/**
 * @license
 * Copyright 2020 Google LLC. 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.
 * =============================================================================
 */

import {ENGINE} from '../engine';
import {LeakyRelu, LeakyReluAttrs, LeakyReluInputs} from '../kernel_names';
import {NamedAttrMap} from '../kernel_registry';
import {Tensor} from '../tensor';
import {NamedTensorMap} from '../tensor_types';
import {convertToTensor} from '../tensor_util_env';
import {TensorLike} from '../types';

import {op} from './operation';

/**
 * Computes leaky rectified linear element-wise.
 *
 * See
 * [http://web.stanford.edu/~awni/papers/relu_hybrid_icml2013_final.pdf](
 *     http://web.stanford.edu/~awni/papers/relu_hybrid_icml2013_final.pdf)
 *
 * ```js
 * const x = tf.tensor1d([-1, 2, -3, 4]);
 *
 * x.leakyRelu(0.1).print();  // or tf.leakyRelu(x, 0.1)
 * ```
 * @param x The input tensor.
 * @param alpha The scaling factor for negative values, defaults to 0.2.
 *
 * @doc {heading: 'Operations', subheading: 'Basic math'}
 */
function leakyRelu_<T extends Tensor>(x: T|TensorLike, alpha = 0.2): T {
  const $x = convertToTensor(x, 'x', 'leakyRelu');

  const inputs: LeakyReluInputs = {x: $x};
  const attrs: LeakyReluAttrs = {alpha};

  return ENGINE.runKernel(
      LeakyRelu, inputs as {} as NamedTensorMap, attrs as {} as NamedAttrMap);
}

export const leakyRelu = op({leakyRelu_});