# Copyright 2023 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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"""Tests for movinet.py."""

from absl.testing import parameterized
import tensorflow as tf, tf_keras

from official.projects.movinet.modeling import movinet


class MoViNetTest(parameterized.TestCase, tf.test.TestCase):

  def test_network_creation(self):
    """Test creation of MoViNet family models."""
    tf_keras.backend.set_image_data_format('channels_last')

    network = movinet.Movinet(
        model_id='a0',
        causal=True,
    )
    inputs = tf_keras.Input(shape=(8, 128, 128, 3), batch_size=1)
    endpoints, states = network(inputs)

    self.assertAllEqual(endpoints['stem'].shape, [1, 8, 64, 64, 8])
    self.assertAllEqual(endpoints['block0_layer0'].shape, [1, 8, 32, 32, 8])
    self.assertAllEqual(endpoints['block1_layer0'].shape, [1, 8, 16, 16, 32])
    self.assertAllEqual(endpoints['block2_layer0'].shape, [1, 8, 8, 8, 56])
    self.assertAllEqual(endpoints['block3_layer0'].shape, [1, 8, 8, 8, 56])
    self.assertAllEqual(endpoints['block4_layer0'].shape, [1, 8, 4, 4, 104])
    self.assertAllEqual(endpoints['head'].shape, [1, 1, 1, 1, 480])

    self.assertNotEmpty(states)

  def test_network_with_states(self):
    """Test creation of MoViNet family models with states."""
    tf_keras.backend.set_image_data_format('channels_last')

    backbone = movinet.Movinet(
        model_id='a0',
        causal=True,
        use_external_states=True,
    )
    inputs = tf.ones([1, 8, 128, 128, 3])

    init_states = backbone.init_states(tf.shape(inputs))
    endpoints, new_states = backbone({**init_states, 'image': inputs})

    self.assertAllEqual(endpoints['stem'].shape, [1, 8, 64, 64, 8])
    self.assertAllEqual(endpoints['block0_layer0'].shape, [1, 8, 32, 32, 8])
    self.assertAllEqual(endpoints['block1_layer0'].shape, [1, 8, 16, 16, 32])
    self.assertAllEqual(endpoints['block2_layer0'].shape, [1, 8, 8, 8, 56])
    self.assertAllEqual(endpoints['block3_layer0'].shape, [1, 8, 8, 8, 56])
    self.assertAllEqual(endpoints['block4_layer0'].shape, [1, 8, 4, 4, 104])
    self.assertAllEqual(endpoints['head'].shape, [1, 1, 1, 1, 480])

    self.assertNotEmpty(init_states)
    self.assertNotEmpty(new_states)

  def test_movinet_stream(self):
    """Test if the backbone can be run in streaming mode."""
    tf_keras.backend.set_image_data_format('channels_last')

    backbone = movinet.Movinet(
        model_id='a0',
        causal=True,
        use_external_states=True,
    )
    inputs = tf.ones([1, 5, 128, 128, 3])

    init_states = backbone.init_states(tf.shape(inputs))
    expected_endpoints, _ = backbone({**init_states, 'image': inputs})

    frames = tf.split(inputs, inputs.shape[1], axis=1)

    states = init_states
    for frame in frames:
      output, states = backbone({**states, 'image': frame})
    predicted_endpoints = output

    predicted = predicted_endpoints['head']

    # The expected final output is simply the mean across frames
    expected = expected_endpoints['head']
    expected = tf.reduce_mean(expected, 1, keepdims=True)

    self.assertEqual(predicted.shape, expected.shape)
    self.assertAllClose(predicted, expected, 1e-5, 1e-5)

  def test_movinet_stream_nse(self):
    """Test if the backbone can be run in streaming mode w/o SE layer."""
    tf_keras.backend.set_image_data_format('channels_last')

    backbone = movinet.Movinet(
        model_id='a0',
        causal=True,
        use_external_states=True,
        se_type='none',
    )
    inputs = tf.ones([1, 5, 128, 128, 3])

    init_states = backbone.init_states(tf.shape(inputs))
    expected_endpoints, _ = backbone({**init_states, 'image': inputs})

    frames = tf.split(inputs, inputs.shape[1], axis=1)

    states = init_states
    for frame in frames:
      output, states = backbone({**states, 'image': frame})
    predicted_endpoints = output

    predicted = predicted_endpoints['head']

    # The expected final output is simply the mean across frames
    expected = expected_endpoints['head']
    expected = tf.reduce_mean(expected, 1, keepdims=True)

    self.assertEqual(predicted.shape, expected.shape)
    self.assertAllClose(predicted, expected, 1e-5, 1e-5)

    # Check contents in the states dictionary.
    state_keys = list(init_states.keys())
    self.assertIn('state_head_pool_buffer', state_keys)
    self.assertIn('state_head_pool_frame_count', state_keys)
    state_keys.remove('state_head_pool_buffer')
    state_keys.remove('state_head_pool_frame_count')
    # From now on, there are only 'stream_buffer' for the convolutions.
    for state_key in state_keys:
      self.assertIn(
          'stream_buffer', state_key,
          msg=f'Expecting stream_buffer only, found {state_key}')

  def test_movinet_2plus1d_stream(self):
    tf_keras.backend.set_image_data_format('channels_last')

    backbone = movinet.Movinet(
        model_id='a0',
        causal=True,
        conv_type='2plus1d',
        use_external_states=True,
    )
    inputs = tf.ones([1, 5, 128, 128, 3])

    init_states = backbone.init_states(tf.shape(inputs))
    expected_endpoints, _ = backbone({**init_states, 'image': inputs})

    frames = tf.split(inputs, inputs.shape[1], axis=1)

    states = init_states
    for frame in frames:
      output, states = backbone({**states, 'image': frame})
    predicted_endpoints = output

    predicted = predicted_endpoints['head']

    # The expected final output is simply the mean across frames
    expected = expected_endpoints['head']
    expected = tf.reduce_mean(expected, 1, keepdims=True)

    self.assertEqual(predicted.shape, expected.shape)
    self.assertAllClose(predicted, expected, 1e-5, 1e-5)

  def test_movinet_3d_2plus1d_stream(self):
    tf_keras.backend.set_image_data_format('channels_last')

    backbone = movinet.Movinet(
        model_id='a0',
        causal=True,
        conv_type='3d_2plus1d',
        use_external_states=True,
    )
    inputs = tf.ones([1, 5, 128, 128, 3])

    init_states = backbone.init_states(tf.shape(inputs))
    expected_endpoints, _ = backbone({**init_states, 'image': inputs})

    frames = tf.split(inputs, inputs.shape[1], axis=1)

    states = init_states
    for frame in frames:
      output, states = backbone({**states, 'image': frame})
    predicted_endpoints = output

    predicted = predicted_endpoints['head']

    # The expected final output is simply the mean across frames
    expected = expected_endpoints['head']
    expected = tf.reduce_mean(expected, 1, keepdims=True)

    self.assertEqual(predicted.shape, expected.shape)
    self.assertAllClose(predicted, expected, 1e-5, 1e-5)

  def test_serialize_deserialize(self):
    # Create a network object that sets all of its config options.
    kwargs = dict(
        model_id='a0',
        causal=True,
        use_positional_encoding=True,
        use_external_states=True,
    )
    network = movinet.Movinet(**kwargs)

    # Create another network object from the first object's config.
    new_network = movinet.Movinet.from_config(network.get_config())

    # Validate that the config can be forced to JSON.
    _ = new_network.to_json()

    # If the serialization was successful, the new config should match the old.
    self.assertAllEqual(network.get_config(), new_network.get_config())


if __name__ == '__main__':
  tf.test.main()