/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * 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.
 */

#ifndef FRAMEWORKS_ML_NN_SVDF_H
#define FRAMEWORKS_ML_NN_SVDF_H

#include "HalOperation.h"
#include "tensorflow/lite/kernels/internal/tensor_utils.h"

#include <algorithm>
#include <cmath>

namespace android {
namespace nn {

struct SVDFParams {
    int rank_;
    TfLiteFusedActivation activation_;
};

struct RunTimeOperandInfo;
struct Shape;

class SVDF {
   public:
    SVDF(const Operation& operation, std::vector<RunTimeOperandInfo>& operands);

    static bool Prepare(const Operation& operation, std::vector<RunTimeOperandInfo>& operands,
                        Shape* stateShape, Shape* outputShape);
    bool Eval();

    static constexpr int kInputTensor = 0;
    static constexpr int kWeightsFeatureTensor = 1;
    static constexpr int kWeightsTimeTensor = 2;
    static constexpr int kBiasTensor = 3;  // Optional
    static constexpr int kStateInTensor = 4;
    static constexpr int kRankParam = 5;
    static constexpr int kActivationParam = 6;

    static constexpr int kStateOutTensor = 0;
    static constexpr int kOutputTensor = 1;

   private:
    void EvalFloat32(const float* inputData, const float* inputStateData, const float* biasData,
                     const float* weightsFeatureData, const float* weightsTimeData,
                     float* outputData, float* outputStateData);

    SVDFParams params_;

    const RunTimeOperandInfo* input_;
    const RunTimeOperandInfo* weights_feature_;
    const RunTimeOperandInfo* weights_time_;
    const RunTimeOperandInfo* bias_;
    const RunTimeOperandInfo* state_in_;

    RunTimeOperandInfo* state_out_;
    RunTimeOperandInfo* output_;
};

}  // namespace nn
}  // namespace android

#endif