# Copyright 2021 DeepMind Technologies Limited
#
# 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.

"""Shared utilities for various components."""
import tensorflow.compat.v1 as tf


def tf_combine_mask(*masks):
  """Take the intersection of float-valued masks."""
  ret = 1
  for m in masks:
    ret *= m
  return ret


class SeedMaker(object):
  """Return unique seeds."""

  def __init__(self, initial_seed=0):
    self.next_seed = initial_seed

  def __call__(self):
    i = self.next_seed
    self.next_seed += 1
    return i

seed_maker = SeedMaker()


def make_random_seed():
  return tf.random.uniform([2],
                           tf.int32.min,
                           tf.int32.max,
                           tf.int32,
                           seed=seed_maker())