Slice.hpp

/********************************************************************************
 * Copyright (c) 2023 CEA-List
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 ********************************************************************************/

#ifndef AIDGE_CORE_OPERATOR_SLICE_H_
#define AIDGE_CORE_OPERATOR_SLICE_H_

#include <memory>
#include <vector>

#include "aidge/backend/OperatorImpl.hpp"
#include "aidge/data/Data.hpp"
#include "aidge/data/Tensor.hpp"
#include "aidge/graph/Node.hpp"
#include "aidge/operator/Operator.hpp"
#include "aidge/utils/Registrar.hpp"
#include "aidge/utils/StaticAttributes.hpp"
#include "aidge/utils/Types.h"

namespace Aidge {
enum class SliceAttr { Beginning, SliceDims };

template <DimIdx_t DIM>
class Slice_Op
    : public Operator,
      public Registrable<Slice_Op<DIM>, std::string, std::unique_ptr<OperatorImpl>(const Slice_Op<DIM> &)>,
      public StaticAttributes<SliceAttr, std::size_t, std::array<DimSize_t, DIM>> {
public:
    // FIXME: change accessibility
    std::shared_ptr<Tensor> mInput = std::make_shared<Tensor>();
    const std::shared_ptr<Tensor> mOutput = std::make_shared<Tensor>();

public:
    static constexpr const char *Type = "Slice";

    Slice_Op() = delete;

    using Attributes_ = StaticAttributes<SliceAttr, std::size_t, std::array<DimSize_t, DIM>>;
    template <SliceAttr e>
    using attr = typename Attributes_::template attr<e>;

    Slice_Op(std::size_t beginningPos, std::array<DimSize_t, DIM> sliceDims)
        : Operator(Type),
          Attributes_(attr<SliceAttr::Beginning>(beginningPos),
                      attr<SliceAttr::SliceDims>(sliceDims))
    {
        setDatatype(DataType::Float32);
    }

    /**
     * @brief Copy-constructor. Copy the operator attributes and its output tensor(s), but not its
     * input tensors (the new operator has no input associated).
     * @param op Operator to copy.
     */
    Slice_Op(const Slice_Op &op)
        : Operator(Type),
          Attributes_(op),
          mOutput(std::make_shared<Tensor>(*op.mOutput))
    {
        // cpy-ctor
        setDatatype(op.mOutput->dataType());
        mImpl = op.mImpl ? Registrar<Slice_Op<DIM>>::create(mOutput->getImpl()->backend())(*this)
                         : nullptr;
    }

public:
    /**
     * @brief Clone the operator using its copy-constructor.
     * @see Operator::Slice_Op
     */
    std::shared_ptr<Operator> clone() const override { return std::make_shared<Slice_Op>(*this); }

    void associateInput(const IOIndex_t inputIdx, std::shared_ptr<Data> data) override final {
        assert(inputIdx == 0 && "operator supports only 1 input");
        (void)inputIdx;  // avoid unused warning
        assert(strcmp(data->type(), Tensor::Type) == 0 && "input data must be of Tensor type");
        mInput = std::dynamic_pointer_cast<Tensor>(data);
    }

    void computeOutputDims() override final {
        if (!mInput->empty()) {
            // Check input dimensions is compatible with slice dimensions
            if (mInput->nbDims() != DIM) {
                printf("Error: input and slice dimensions are not the same size.\n");
                exit(-1);
            }
            std::array<DimSize_t, DIM> outputDims;

            // Check that the sliced Tensor is actually part of the input Tensor
            // For a 5*5 tensor ('x') and a 3*3 slice kernel ('o'):
            // xxxxx               xxxxx
            // xxxxx               xxxxx
            // xxooo  --> ok       xxxoo --> out of bound
            // xxooo               xxxoo
            // xxooo               xxxoo
            std::vector<std::size_t> beginningCoords = mInput->getCoord(this->template getAttr<SliceAttr::Beginning>());
            for (std::size_t i = 0; i < DIM; ++i) {
                if (beginningCoords[i] + this->template getAttr<SliceAttr::SliceDims>()[i] >= mInput->dims()[i]) {
                    printf("ROI of Slice operator out of bounds");
                    exit(-1);
                } else {
                    outputDims[i] = this->template getAttr<SliceAttr::SliceDims>()[i];
                }
            }

            mOutput->resize(outputDims);
        }
    }

    bool outputDimsForwarded() const override final { return !(mOutput->empty()); }

    inline Tensor &input(const IOIndex_t /*inputIdx*/) const override final {
        return *(mInput.get());
    }
    inline Tensor &output(const IOIndex_t /*outputIdx*/) const override final {
        return *(mOutput.get());
    }

    inline std::shared_ptr<Tensor> getInput(const IOIndex_t inputIdx) const override final {
        assert((inputIdx == 0) && "Slice Operator has only 1 input");
        (void)inputIdx;  // avoid unused warning
        return mInput;
    }
    inline std::shared_ptr<Tensor> getOutput(const IOIndex_t outputIdx) const override final {
        assert((outputIdx == 0) && "Slice Operator has only 1 output");
        (void)outputIdx;  // avoid unused warning
        return mOutput;
    }

    std::shared_ptr<Data> getRawInput(const IOIndex_t inputIdx) const override final {
        assert(inputIdx == 0 && "operator supports only 1 input");
        (void)inputIdx;  // avoid unused warning
        return std::static_pointer_cast<Data>(mInput);
    }
    std::shared_ptr<Data> getRawOutput(const IOIndex_t outputIdx) const override final {
        assert(outputIdx == 0 && "operator supports only 1 output");
        (void)outputIdx;  // avoid unused warning
        return mOutput;
    }

    void setBackend(const std::string &name) {
        mImpl = Registrar<Slice_Op>::create(name)(*this);
        mOutput->setBackend(name);

        // FIXME: temporary workaround
        mInput->setBackend(name);
    }
    void setDatatype(const DataType &datatype) {
        mOutput->setDatatype(datatype);

        // FIXME: temporary workaround
        mInput->setDatatype(datatype);
    }

    inline IOIndex_t nbInputs() const noexcept override final { return 1; }
    inline IOIndex_t nbDataInputs() const noexcept override final { return 1; }
    inline IOIndex_t nbOutputs() const noexcept override final { return 1; }
};

template <DimIdx_t DIM>
inline std::shared_ptr<Node> Slice(std::size_t beginningPos, std::array<DimSize_t, DIM> sliceDims,
                                   const std::string &name = "") {
    // FIXME: properly handle default w&b initialization in every cases
    return std::make_shared<Node>(std::make_shared<Slice_Op<DIM>>( beginningPos, sliceDims), name);
}

template <DimIdx_t DIM>
inline std::shared_ptr<Node> Slice(std::size_t beginningPos, DimSize_t const (&sliceDims)[DIM], const std::string& name = "") {
  return Slice(beginningPos, to_array(sliceDims), name);
}
}  // namespace Aidge

namespace {
template <>
const char *const EnumStrings<Aidge::SliceAttr>::data[] = { "Beginning", "SliceDims" };
}

#endif /* AIDGE_CORE_OPERATOR_RELU_H_ */