// Copyright 2015 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#include <algorithm>
#include <array>
#include <bitset>
#include <memory>
#include <string>
#include <string_view>
#include <tuple>
#include <utility>
#include <glad/glad.h>
#include "common/alignment.h"
#include "common/assert.h"
#include "common/logging/log.h"
#include "common/math_util.h"
#include "common/microprofile.h"
#include "common/scope_exit.h"
#include "common/settings.h"
#include "core/core.h"
#include "core/hle/kernel/k_process.h"
#include "core/memory.h"
#include "video_core/engines/kepler_compute.h"
#include "video_core/engines/maxwell_3d.h"
#include "video_core/engines/shader_type.h"
#include "video_core/memory_manager.h"
#include "video_core/renderer_opengl/gl_device.h"
#include "video_core/renderer_opengl/gl_query_cache.h"
#include "video_core/renderer_opengl/gl_rasterizer.h"
#include "video_core/renderer_opengl/gl_shader_cache.h"
#include "video_core/renderer_opengl/gl_texture_cache.h"
#include "video_core/renderer_opengl/maxwell_to_gl.h"
#include "video_core/renderer_opengl/renderer_opengl.h"
#include "video_core/shader_cache.h"
#include "video_core/texture_cache/texture_cache.h"

namespace OpenGL {

using Maxwell = Tegra::Engines::Maxwell3D::Regs;
using GLvec4 = std::array<GLfloat, 4>;

using Tegra::Engines::ShaderType;
using VideoCore::Surface::PixelFormat;
using VideoCore::Surface::SurfaceTarget;
using VideoCore::Surface::SurfaceType;

MICROPROFILE_DEFINE(OpenGL_Drawing, "OpenGL", "Drawing", MP_RGB(128, 128, 192));
MICROPROFILE_DEFINE(OpenGL_Clears, "OpenGL", "Clears", MP_RGB(128, 128, 192));
MICROPROFILE_DEFINE(OpenGL_Blits, "OpenGL", "Blits", MP_RGB(128, 128, 192));
MICROPROFILE_DEFINE(OpenGL_CacheManagement, "OpenGL", "Cache Management", MP_RGB(100, 255, 100));

namespace {

constexpr size_t NUM_SUPPORTED_VERTEX_ATTRIBUTES = 16;

/// Translates hardware transform feedback indices
/// @param location Hardware location
/// @return Pair of ARB_transform_feedback3 token stream first and third arguments
/// @note Read https://www.khronos.org/registry/OpenGL/extensions/ARB/ARB_transform_feedback3.txt
std::pair<GLint, GLint> TransformFeedbackEnum(u8 location) {
    const u8 index = location / 4;
    if (index >= 8 && index <= 39) {
        return {GL_GENERIC_ATTRIB_NV, index - 8};
    }
    if (index >= 48 && index <= 55) {
        return {GL_TEXTURE_COORD_NV, index - 48};
    }
    switch (index) {
    case 7:
        return {GL_POSITION, 0};
    case 40:
        return {GL_PRIMARY_COLOR_NV, 0};
    case 41:
        return {GL_SECONDARY_COLOR_NV, 0};
    case 42:
        return {GL_BACK_PRIMARY_COLOR_NV, 0};
    case 43:
        return {GL_BACK_SECONDARY_COLOR_NV, 0};
    }
    UNIMPLEMENTED_MSG("index={}", index);
    return {GL_POSITION, 0};
}

void oglEnable(GLenum cap, bool state) {
    (state ? glEnable : glDisable)(cap);
}
} // Anonymous namespace

RasterizerOpenGL::RasterizerOpenGL(Core::Frontend::EmuWindow& emu_window_, Tegra::GPU& gpu_,
                                   Core::Memory::Memory& cpu_memory_, const Device& device_,
                                   ScreenInfo& screen_info_, ProgramManager& program_manager_,
                                   StateTracker& state_tracker_)
    : RasterizerAccelerated(cpu_memory_), gpu(gpu_), maxwell3d(gpu.Maxwell3D()),
      kepler_compute(gpu.KeplerCompute()), gpu_memory(gpu.MemoryManager()), device(device_),
      screen_info(screen_info_), program_manager(program_manager_), state_tracker(state_tracker_),
      texture_cache_runtime(device, program_manager, state_tracker),
      texture_cache(texture_cache_runtime, *this, maxwell3d, kepler_compute, gpu_memory),
      buffer_cache_runtime(device),
      buffer_cache(*this, maxwell3d, kepler_compute, gpu_memory, cpu_memory_, buffer_cache_runtime),
      shader_cache(*this, emu_window_, maxwell3d, kepler_compute, gpu_memory, device, texture_cache,
                   buffer_cache, program_manager, state_tracker),
      query_cache(*this, maxwell3d, gpu_memory), accelerate_dma(buffer_cache),
      fence_manager(*this, gpu, texture_cache, buffer_cache, query_cache) {}

RasterizerOpenGL::~RasterizerOpenGL() = default;

void RasterizerOpenGL::SyncVertexFormats() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::VertexFormats]) {
        return;
    }
    flags[Dirty::VertexFormats] = false;

    // Use the vertex array as-is, assumes that the data is formatted correctly for OpenGL. Enables
    // the first 16 vertex attributes always, as we don't know which ones are actually used until
    // shader time. Note, Tegra technically supports 32, but we're capping this to 16 for now to
    // avoid OpenGL errors.
    // TODO(Subv): Analyze the shader to identify which attributes are actually used and don't
    // assume every shader uses them all.
    for (std::size_t index = 0; index < NUM_SUPPORTED_VERTEX_ATTRIBUTES; ++index) {
        if (!flags[Dirty::VertexFormat0 + index]) {
            continue;
        }
        flags[Dirty::VertexFormat0 + index] = false;

        const auto attrib = maxwell3d.regs.vertex_attrib_format[index];
        const auto gl_index = static_cast<GLuint>(index);

        // Disable constant attributes.
        if (attrib.IsConstant()) {
            glDisableVertexAttribArray(gl_index);
            continue;
        }
        glEnableVertexAttribArray(gl_index);

        if (attrib.type == Maxwell::VertexAttribute::Type::SignedInt ||
            attrib.type == Maxwell::VertexAttribute::Type::UnsignedInt) {
            glVertexAttribIFormat(gl_index, attrib.ComponentCount(),
                                  MaxwellToGL::VertexFormat(attrib), attrib.offset);
        } else {
            glVertexAttribFormat(gl_index, attrib.ComponentCount(),
                                 MaxwellToGL::VertexFormat(attrib),
                                 attrib.IsNormalized() ? GL_TRUE : GL_FALSE, attrib.offset);
        }
        glVertexAttribBinding(gl_index, attrib.buffer);
    }
}

void RasterizerOpenGL::SyncVertexInstances() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::VertexInstances]) {
        return;
    }
    flags[Dirty::VertexInstances] = false;

    const auto& regs = maxwell3d.regs;
    for (std::size_t index = 0; index < NUM_SUPPORTED_VERTEX_ATTRIBUTES; ++index) {
        if (!flags[Dirty::VertexInstance0 + index]) {
            continue;
        }
        flags[Dirty::VertexInstance0 + index] = false;

        const auto gl_index = static_cast<GLuint>(index);
        const bool instancing_enabled = regs.instanced_arrays.IsInstancingEnabled(gl_index);
        const GLuint divisor = instancing_enabled ? regs.vertex_array[index].divisor : 0;
        glVertexBindingDivisor(gl_index, divisor);
    }
}

void RasterizerOpenGL::LoadDiskResources(u64 title_id, std::stop_token stop_loading,
                                         const VideoCore::DiskResourceLoadCallback& callback) {}

void RasterizerOpenGL::Clear() {
    MICROPROFILE_SCOPE(OpenGL_Clears);
    if (!maxwell3d.ShouldExecute()) {
        return;
    }

    const auto& regs = maxwell3d.regs;
    bool use_color{};
    bool use_depth{};
    bool use_stencil{};

    if (regs.clear_buffers.R || regs.clear_buffers.G || regs.clear_buffers.B ||
        regs.clear_buffers.A) {
        use_color = true;

        const GLuint index = regs.clear_buffers.RT;
        state_tracker.NotifyColorMask(index);
        glColorMaski(index, regs.clear_buffers.R != 0, regs.clear_buffers.G != 0,
                     regs.clear_buffers.B != 0, regs.clear_buffers.A != 0);

        // TODO(Rodrigo): Determine if clamping is used on clears
        SyncFragmentColorClampState();
        SyncFramebufferSRGB();
    }
    if (regs.clear_buffers.Z) {
        ASSERT_MSG(regs.zeta_enable != 0, "Tried to clear Z but buffer is not enabled!");
        use_depth = true;

        state_tracker.NotifyDepthMask();
        glDepthMask(GL_TRUE);
    }
    if (regs.clear_buffers.S) {
        ASSERT_MSG(regs.zeta_enable, "Tried to clear stencil but buffer is not enabled!");
        use_stencil = true;
    }

    if (!use_color && !use_depth && !use_stencil) {
        // No color surface nor depth/stencil surface are enabled
        return;
    }

    SyncRasterizeEnable();
    SyncStencilTestState();

    if (regs.clear_flags.scissor) {
        SyncScissorTest();
    } else {
        state_tracker.NotifyScissor0();
        glDisablei(GL_SCISSOR_TEST, 0);
    }
    UNIMPLEMENTED_IF(regs.clear_flags.viewport);

    std::scoped_lock lock{texture_cache.mutex};
    texture_cache.UpdateRenderTargets(true);
    state_tracker.BindFramebuffer(texture_cache.GetFramebuffer()->Handle());

    if (use_color) {
        glClearBufferfv(GL_COLOR, regs.clear_buffers.RT, regs.clear_color);
    }
    if (use_depth && use_stencil) {
        glClearBufferfi(GL_DEPTH_STENCIL, 0, regs.clear_depth, regs.clear_stencil);
    } else if (use_depth) {
        glClearBufferfv(GL_DEPTH, 0, &regs.clear_depth);
    } else if (use_stencil) {
        glClearBufferiv(GL_STENCIL, 0, &regs.clear_stencil);
    }
    ++num_queued_commands;
}

void RasterizerOpenGL::Draw(bool is_indexed, bool is_instanced) {
    MICROPROFILE_SCOPE(OpenGL_Drawing);

    query_cache.UpdateCounters();

    SyncState();

    GraphicsProgram* const program{shader_cache.CurrentGraphicsProgram()};

    std::scoped_lock lock{buffer_cache.mutex, texture_cache.mutex};
    program->Configure(is_indexed);

    const GLenum primitive_mode = MaxwellToGL::PrimitiveTopology(maxwell3d.regs.draw.topology);
    BeginTransformFeedback(primitive_mode);

    const GLuint base_instance = static_cast<GLuint>(maxwell3d.regs.vb_base_instance);
    const GLsizei num_instances =
        static_cast<GLsizei>(is_instanced ? maxwell3d.mme_draw.instance_count : 1);
    if (is_indexed) {
        const GLint base_vertex = static_cast<GLint>(maxwell3d.regs.vb_element_base);
        const GLsizei num_vertices = static_cast<GLsizei>(maxwell3d.regs.index_array.count);
        const GLvoid* const offset = buffer_cache_runtime.IndexOffset();
        const GLenum format = MaxwellToGL::IndexFormat(maxwell3d.regs.index_array.format);
        if (num_instances == 1 && base_instance == 0 && base_vertex == 0) {
            glDrawElements(primitive_mode, num_vertices, format, offset);
        } else if (num_instances == 1 && base_instance == 0) {
            glDrawElementsBaseVertex(primitive_mode, num_vertices, format, offset, base_vertex);
        } else if (base_vertex == 0 && base_instance == 0) {
            glDrawElementsInstanced(primitive_mode, num_vertices, format, offset, num_instances);
        } else if (base_vertex == 0) {
            glDrawElementsInstancedBaseInstance(primitive_mode, num_vertices, format, offset,
                                                num_instances, base_instance);
        } else if (base_instance == 0) {
            glDrawElementsInstancedBaseVertex(primitive_mode, num_vertices, format, offset,
                                              num_instances, base_vertex);
        } else {
            glDrawElementsInstancedBaseVertexBaseInstance(primitive_mode, num_vertices, format,
                                                          offset, num_instances, base_vertex,
                                                          base_instance);
        }
    } else {
        const GLint base_vertex = static_cast<GLint>(maxwell3d.regs.vertex_buffer.first);
        const GLsizei num_vertices = static_cast<GLsizei>(maxwell3d.regs.vertex_buffer.count);
        if (num_instances == 1 && base_instance == 0) {
            glDrawArrays(primitive_mode, base_vertex, num_vertices);
        } else if (base_instance == 0) {
            glDrawArraysInstanced(primitive_mode, base_vertex, num_vertices, num_instances);
        } else {
            glDrawArraysInstancedBaseInstance(primitive_mode, base_vertex, num_vertices,
                                              num_instances, base_instance);
        }
    }
    EndTransformFeedback();

    ++num_queued_commands;

    gpu.TickWork();
}

void RasterizerOpenGL::DispatchCompute() {
    ComputeProgram* const program{shader_cache.CurrentComputeProgram()};
    if (!program) {
        return;
    }
    program->Configure();
    const auto& qmd{kepler_compute.launch_description};
    glDispatchCompute(qmd.grid_dim_x, qmd.grid_dim_y, qmd.grid_dim_z);
    ++num_queued_commands;
}

void RasterizerOpenGL::ResetCounter(VideoCore::QueryType type) {
    query_cache.ResetCounter(type);
}

void RasterizerOpenGL::Query(GPUVAddr gpu_addr, VideoCore::QueryType type,
                             std::optional<u64> timestamp) {
    query_cache.Query(gpu_addr, type, timestamp);
}

void RasterizerOpenGL::BindGraphicsUniformBuffer(size_t stage, u32 index, GPUVAddr gpu_addr,
                                                 u32 size) {
    std::scoped_lock lock{buffer_cache.mutex};
    buffer_cache.BindGraphicsUniformBuffer(stage, index, gpu_addr, size);
}

void RasterizerOpenGL::DisableGraphicsUniformBuffer(size_t stage, u32 index) {
    buffer_cache.DisableGraphicsUniformBuffer(stage, index);
}

void RasterizerOpenGL::FlushAll() {}

void RasterizerOpenGL::FlushRegion(VAddr addr, u64 size) {
    MICROPROFILE_SCOPE(OpenGL_CacheManagement);
    if (addr == 0 || size == 0) {
        return;
    }
    {
        std::scoped_lock lock{texture_cache.mutex};
        texture_cache.DownloadMemory(addr, size);
    }
    {
        std::scoped_lock lock{buffer_cache.mutex};
        buffer_cache.DownloadMemory(addr, size);
    }
    query_cache.FlushRegion(addr, size);
}

bool RasterizerOpenGL::MustFlushRegion(VAddr addr, u64 size) {
    std::scoped_lock lock{buffer_cache.mutex, texture_cache.mutex};
    if (!Settings::IsGPULevelHigh()) {
        return buffer_cache.IsRegionGpuModified(addr, size);
    }
    return texture_cache.IsRegionGpuModified(addr, size) ||
           buffer_cache.IsRegionGpuModified(addr, size);
}

void RasterizerOpenGL::InvalidateRegion(VAddr addr, u64 size) {
    MICROPROFILE_SCOPE(OpenGL_CacheManagement);
    if (addr == 0 || size == 0) {
        return;
    }
    {
        std::scoped_lock lock{texture_cache.mutex};
        texture_cache.WriteMemory(addr, size);
    }
    {
        std::scoped_lock lock{buffer_cache.mutex};
        buffer_cache.WriteMemory(addr, size);
    }
    shader_cache.InvalidateRegion(addr, size);
    query_cache.InvalidateRegion(addr, size);
}

void RasterizerOpenGL::OnCPUWrite(VAddr addr, u64 size) {
    MICROPROFILE_SCOPE(OpenGL_CacheManagement);
    if (addr == 0 || size == 0) {
        return;
    }
    shader_cache.OnCPUWrite(addr, size);
    {
        std::scoped_lock lock{texture_cache.mutex};
        texture_cache.WriteMemory(addr, size);
    }
    {
        std::scoped_lock lock{buffer_cache.mutex};
        buffer_cache.CachedWriteMemory(addr, size);
    }
}

void RasterizerOpenGL::SyncGuestHost() {
    MICROPROFILE_SCOPE(OpenGL_CacheManagement);
    shader_cache.SyncGuestHost();
    {
        std::scoped_lock lock{buffer_cache.mutex};
        buffer_cache.FlushCachedWrites();
    }
}

void RasterizerOpenGL::UnmapMemory(VAddr addr, u64 size) {
    {
        std::scoped_lock lock{texture_cache.mutex};
        texture_cache.UnmapMemory(addr, size);
    }
    {
        std::scoped_lock lock{buffer_cache.mutex};
        buffer_cache.WriteMemory(addr, size);
    }
    shader_cache.OnCPUWrite(addr, size);
}

void RasterizerOpenGL::ModifyGPUMemory(GPUVAddr addr, u64 size) {
    {
        std::scoped_lock lock{texture_cache.mutex};
        texture_cache.UnmapGPUMemory(addr, size);
    }
}

void RasterizerOpenGL::SignalSemaphore(GPUVAddr addr, u32 value) {
    if (!gpu.IsAsync()) {
        gpu_memory.Write<u32>(addr, value);
        return;
    }
    fence_manager.SignalSemaphore(addr, value);
}

void RasterizerOpenGL::SignalSyncPoint(u32 value) {
    if (!gpu.IsAsync()) {
        gpu.IncrementSyncPoint(value);
        return;
    }
    fence_manager.SignalSyncPoint(value);
}

void RasterizerOpenGL::SignalReference() {
    if (!gpu.IsAsync()) {
        return;
    }
    fence_manager.SignalOrdering();
}

void RasterizerOpenGL::ReleaseFences() {
    if (!gpu.IsAsync()) {
        return;
    }
    fence_manager.WaitPendingFences();
}

void RasterizerOpenGL::FlushAndInvalidateRegion(VAddr addr, u64 size) {
    if (Settings::IsGPULevelExtreme()) {
        FlushRegion(addr, size);
    }
    InvalidateRegion(addr, size);
}

void RasterizerOpenGL::WaitForIdle() {
    glMemoryBarrier(GL_ALL_BARRIER_BITS);
    SignalReference();
}

void RasterizerOpenGL::FragmentBarrier() {
    glMemoryBarrier(GL_FRAMEBUFFER_BARRIER_BIT);
}

void RasterizerOpenGL::TiledCacheBarrier() {
    glTextureBarrier();
}

void RasterizerOpenGL::FlushCommands() {
    // Only flush when we have commands queued to OpenGL.
    if (num_queued_commands == 0) {
        return;
    }
    num_queued_commands = 0;
    glFlush();
}

void RasterizerOpenGL::TickFrame() {
    // Ticking a frame means that buffers will be swapped, calling glFlush implicitly.
    num_queued_commands = 0;

    fence_manager.TickFrame();
    {
        std::scoped_lock lock{texture_cache.mutex};
        texture_cache.TickFrame();
    }
    {
        std::scoped_lock lock{buffer_cache.mutex};
        buffer_cache.TickFrame();
    }
}

bool RasterizerOpenGL::AccelerateSurfaceCopy(const Tegra::Engines::Fermi2D::Surface& src,
                                             const Tegra::Engines::Fermi2D::Surface& dst,
                                             const Tegra::Engines::Fermi2D::Config& copy_config) {
    MICROPROFILE_SCOPE(OpenGL_Blits);
    std::scoped_lock lock{texture_cache.mutex};
    texture_cache.BlitImage(dst, src, copy_config);
    return true;
}

Tegra::Engines::AccelerateDMAInterface& RasterizerOpenGL::AccessAccelerateDMA() {
    return accelerate_dma;
}

bool RasterizerOpenGL::AccelerateDisplay(const Tegra::FramebufferConfig& config,
                                         VAddr framebuffer_addr, u32 pixel_stride) {
    if (framebuffer_addr == 0) {
        return false;
    }
    MICROPROFILE_SCOPE(OpenGL_CacheManagement);

    std::scoped_lock lock{texture_cache.mutex};
    ImageView* const image_view{texture_cache.TryFindFramebufferImageView(framebuffer_addr)};
    if (!image_view) {
        return false;
    }
    // Verify that the cached surface is the same size and format as the requested framebuffer
    // ASSERT_MSG(image_view->size.width == config.width, "Framebuffer width is different");
    // ASSERT_MSG(image_view->size.height == config.height, "Framebuffer height is different");

    screen_info.display_texture = image_view->Handle(Shader::TextureType::Color2D);
    screen_info.display_srgb = VideoCore::Surface::IsPixelFormatSRGB(image_view->format);
    return true;
}

void RasterizerOpenGL::SyncState() {
    SyncViewport();
    SyncRasterizeEnable();
    SyncPolygonModes();
    SyncColorMask();
    SyncFragmentColorClampState();
    SyncMultiSampleState();
    SyncDepthTestState();
    SyncDepthClamp();
    SyncStencilTestState();
    SyncBlendState();
    SyncLogicOpState();
    SyncCullMode();
    SyncPrimitiveRestart();
    SyncScissorTest();
    SyncPointState();
    SyncLineState();
    SyncPolygonOffset();
    SyncAlphaTest();
    SyncFramebufferSRGB();
    SyncVertexFormats();
    SyncVertexInstances();
}

void RasterizerOpenGL::SyncViewport() {
    auto& flags = maxwell3d.dirty.flags;
    const auto& regs = maxwell3d.regs;

    const bool dirty_viewport = flags[Dirty::Viewports];
    const bool dirty_clip_control = flags[Dirty::ClipControl];

    if (dirty_clip_control || flags[Dirty::FrontFace]) {
        flags[Dirty::FrontFace] = false;

        GLenum mode = MaxwellToGL::FrontFace(regs.front_face);
        if (regs.screen_y_control.triangle_rast_flip != 0 &&
            regs.viewport_transform[0].scale_y < 0.0f) {
            switch (mode) {
            case GL_CW:
                mode = GL_CCW;
                break;
            case GL_CCW:
                mode = GL_CW;
                break;
            }
        }
        glFrontFace(mode);
    }

    if (dirty_viewport || flags[Dirty::ClipControl]) {
        flags[Dirty::ClipControl] = false;

        bool flip_y = false;
        if (regs.viewport_transform[0].scale_y < 0.0f) {
            flip_y = !flip_y;
        }
        if (regs.screen_y_control.y_negate != 0) {
            flip_y = !flip_y;
        }
        const bool is_zero_to_one = regs.depth_mode == Maxwell::DepthMode::ZeroToOne;
        const GLenum origin = flip_y ? GL_UPPER_LEFT : GL_LOWER_LEFT;
        const GLenum depth = is_zero_to_one ? GL_ZERO_TO_ONE : GL_NEGATIVE_ONE_TO_ONE;
        state_tracker.ClipControl(origin, depth);
        state_tracker.SetYNegate(regs.screen_y_control.y_negate != 0);
    }

    if (dirty_viewport) {
        flags[Dirty::Viewports] = false;

        const bool force = flags[Dirty::ViewportTransform];
        flags[Dirty::ViewportTransform] = false;

        for (std::size_t i = 0; i < Maxwell::NumViewports; ++i) {
            if (!force && !flags[Dirty::Viewport0 + i]) {
                continue;
            }
            flags[Dirty::Viewport0 + i] = false;

            const auto& src = regs.viewport_transform[i];
            const Common::Rectangle<f32> rect{src.GetRect()};
            glViewportIndexedf(static_cast<GLuint>(i), rect.left, rect.bottom, rect.GetWidth(),
                               rect.GetHeight());

            const GLdouble reduce_z = regs.depth_mode == Maxwell::DepthMode::MinusOneToOne;
            const GLdouble near_depth = src.translate_z - src.scale_z * reduce_z;
            const GLdouble far_depth = src.translate_z + src.scale_z;
            if (device.HasDepthBufferFloat()) {
                glDepthRangeIndexeddNV(static_cast<GLuint>(i), near_depth, far_depth);
            } else {
                glDepthRangeIndexed(static_cast<GLuint>(i), near_depth, far_depth);
            }

            if (!GLAD_GL_NV_viewport_swizzle) {
                continue;
            }
            glViewportSwizzleNV(static_cast<GLuint>(i), MaxwellToGL::ViewportSwizzle(src.swizzle.x),
                                MaxwellToGL::ViewportSwizzle(src.swizzle.y),
                                MaxwellToGL::ViewportSwizzle(src.swizzle.z),
                                MaxwellToGL::ViewportSwizzle(src.swizzle.w));
        }
    }
}

void RasterizerOpenGL::SyncDepthClamp() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::DepthClampEnabled]) {
        return;
    }
    flags[Dirty::DepthClampEnabled] = false;

    oglEnable(GL_DEPTH_CLAMP, maxwell3d.regs.view_volume_clip_control.depth_clamp_disabled == 0);
}

void RasterizerOpenGL::SyncClipEnabled(u32 clip_mask) {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::ClipDistances] && !flags[VideoCommon::Dirty::Shaders]) {
        return;
    }
    flags[Dirty::ClipDistances] = false;

    clip_mask &= maxwell3d.regs.clip_distance_enabled;
    if (clip_mask == last_clip_distance_mask) {
        return;
    }
    last_clip_distance_mask = clip_mask;

    for (std::size_t i = 0; i < Maxwell::Regs::NumClipDistances; ++i) {
        oglEnable(static_cast<GLenum>(GL_CLIP_DISTANCE0 + i), (clip_mask >> i) & 1);
    }
}

void RasterizerOpenGL::SyncClipCoef() {
    UNIMPLEMENTED();
}

void RasterizerOpenGL::SyncCullMode() {
    auto& flags = maxwell3d.dirty.flags;
    const auto& regs = maxwell3d.regs;

    if (flags[Dirty::CullTest]) {
        flags[Dirty::CullTest] = false;

        if (regs.cull_test_enabled) {
            glEnable(GL_CULL_FACE);
            glCullFace(MaxwellToGL::CullFace(regs.cull_face));
        } else {
            glDisable(GL_CULL_FACE);
        }
    }
}

void RasterizerOpenGL::SyncPrimitiveRestart() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::PrimitiveRestart]) {
        return;
    }
    flags[Dirty::PrimitiveRestart] = false;

    if (maxwell3d.regs.primitive_restart.enabled) {
        glEnable(GL_PRIMITIVE_RESTART);
        glPrimitiveRestartIndex(maxwell3d.regs.primitive_restart.index);
    } else {
        glDisable(GL_PRIMITIVE_RESTART);
    }
}

void RasterizerOpenGL::SyncDepthTestState() {
    auto& flags = maxwell3d.dirty.flags;
    const auto& regs = maxwell3d.regs;

    if (flags[Dirty::DepthMask]) {
        flags[Dirty::DepthMask] = false;
        glDepthMask(regs.depth_write_enabled ? GL_TRUE : GL_FALSE);
    }

    if (flags[Dirty::DepthTest]) {
        flags[Dirty::DepthTest] = false;
        if (regs.depth_test_enable) {
            glEnable(GL_DEPTH_TEST);
            glDepthFunc(MaxwellToGL::ComparisonOp(regs.depth_test_func));
        } else {
            glDisable(GL_DEPTH_TEST);
        }
    }
}

void RasterizerOpenGL::SyncStencilTestState() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::StencilTest]) {
        return;
    }
    flags[Dirty::StencilTest] = false;

    const auto& regs = maxwell3d.regs;
    oglEnable(GL_STENCIL_TEST, regs.stencil_enable);

    glStencilFuncSeparate(GL_FRONT, MaxwellToGL::ComparisonOp(regs.stencil_front_func_func),
                          regs.stencil_front_func_ref, regs.stencil_front_func_mask);
    glStencilOpSeparate(GL_FRONT, MaxwellToGL::StencilOp(regs.stencil_front_op_fail),
                        MaxwellToGL::StencilOp(regs.stencil_front_op_zfail),
                        MaxwellToGL::StencilOp(regs.stencil_front_op_zpass));
    glStencilMaskSeparate(GL_FRONT, regs.stencil_front_mask);

    if (regs.stencil_two_side_enable) {
        glStencilFuncSeparate(GL_BACK, MaxwellToGL::ComparisonOp(regs.stencil_back_func_func),
                              regs.stencil_back_func_ref, regs.stencil_back_func_mask);
        glStencilOpSeparate(GL_BACK, MaxwellToGL::StencilOp(regs.stencil_back_op_fail),
                            MaxwellToGL::StencilOp(regs.stencil_back_op_zfail),
                            MaxwellToGL::StencilOp(regs.stencil_back_op_zpass));
        glStencilMaskSeparate(GL_BACK, regs.stencil_back_mask);
    } else {
        glStencilFuncSeparate(GL_BACK, GL_ALWAYS, 0, 0xFFFFFFFF);
        glStencilOpSeparate(GL_BACK, GL_KEEP, GL_KEEP, GL_KEEP);
        glStencilMaskSeparate(GL_BACK, 0xFFFFFFFF);
    }
}

void RasterizerOpenGL::SyncRasterizeEnable() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::RasterizeEnable]) {
        return;
    }
    flags[Dirty::RasterizeEnable] = false;

    oglEnable(GL_RASTERIZER_DISCARD, maxwell3d.regs.rasterize_enable == 0);
}

void RasterizerOpenGL::SyncPolygonModes() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::PolygonModes]) {
        return;
    }
    flags[Dirty::PolygonModes] = false;

    const auto& regs = maxwell3d.regs;
    if (regs.fill_rectangle) {
        if (!GLAD_GL_NV_fill_rectangle) {
            LOG_ERROR(Render_OpenGL, "GL_NV_fill_rectangle used and not supported");
            glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
            return;
        }

        flags[Dirty::PolygonModeFront] = true;
        flags[Dirty::PolygonModeBack] = true;
        glPolygonMode(GL_FRONT_AND_BACK, GL_FILL_RECTANGLE_NV);
        return;
    }

    if (regs.polygon_mode_front == regs.polygon_mode_back) {
        flags[Dirty::PolygonModeFront] = false;
        flags[Dirty::PolygonModeBack] = false;
        glPolygonMode(GL_FRONT_AND_BACK, MaxwellToGL::PolygonMode(regs.polygon_mode_front));
        return;
    }

    if (flags[Dirty::PolygonModeFront]) {
        flags[Dirty::PolygonModeFront] = false;
        glPolygonMode(GL_FRONT, MaxwellToGL::PolygonMode(regs.polygon_mode_front));
    }

    if (flags[Dirty::PolygonModeBack]) {
        flags[Dirty::PolygonModeBack] = false;
        glPolygonMode(GL_BACK, MaxwellToGL::PolygonMode(regs.polygon_mode_back));
    }
}

void RasterizerOpenGL::SyncColorMask() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::ColorMasks]) {
        return;
    }
    flags[Dirty::ColorMasks] = false;

    const bool force = flags[Dirty::ColorMaskCommon];
    flags[Dirty::ColorMaskCommon] = false;

    const auto& regs = maxwell3d.regs;
    if (regs.color_mask_common) {
        if (!force && !flags[Dirty::ColorMask0]) {
            return;
        }
        flags[Dirty::ColorMask0] = false;

        auto& mask = regs.color_mask[0];
        glColorMask(mask.R != 0, mask.B != 0, mask.G != 0, mask.A != 0);
        return;
    }

    // Path without color_mask_common set
    for (std::size_t i = 0; i < Maxwell::NumRenderTargets; ++i) {
        if (!force && !flags[Dirty::ColorMask0 + i]) {
            continue;
        }
        flags[Dirty::ColorMask0 + i] = false;

        const auto& mask = regs.color_mask[i];
        glColorMaski(static_cast<GLuint>(i), mask.R != 0, mask.G != 0, mask.B != 0, mask.A != 0);
    }
}

void RasterizerOpenGL::SyncMultiSampleState() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::MultisampleControl]) {
        return;
    }
    flags[Dirty::MultisampleControl] = false;

    const auto& regs = maxwell3d.regs;
    oglEnable(GL_SAMPLE_ALPHA_TO_COVERAGE, regs.multisample_control.alpha_to_coverage);
    oglEnable(GL_SAMPLE_ALPHA_TO_ONE, regs.multisample_control.alpha_to_one);
}

void RasterizerOpenGL::SyncFragmentColorClampState() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::FragmentClampColor]) {
        return;
    }
    flags[Dirty::FragmentClampColor] = false;

    glClampColor(GL_CLAMP_FRAGMENT_COLOR, maxwell3d.regs.frag_color_clamp ? GL_TRUE : GL_FALSE);
}

void RasterizerOpenGL::SyncBlendState() {
    auto& flags = maxwell3d.dirty.flags;
    const auto& regs = maxwell3d.regs;

    if (flags[Dirty::BlendColor]) {
        flags[Dirty::BlendColor] = false;
        glBlendColor(regs.blend_color.r, regs.blend_color.g, regs.blend_color.b,
                     regs.blend_color.a);
    }

    // TODO(Rodrigo): Revisit blending, there are several registers we are not reading

    if (!flags[Dirty::BlendStates]) {
        return;
    }
    flags[Dirty::BlendStates] = false;

    if (!regs.independent_blend_enable) {
        if (!regs.blend.enable[0]) {
            glDisable(GL_BLEND);
            return;
        }
        glEnable(GL_BLEND);
        glBlendFuncSeparate(MaxwellToGL::BlendFunc(regs.blend.factor_source_rgb),
                            MaxwellToGL::BlendFunc(regs.blend.factor_dest_rgb),
                            MaxwellToGL::BlendFunc(regs.blend.factor_source_a),
                            MaxwellToGL::BlendFunc(regs.blend.factor_dest_a));
        glBlendEquationSeparate(MaxwellToGL::BlendEquation(regs.blend.equation_rgb),
                                MaxwellToGL::BlendEquation(regs.blend.equation_a));
        return;
    }

    const bool force = flags[Dirty::BlendIndependentEnabled];
    flags[Dirty::BlendIndependentEnabled] = false;

    for (std::size_t i = 0; i < Maxwell::NumRenderTargets; ++i) {
        if (!force && !flags[Dirty::BlendState0 + i]) {
            continue;
        }
        flags[Dirty::BlendState0 + i] = false;

        if (!regs.blend.enable[i]) {
            glDisablei(GL_BLEND, static_cast<GLuint>(i));
            continue;
        }
        glEnablei(GL_BLEND, static_cast<GLuint>(i));

        const auto& src = regs.independent_blend[i];
        glBlendFuncSeparatei(static_cast<GLuint>(i), MaxwellToGL::BlendFunc(src.factor_source_rgb),
                             MaxwellToGL::BlendFunc(src.factor_dest_rgb),
                             MaxwellToGL::BlendFunc(src.factor_source_a),
                             MaxwellToGL::BlendFunc(src.factor_dest_a));
        glBlendEquationSeparatei(static_cast<GLuint>(i),
                                 MaxwellToGL::BlendEquation(src.equation_rgb),
                                 MaxwellToGL::BlendEquation(src.equation_a));
    }
}

void RasterizerOpenGL::SyncLogicOpState() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::LogicOp]) {
        return;
    }
    flags[Dirty::LogicOp] = false;

    const auto& regs = maxwell3d.regs;
    if (regs.logic_op.enable) {
        glEnable(GL_COLOR_LOGIC_OP);
        glLogicOp(MaxwellToGL::LogicOp(regs.logic_op.operation));
    } else {
        glDisable(GL_COLOR_LOGIC_OP);
    }
}

void RasterizerOpenGL::SyncScissorTest() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::Scissors]) {
        return;
    }
    flags[Dirty::Scissors] = false;

    const auto& regs = maxwell3d.regs;
    for (std::size_t index = 0; index < Maxwell::NumViewports; ++index) {
        if (!flags[Dirty::Scissor0 + index]) {
            continue;
        }
        flags[Dirty::Scissor0 + index] = false;

        const auto& src = regs.scissor_test[index];
        if (src.enable) {
            glEnablei(GL_SCISSOR_TEST, static_cast<GLuint>(index));
            glScissorIndexed(static_cast<GLuint>(index), src.min_x, src.min_y,
                             src.max_x - src.min_x, src.max_y - src.min_y);
        } else {
            glDisablei(GL_SCISSOR_TEST, static_cast<GLuint>(index));
        }
    }
}

void RasterizerOpenGL::SyncPointState() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::PointSize]) {
        return;
    }
    flags[Dirty::PointSize] = false;

    oglEnable(GL_POINT_SPRITE, maxwell3d.regs.point_sprite_enable);
    oglEnable(GL_PROGRAM_POINT_SIZE, maxwell3d.regs.vp_point_size.enable);

    glPointSize(std::max(1.0f, maxwell3d.regs.point_size));
}

void RasterizerOpenGL::SyncLineState() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::LineWidth]) {
        return;
    }
    flags[Dirty::LineWidth] = false;

    const auto& regs = maxwell3d.regs;
    oglEnable(GL_LINE_SMOOTH, regs.line_smooth_enable);
    glLineWidth(regs.line_smooth_enable ? regs.line_width_smooth : regs.line_width_aliased);
}

void RasterizerOpenGL::SyncPolygonOffset() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::PolygonOffset]) {
        return;
    }
    flags[Dirty::PolygonOffset] = false;

    const auto& regs = maxwell3d.regs;
    oglEnable(GL_POLYGON_OFFSET_FILL, regs.polygon_offset_fill_enable);
    oglEnable(GL_POLYGON_OFFSET_LINE, regs.polygon_offset_line_enable);
    oglEnable(GL_POLYGON_OFFSET_POINT, regs.polygon_offset_point_enable);

    if (regs.polygon_offset_fill_enable || regs.polygon_offset_line_enable ||
        regs.polygon_offset_point_enable) {
        // Hardware divides polygon offset units by two
        glPolygonOffsetClamp(regs.polygon_offset_factor, regs.polygon_offset_units / 2.0f,
                             regs.polygon_offset_clamp);
    }
}

void RasterizerOpenGL::SyncAlphaTest() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::AlphaTest]) {
        return;
    }
    flags[Dirty::AlphaTest] = false;

    const auto& regs = maxwell3d.regs;
    if (regs.alpha_test_enabled) {
        glEnable(GL_ALPHA_TEST);
        glAlphaFunc(MaxwellToGL::ComparisonOp(regs.alpha_test_func), regs.alpha_test_ref);
    } else {
        glDisable(GL_ALPHA_TEST);
    }
}

void RasterizerOpenGL::SyncFramebufferSRGB() {
    auto& flags = maxwell3d.dirty.flags;
    if (!flags[Dirty::FramebufferSRGB]) {
        return;
    }
    flags[Dirty::FramebufferSRGB] = false;

    oglEnable(GL_FRAMEBUFFER_SRGB, maxwell3d.regs.framebuffer_srgb);
}

void RasterizerOpenGL::SyncTransformFeedback() {
    // TODO(Rodrigo): Inject SKIP_COMPONENTS*_NV when required. An unimplemented message will signal
    // when this is required.
    const auto& regs = maxwell3d.regs;

    static constexpr std::size_t STRIDE = 3;
    std::array<GLint, 128 * STRIDE * Maxwell::NumTransformFeedbackBuffers> attribs;
    std::array<GLint, Maxwell::NumTransformFeedbackBuffers> streams;

    GLint* cursor = attribs.data();
    GLint* current_stream = streams.data();

    for (std::size_t feedback = 0; feedback < Maxwell::NumTransformFeedbackBuffers; ++feedback) {
        const auto& layout = regs.tfb_layouts[feedback];
        UNIMPLEMENTED_IF_MSG(layout.stride != layout.varying_count * 4, "Stride padding");
        if (layout.varying_count == 0) {
            continue;
        }

        *current_stream = static_cast<GLint>(feedback);
        if (current_stream != streams.data()) {
            // When stepping one stream, push the expected token
            cursor[0] = GL_NEXT_BUFFER_NV;
            cursor[1] = 0;
            cursor[2] = 0;
            cursor += STRIDE;
        }
        ++current_stream;

        const auto& locations = regs.tfb_varying_locs[feedback];
        std::optional<u8> current_index;
        for (u32 offset = 0; offset < layout.varying_count; ++offset) {
            const u8 location = locations[offset];
            const u8 index = location / 4;

            if (current_index == index) {
                // Increase number of components of the previous attachment
                ++cursor[-2];
                continue;
            }
            current_index = index;

            std::tie(cursor[0], cursor[2]) = TransformFeedbackEnum(location);
            cursor[1] = 1;
            cursor += STRIDE;
        }
    }

    const GLsizei num_attribs = static_cast<GLsizei>((cursor - attribs.data()) / STRIDE);
    const GLsizei num_strides = static_cast<GLsizei>(current_stream - streams.data());
    glTransformFeedbackStreamAttribsNV(num_attribs, attribs.data(), num_strides, streams.data(),
                                       GL_INTERLEAVED_ATTRIBS);
}

void RasterizerOpenGL::BeginTransformFeedback(GLenum primitive_mode) {
    const auto& regs = maxwell3d.regs;
    if (regs.tfb_enabled == 0) {
        return;
    }
    if (device.UseAssemblyShaders()) {
        SyncTransformFeedback();
    }
    UNIMPLEMENTED_IF(regs.IsShaderConfigEnabled(Maxwell::ShaderProgram::TesselationControl) ||
                     regs.IsShaderConfigEnabled(Maxwell::ShaderProgram::TesselationEval) ||
                     regs.IsShaderConfigEnabled(Maxwell::ShaderProgram::Geometry));
    UNIMPLEMENTED_IF(primitive_mode != GL_POINTS);

    // We may have to call BeginTransformFeedbackNV here since they seem to call different
    // implementations on Nvidia's driver (the pointer is different) but we are using
    // ARB_transform_feedback3 features with NV_transform_feedback interactions and the ARB
    // extension doesn't define BeginTransformFeedback (without NV) interactions. It just works.
    glBeginTransformFeedback(GL_POINTS);
}

void RasterizerOpenGL::EndTransformFeedback() {
    const auto& regs = maxwell3d.regs;
    if (regs.tfb_enabled == 0) {
        return;
    }
    glEndTransformFeedback();
}

AccelerateDMA::AccelerateDMA(BufferCache& buffer_cache_) : buffer_cache{buffer_cache_} {}

bool AccelerateDMA::BufferCopy(GPUVAddr src_address, GPUVAddr dest_address, u64 amount) {
    std::scoped_lock lock{buffer_cache.mutex};
    return buffer_cache.DMACopy(src_address, dest_address, amount);
}

bool AccelerateDMA::BufferClear(GPUVAddr src_address, u64 amount, u32 value) {
    std::scoped_lock lock{buffer_cache.mutex};
    return buffer_cache.DMAClear(src_address, amount, value);
}

} // namespace OpenGL
