// SPDX-FileCopyrightText: Copyright 2019 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later

#include <algorithm>
#include <cstring>

#include "common/bit_cast.h"
#include "common/cityhash.h"
#include "common/common_types.h"
#include "video_core/renderer_vulkan/fixed_pipeline_state.h"
#include "video_core/renderer_vulkan/vk_state_tracker.h"

namespace Vulkan {
namespace {
constexpr size_t POINT = 0;
constexpr size_t LINE = 1;
constexpr size_t POLYGON = 2;
constexpr std::array POLYGON_OFFSET_ENABLE_LUT = {
    POINT,   // Points
    LINE,    // Lines
    LINE,    // LineLoop
    LINE,    // LineStrip
    POLYGON, // Triangles
    POLYGON, // TriangleStrip
    POLYGON, // TriangleFan
    POLYGON, // Quads
    POLYGON, // QuadStrip
    POLYGON, // Polygon
    LINE,    // LinesAdjacency
    LINE,    // LineStripAdjacency
    POLYGON, // TrianglesAdjacency
    POLYGON, // TriangleStripAdjacency
    POLYGON, // Patches
};

void RefreshXfbState(VideoCommon::TransformFeedbackState& state, const Maxwell& regs) {
    std::ranges::transform(regs.tfb_layouts, state.layouts.begin(), [](const auto& layout) {
        return VideoCommon::TransformFeedbackState::Layout{
            .stream = layout.stream,
            .varying_count = layout.varying_count,
            .stride = layout.stride,
        };
    });
    state.varyings = regs.tfb_varying_locs;
}
} // Anonymous namespace

void FixedPipelineState::Refresh(Tegra::Engines::Maxwell3D& maxwell3d,
                                 bool has_extended_dynamic_state, bool has_dynamic_vertex_input) {
    const Maxwell& regs = maxwell3d.regs;
    const std::array enabled_lut{
        regs.polygon_offset_point_enable,
        regs.polygon_offset_line_enable,
        regs.polygon_offset_fill_enable,
    };
    const u32 topology_index = static_cast<u32>(regs.draw.topology.Value());

    raw1 = 0;
    extended_dynamic_state.Assign(has_extended_dynamic_state ? 1 : 0);
    dynamic_vertex_input.Assign(has_dynamic_vertex_input ? 1 : 0);
    xfb_enabled.Assign(regs.tfb_enabled != 0);
    primitive_restart_enable.Assign(regs.primitive_restart.enabled != 0 ? 1 : 0);
    depth_bias_enable.Assign(enabled_lut[POLYGON_OFFSET_ENABLE_LUT[topology_index]] != 0 ? 1 : 0);
    depth_clamp_disabled.Assign(regs.view_volume_clip_control.depth_clamp_disabled.Value());
    ndc_minus_one_to_one.Assign(regs.depth_mode == Maxwell::DepthMode::MinusOneToOne ? 1 : 0);
    polygon_mode.Assign(PackPolygonMode(regs.polygon_mode_front));
    patch_control_points_minus_one.Assign(regs.patch_vertices - 1);
    tessellation_primitive.Assign(static_cast<u32>(regs.tess_mode.prim.Value()));
    tessellation_spacing.Assign(static_cast<u32>(regs.tess_mode.spacing.Value()));
    tessellation_clockwise.Assign(regs.tess_mode.cw.Value());
    logic_op_enable.Assign(regs.logic_op.enable != 0 ? 1 : 0);
    logic_op.Assign(PackLogicOp(regs.logic_op.operation));
    topology.Assign(regs.draw.topology);
    msaa_mode.Assign(regs.multisample_mode);

    raw2 = 0;
    rasterize_enable.Assign(regs.rasterize_enable != 0 ? 1 : 0);
    const auto test_func =
        regs.alpha_test_enabled != 0 ? regs.alpha_test_func : Maxwell::ComparisonOp::Always;
    alpha_test_func.Assign(PackComparisonOp(test_func));
    early_z.Assign(regs.force_early_fragment_tests != 0 ? 1 : 0);
    depth_enabled.Assign(regs.zeta_enable != 0 ? 1 : 0);
    depth_format.Assign(static_cast<u32>(regs.zeta.format));
    y_negate.Assign(regs.screen_y_control.y_negate != 0 ? 1 : 0);
    provoking_vertex_last.Assign(regs.provoking_vertex_last != 0 ? 1 : 0);
    conservative_raster_enable.Assign(regs.conservative_raster_enable != 0 ? 1 : 0);
    smooth_lines.Assign(regs.line_smooth_enable != 0 ? 1 : 0);

    for (size_t i = 0; i < regs.rt.size(); ++i) {
        color_formats[i] = static_cast<u8>(regs.rt[i].format);
    }
    alpha_test_ref = Common::BitCast<u32>(regs.alpha_test_ref);
    point_size = Common::BitCast<u32>(regs.point_size);

    if (maxwell3d.dirty.flags[Dirty::VertexInput]) {
        if (has_dynamic_vertex_input) {
            // Dirty flag will be reset by the command buffer update
            static constexpr std::array LUT{
                0u, // Invalid
                1u, // SignedNorm
                1u, // UnsignedNorm
                2u, // SignedInt
                3u, // UnsignedInt
                1u, // UnsignedScaled
                1u, // SignedScaled
                1u, // Float
            };
            const auto& attrs = regs.vertex_attrib_format;
            attribute_types = 0;
            for (size_t i = 0; i < Maxwell::NumVertexAttributes; ++i) {
                const u32 mask = attrs[i].constant != 0 ? 0 : 3;
                const u32 type = LUT[static_cast<size_t>(attrs[i].type.Value())];
                attribute_types |= static_cast<u64>(type & mask) << (i * 2);
            }
        } else {
            maxwell3d.dirty.flags[Dirty::VertexInput] = false;
            enabled_divisors = 0;
            for (size_t index = 0; index < Maxwell::NumVertexArrays; ++index) {
                const bool is_enabled = regs.instanced_arrays.IsInstancingEnabled(index);
                binding_divisors[index] = is_enabled ? regs.vertex_array[index].divisor : 0;
                enabled_divisors |= (is_enabled ? u64{1} : 0) << index;
            }
            for (size_t index = 0; index < Maxwell::NumVertexAttributes; ++index) {
                const auto& input = regs.vertex_attrib_format[index];
                auto& attribute = attributes[index];
                attribute.raw = 0;
                attribute.enabled.Assign(input.constant ? 0 : 1);
                attribute.buffer.Assign(input.buffer);
                attribute.offset.Assign(input.offset);
                attribute.type.Assign(static_cast<u32>(input.type.Value()));
                attribute.size.Assign(static_cast<u32>(input.size.Value()));
            }
        }
    }
    if (maxwell3d.dirty.flags[Dirty::Blending]) {
        maxwell3d.dirty.flags[Dirty::Blending] = false;
        for (size_t index = 0; index < attachments.size(); ++index) {
            attachments[index].Refresh(regs, index);
        }
    }
    if (maxwell3d.dirty.flags[Dirty::ViewportSwizzles]) {
        maxwell3d.dirty.flags[Dirty::ViewportSwizzles] = false;
        const auto& transform = regs.viewport_transform;
        std::ranges::transform(transform, viewport_swizzles.begin(), [](const auto& viewport) {
            return static_cast<u16>(viewport.swizzle.raw);
        });
    }
    if (!extended_dynamic_state) {
        dynamic_state.Refresh(regs);
    }
    if (xfb_enabled) {
        RefreshXfbState(xfb_state, regs);
    }
}

void FixedPipelineState::BlendingAttachment::Refresh(const Maxwell& regs, size_t index) {
    const auto& mask = regs.color_mask[regs.color_mask_common ? 0 : index];

    raw = 0;
    mask_r.Assign(mask.R);
    mask_g.Assign(mask.G);
    mask_b.Assign(mask.B);
    mask_a.Assign(mask.A);

    // TODO: C++20 Use templated lambda to deduplicate code

    if (!regs.independent_blend_enable) {
        const auto& src = regs.blend;
        if (!src.enable[index]) {
            return;
        }
        equation_rgb.Assign(PackBlendEquation(src.equation_rgb));
        equation_a.Assign(PackBlendEquation(src.equation_a));
        factor_source_rgb.Assign(PackBlendFactor(src.factor_source_rgb));
        factor_dest_rgb.Assign(PackBlendFactor(src.factor_dest_rgb));
        factor_source_a.Assign(PackBlendFactor(src.factor_source_a));
        factor_dest_a.Assign(PackBlendFactor(src.factor_dest_a));
        enable.Assign(1);
        return;
    }

    if (!regs.blend.enable[index]) {
        return;
    }
    const auto& src = regs.independent_blend[index];
    equation_rgb.Assign(PackBlendEquation(src.equation_rgb));
    equation_a.Assign(PackBlendEquation(src.equation_a));
    factor_source_rgb.Assign(PackBlendFactor(src.factor_source_rgb));
    factor_dest_rgb.Assign(PackBlendFactor(src.factor_dest_rgb));
    factor_source_a.Assign(PackBlendFactor(src.factor_source_a));
    factor_dest_a.Assign(PackBlendFactor(src.factor_dest_a));
    enable.Assign(1);
}

void FixedPipelineState::DynamicState::Refresh(const Maxwell& regs) {
    u32 packed_front_face = PackFrontFace(regs.front_face);
    if (regs.screen_y_control.triangle_rast_flip != 0) {
        // Flip front face
        packed_front_face = 1 - packed_front_face;
    }

    raw1 = 0;
    raw2 = 0;
    front.action_stencil_fail.Assign(PackStencilOp(regs.stencil_front_op_fail));
    front.action_depth_fail.Assign(PackStencilOp(regs.stencil_front_op_zfail));
    front.action_depth_pass.Assign(PackStencilOp(regs.stencil_front_op_zpass));
    front.test_func.Assign(PackComparisonOp(regs.stencil_front_func_func));
    if (regs.stencil_two_side_enable) {
        back.action_stencil_fail.Assign(PackStencilOp(regs.stencil_back_op_fail));
        back.action_depth_fail.Assign(PackStencilOp(regs.stencil_back_op_zfail));
        back.action_depth_pass.Assign(PackStencilOp(regs.stencil_back_op_zpass));
        back.test_func.Assign(PackComparisonOp(regs.stencil_back_func_func));
    } else {
        back.action_stencil_fail.Assign(front.action_stencil_fail);
        back.action_depth_fail.Assign(front.action_depth_fail);
        back.action_depth_pass.Assign(front.action_depth_pass);
        back.test_func.Assign(front.test_func);
    }
    stencil_enable.Assign(regs.stencil_enable);
    depth_write_enable.Assign(regs.depth_write_enabled);
    depth_bounds_enable.Assign(regs.depth_bounds_enable);
    depth_test_enable.Assign(regs.depth_test_enable);
    front_face.Assign(packed_front_face);
    depth_test_func.Assign(PackComparisonOp(regs.depth_test_func));
    cull_face.Assign(PackCullFace(regs.cull_face));
    cull_enable.Assign(regs.cull_test_enabled != 0 ? 1 : 0);
    std::ranges::transform(regs.vertex_array, vertex_strides.begin(), [](const auto& array) {
        return static_cast<u16>(array.stride.Value());
    });
}

size_t FixedPipelineState::Hash() const noexcept {
    const u64 hash = Common::CityHash64(reinterpret_cast<const char*>(this), Size());
    return static_cast<size_t>(hash);
}

bool FixedPipelineState::operator==(const FixedPipelineState& rhs) const noexcept {
    return std::memcmp(this, &rhs, Size()) == 0;
}

u32 FixedPipelineState::PackComparisonOp(Maxwell::ComparisonOp op) noexcept {
    // OpenGL enums go from 0x200 to 0x207 and the others from 1 to 8
    // If we substract 0x200 to OpenGL enums and 1 to the others we get a 0-7 range.
    // Perfect for a hash.
    const u32 value = static_cast<u32>(op);
    return value - (value >= 0x200 ? 0x200 : 1);
}

Maxwell::ComparisonOp FixedPipelineState::UnpackComparisonOp(u32 packed) noexcept {
    // Read PackComparisonOp for the logic behind this.
    return static_cast<Maxwell::ComparisonOp>(packed + 1);
}

u32 FixedPipelineState::PackStencilOp(Maxwell::StencilOp op) noexcept {
    switch (op) {
    case Maxwell::StencilOp::Keep:
    case Maxwell::StencilOp::KeepOGL:
        return 0;
    case Maxwell::StencilOp::Zero:
    case Maxwell::StencilOp::ZeroOGL:
        return 1;
    case Maxwell::StencilOp::Replace:
    case Maxwell::StencilOp::ReplaceOGL:
        return 2;
    case Maxwell::StencilOp::Incr:
    case Maxwell::StencilOp::IncrOGL:
        return 3;
    case Maxwell::StencilOp::Decr:
    case Maxwell::StencilOp::DecrOGL:
        return 4;
    case Maxwell::StencilOp::Invert:
    case Maxwell::StencilOp::InvertOGL:
        return 5;
    case Maxwell::StencilOp::IncrWrap:
    case Maxwell::StencilOp::IncrWrapOGL:
        return 6;
    case Maxwell::StencilOp::DecrWrap:
    case Maxwell::StencilOp::DecrWrapOGL:
        return 7;
    }
    return 0;
}

Maxwell::StencilOp FixedPipelineState::UnpackStencilOp(u32 packed) noexcept {
    static constexpr std::array LUT = {Maxwell::StencilOp::Keep,     Maxwell::StencilOp::Zero,
                                       Maxwell::StencilOp::Replace,  Maxwell::StencilOp::Incr,
                                       Maxwell::StencilOp::Decr,     Maxwell::StencilOp::Invert,
                                       Maxwell::StencilOp::IncrWrap, Maxwell::StencilOp::DecrWrap};
    return LUT[packed];
}

u32 FixedPipelineState::PackCullFace(Maxwell::CullFace cull) noexcept {
    // FrontAndBack is 0x408, by substracting 0x406 in it we get 2.
    // Individual cull faces are in 0x404 and 0x405, substracting 0x404 we get 0 and 1.
    const u32 value = static_cast<u32>(cull);
    return value - (value == 0x408 ? 0x406 : 0x404);
}

Maxwell::CullFace FixedPipelineState::UnpackCullFace(u32 packed) noexcept {
    static constexpr std::array LUT = {Maxwell::CullFace::Front, Maxwell::CullFace::Back,
                                       Maxwell::CullFace::FrontAndBack};
    return LUT[packed];
}

u32 FixedPipelineState::PackFrontFace(Maxwell::FrontFace face) noexcept {
    return static_cast<u32>(face) - 0x900;
}

Maxwell::FrontFace FixedPipelineState::UnpackFrontFace(u32 packed) noexcept {
    return static_cast<Maxwell::FrontFace>(packed + 0x900);
}

u32 FixedPipelineState::PackPolygonMode(Maxwell::PolygonMode mode) noexcept {
    return static_cast<u32>(mode) - 0x1B00;
}

Maxwell::PolygonMode FixedPipelineState::UnpackPolygonMode(u32 packed) noexcept {
    return static_cast<Maxwell::PolygonMode>(packed + 0x1B00);
}

u32 FixedPipelineState::PackLogicOp(Maxwell::LogicOperation op) noexcept {
    return static_cast<u32>(op) - 0x1500;
}

Maxwell::LogicOperation FixedPipelineState::UnpackLogicOp(u32 packed) noexcept {
    return static_cast<Maxwell::LogicOperation>(packed + 0x1500);
}

u32 FixedPipelineState::PackBlendEquation(Maxwell::Blend::Equation equation) noexcept {
    switch (equation) {
    case Maxwell::Blend::Equation::Add:
    case Maxwell::Blend::Equation::AddGL:
        return 0;
    case Maxwell::Blend::Equation::Subtract:
    case Maxwell::Blend::Equation::SubtractGL:
        return 1;
    case Maxwell::Blend::Equation::ReverseSubtract:
    case Maxwell::Blend::Equation::ReverseSubtractGL:
        return 2;
    case Maxwell::Blend::Equation::Min:
    case Maxwell::Blend::Equation::MinGL:
        return 3;
    case Maxwell::Blend::Equation::Max:
    case Maxwell::Blend::Equation::MaxGL:
        return 4;
    }
    return 0;
}

Maxwell::Blend::Equation FixedPipelineState::UnpackBlendEquation(u32 packed) noexcept {
    static constexpr std::array LUT = {
        Maxwell::Blend::Equation::Add, Maxwell::Blend::Equation::Subtract,
        Maxwell::Blend::Equation::ReverseSubtract, Maxwell::Blend::Equation::Min,
        Maxwell::Blend::Equation::Max};
    return LUT[packed];
}

u32 FixedPipelineState::PackBlendFactor(Maxwell::Blend::Factor factor) noexcept {
    switch (factor) {
    case Maxwell::Blend::Factor::Zero:
    case Maxwell::Blend::Factor::ZeroGL:
        return 0;
    case Maxwell::Blend::Factor::One:
    case Maxwell::Blend::Factor::OneGL:
        return 1;
    case Maxwell::Blend::Factor::SourceColor:
    case Maxwell::Blend::Factor::SourceColorGL:
        return 2;
    case Maxwell::Blend::Factor::OneMinusSourceColor:
    case Maxwell::Blend::Factor::OneMinusSourceColorGL:
        return 3;
    case Maxwell::Blend::Factor::SourceAlpha:
    case Maxwell::Blend::Factor::SourceAlphaGL:
        return 4;
    case Maxwell::Blend::Factor::OneMinusSourceAlpha:
    case Maxwell::Blend::Factor::OneMinusSourceAlphaGL:
        return 5;
    case Maxwell::Blend::Factor::DestAlpha:
    case Maxwell::Blend::Factor::DestAlphaGL:
        return 6;
    case Maxwell::Blend::Factor::OneMinusDestAlpha:
    case Maxwell::Blend::Factor::OneMinusDestAlphaGL:
        return 7;
    case Maxwell::Blend::Factor::DestColor:
    case Maxwell::Blend::Factor::DestColorGL:
        return 8;
    case Maxwell::Blend::Factor::OneMinusDestColor:
    case Maxwell::Blend::Factor::OneMinusDestColorGL:
        return 9;
    case Maxwell::Blend::Factor::SourceAlphaSaturate:
    case Maxwell::Blend::Factor::SourceAlphaSaturateGL:
        return 10;
    case Maxwell::Blend::Factor::Source1Color:
    case Maxwell::Blend::Factor::Source1ColorGL:
        return 11;
    case Maxwell::Blend::Factor::OneMinusSource1Color:
    case Maxwell::Blend::Factor::OneMinusSource1ColorGL:
        return 12;
    case Maxwell::Blend::Factor::Source1Alpha:
    case Maxwell::Blend::Factor::Source1AlphaGL:
        return 13;
    case Maxwell::Blend::Factor::OneMinusSource1Alpha:
    case Maxwell::Blend::Factor::OneMinusSource1AlphaGL:
        return 14;
    case Maxwell::Blend::Factor::ConstantColor:
    case Maxwell::Blend::Factor::ConstantColorGL:
        return 15;
    case Maxwell::Blend::Factor::OneMinusConstantColor:
    case Maxwell::Blend::Factor::OneMinusConstantColorGL:
        return 16;
    case Maxwell::Blend::Factor::ConstantAlpha:
    case Maxwell::Blend::Factor::ConstantAlphaGL:
        return 17;
    case Maxwell::Blend::Factor::OneMinusConstantAlpha:
    case Maxwell::Blend::Factor::OneMinusConstantAlphaGL:
        return 18;
    }
    return 0;
}

Maxwell::Blend::Factor FixedPipelineState::UnpackBlendFactor(u32 packed) noexcept {
    static constexpr std::array LUT = {
        Maxwell::Blend::Factor::Zero,
        Maxwell::Blend::Factor::One,
        Maxwell::Blend::Factor::SourceColor,
        Maxwell::Blend::Factor::OneMinusSourceColor,
        Maxwell::Blend::Factor::SourceAlpha,
        Maxwell::Blend::Factor::OneMinusSourceAlpha,
        Maxwell::Blend::Factor::DestAlpha,
        Maxwell::Blend::Factor::OneMinusDestAlpha,
        Maxwell::Blend::Factor::DestColor,
        Maxwell::Blend::Factor::OneMinusDestColor,
        Maxwell::Blend::Factor::SourceAlphaSaturate,
        Maxwell::Blend::Factor::Source1Color,
        Maxwell::Blend::Factor::OneMinusSource1Color,
        Maxwell::Blend::Factor::Source1Alpha,
        Maxwell::Blend::Factor::OneMinusSource1Alpha,
        Maxwell::Blend::Factor::ConstantColor,
        Maxwell::Blend::Factor::OneMinusConstantColor,
        Maxwell::Blend::Factor::ConstantAlpha,
        Maxwell::Blend::Factor::OneMinusConstantAlpha,
    };
    return LUT[packed];
}

} // namespace Vulkan
