/*
* Copyright 2016 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/

#include "vk/GrVkPipelineStateBuilder.h"

#include "GrShaderCaps.h"
#include "vk/GrVkDescriptorSetManager.h"
#include "vk/GrVkGpu.h"
#include "vk/GrVkRenderPass.h"


GrVkPipelineState* GrVkPipelineStateBuilder::CreatePipelineState(
                                                               GrVkGpu* gpu,
                                                               const GrPipeline& pipeline,
                                                               const GrStencilSettings& stencil,
                                                               const GrPrimitiveProcessor& primProc,
                                                               GrPrimitiveType primitiveType,
                                                               GrVkPipelineState::Desc* desc,
                                                               const GrVkRenderPass& renderPass) {
    // create a builder.  This will be handed off to effects so they can use it to add
    // uniforms, varyings, textures, etc
    GrVkPipelineStateBuilder builder(gpu, pipeline, primProc, desc);

    if (!builder.emitAndInstallProcs()) {
        builder.cleanupFragmentProcessors();
        return nullptr;
    }

    return builder.finalize(stencil, primitiveType, renderPass, desc);
}

GrVkPipelineStateBuilder::GrVkPipelineStateBuilder(GrVkGpu* gpu,
                                                   const GrPipeline& pipeline,
                                                   const GrPrimitiveProcessor& primProc,
                                                   GrProgramDesc* desc)
    : INHERITED(pipeline, primProc, desc)
    , fGpu(gpu)
    , fVaryingHandler(this)
    , fUniformHandler(this) {
}

const GrCaps* GrVkPipelineStateBuilder::caps() const {
    return fGpu->caps();
}

void GrVkPipelineStateBuilder::finalizeFragmentOutputColor(GrShaderVar& outputColor) {
    outputColor.addLayoutQualifier("location = 0, index = 0");
}

void GrVkPipelineStateBuilder::finalizeFragmentSecondaryColor(GrShaderVar& outputColor) {
    outputColor.addLayoutQualifier("location = 0, index = 1");
}

bool GrVkPipelineStateBuilder::createVkShaderModule(VkShaderStageFlagBits stage,
                                                    const GrGLSLShaderBuilder& builder,
                                                    VkShaderModule* shaderModule,
                                                    VkPipelineShaderStageCreateInfo* stageInfo,
                                                    const SkSL::Program::Settings& settings,
                                                    GrVkPipelineState::Desc* desc) {
    SkString shaderString;
    for (int i = 0; i < builder.fCompilerStrings.count(); ++i) {
        if (builder.fCompilerStrings[i]) {
            shaderString.append(builder.fCompilerStrings[i]);
            shaderString.append("\n");
        }
    }

    SkSL::Program::Inputs inputs;
    bool result = GrCompileVkShaderModule(fGpu, shaderString.c_str(), stage, shaderModule,
                                          stageInfo, settings, &inputs);
    if (!result) {
        return false;
    }
    if (inputs.fRTHeight) {
        this->addRTHeightUniform(SKSL_RTHEIGHT_NAME);
    }
    if (inputs.fFlipY) {
        desc->setSurfaceOriginKey(GrGLSLFragmentShaderBuilder::KeyForSurfaceOrigin(
                                                     this->pipeline().proxy()->origin()));
        desc->finalize();
    }
    return result;
}

GrVkPipelineState* GrVkPipelineStateBuilder::finalize(const GrStencilSettings& stencil,
                                                      GrPrimitiveType primitiveType,
                                                      const GrVkRenderPass& renderPass,
                                                      GrVkPipelineState::Desc* desc) {
    VkDescriptorSetLayout dsLayout[3];
    VkPipelineLayout pipelineLayout;
    VkShaderModule vertShaderModule = VK_NULL_HANDLE;
    VkShaderModule geomShaderModule = VK_NULL_HANDLE;
    VkShaderModule fragShaderModule = VK_NULL_HANDLE;

    GrVkResourceProvider& resourceProvider = fGpu->resourceProvider();
    // These layouts are not owned by the PipelineStateBuilder and thus should not be destroyed
    dsLayout[GrVkUniformHandler::kUniformBufferDescSet] = resourceProvider.getUniformDSLayout();

    GrVkDescriptorSetManager::Handle samplerDSHandle;
    resourceProvider.getSamplerDescriptorSetHandle(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER,
                                                   fUniformHandler, &samplerDSHandle);
    dsLayout[GrVkUniformHandler::kSamplerDescSet] =
            resourceProvider.getSamplerDSLayout(samplerDSHandle);

    GrVkDescriptorSetManager::Handle texelBufferDSHandle;
    resourceProvider.getSamplerDescriptorSetHandle(VK_DESCRIPTOR_TYPE_UNIFORM_TEXEL_BUFFER,
                                                   fUniformHandler, &texelBufferDSHandle);
    dsLayout[GrVkUniformHandler::kTexelBufferDescSet] =
            resourceProvider.getSamplerDSLayout(texelBufferDSHandle);

    // Create the VkPipelineLayout
    VkPipelineLayoutCreateInfo layoutCreateInfo;
    memset(&layoutCreateInfo, 0, sizeof(VkPipelineLayoutCreateFlags));
    layoutCreateInfo.sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO;
    layoutCreateInfo.pNext = 0;
    layoutCreateInfo.flags = 0;
    layoutCreateInfo.setLayoutCount = 3;
    layoutCreateInfo.pSetLayouts = dsLayout;
    layoutCreateInfo.pushConstantRangeCount = 0;
    layoutCreateInfo.pPushConstantRanges = nullptr;

    GR_VK_CALL_ERRCHECK(fGpu->vkInterface(), CreatePipelineLayout(fGpu->device(),
                                                                  &layoutCreateInfo,
                                                                  nullptr,
                                                                  &pipelineLayout));

    // We need to enable the following extensions so that the compiler can correctly make spir-v
    // from our glsl shaders.
    fVS.extensions().appendf("#extension GL_ARB_separate_shader_objects : enable\n");
    fFS.extensions().appendf("#extension GL_ARB_separate_shader_objects : enable\n");
    fVS.extensions().appendf("#extension GL_ARB_shading_language_420pack : enable\n");
    fFS.extensions().appendf("#extension GL_ARB_shading_language_420pack : enable\n");

    this->finalizeShaders();

    VkPipelineShaderStageCreateInfo shaderStageInfo[3];
    SkSL::Program::Settings settings;
    settings.fCaps = this->caps()->shaderCaps();
    settings.fFlipY = this->pipeline().proxy()->origin() != kTopLeft_GrSurfaceOrigin;
    SkAssertResult(this->createVkShaderModule(VK_SHADER_STAGE_VERTEX_BIT,
                                              fVS,
                                              &vertShaderModule,
                                              &shaderStageInfo[0],
                                              settings,
                                              desc));

    SkAssertResult(this->createVkShaderModule(VK_SHADER_STAGE_FRAGMENT_BIT,
                                              fFS,
                                              &fragShaderModule,
                                              &shaderStageInfo[1],
                                              settings,
                                              desc));

    int numShaderStages = 2; // We always have at least vertex and fragment stages.
    if (this->primitiveProcessor().willUseGeoShader()) {
        SkAssertResult(this->createVkShaderModule(VK_SHADER_STAGE_GEOMETRY_BIT,
                                                  fGS,
                                                  &geomShaderModule,
                                                  &shaderStageInfo[2],
                                                  settings,
                                                  desc));
        ++numShaderStages;
    }

    GrVkPipeline* pipeline = resourceProvider.createPipeline(fPipeline,
                                                             stencil,
                                                             fPrimProc,
                                                             shaderStageInfo,
                                                             numShaderStages,
                                                             primitiveType,
                                                             renderPass,
                                                             pipelineLayout);
    GR_VK_CALL(fGpu->vkInterface(), DestroyShaderModule(fGpu->device(), vertShaderModule,
                                                        nullptr));
    GR_VK_CALL(fGpu->vkInterface(), DestroyShaderModule(fGpu->device(), fragShaderModule,
                                                        nullptr));
    // This if check should not be needed since calling destroy on a VK_NULL_HANDLE is allowed.
    // However this is causing a crash in certain drivers (e.g. NVidia).
    if (this->primitiveProcessor().willUseGeoShader()) {
        GR_VK_CALL(fGpu->vkInterface(), DestroyShaderModule(fGpu->device(), geomShaderModule,
                                                            nullptr));
    }

    if (!pipeline) {
        GR_VK_CALL(fGpu->vkInterface(), DestroyPipelineLayout(fGpu->device(), pipelineLayout,
                                                              nullptr));
        this->cleanupFragmentProcessors();
        return nullptr;
    }

    return new GrVkPipelineState(fGpu,
                                 *desc,
                                 pipeline,
                                 pipelineLayout,
                                 samplerDSHandle,
                                 texelBufferDSHandle,
                                 fUniformHandles,
                                 fUniformHandler.fUniforms,
                                 fUniformHandler.fCurrentGeometryUBOOffset,
                                 fUniformHandler.fCurrentFragmentUBOOffset,
                                 (uint32_t)fUniformHandler.numSamplers(),
                                 (uint32_t)fUniformHandler.numTexelBuffers(),
                                 std::move(fGeometryProcessor),
                                 std::move(fXferProcessor),
                                 fFragmentProcessors);
}