
            logger.info(model)

        # For PP-YOLOE, convert model to deploy firstly.
        for layer in model.sublayers():
            if hasattr(layer, 'convert_to_deploy'):
                layer.convert_to_deploy()

        self.quanter.quantize(model)

        if self.print_model:
            logger.info("Quantized model:")
            logger.info(model)

        return model

    def save_quantized_model(self, layer, path, input_spec=None, **config):
        self.quanter.save_quantized_model(
            model=layer, path=path, input_spec=input_spec, **config)


@register
@serializable
class PTQ(object):
    def __init__(self,
                 ptq_config,
                 quant_batch_num=10,
                 output_dir='output_inference',
                 fuse=True,
                 fuse_list=None):
        super(PTQ, self).__init__()
        self.ptq_config = ptq_config
        self.quant_batch_num = quant_batch_num
        self.output_dir = output_dir
        self.fuse = fuse
        self.fuse_list = fuse_list

    def __call__(self, model):
        paddleslim = try_import('paddleslim')
        self.ptq = paddleslim.PTQ(**self.ptq_config)
        model.eval()
        quant_model = self.ptq.quantize(
            model, fuse=self.fuse, fuse_list=self.fuse_list)

        return quant_model

    def save_quantized_model(self,
                             quant_model,
                             quantize_model_path,
                             input_spec=None):
        self.ptq.save_quantized_model(quant_model, quantize_model_path,
                                      input_spec)