#ifdef _WIN32
#define _CRT_SECURE_NO_WARNINGS
#define WIN32_LEAN_AND_MEAN
#endif

#include <fstream>
#include <filesystem>

#include "rt64_render_hooks.h"
#include "rt64_render_interface_builders.h"

#include "RmlUi/Core/RenderInterfaceCompatibility.h"

#include "ui_renderer.h"

#include "InterfaceVS.hlsl.spirv.h"
#include "InterfacePS.hlsl.spirv.h"

#ifdef _WIN32
#   include "InterfaceVS.hlsl.dxil.h"
#   include "InterfacePS.hlsl.dxil.h"
#elif defined(__APPLE__)
#   include "InterfaceVS.hlsl.metal.h"
#   include "InterfacePS.hlsl.metal.h"
#endif

#ifdef _WIN32
#    define GET_SHADER_BLOB(name, format) \
        ((format) == RT64::RenderShaderFormat::SPIRV ? name##BlobSPIRV : \
        (format) == RT64::RenderShaderFormat::DXIL ? name##BlobDXIL : nullptr)
#    define GET_SHADER_SIZE(name, format) \
        ((format) == RT64::RenderShaderFormat::SPIRV ? std::size(name##BlobSPIRV) : \
        (format) == RT64::RenderShaderFormat::DXIL ? std::size(name##BlobDXIL) : 0)
#elif defined(__APPLE__)
#    define GET_SHADER_BLOB(name, format) \
((format) == RT64::RenderShaderFormat::SPIRV ? name##BlobSPIRV : \
(format) == RT64::RenderShaderFormat::METAL ? name##BlobMSL : nullptr)
#    define GET_SHADER_SIZE(name, format) \
((format) == RT64::RenderShaderFormat::SPIRV ? std::size(name##BlobSPIRV) : \
(format) == RT64::RenderShaderFormat::METAL ? std::size(name##BlobMSL) : 0)
#else
#    define GET_SHADER_BLOB(name, format) \
        ((format) == RT64::RenderShaderFormat::SPIRV ? name##BlobSPIRV : nullptr)
#    define GET_SHADER_SIZE(name, format) \
        ((format) == RT64::RenderShaderFormat::SPIRV ? std::size(name##BlobSPIRV) : 0)
#endif

// TODO deduplicate from rt64_common.h
void CalculateTextureRowWidthPadding(uint32_t rowPitch, uint32_t &rowWidth, uint32_t &rowPadding) {
    const int RowMultiple = 256;
    rowWidth = rowPitch;
    rowPadding = (rowWidth % RowMultiple) ? RowMultiple - (rowWidth % RowMultiple) : 0;
    rowWidth += rowPadding;
}

struct RmlPushConstants {
    Rml::Matrix4f transform;
    Rml::Vector2f translation;
};

struct TextureHandle {
    std::unique_ptr<RT64::RenderTexture> texture;
    std::unique_ptr<RT64::RenderDescriptorSet> set;
};

static std::vector<char> read_file(const std::filesystem::path& filepath) {
    std::vector<char> ret{};
    std::ifstream input_file{ filepath, std::ios::binary };

    if (!input_file) {
        return ret;
    }

    input_file.seekg(0, std::ios::end);
    std::streampos filesize = input_file.tellg();
    input_file.seekg(0, std::ios::beg);

    ret.resize(filesize);

    input_file.read(ret.data(), filesize);

    return ret;
}


template <typename T>
T from_bytes_le(const char* input) {
    return *reinterpret_cast<const T*>(input);
}

namespace recompui {
class RmlRenderInterface_RT64_impl : public Rml::RenderInterfaceCompatibility {
    struct DynamicBuffer {
        std::unique_ptr<RT64::RenderBuffer> buffer_{};
        uint32_t size_ = 0;
        uint32_t bytes_used_ = 0;
        uint8_t* mapped_data_ = nullptr;
        RT64::RenderBufferFlags flags_ = RT64::RenderBufferFlag::NONE;
    };

    static constexpr uint32_t per_frame_descriptor_set = 0;
    static constexpr uint32_t per_draw_descriptor_set = 1;

    static constexpr uint32_t initial_upload_buffer_size = 1024 * 1024;
    static constexpr uint32_t initial_vertex_buffer_size = 512 * sizeof(Rml::Vertex);
    static constexpr uint32_t initial_index_buffer_size = 1024 * sizeof(int);
    static constexpr RT64::RenderFormat RmlTextureFormat = RT64::RenderFormat::R8G8B8A8_UNORM;
    static constexpr RT64::RenderFormat RmlTextureFormatBgra = RT64::RenderFormat::B8G8R8A8_UNORM;
    static constexpr RT64::RenderFormat SwapChainFormat = RT64::RenderFormat::B8G8R8A8_UNORM;
    static constexpr uint32_t RmlTextureFormatBytesPerPixel = RenderFormatSize(RmlTextureFormat);
    static_assert(RenderFormatSize(RmlTextureFormatBgra) == RmlTextureFormatBytesPerPixel);
    RT64::RenderInterface* interface_;
    RT64::RenderDevice* device_;
    int scissor_x_ = 0;
    int scissor_y_ = 0;
    int scissor_width_ = 0;
    int scissor_height_ = 0;
    int window_width_ = 0;
    int window_height_ = 0;
    RT64::RenderMultisampling multisampling_ = RT64::RenderMultisampling();
    Rml::Matrix4f projection_mtx_ = Rml::Matrix4f::Identity();
    Rml::Matrix4f transform_ = Rml::Matrix4f::Identity();
    Rml::Matrix4f mvp_ = Rml::Matrix4f::Identity();
    std::unordered_map<Rml::TextureHandle, TextureHandle> textures_{};
    Rml::TextureHandle texture_count_ = 1; // Start at 1 to reserve texture 0 as the 1x1 pixel white texture
    DynamicBuffer upload_buffer_;
    DynamicBuffer vertex_buffer_;
    DynamicBuffer index_buffer_;
    std::unique_ptr<RT64::RenderSampler> nearestSampler_{};
    std::unique_ptr<RT64::RenderSampler> linearSampler_{};
    std::unique_ptr<RT64::RenderShader> vertex_shader_{};
    std::unique_ptr<RT64::RenderShader> pixel_shader_{};
    std::unique_ptr<RT64::RenderDescriptorSet> sampler_set_{};
    std::unique_ptr<RT64::RenderDescriptorSetBuilder> texture_set_builder_{};
    std::unique_ptr<RT64::RenderPipelineLayout> layout_{};
    std::unique_ptr<RT64::RenderPipeline> pipeline_{};
    std::unique_ptr<RT64::RenderPipeline> pipeline_ms_{};
    std::unique_ptr<RT64::RenderTexture> screen_texture_ms_{};
    std::unique_ptr<RT64::RenderTexture> screen_texture_{};
    std::unique_ptr<RT64::RenderFramebuffer> screen_framebuffer_{};
    std::unique_ptr<RT64::RenderDescriptorSet> screen_descriptor_set_{};
    std::unique_ptr<RT64::RenderBuffer> screen_vertex_buffer_{};
    uint64_t screen_vertex_buffer_size_ = 0;
    uint32_t gTexture_descriptor_index;
    RT64::RenderInputSlot vertex_slot_{ 0, sizeof(Rml::Vertex) };
    RT64::RenderCommandList* list_ = nullptr;
    bool scissor_enabled_ = false;
    std::vector<std::unique_ptr<RT64::RenderBuffer>> stale_buffers_{};
public:
    RmlRenderInterface_RT64_impl(RT64::RenderInterface* interface, RT64::RenderDevice* device) {
        interface_ = interface;
        device_ = device;

        // Enable 4X MSAA if supported by the device.
        const RT64::RenderSampleCounts desired_sample_count = RT64::RenderSampleCount::COUNT_8;
        if (device_->getSampleCountsSupported(SwapChainFormat) & desired_sample_count) {
            multisampling_.sampleCount = desired_sample_count;
        }

        vertex_buffer_.flags_ = RT64::RenderBufferFlag::VERTEX;
        index_buffer_.flags_ = RT64::RenderBufferFlag::INDEX;

        // Create the texture upload buffer, vertex buffer and index buffer
        resize_dynamic_buffer(upload_buffer_, initial_upload_buffer_size, false);
        resize_dynamic_buffer(vertex_buffer_, initial_vertex_buffer_size, false);
        resize_dynamic_buffer(index_buffer_, initial_index_buffer_size, false);

        // Describe the vertex format
        std::vector<RT64::RenderInputElement> vertex_elements{};
        vertex_elements.emplace_back(RT64::RenderInputElement{ "POSITION", 0, 0, RT64::RenderFormat::R32G32_FLOAT, 0, offsetof(Rml::Vertex, position) });
        vertex_elements.emplace_back(RT64::RenderInputElement{ "COLOR", 0, 1, RT64::RenderFormat::R8G8B8A8_UNORM, 0, offsetof(Rml::Vertex, colour) });
        vertex_elements.emplace_back(RT64::RenderInputElement{ "TEXCOORD", 0, 2, RT64::RenderFormat::R32G32_FLOAT, 0, offsetof(Rml::Vertex, tex_coord) });

        // Create a nearest sampler and a linear sampler
        RT64::RenderSamplerDesc samplerDesc;
        samplerDesc.minFilter = RT64::RenderFilter::NEAREST;
        samplerDesc.magFilter = RT64::RenderFilter::NEAREST;
        samplerDesc.addressU = RT64::RenderTextureAddressMode::CLAMP;
        samplerDesc.addressV = RT64::RenderTextureAddressMode::CLAMP;
        samplerDesc.addressW = RT64::RenderTextureAddressMode::CLAMP;
        nearestSampler_ = device_->createSampler(samplerDesc);

        samplerDesc.minFilter = RT64::RenderFilter::LINEAR;
        samplerDesc.magFilter = RT64::RenderFilter::LINEAR;
        linearSampler_ = device_->createSampler(samplerDesc);

        // Create the shaders
        RT64::RenderShaderFormat shaderFormat = interface_->getCapabilities().shaderFormat;

        vertex_shader_ = device_->createShader(GET_SHADER_BLOB(InterfaceVS, shaderFormat), GET_SHADER_SIZE(InterfaceVS, shaderFormat), "VSMain", shaderFormat);
        pixel_shader_ = device_->createShader(GET_SHADER_BLOB(InterfacePS, shaderFormat), GET_SHADER_SIZE(InterfacePS, shaderFormat), "PSMain", shaderFormat);


        // Create the descriptor set that contains the sampler
        RT64::RenderDescriptorSetBuilder sampler_set_builder{};
        sampler_set_builder.begin();
        sampler_set_builder.addImmutableSampler(1, linearSampler_.get());
        sampler_set_builder.addConstantBuffer(3, 1); // Workaround D3D12 crash due to an empty RT64 descriptor set
        sampler_set_builder.end();
        sampler_set_ = sampler_set_builder.create(device_);

        // Create a builder for the descriptor sets that will contain textures
        texture_set_builder_ = std::make_unique<RT64::RenderDescriptorSetBuilder>();
        texture_set_builder_->begin();
        gTexture_descriptor_index = texture_set_builder_->addTexture(2);
        texture_set_builder_->end();

        // Create the pipeline layout
        RT64::RenderPipelineLayoutBuilder layout_builder{};
        layout_builder.begin(false, true);
        layout_builder.addPushConstant(0, 0, sizeof(RmlPushConstants), RT64::RenderShaderStageFlag::VERTEX);
        // Add the descriptor set for descriptors changed once per frame.
        layout_builder.addDescriptorSet(sampler_set_builder);
        // Add the descriptor set for descriptors changed once per draw.
        layout_builder.addDescriptorSet(*texture_set_builder_);
        layout_builder.end();
        layout_ = layout_builder.create(device_);

        // Create the pipeline description
        RT64::RenderGraphicsPipelineDesc pipeline_desc{};
        pipeline_desc.renderTargetBlend[0] = RT64::RenderBlendDesc::AlphaBlend();
        pipeline_desc.renderTargetFormat[0] = SwapChainFormat; // TODO: Use whatever format the swap chain was created with.
        pipeline_desc.renderTargetCount = 1;
        pipeline_desc.cullMode = RT64::RenderCullMode::NONE;
        pipeline_desc.inputSlots = &vertex_slot_;
        pipeline_desc.inputSlotsCount = 1;
        pipeline_desc.inputElements = vertex_elements.data();
        pipeline_desc.inputElementsCount = uint32_t(vertex_elements.size());
        pipeline_desc.pipelineLayout = layout_.get();
        pipeline_desc.primitiveTopology = RT64::RenderPrimitiveTopology::TRIANGLE_LIST;
        pipeline_desc.vertexShader = vertex_shader_.get();
        pipeline_desc.pixelShader = pixel_shader_.get();

        pipeline_ = device_->createGraphicsPipeline(pipeline_desc);

        if (multisampling_.sampleCount > 1) {
            pipeline_desc.multisampling = multisampling_;
            pipeline_ms_ = device_->createGraphicsPipeline(pipeline_desc);

            // Create the descriptor set for the screen drawer.
            RT64::RenderDescriptorRange screen_descriptor_range(RT64::RenderDescriptorRangeType::TEXTURE, 2, 1);
            screen_descriptor_set_ = device_->createDescriptorSet(RT64::RenderDescriptorSetDesc(&screen_descriptor_range, 1));

            // Create vertex buffer for the screen drawer (full-screen triangle).
            screen_vertex_buffer_size_ = sizeof(Rml::Vertex) * 3;
            screen_vertex_buffer_ = device_->createBuffer(RT64::RenderBufferDesc::VertexBuffer(screen_vertex_buffer_size_, RT64::RenderHeapType::UPLOAD));
            Rml::Vertex *vertices = (Rml::Vertex *)(screen_vertex_buffer_->map());
            const Rml::ColourbPremultiplied white(255, 255, 255, 255);
            vertices[0] = Rml::Vertex{ Rml::Vector2f(-1.0f, 1.0f), white, Rml::Vector2f(0.0f, 0.0f) };
            vertices[1] = Rml::Vertex{ Rml::Vector2f(-1.0f, -3.0f), white, Rml::Vector2f(0.0f, 2.0f) };
            vertices[2] = Rml::Vertex{ Rml::Vector2f(3.0f, 1.0f), white, Rml::Vector2f(2.0f, 0.0f) };
            screen_vertex_buffer_->unmap();
        }
    }

    void reset_dynamic_buffer(DynamicBuffer &dynamic_buffer) {
        assert(dynamic_buffer.mapped_data_ == nullptr);
        dynamic_buffer.bytes_used_ = 0;
        dynamic_buffer.mapped_data_ = reinterpret_cast<uint8_t*>(dynamic_buffer.buffer_->map());
    }

    void end_dynamic_buffer(DynamicBuffer &dynamic_buffer) {
        assert(dynamic_buffer.mapped_data_ != nullptr);
        dynamic_buffer.buffer_->unmap();
        dynamic_buffer.mapped_data_ = nullptr;
    }

    void resize_dynamic_buffer(DynamicBuffer &dynamic_buffer, uint32_t new_size, bool map = true) {
        // Unmap the buffer if it's mapped
        if (dynamic_buffer.mapped_data_ != nullptr) {
            dynamic_buffer.buffer_->unmap();
        }
        
        // If there's already a buffer, move it into the stale buffers so it persists until the start of next frame.
        if (dynamic_buffer.buffer_ != nullptr) {
            stale_buffers_.emplace_back(std::move(dynamic_buffer.buffer_));
        }

        // Create the new buffer, update the size and map it.
        dynamic_buffer.buffer_ = device_->createBuffer(RT64::RenderBufferDesc::UploadBuffer(new_size, dynamic_buffer.flags_));
        dynamic_buffer.size_ = new_size;
        dynamic_buffer.bytes_used_ = 0;

        if (map) {
            dynamic_buffer.mapped_data_ = reinterpret_cast<uint8_t*>(dynamic_buffer.buffer_->map());
        }
    }

    uint32_t allocate_dynamic_data(DynamicBuffer &dynamic_buffer, uint32_t num_bytes) {
        // Check if there's enough remaining room in the buffer to allocate the requested bytes.
        uint32_t total_bytes = num_bytes + dynamic_buffer.bytes_used_;

        if (total_bytes > dynamic_buffer.size_) {
            // There isn't, so mark the current buffer as stale and allocate a new one with 50% more space than the required amount.
            resize_dynamic_buffer(dynamic_buffer, total_bytes + total_bytes / 2);
        }

        // Record the current end of the buffer to return.
        uint32_t offset = dynamic_buffer.bytes_used_;

        // Bump the buffer's end forward by the number of bytes allocated.
        dynamic_buffer.bytes_used_ += num_bytes;

        return offset;
    }

    uint32_t allocate_dynamic_data_aligned(DynamicBuffer &dynamic_buffer, uint32_t num_bytes, uint32_t alignment) {
        // Check if there's enough remaining room in the buffer to allocate the requested bytes.
        uint32_t total_bytes = num_bytes + dynamic_buffer.bytes_used_;

        // Determine the amount of padding needed to meet the target alignment.
        uint32_t padding_bytes = ((dynamic_buffer.bytes_used_ + alignment - 1) / alignment) * alignment - dynamic_buffer.bytes_used_;

        // If there isn't enough room to allocate the required bytes plus the padding then resize the buffer and allocate from the start of the new one.
        if (total_bytes + padding_bytes > dynamic_buffer.size_) {
            resize_dynamic_buffer(dynamic_buffer, total_bytes + total_bytes / 2);

            dynamic_buffer.bytes_used_ += num_bytes;

            return 0;
        }

        // Otherwise allocate the padding and required bytes and offset the allocated position by the padding size.
        return allocate_dynamic_data(dynamic_buffer, padding_bytes + num_bytes) + padding_bytes;
    }

    void RenderGeometry(Rml::Vertex* vertices, int num_vertices, int* indices, int num_indices, Rml::TextureHandle texture, const Rml::Vector2f& translation) override {
        if (!textures_.contains(texture)) {
            if (texture == 0) {
                // Create a 1x1 pixel white texture as the first handle
                Rml::byte white_pixel[] = { 255, 255, 255, 255 };
                create_texture(0, white_pixel, Rml::Vector2i{ 1,1 });
            }
            else {
                assert(false && "Rendered without texture!");
            }
        }

        // Copy the vertex and index data into the mapped buffers.
        uint32_t vert_size_bytes = num_vertices * sizeof(*vertices);
        uint32_t index_size_bytes = num_indices * sizeof(*indices);
        uint32_t vertex_buffer_offset = allocate_dynamic_data(vertex_buffer_, vert_size_bytes);
        uint32_t index_buffer_offset = allocate_dynamic_data(index_buffer_, index_size_bytes);
        memcpy(vertex_buffer_.mapped_data_ + vertex_buffer_offset, vertices, vert_size_bytes);
        memcpy(index_buffer_.mapped_data_ + index_buffer_offset, indices, index_size_bytes);

        list_->setViewports(RT64::RenderViewport{ 0, 0, float(window_width_), float(window_height_) });
        if (scissor_enabled_) {
            list_->setScissors(RT64::RenderRect{
                scissor_x_,
                scissor_y_,
                (scissor_width_ + scissor_x_),
                (scissor_height_ + scissor_y_) });
        }
        else {
            list_->setScissors(RT64::RenderRect{ 0, 0, window_width_, window_height_ });
        }

        RT64::RenderIndexBufferView index_view{index_buffer_.buffer_->at(index_buffer_offset), index_size_bytes, RT64::RenderFormat::R32_UINT};
        list_->setIndexBuffer(&index_view);
        RT64::RenderVertexBufferView vertex_view{vertex_buffer_.buffer_->at(vertex_buffer_offset), vert_size_bytes};
        list_->setVertexBuffers(0, &vertex_view, 1, &vertex_slot_);
        list_->setGraphicsDescriptorSet(textures_.at(texture).set.get(), 1);

        RmlPushConstants constants{
            .transform = mvp_,
            .translation = translation
        };

        list_->setGraphicsPushConstants(0, &constants);

        list_->drawIndexedInstanced(num_indices, 1, 0, 0, 0);
    }

    void EnableScissorRegion(bool enable) override {
        scissor_enabled_ = enable;
    }

    void SetScissorRegion(int x, int y, int width, int height) override {
        scissor_x_ = x;
        scissor_y_ = y;
        scissor_width_ = width;
        scissor_height_ = height;
    }

    bool LoadTexture(Rml::TextureHandle& texture_handle, Rml::Vector2i& texture_dimensions, const Rml::String& source) override {
        std::filesystem::path image_path{ source.c_str() };

        if (image_path.extension() == ".tga") {
            std::vector<char> file_data = read_file(image_path);

            if (file_data.empty()) {
                printf("  File not found or empty\n");
                return false;
            }

            // Make sure ID length is zero
            if (file_data[0] != 0) {
                printf("  Nonzero ID length not supported\n");
                return false;
            }

            // Make sure no color map is used
            if (file_data[1] != 0) {
                printf("  Color maps not supported\n");
                return false;
            }

            // Make sure the image is uncompressed
            if (file_data[2] != 2) {
                printf("  Only uncompressed tga files supported\n");
                return false;
            }

            uint16_t origin_x = from_bytes_le<uint16_t>(file_data.data() + 8);
            uint16_t origin_y = from_bytes_le<uint16_t>(file_data.data() + 10);
            uint16_t size_x = from_bytes_le<uint16_t>(file_data.data() + 12);
            uint16_t size_y = from_bytes_le<uint16_t>(file_data.data() + 14);

            // Nonzero origin not supported
            if (origin_x != 0 || origin_y != 0) {
                printf("  Nonzero origin not supported\n");
                return false;
            }

            uint8_t pixel_depth = file_data[16];

            if (pixel_depth != 32) {
                printf("  Only 32bpp images supported\n");
                return false;
            }

            uint8_t image_descriptor = file_data[17];

            if ((image_descriptor & 0b1111) != 8) {
                printf("  Only 8bpp alpha supported\n");
            }

            if (image_descriptor & 0b110000) {
                printf("  Only bottom-to-top, left-to-right pixel order supported\n");
            }

            texture_dimensions.x = size_x;
            texture_dimensions.y = size_y;

            texture_handle = texture_count_++;
            create_texture(texture_handle, reinterpret_cast<const Rml::byte*>(file_data.data() + 18), texture_dimensions, true, true);

            return true;
        }

        return false;
    }

    bool GenerateTexture(Rml::TextureHandle& texture_handle, const Rml::byte* source, const Rml::Vector2i& source_dimensions) override {
        if (source_dimensions.x == 0 || source_dimensions.y == 0) {
            texture_handle = 0;
            return true;
        }

        texture_handle = texture_count_++;
        return create_texture(texture_handle, source, source_dimensions);
    }

    bool create_texture(Rml::TextureHandle texture_handle, const Rml::byte* source, const Rml::Vector2i& source_dimensions, bool flip_y = false, bool bgra = false) {
        std::unique_ptr<RT64::RenderTexture> texture =
            device_->createTexture(RT64::RenderTextureDesc::Texture2D(source_dimensions.x, source_dimensions.y, 1, bgra ? RmlTextureFormatBgra : RmlTextureFormat));

        if (texture != nullptr) {
            uint32_t image_size_bytes = source_dimensions.x * source_dimensions.y * RmlTextureFormatBytesPerPixel;

            // Calculate the texture padding for alignment purposes.
            uint32_t row_pitch = source_dimensions.x * RmlTextureFormatBytesPerPixel;
            uint32_t row_byte_width, row_byte_padding;
            CalculateTextureRowWidthPadding(row_pitch, row_byte_width, row_byte_padding);
            uint32_t row_width = row_byte_width / RmlTextureFormatBytesPerPixel;

            // Calculate the real number of bytes to upload including padding.
            uint32_t uploaded_size_bytes = row_byte_width * source_dimensions.y;

            // Allocate room in the upload buffer for the uploaded data.
            uint32_t upload_buffer_offset = allocate_dynamic_data_aligned(upload_buffer_, uploaded_size_bytes, 512);

            // Copy the source data into the upload buffer.
            uint8_t* dst_data = upload_buffer_.mapped_data_ + upload_buffer_offset;
                
            if (row_byte_padding == 0) {
                // Copy row-by-row if the image is flipped.
                if (flip_y) {
                    for (int row = 0; row < source_dimensions.y; row++) {
                        memcpy(dst_data + row_byte_width * (source_dimensions.y - row - 1), source + row_byte_width * row, row_byte_width);
                    }
                }
                // Directly copy if no padding is needed and the image isn't flipped.
                else {
                    memcpy(dst_data, source, image_size_bytes);
                }
            }
            // Otherwise pad each row as necessary.
            else {
                const Rml::byte *src_data = flip_y ? source + row_pitch * (source_dimensions.y - 1) : source;
                uint32_t src_stride = flip_y ? -row_pitch : row_pitch;

                for (int row = 0; row < source_dimensions.y; row++) {
                    memcpy(dst_data, src_data, row_pitch);
                    src_data += src_stride;
                    dst_data += row_byte_width;
                }
            }

            // Prepare the texture to be a destination for copying.
            list_->barriers(RT64::RenderBarrierStage::COPY, RT64::RenderTextureBarrier(texture.get(), RT64::RenderTextureLayout::COPY_DEST));
            
            // Copy the upload buffer into the texture.
            list_->copyTextureRegion(
                RT64::RenderTextureCopyLocation::Subresource(texture.get()),
                RT64::RenderTextureCopyLocation::PlacedFootprint(upload_buffer_.buffer_.get(), RmlTextureFormat, source_dimensions.x, source_dimensions.y, 1, row_width, upload_buffer_offset));
            
            // Prepare the texture for being read from a pixel shader.
            list_->barriers(RT64::RenderBarrierStage::GRAPHICS, RT64::RenderTextureBarrier(texture.get(), RT64::RenderTextureLayout::SHADER_READ));

            // Create a descriptor set with this texture in it.
            std::unique_ptr<RT64::RenderDescriptorSet> set = texture_set_builder_->create(device_);

            set->setTexture(gTexture_descriptor_index, texture.get(), RT64::RenderTextureLayout::SHADER_READ);

            textures_.emplace(texture_handle, TextureHandle{ std::move(texture), std::move(set) });

            return true;
        }

        return false;
    }

	void ReleaseTexture(Rml::TextureHandle texture) override {
        textures_.erase(texture);
    }

    void SetTransform(const Rml::Matrix4f* transform) override {
        transform_ = transform ? *transform : Rml::Matrix4f::Identity();
        recalculate_mvp();
    }

    void recalculate_mvp() {
        mvp_ = projection_mtx_ * transform_;
    }

    void start(RT64::RenderCommandList* list, int image_width, int image_height) {
        list_ = list;

        if (multisampling_.sampleCount > 1) {
            if (window_width_ != image_width || window_height_ != image_height) {
                screen_framebuffer_.reset();
                screen_texture_ = device_->createTexture(RT64::RenderTextureDesc::ColorTarget(image_width, image_height, SwapChainFormat));
                screen_texture_ms_ = device_->createTexture(RT64::RenderTextureDesc::ColorTarget(image_width, image_height, SwapChainFormat, multisampling_));
                const RT64::RenderTexture *color_attachment = screen_texture_ms_.get();
                screen_framebuffer_ = device_->createFramebuffer(RT64::RenderFramebufferDesc(&color_attachment, 1));
                screen_descriptor_set_->setTexture(0, screen_texture_.get(), RT64::RenderTextureLayout::SHADER_READ);
            }

            list_->setPipeline(pipeline_ms_.get());
        }
        else {
            list_->setPipeline(pipeline_.get());
        }

        list_->setGraphicsPipelineLayout(layout_.get());
        // Bind the set for descriptors that don't change across draws
        list_->setGraphicsDescriptorSet(sampler_set_.get(), 0);

        window_width_ = image_width;
        window_height_ = image_height;

        projection_mtx_ = Rml::Matrix4f::ProjectOrtho(0.0f, float(image_width), float(image_height), 0.0f, -10000, 10000);
        recalculate_mvp();

        // The following code assumes command lists aren't double buffered.
        // Clear out any stale buffers from the last command list.
        stale_buffers_.clear();

        // Reset buffers.
        reset_dynamic_buffer(upload_buffer_);
        reset_dynamic_buffer(vertex_buffer_);
        reset_dynamic_buffer(index_buffer_);

        // Set an internal texture as the render target if MSAA is enabled.
        if (multisampling_.sampleCount > 1) {
            list->barriers(RT64::RenderBarrierStage::GRAPHICS, RT64::RenderTextureBarrier(screen_texture_ms_.get(), RT64::RenderTextureLayout::COLOR_WRITE));
            list->setFramebuffer(screen_framebuffer_.get());
            list->clearColor(0, RT64::RenderColor(0.0f, 0.0f, 0.0f, 0.0f));
        }
    }

    void end(RT64::RenderCommandList* list, RT64::RenderFramebuffer* framebuffer) {
        // Draw the texture were rendered the UI in to the swap chain framebuffer if MSAA is enabled.
        if (multisampling_.sampleCount > 1) {
            RT64::RenderTextureBarrier before_resolve_barriers[] = {
                RT64::RenderTextureBarrier(screen_texture_ms_.get(), RT64::RenderTextureLayout::RESOLVE_SOURCE),
                RT64::RenderTextureBarrier(screen_texture_.get(), RT64::RenderTextureLayout::RESOLVE_DEST)
            };

            list->barriers(RT64::RenderBarrierStage::COPY, before_resolve_barriers, uint32_t(std::size(before_resolve_barriers)));
            list->resolveTexture(screen_texture_.get(), screen_texture_ms_.get());
            list->barriers(RT64::RenderBarrierStage::GRAPHICS, RT64::RenderTextureBarrier(screen_texture_.get(), RT64::RenderTextureLayout::SHADER_READ));
            list->setFramebuffer(framebuffer);
            list->setPipeline(pipeline_.get());
            list->setGraphicsPipelineLayout(layout_.get());
            list->setGraphicsDescriptorSet(sampler_set_.get(), 0);
            list->setGraphicsDescriptorSet(screen_descriptor_set_.get(), 1);
            RT64::RenderVertexBufferView vertex_view(screen_vertex_buffer_.get(), screen_vertex_buffer_size_);
            list->setVertexBuffers(0, &vertex_view, 1, &vertex_slot_);

            RmlPushConstants constants{
                .transform = Rml::Matrix4f::Identity(),
                .translation = Rml::Vector2f(0.0f, 0.0f)
            };

            list_->setGraphicsPushConstants(0, &constants);
            list->drawInstanced(3, 1, 0, 0);
        }

        end_dynamic_buffer(upload_buffer_);
        end_dynamic_buffer(vertex_buffer_);
        end_dynamic_buffer(index_buffer_);

        list_ = nullptr;
    }
};
} // namespace recompui

recompui::RmlRenderInterface_RT64::RmlRenderInterface_RT64() = default;
recompui::RmlRenderInterface_RT64::~RmlRenderInterface_RT64() = default;

void recompui::RmlRenderInterface_RT64::reset() {
    impl.reset();
}

void recompui::RmlRenderInterface_RT64::init(RT64::RenderInterface* interface, RT64::RenderDevice* device) {
    impl = std::make_unique<RmlRenderInterface_RT64_impl>(interface, device);
}

Rml::RenderInterface* recompui::RmlRenderInterface_RT64::get_rml_interface() {
    if (impl) {
        return impl->GetAdaptedInterface();
    }
    return nullptr;
}

void recompui::RmlRenderInterface_RT64::start(RT64::RenderCommandList* list, int image_width, int image_height) {
    assert(static_cast<bool>(impl));

    impl->start(list, image_width, image_height);
}

void recompui::RmlRenderInterface_RT64::end(RT64::RenderCommandList* list, RT64::RenderFramebuffer* framebuffer) {
    assert(static_cast<bool>(impl));

    impl->end(list, framebuffer);
}