# Copyright 2021 The TensorFlow 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,
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"""Image classification with darknet configs."""

import dataclasses
from typing import List, Optional

from official.core import config_definitions as cfg
from official.core import exp_factory
from official.modeling import hyperparams
from official.vision.beta.configs import common
from official.vision.beta.configs import image_classification as imc
from official.vision.beta.projects.yolo.configs import backbones


@dataclasses.dataclass
class ImageClassificationModel(hyperparams.Config):
  """Image classification model config."""
  num_classes: int = 0
  input_size: List[int] = dataclasses.field(default_factory=lambda: [224, 224])
  backbone: backbones.Backbone = backbones.Backbone(
      type='darknet', darknet=backbones.Darknet())
  dropout_rate: float = 0.0
  norm_activation: common.NormActivation = common.NormActivation()
  # Adds a Batch Normalization layer pre-GlobalAveragePooling in classification.
  add_head_batch_norm: bool = False
  kernel_initializer: str = 'VarianceScaling'


@dataclasses.dataclass
class Losses(hyperparams.Config):
  one_hot: bool = True
  label_smoothing: float = 0.0
  l2_weight_decay: float = 0.0


@dataclasses.dataclass
class ImageClassificationTask(cfg.TaskConfig):
  """The model config."""
  model: ImageClassificationModel = ImageClassificationModel()
  train_data: imc.DataConfig = imc.DataConfig(is_training=True)
  validation_data: imc.DataConfig = imc.DataConfig(is_training=False)
  evaluation: imc.Evaluation = imc.Evaluation()
  losses: Losses = Losses()
  gradient_clip_norm: float = 0.0
  logging_dir: Optional[str] = None


@exp_factory.register_config_factory('darknet_classification')
def darknet_classification() -> cfg.ExperimentConfig:
  """Image classification general."""
  return cfg.ExperimentConfig(
      task=ImageClassificationTask(),
      trainer=cfg.TrainerConfig(),
      restrictions=[
          'task.train_data.is_training != None',
          'task.validation_data.is_training != None'
      ])
