/*
 * Copyright (c) 2019-2020 ARM Limited.
 *
 * SPDX-License-Identifier: MIT
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
#include "arm_compute/core/NEON/kernels/NEHeightConcatenateLayerKernel.h"

#include "arm_compute/core/Error.h"
#include "arm_compute/core/Helpers.h"
#include "arm_compute/core/IAccessWindow.h"
#include "arm_compute/core/ITensor.h"
#include "arm_compute/core/NEON/NEAsymm.h"
#include "arm_compute/core/NEON/wrapper/wrapper.h"
#include "arm_compute/core/TensorInfo.h"
#include "arm_compute/core/Utils.h"
#include "arm_compute/core/Validate.h"
#include "arm_compute/core/Window.h"

#include <cstdint>

namespace arm_compute
{
namespace
{
Status validate_arguments(const ITensorInfo *input, unsigned int height_offset, const ITensorInfo *output)
{
    ARM_COMPUTE_RETURN_ERROR_ON_NULLPTR(input, output);
    // Note: ARM_COMPUTE_RETURN_ERROR_ON_CPU_F16_UNSUPPORTED(input) is not needed here as this kernel doesn't use NEON FP16 instructions.
    ARM_COMPUTE_RETURN_ERROR_ON(input->data_type() == DataType::UNKNOWN);
    ARM_COMPUTE_RETURN_ERROR_ON_MISMATCHING_DATA_TYPES(input, output);
    ARM_COMPUTE_RETURN_ERROR_ON(input->dimension(Window::DimX) != output->dimension(Window::DimX));
    ARM_COMPUTE_RETURN_ERROR_ON(input->dimension(Window::DimY) + height_offset > output->dimension(Window::DimY));
    for(size_t i = 2; i < Coordinates::num_max_dimensions; ++i)
    {
        ARM_COMPUTE_RETURN_ERROR_ON(input->dimension(i) != output->dimension(i));
    }

    return Status{};
}
} // namespace

NEHeightConcatenateLayerKernel::NEHeightConcatenateLayerKernel()
    : _input(nullptr), _output(nullptr), _height_offset(0)
{
}

void NEHeightConcatenateLayerKernel::configure(const ITensor *input, unsigned int height_offset, ITensor *output)
{
    ARM_COMPUTE_ERROR_ON_NULLPTR(input, output);
    ARM_COMPUTE_ERROR_THROW_ON(validate_arguments(input->info(), height_offset, output->info()));

    _input         = input;
    _output        = output;
    _height_offset = height_offset;

    // Configure kernel window
    Window      win = calculate_max_window(*output->info(), Steps());
    Coordinates coord;
    coord.set_num_dimensions(output->info()->num_dimensions());
    output->info()->set_valid_region(ValidRegion(coord, output->info()->tensor_shape()));
    INEKernel::configure(win);
}

Status NEHeightConcatenateLayerKernel::validate(const ITensorInfo *input, unsigned int height_offset, const ITensorInfo *output)
{
    ARM_COMPUTE_RETURN_ON_ERROR(validate_arguments(input, height_offset, output));
    return Status{};
}

void NEHeightConcatenateLayerKernel::run(const Window &window, const ThreadInfo &info)
{
    ARM_COMPUTE_UNUSED(info);
    ARM_COMPUTE_ERROR_ON_UNCONFIGURED_KERNEL(this);
    ARM_COMPUTE_ERROR_ON_INVALID_SUBWINDOW(INEKernel::window(), window);

    // Offset output pointer to the correct position
    uint8_t *output_ptr = _output->buffer() + _output->info()->offset_first_element_in_bytes() + _height_offset * _output->info()->strides_in_bytes()[Window::DimY];

    const auto window_start_x = static_cast<int>(window.x().start());
    const auto window_end_x   = static_cast<int>(window.x().end()) * static_cast<int>(_output->info()->element_size()); 
    const int window_step_x = 16;

    Window win{ window };
    win.set(Window::DimX, Window::Dimension(0, 1, 1));
    win.set(Window::DimY, Window::Dimension(0, _input->info()->tensor_shape().y(), 1));

    // Create iterators
    Iterator input(_input, win);
    Iterator output(_output, win);

    const DataType                 dt           = _input->info()->data_type();
    const UniformQuantizationInfo &input_qinfo  = _input->info()->quantization_info().uniform();
    const UniformQuantizationInfo &output_qinfo = _output->info()->quantization_info().uniform();
    if(dt == DataType::QASYMM8 && input_qinfo != output_qinfo)
    {
        execute_window_loop(win, [&](const Coordinates &)
        {
            int x = window_start_x;
            for(; x <= (window_end_x - window_step_x); x += window_step_x)
            {
                vst1q_u8(output_ptr + output.offset() + x, vquantize(vdequantize(vld1q_u8(input.ptr() + x), input_qinfo), output_qinfo));
            }

            // Compute left-over elements
            for(; x < window_end_x; ++x)
            {
                *(output_ptr + output.offset() + x) = quantize_qasymm8(dequantize_qasymm8(*(input.ptr() + x), input_qinfo), output_qinfo);
            }

        },
        input, output);
    }
    else if(dt == DataType::QASYMM8_SIGNED && input_qinfo != output_qinfo)
    {
        execute_window_loop(win, [&](const Coordinates &)
        {
            int x = window_start_x;
            for(; x <= (window_end_x - window_step_x); x += window_step_x)
            {
                vst1q_s8(reinterpret_cast<int8_t *>(output_ptr + output.offset() + x),
                         vquantize_signed(vdequantize(vld1q_s8(reinterpret_cast<int8_t *>(input.ptr()) + x), input_qinfo), output_qinfo));
            }

            // Compute left-over elements
            for(; x < window_end_x; ++x)
            {
                *(output_ptr + output.offset() + x) = quantize_qasymm8_signed(dequantize_qasymm8_signed(*(input.ptr() + x), input_qinfo), output_qinfo);
            }
        },
        input, output);
    }
    else
    {
        execute_window_loop(win, [&](const Coordinates &)
        {
            const auto in_ptr  = input.ptr();
            const auto out_ptr = output_ptr + output.offset();

            int x = window_start_x;
            for(; x <= (window_end_x - window_step_x); x += window_step_x)
            {
                wrapper::vstore(out_ptr + x, wrapper::vloadq(in_ptr + x));
            }

            // Compute left-over elements
            for(; x < window_end_x; ++x)
            {
                *(out_ptr + x) = *(in_ptr + x);
            }
        },
        input, output);
    }
}
} // namespace arm_compute