# Copyright 2019 DeepMind Technologies Limited. 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.
# ==============================================================================
"""Tests that types are preserved by the `update` calls when jax_enbable_x64."""

from absl.testing import absltest
from absl.testing import parameterized

import chex
import jax
from jax import config
import jax.numpy as jnp

from optax._src import alias
from optax._src import base
from optax._src import clipping
from optax._src import transform
from optax._src import update


ALL_MODULES = [
    ('identity', base.identity, {}),
    ('clip', clipping.clip, dict(max_delta=1.0)),
    ('clip_by_global_norm', clipping.clip_by_global_norm, dict(max_norm=1.0)),
    ('trace', transform.trace, dict(decay=0.5, nesterov=False)),
    ('trace_with_nesterov', transform.trace, dict(decay=0.5, nesterov=True)),
    ('scale_by_rss', transform.scale_by_rss, {}),
    ('scale_by_rms', transform.scale_by_rms, {}),
    ('scale_by_stddev', transform.scale_by_stddev, {}),
    ('adam', transform.scale_by_adam, {}),
    ('scale', transform.scale, dict(step_size=3.0)),
    ('add_decayed_weights', transform.add_decayed_weights,
     dict(weight_decay=0.1)),
    ('scale_by_schedule', transform.scale_by_schedule,
     dict(step_size_fn=lambda x: x * 0.1)),
    ('scale_by_trust_ratio', transform.scale_by_trust_ratio, {}),
    ('add_noise', transform.add_noise, dict(eta=1.0, gamma=0.1, seed=42)),
    ('apply_every_k', transform.apply_every, {}),
    ('adagrad', alias.adagrad, dict(learning_rate=0.1)),
    ('adam', alias.adam, dict(learning_rate=0.1)),
    ('adamw', alias.adamw, dict(learning_rate=0.1)),
    ('fromage', alias.fromage, dict(learning_rate=0.1)),
    ('lamb', alias.lamb, dict(learning_rate=0.1)),
    ('noisy_sgd', alias.noisy_sgd, dict(learning_rate=0.1)),
    ('rmsprop', alias.rmsprop, dict(learning_rate=0.1)),
    ('sgd', alias.sgd, dict(learning_rate=0.1)),
]


class Float64Test(parameterized.TestCase):

  def _assert_dtype_equals(self, tree1, tree2):
    tree1_types = jax.tree_util.tree_map(lambda t: t.dtype, tree1)
    tree2_types = jax.tree_util.tree_map(lambda t: t.dtype, tree2)
    self.assertEqual(tree1_types, tree2_types)

  @chex.all_variants
  @parameterized.named_parameters(ALL_MODULES)
  def test_mixed_dtype_input_outputs(self, transform_constr, transform_kwargs):
    initial_params = (
        jnp.array([1., 2.], dtype=jnp.float32),
        jnp.array([3., 4.], dtype=jnp.float64))
    updates = (
        jnp.array([10., 21.], dtype=jnp.float32),
        jnp.array([33., 42.], dtype=jnp.float64))
    scaler = transform_constr(**transform_kwargs)
    init_fn = self.variant(scaler.init)
    update_fn = self.variant(scaler.update)

    initial_state = init_fn(initial_params)
    updates, new_state = update_fn(
        updates, initial_state, params=initial_params)
    new_params = update.apply_updates(initial_params, updates)

    self._assert_dtype_equals(initial_state, new_state)
    self._assert_dtype_equals(initial_params, new_params)


if __name__ == '__main__':
  config.update('jax_enable_x64', True)
  absltest.main()