//*****************************************************************************
// Copyright 2017-2019 Intel Corporation
//
// 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.
//*****************************************************************************

#pragma once

#include "ngraph/op/op.hpp"
#include "ngraph/op/util/attr_types.hpp"

namespace ngraph
{
    namespace op
    {
        namespace util
        {
            /// \brief Abstract base class for elementwise binary arithmetic operations, i.e., operations where the same
            ///        scalar binary arithmetic operation is applied to each corresponding pair of elements in the two
            ///        input tensors. Implicit broadcast of input tensors is supported through one of the AutoBroadcast modes
            ///
            /// For example, if the underlying arithmetic operation (determined by the subclass) is \f$\mathit{op}(x,y)\f$, the input tensors
            /// \f$[[x_0,y_0],[z_0,w_0]]\f$ and \f$[[x_1,y_1],[z_1,w_1]]\f$ will be mapped to \f$[[\mathit{op}(x_0,x_1),\mathit{op}(y_0,y_1)],[\mathit{op}(z_0,z_1),\mathit{op}(w_0,w_1)]]\f$.
            ///
            /// ## Inputs
            ///
            /// |        | Type                              | Description                                                              |
            /// | ------ | --------------------------------- | ------------------------------------------------------------------------ |
            /// | `arg0` | \f$N[d_1,\dots,d_n]~(n \geq 0)\f$ | A tensor of any shape. The element type \f$N\f$ may be any numeric type. |
            /// | `arg1` | \f$N[d_1,\dots,d_n]~(n \geq 0)\f$ | A tensor of the same element type as `arg0`.                             |
            /// | `autob`| AutoBroadcastSpec                 | Auto broadcast specification.                                            |
            ///
            /// ## Output
            ///
            /// | Type                   | Description                                                                                                                                                                                            |
            /// | ---------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
            /// | \f$N[d_1,\dots,d_n]\f$ | The tensor \f$T\f$, where \f$T[i_1,\dots,i_n] = \mathit{op}(\texttt{arg0}[i_1,\dots,i_n],\texttt{arg1}[i_1,\dots,i_n])\f$. This will always have the same shape and element type as the input tensors (after auto broadcasting). |
            class BinaryElementwiseArithmetic : public Op
            {
            protected:
                /// \brief Constructs a binary elementwise arithmetic operation.
                BinaryElementwiseArithmetic();

                BinaryElementwiseArithmetic(const std::shared_ptr<Node>& arg0,
                                            const std::shared_ptr<Node>& arg1,
                                            const AutoBroadcastSpec& autob = AutoBroadcastSpec());

                /// \brief Constructs a binary elementwise arithmetic operation.
                ///
                /// \param arg0 Output that produces the first input tensor.
                /// \param arg1 Output that produces the second input tensor.
                BinaryElementwiseArithmetic(const Output<Node>& arg0,
                                            const Output<Node>& arg1,
                                            const AutoBroadcastSpec& autob = AutoBroadcastSpec());

                /// \brief Constructs a binary elementwise arithmetic operation.
                ///
                /// \param arg0 Node that produces the first input tensor.
                /// \param arg1 Node that produces the second input tensor.
                /// \param autob AutoBroadcast mode.
                BinaryElementwiseArithmetic(const std::string& node_type,
                                            const std::shared_ptr<Node>& arg0,
                                            const std::shared_ptr<Node>& arg1,
                                            const AutoBroadcastSpec& autob = AutoBroadcastSpec());

            public:
                void validate_and_infer_types() override;

                const AutoBroadcastSpec& get_autob() const { return m_autob; }
                void set_autob(const AutoBroadcastSpec& autob) { m_autob = autob; }
            private:
                AutoBroadcastSpec m_autob;
            };
        }
    }
}
