//*****************************************************************************
// 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 <utility>

#include "ngraph/op/op.hpp"

namespace ngraph
{
    namespace op
    {
        /// \brief Generalized dot product operation, including scalar-tensor product, matrix-vector
        ///        product, and matrix multiplication.
        class Dot : public Op
        {
        public:
            NGRAPH_API
            static const std::string type_name;
            const std::string& description() const override { return type_name; }
            /// \brief Constructs a dot product operation.
            Dot() = default;
            /// \brief Constructs a dot product operation.
            ///
            /// \param arg0 The node producing the first argument.
            /// \param arg1 The node producing the second argument.
            /// \param reduction_axes_count The number of axes to dot.
            Dot(const Output<Node>& arg0,
                const Output<Node>& arg1,
                size_t reduction_axes_count,
                bool has_reduction_axes_count = true);

            /// \brief Constructs a dot product operation with default dot-axis selection depending
            ///        on the inputs.
            ///
            /// If `arg0` or `arg1` is a scalar, there are no dot-axes. Else, there is one dot-axis.
            ///
            /// (Note that in particular, this results in scalar-tensor products where one or the
            /// other argument is a scalar, a matrix-vector products where `arg0` is a matrix and
            /// `arg1` is a vector, and a matrix multiplication where `arg0` and `arg1` are both
            /// matrices.)
            ///
            /// \param arg0 The node producing the first argument.
            /// \param arg1 The node producing the second argument.
            Dot(const Output<Node>& arg0, const Output<Node>& arg1);

            void validate_and_infer_types() override;

            size_t get_reduction_axes_count() const { return m_reduction_axes_count; }
            void set_reduction_axes_count(size_t reduction_axes_count)
            {
                m_reduction_axes_count = reduction_axes_count;
            }
            bool get_has_reduction_axes_count() const { return m_has_reduction_axes_count; }
            void set_has_reduction_axes_count(bool has_reduction_axes_count)
            {
                m_has_reduction_axes_count = has_reduction_axes_count;
            }
            virtual std::shared_ptr<Node>
                copy_with_new_args(const NodeVector& new_args) const override
            {
                check_new_args_count(this, new_args);
                return std::make_shared<Dot>(
                    new_args.at(0), new_args.at(1), m_reduction_axes_count);
            }

        protected:
            size_t m_reduction_axes_count;
            bool m_has_reduction_axes_count;

            virtual void generate_adjoints(autodiff::Adjoints& adjoints,
                                           const NodeVector& deltas) override;
        };
    }
}
