// Tencent is pleased to support the open source community by making ncnn available.
//
// Copyright (C) 2019 THL A29 Limited, a Tencent company. All rights reserved.
//
// Licensed under the BSD 3-Clause License (the "License"); you may not use this file except
// in compliance with the License. You may obtain a copy of the License at
//
// https://opensource.org/licenses/BSD-3-Clause
//
// 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.

#include "eltwise_vulkan.h"

#include "layer_shader_type.h"

namespace ncnn {

Eltwise_vulkan::Eltwise_vulkan()
{
    support_vulkan = true;
    support_image_storage = true;

    pipeline_eltwise[0] = 0;
    pipeline_eltwise[1] = 0;
    pipeline_eltwise_pack4[0] = 0;
    pipeline_eltwise_pack4[1] = 0;
    pipeline_eltwise_pack8[0] = 0;
    pipeline_eltwise_pack8[1] = 0;
}

int Eltwise_vulkan::create_pipeline(const Option& opt)
{
    const Mat& shape = top_shapes.empty() ? Mat() : top_shapes[0];

    int elempack = 1;
    if (shape.dims == 1) elempack = opt.use_shader_pack8 && shape.w % 8 == 0 ? 8 : shape.w % 4 == 0 ? 4 : 1;
    if (shape.dims == 2) elempack = opt.use_shader_pack8 && shape.h % 8 == 0 ? 8 : shape.h % 4 == 0 ? 4 : 1;
    if (shape.dims == 3 || shape.dims == 4) elempack = opt.use_shader_pack8 && shape.c % 8 == 0 ? 8 : shape.c % 4 == 0 ? 4 : 1;

    size_t elemsize;
    if (opt.use_fp16_storage)
    {
        elemsize = elempack * 2u;
    }
    else if (opt.use_fp16_packed)
    {
        elemsize = elempack == 1 ? 4u : elempack * 2u;
    }
    else
    {
        elemsize = elempack * 4u;
    }

    Mat shape_packed;
    if (shape.dims == 1) shape_packed = Mat(shape.w / elempack, (void*)0, elemsize, elempack);
    if (shape.dims == 2) shape_packed = Mat(shape.w, shape.h / elempack, (void*)0, elemsize, elempack);
    if (shape.dims == 3 || shape.dims == 4) shape_packed = Mat(shape.w, shape.h, shape.c / elempack, (void*)0, elemsize, elempack);

    std::vector<vk_specialization_type> specializations(2 + 5);
    specializations[0].i = op_type;
    specializations[1].i = coeffs.w == 0 ? 0 : 1;
    specializations[2 + 0].i = shape_packed.dims;
    specializations[2 + 1].i = shape_packed.w;
    specializations[2 + 2].i = shape_packed.h * shape_packed.d;
    specializations[2 + 3].i = shape_packed.c;
    specializations[2 + 4].i = shape_packed.cstep;

    Mat local_size_xyz;
    if (shape_packed.dims == 1)
    {
        local_size_xyz.w = std::min(64, shape_packed.w);
        local_size_xyz.h = 1;
        local_size_xyz.c = 1;
    }
    if (shape_packed.dims == 2)
    {
        local_size_xyz.w = std::min(8, shape_packed.w);
        local_size_xyz.h = std::min(8, shape_packed.h);
        local_size_xyz.c = 1;
    }
    if (shape_packed.dims == 3)
    {
        local_size_xyz.w = std::min(4, shape_packed.w);
        local_size_xyz.h = std::min(4, shape_packed.h);
        local_size_xyz.c = std::min(4, shape_packed.c);
    }
    if (shape_packed.dims == 4)
    {
        local_size_xyz.w = std::min(4, shape_packed.w);
        local_size_xyz.h = std::min(4, shape_packed.h * shape_packed.d);
        local_size_xyz.c = std::min(4, shape_packed.c);
    }

    // pack1
    if (shape.dims == 0 || elempack == 1)
    {
        pipeline_eltwise[0] = new Pipeline(vkdev);
        pipeline_eltwise[0]->set_optimal_local_size_xyz(local_size_xyz);
        pipeline_eltwise[0]->create(LayerShaderType::eltwise, opt, specializations);
        pipeline_eltwise[1] = new Pipeline(vkdev);
        pipeline_eltwise[1]->set_optimal_local_size_xyz(local_size_xyz);
        pipeline_eltwise[1]->create(LayerShaderType::eltwise, opt, specializations);
    }

    // pack4
    if (shape.dims == 0 || elempack == 4)
    {
        pipeline_eltwise_pack4[0] = new Pipeline(vkdev);
        pipeline_eltwise_pack4[0]->set_optimal_local_size_xyz(local_size_xyz);
        pipeline_eltwise_pack4[0]->create(LayerShaderType::eltwise_pack4, opt, specializations);
        pipeline_eltwise_pack4[1] = new Pipeline(vkdev);
        pipeline_eltwise_pack4[1]->set_optimal_local_size_xyz(local_size_xyz);
        pipeline_eltwise_pack4[1]->create(LayerShaderType::eltwise_pack4, opt, specializations);
    }

    // pack8
    if ((opt.use_shader_pack8 && shape.dims == 0) || elempack == 8)
    {
        pipeline_eltwise_pack8[0] = new Pipeline(vkdev);
        pipeline_eltwise_pack8[0]->set_optimal_local_size_xyz(local_size_xyz);
        pipeline_eltwise_pack8[0]->create(LayerShaderType::eltwise_pack8, opt, specializations);
        pipeline_eltwise_pack8[1] = new Pipeline(vkdev);
        pipeline_eltwise_pack8[1]->set_optimal_local_size_xyz(local_size_xyz);
        pipeline_eltwise_pack8[1]->create(LayerShaderType::eltwise_pack8, opt, specializations);
    }

    return 0;
}

int Eltwise_vulkan::destroy_pipeline(const Option& /*opt*/)
{
    delete pipeline_eltwise[0];
    delete pipeline_eltwise[1];
    pipeline_eltwise[0] = 0;
    pipeline_eltwise[1] = 0;

    delete pipeline_eltwise_pack4[0];
    delete pipeline_eltwise_pack4[1];
    pipeline_eltwise_pack4[0] = 0;
    pipeline_eltwise_pack4[1] = 0;

    delete pipeline_eltwise_pack8[0];
    delete pipeline_eltwise_pack8[1];
    pipeline_eltwise_pack8[0] = 0;
    pipeline_eltwise_pack8[1] = 0;

    return 0;
}

int Eltwise_vulkan::forward(const std::vector<VkMat>& bottom_blobs, std::vector<VkMat>& top_blobs, VkCompute& cmd, const Option& opt) const
{
    const VkMat& bottom_blob = bottom_blobs[0];
    const VkMat& bottom_blob1 = bottom_blobs[1];

    int elempack = bottom_blob.elempack;

    VkMat& top_blob = top_blobs[0];
    top_blob.create_like(bottom_blob, opt.blob_vkallocator);
    if (top_blob.empty())
        return -100;

    std::vector<VkMat> bindings(3);
    bindings[0] = bottom_blob;
    bindings[1] = bottom_blob1;
    bindings[2] = top_blob;

    std::vector<vk_constant_type> constants(5 + 2);
    constants[0].i = top_blob.dims;
    constants[1].i = top_blob.w;
    constants[2].i = top_blob.h * top_blob.d;
    constants[3].i = top_blob.c;
    constants[4].i = top_blob.cstep;
    constants[5].f = coeffs.w == 0 ? 1.f : coeffs[0];
    constants[6].f = coeffs.w == 0 ? 1.f : coeffs[1];

    const Pipeline* pipeline = elempack == 8 ? pipeline_eltwise_pack8[1]
                               : elempack == 4 ? pipeline_eltwise_pack4[1]
                               : pipeline_eltwise[1];

    cmd.record_pipeline(pipeline, bindings, constants, top_blob);

    for (size_t b = 2; b < bottom_blobs.size(); b++)
    {
        std::vector<VkMat> bindings(3);
        bindings[0] = top_blob;
        bindings[1] = bottom_blobs[b];
        bindings[2] = top_blob; // TODO use separated pipeline ?

        std::vector<vk_constant_type> constants(5 + 2);
        constants[0].i = top_blob.dims;
        constants[1].i = top_blob.w;
        constants[2].i = top_blob.h * top_blob.d;
        constants[3].i = top_blob.c;
        constants[4].i = top_blob.cstep;
        constants[5].f = 1.f;
        constants[6].f = coeffs.w == 0 ? 1 : coeffs[b];

        const Pipeline* pipeline = elempack == 8 ? pipeline_eltwise_pack8[b % 2]
                                   : elempack == 4 ? pipeline_eltwise_pack4[b % 2]
                                   : pipeline_eltwise[b % 2];

        cmd.record_pipeline(pipeline, bindings, constants, top_blob);
    }

    return 0;
}

int Eltwise_vulkan::forward(const std::vector<VkImageMat>& bottom_blobs, std::vector<VkImageMat>& top_blobs, VkCompute& cmd, const Option& opt) const
{
    const VkImageMat& bottom_blob = bottom_blobs[0];
    const VkImageMat& bottom_blob1 = bottom_blobs[1];

    int elempack = bottom_blob.elempack;

    VkImageMat& top_blob = top_blobs[0];
    top_blob.create_like(bottom_blob, opt.blob_vkallocator);
    if (top_blob.empty())
        return -100;

    std::vector<VkImageMat> bindings(3);
    bindings[0] = bottom_blob;
    bindings[1] = bottom_blob1;
    bindings[2] = top_blob;

    std::vector<vk_constant_type> constants(5 + 2);
    constants[0].i = top_blob.dims;
    constants[1].i = top_blob.w;
    constants[2].i = top_blob.h * top_blob.d;
    constants[3].i = top_blob.c;
    constants[4].i = 0; //top_blob.cstep;
    constants[5].f = coeffs.w == 0 ? 1.f : coeffs[0];
    constants[6].f = coeffs.w == 0 ? 1.f : coeffs[1];

    const Pipeline* pipeline = elempack == 8 ? pipeline_eltwise_pack8[1]
                               : elempack == 4 ? pipeline_eltwise_pack4[1]
                               : pipeline_eltwise[1];

    cmd.record_pipeline(pipeline, bindings, constants, top_blob);

    for (size_t b = 2; b < bottom_blobs.size(); b++)
    {
        std::vector<VkImageMat> bindings(3);
        bindings[0] = top_blob;
        bindings[1] = bottom_blobs[b];
        bindings[2] = top_blob; // TODO use separated pipeline ?

        std::vector<vk_constant_type> constants(5 + 2);
        constants[0].i = top_blob.dims;
        constants[1].i = top_blob.w;
        constants[2].i = top_blob.h * top_blob.d;
        constants[3].i = top_blob.c;
        constants[4].i = 0; //top_blob.cstep;
        constants[5].f = 1.f;
        constants[6].f = coeffs.w == 0 ? 1 : coeffs[b];

        const Pipeline* pipeline = elempack == 8 ? pipeline_eltwise_pack8[b % 2]
                                   : elempack == 4 ? pipeline_eltwise_pack4[b % 2]
                                   : pipeline_eltwise[b % 2];

        cmd.record_pipeline(pipeline, bindings, constants, top_blob);
    }

    return 0;
}

} // namespace ncnn