# Copyright 2017 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,
# 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.
# ==============================================================================
"""Executes Estimator benchmarks and accuracy tests."""

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

import json
import time
import os

from absl import flags
from absl.testing import flagsaver
import tensorflow as tf  # pylint: disable=g-bad-import-order

from official.resnet import cifar10_main as cifar_main

DATA_DIR = '/data/cifar10_data/cifar-10-batches-bin'


class EstimatorCifar10BenchmarkTests(tf.test.Benchmark):
  """Benchmarks and accuracy tests for Estimator ResNet56."""

  local_flags = None

  def __init__(self, output_dir=None):
    self.output_dir = output_dir

  def resnet56_1_gpu(self):
    """Test layers model with Estimator and distribution strategies."""
    self._setup()
    flags.FLAGS.num_gpus = 1
    flags.FLAGS.data_dir = DATA_DIR
    flags.FLAGS.batch_size = 128
    flags.FLAGS.train_epochs = 182
    flags.FLAGS.model_dir = self._get_model_dir('resnet56_1_gpu')
    flags.FLAGS.resnet_size = 56
    flags.FLAGS.dtype = 'fp32'
    self._run_and_report_benchmark()

  def resnet56_fp16_1_gpu(self):
    """Test layers FP16 model with Estimator and distribution strategies."""
    self._setup()
    flags.FLAGS.num_gpus = 1
    flags.FLAGS.data_dir = DATA_DIR
    flags.FLAGS.batch_size = 128
    flags.FLAGS.train_epochs = 182
    flags.FLAGS.model_dir = self._get_model_dir('resnet56_fp16_1_gpu')
    flags.FLAGS.resnet_size = 56
    flags.FLAGS.dtype = 'fp16'
    self._run_and_report_benchmark()

  def resnet56_2_gpu(self):
    """Test layers model with Estimator and dist_strat. 2 GPUs."""
    self._setup()
    flags.FLAGS.num_gpus = 1
    flags.FLAGS.data_dir = DATA_DIR
    flags.FLAGS.batch_size = 128
    flags.FLAGS.train_epochs = 182
    flags.FLAGS.model_dir = self._get_model_dir('resnet56_2_gpu')
    flags.FLAGS.resnet_size = 56
    flags.FLAGS.dtype = 'fp32'
    self._run_and_report_benchmark()

  def resnet56_fp16_2_gpu(self):
    """Test layers FP16 model with Estimator and dist_strat. 2 GPUs."""
    self._setup()
    flags.FLAGS.num_gpus = 2
    flags.FLAGS.data_dir = DATA_DIR
    flags.FLAGS.batch_size = 128
    flags.FLAGS.train_epochs = 182
    flags.FLAGS.model_dir = self._get_model_dir('resnet56_fp16_2_gpu')
    flags.FLAGS.resnet_size = 56
    flags.FLAGS.dtype = 'fp16'
    self._run_and_report_benchmark()

  def unit_test(self):
    """A lightweigth test that can finish quickly"""
    self._setup()
    flags.FLAGS.num_gpus = 1
    flags.FLAGS.data_dir = DATA_DIR
    flags.FLAGS.batch_size = 128
    flags.FLAGS.train_epochs = 1
    flags.FLAGS.model_dir = self._get_model_dir('resnet56_1_gpu')
    flags.FLAGS.resnet_size = 8
    flags.FLAGS.dtype = 'fp32'
    self._run_and_report_benchmark()

  def _run_and_report_benchmark(self):
    start_time_sec = time.time()
    stats = cifar_main.run_cifar(flags.FLAGS)
    wall_time_sec = time.time() - start_time_sec

    self.report_benchmark(
        iters=stats['global_step'],
        wall_time=wall_time_sec,
        extras={
            'accuracy':
                self._json_description(stats['accuracy'].item(), priority=0),
            'accuracy_top_5':
                self._json_description(stats['accuracy_top_5'].item()),
        })

  def _json_description(self,
                        value,
                        priority=None,
                        min_value=None,
                        max_value=None):
    """Get a json-formatted string describing the attributes for a metric"""

    attributes = {}
    attributes['value'] = value
    if priority:
      attributes['priority'] = priority
    if min_value:
      attributes['min_value'] = min_value
    if max_value:
      attributes['max_value'] = max_value

    if min_value or max_value:
      succeeded = True
      if min_value and value < min_value:
        succeeded = False
      if max_value and value > max_value:
        succeeded = False
      attributes['succeeded'] = succeeded

    return json.dumps(attributes)

  def _get_model_dir(self, folder_name):
    return os.path.join(self.output_dir, folder_name)

  def _setup(self):
    tf.logging.set_verbosity(tf.logging.DEBUG)
    if EstimatorCifar10BenchmarkTests.local_flags is None:
      cifar_main.define_cifar_flags()
      # Loads flags to get defaults to then override.
      flags.FLAGS(['foo'])
      saved_flag_values = flagsaver.save_flag_values()
      EstimatorCifar10BenchmarkTests.local_flags = saved_flag_values
      return
    flagsaver.restore_flag_values(EstimatorCifar10BenchmarkTests.local_flags)
