#include "Plot.hpp"
#include "Renderable_Adapter.hpp"
#include <asio/co_spawn.hpp>
#include <asio/error_code.hpp>
#include <asio/experimental/concurrent_channel.hpp>
#include <asio/redirect_error.hpp>
#include <asio/strand.hpp>
#include <asio/use_awaitable.hpp>
#include <render_2D/plottable/Plottables.hpp>
#include <render_3D/Render_3D.hpp>
#include <algorithm>
#include <array>
#include <atomic>
#include <cmath>
#include <cstring>
#include <mutex>
#include <stdexcept>
#include <tuple>
#include <unordered_map>
#include <utility>
#include <variant>
#include <vector>

namespace aethera::web {
namespace {
using namespace render_2d;
using namespace render_3d;
using Scene_2D = Impl<Render_Scene_2D>;
using Scene_3D = Impl<Render_Scene_3D>;
using Frequency_Axis_Object = Impl<Frequency_Axis>;
using Numeric_Axis_Object = Impl<Numeric_Axis>;
using Time_Axis_Object = Impl<Time_Axis>;

template <typename Integer>
void append_binary(std::string& output, Integer value) {
    const auto start = output.size();
    output.resize(start + sizeof(Integer));
    std::memcpy(output.data() + start, &value, sizeof(Integer));
}

std::string encode_frame(Image_View image, std::uint64_t sequence) {
    std::string output;
    output.reserve(24 + static_cast<std::size_t>(image.width) * image.height * 4);
    append_binary(output, std::uint32_t{0x41544852});
    append_binary(output, std::uint16_t{1});
    append_binary(output, std::uint16_t{});
    append_binary(output, static_cast<std::uint32_t>(image.width));
    append_binary(output, static_cast<std::uint32_t>(image.height));
    append_binary(output, sequence);
    for (int y = 0; y < image.height; ++y) {
        const auto* row = reinterpret_cast<const std::uint8_t*>(
            image.data + static_cast<std::ptrdiff_t>(y) * image.stride);
        for (int x = 0; x < image.width; ++x) {
            const auto* pixel = row + x * 4;
            output.push_back(static_cast<char>(pixel[2]));
            output.push_back(static_cast<char>(pixel[1]));
            output.push_back(static_cast<char>(pixel[0]));
            output.push_back(static_cast<char>(pixel[3]));
        }
    }
    return output;
}

std::string encode_frame(const Pixel_Frame& frame, std::uint64_t sequence) {
    std::string output;
    output.reserve(24 + frame.rgba8.size());
    append_binary(output, std::uint32_t{0x41544852});
    append_binary(output, std::uint16_t{1});
    append_binary(output, std::uint16_t{});
    append_binary(output, frame.extent.width);
    append_binary(output, frame.extent.height);
    append_binary(output, sequence);
    output.append(reinterpret_cast<const char*>(frame.rgba8.data()), frame.rgba8.size());
    return output;
}

struct Schema_Query { Plot::Json_Handler handler; };
struct Prop_Write {
    std::string key;
    nlohmann::json value;
    Plot::Json_Handler handler;
};
using Plot_Input = std::variant<Plot_Event, Schema_Query, Prop_Write>;

template <typename... Owned_Objects>
class Scene_View_Model final : public Plot::Scene_View {
public:
    Scene_View_Model(std::unique_ptr<detail::Renderable_Descriptor> value_descriptor,
                     std::function<void(const Plot_Event&)> value_update,
                     Owned_Objects... owned_objects)
        : descriptor(std::move(value_descriptor)),
          update_scene(std::move(value_update)),
          objects(std::move(owned_objects)...) {}

    nlohmann::json schema() const override { return descriptor->schema(); }
    nlohmann::json write_prop(std::string_view key, const nlohmann::json& value) override {
        return descriptor->write_prop(key, value);
    }
    void update(const Plot_Event& event) override { update_scene(event); }

private:
    std::unique_ptr<detail::Renderable_Descriptor> descriptor;
    std::function<void(const Plot_Event&)> update_scene;
    std::tuple<Owned_Objects...> objects;
};

template <auto Member, structive::Fixed_String Key, structive::Fixed_String Description>
using Prop_Field = detail::Prop_Field<Member, Key, Description>;

template <typename Definition, auto Member, structive::Fixed_String Key, structive::Fixed_String Description>
using State_Field = detail::State_Field<typename Definition::Base_Tag, Member, Key, Description>;

template <typename... Fields, typename Object, typename... Owned_Objects>
std::unique_ptr<Plot::Scene_View> make_scene_view(
    Object& object,
    std::function<void(const Plot_Event&)> update,
    Owned_Objects&&... owned_objects) {
    using Definition = typename Object::Attached_Object;
    using Tag = typename Definition::Base_Tag;
    using State = typename Definition::State;
    using Adapter = detail::Renderable_Adapter<Object, Fields...,
        detail::State_Field<Tag, &State::prepare_dirty, "prepare_dirty", "Whether source changes require the prepare stage to run again.">,
        detail::State_Field<Tag, &State::paint_dirty, "paint_dirty", "Whether prepared visual data requires the paint stage to run again.">,
        detail::State_Field<Tag, &State::prepare_executed, "prepare_executed", "Whether the prepare stage executed during the latest scene cycle.">,
        detail::State_Field<Tag, &State::paint_executed, "paint_executed", "Whether the paint stage executed during the latest scene cycle.">,
        detail::State_Field<Tag, &State::prepare_graph_rebuilt, "prepare_graph_rebuilt", "Whether the prepare task graph was rebuilt during the latest cycle.">,
        detail::State_Field<Tag, &State::paint_graph_rebuilt, "paint_graph_rebuilt", "Whether the paint task graph was rebuilt during the latest cycle.">,
        detail::State_Field<Tag, &State::prepare_task_count, "prepare_task_count", "Number of tasks in the current prepare execution graph.">,
        detail::State_Field<Tag, &State::paint_task_count, "paint_task_count", "Number of tasks in the current paint execution graph.">,
        detail::State_Field<Tag, &State::prepare_execution_time_ns, "prepare_execution_time_ns", "Measured prepare-stage execution time in nanoseconds.">,
        detail::State_Field<Tag, &State::paint_execution_time_ns, "paint_execution_time_ns", "Measured paint-stage execution time in nanoseconds.">>;
    return std::make_unique<Scene_View_Model<std::remove_cvref_t<Owned_Objects>...>>(
        detail::make_renderable_descriptor(Adapter{object}),
        std::move(update),
        std::forward<Owned_Objects>(owned_objects)...);
}

Frequency_Axis_Object::Builder frequency_axis_builder(Size canvas) {
    Frequency_Axis_Object::Builder builder;
    builder
        .set(&Abs_Axis::Prop::orientation, Axis_Orientation::horizontal)
        .set(&Abs_Axis::Prop::position, Point_F{64.0, 370.0})
        .set(&Abs_Axis::Prop::pixel_length, 620.0)
        .set(&Abs_Axis::Prop::canvas_size, canvas)
        .set(&Numeric_Axis::Prop::coordinate_range, Axis_Range{0.0, 100.0});
    return builder;
}

Numeric_Axis_Object::Builder numeric_axis_builder(
    Axis_Orientation orientation, Point_F position, Axis_Pixel_Length length,
    Axis_Range range, Size canvas) {
    Numeric_Axis_Object::Builder builder;
    builder
        .set(&Abs_Axis::Prop::orientation, orientation)
        .set(&Abs_Axis::Prop::position, position)
        .set(&Abs_Axis::Prop::pixel_length, length)
        .set(&Abs_Axis::Prop::canvas_size, canvas)
        .set(&Numeric_Axis::Prop::coordinate_range, range);
    return builder;
}

Time_Axis_Object::Builder time_axis_builder(
    Axis_Orientation orientation, Point_F position, Axis_Pixel_Length length, Size canvas) {
    Time_Axis_Object::Builder builder;
    builder
        .set(&Abs_Axis::Prop::orientation, orientation)
        .set(&Abs_Axis::Prop::position, position)
        .set(&Abs_Axis::Prop::pixel_length, length)
        .set(&Abs_Axis::Prop::canvas_size, canvas);
    return builder;
}

template <typename... Axes>
void resize_axes(Size viewport, Axes*... axes) {
    (axes->template set<&Abs_Axis::Prop::canvas_size>(viewport), ...);
}

}

std::shared_ptr<Plot> make_spectrum_plot(asio::any_io_executor executor) {
        constexpr Size canvas{720, 420};
        auto frequency = *frequency_axis_builder(canvas).build();
        auto vertical = *numeric_axis_builder(
            Axis_Orientation::vertical, {64.0, 370.0}, -320.0, {-110.0, 0.0}, canvas).build();
        Impl<Spectrum>::Builder spectrum_builder(frequency.get(), vertical.get());
        spectrum_builder.set(&Spectrum::Prop::frequency_range, Axis_Range{0.0, 100.0})
            .set(&Spectrum::Prop::max_hold_visible, true);
        auto spectrum = *spectrum_builder.build();
        Scene_2D::Builder scene_builder;
        scene_builder.set(&Render_Scene_2D::Prop::viewport, canvas)
            .set(&Render_Scene_2D::Prop::background, Color{7, 13, 24, 255})
            .set(&Render_Scene_2D::Prop::view_active, true);
        scene_builder.add_renderable(spectrum.get());
        auto scene = *scene_builder.build();
        auto update = [raw = spectrum.get(), frequency = frequency.get(), vertical = vertical.get()](const Plot_Event& event) {
            resize_axes({static_cast<int>(event.width), static_cast<int>(event.height)}, frequency, vertical);
            std::array<double, 256> samples{};
            for (std::size_t i = 0; i < samples.size(); ++i) {
                const double x = static_cast<double>(i) / samples.size();
                samples[i] = -92.0 + 54.0 * std::exp(-180.0 * std::pow(x - 0.28 - 0.03 * std::sin(event.time_milliseconds * 0.001), 2.0))
                    + 42.0 * std::exp(-260.0 * std::pow(x - 0.68, 2.0))
                    + 2.5 * std::sin(i * 0.31 + event.time_milliseconds * 0.004);
            }
            raw->update_samples(samples);
        };
        auto view = make_scene_view<
            Prop_Field<&Spectrum::Prop::center_frequency, "center_frequency", "Frequency placed at the visual center of the spectrum axis.">,
            Prop_Field<&Spectrum::Prop::partition_count, "partition_count", "Number of partitions used to prepare and render spectrum samples.">,
            Prop_Field<&Spectrum::Prop::max_hold_visible, "max_hold_visible", "Shows the accumulated maximum-hold spectrum curve when enabled.">,
            Prop_Field<&Spectrum::Prop::min_hold_visible, "min_hold_visible", "Shows the accumulated minimum-hold spectrum curve when enabled.">,
            Prop_Field<&Spectrum::Prop::max_marker_visible, "max_marker_visible", "Displays the marker attached to the strongest visible sample.">,
            Prop_Field<&Spectrum::Prop::min_marker_visible, "min_marker_visible", "Displays the marker attached to the weakest visible sample.">,
            Prop_Field<&Spectrum::Prop::sweep_region_visible, "sweep_region_visible", "Highlights the configured sweep-frequency interval on the plot.">,
            Prop_Field<&Spectrum::Prop::visible_range_only, "visible_range_only", "Restricts sample preparation to the frequency range currently visible on the axis.">,
            Prop_Field<&Spectrum::Prop::frequency_range, "frequency_range", "Maps the complete input sample span onto frequency coordinates.">,
            Prop_Field<&Spectrum::Prop::sweep_frequency_range, "sweep_frequency_range", "Defines the frequency interval rendered as the sweep region.">,
            Prop_Field<&Spectrum::Prop::partition_mode, "partition_mode", "Selects how samples are divided between preparation tasks.">,
            Prop_Field<&Spectrum::Prop::interpolation_mode, "interpolation_mode", "Selects the interpolation algorithm used between adjacent spectrum samples.">,
            Prop_Field<&Spectrum::Prop::max_brush, "max_brush", "Fill brush used for the maximum-hold area.">,
            Prop_Field<&Spectrum::Prop::current_brush, "current_brush", "Fill brush used for the current spectrum area.">,
            Prop_Field<&Spectrum::Prop::min_brush, "min_brush", "Fill brush used for the minimum-hold area.">,
            Prop_Field<&Spectrum::Prop::max_pen, "max_pen", "Stroke style used for the maximum-hold curve.">,
            Prop_Field<&Spectrum::Prop::current_pen, "current_pen", "Stroke style used for the current spectrum curve.">,
            Prop_Field<&Spectrum::Prop::min_pen, "min_pen", "Stroke style used for the minimum-hold curve.">,
            Prop_Field<&Spectrum::Prop::selected_marker_pen, "selected_marker_pen", "Stroke style used to emphasize the currently selected marker.">,
            Prop_Field<&Spectrum::Prop::marker_pen, "marker_pen", "Default stroke style used for unselected spectrum markers.">,
            Prop_Field<&Spectrum::Prop::middle_frequency_pen, "middle_frequency_pen", "Stroke style used for the center-frequency indicator.">,
            Prop_Field<&Spectrum::Prop::sweep_region_brush, "sweep_region_brush", "Fill brush used to highlight the sweep-frequency interval.">,
            Prop_Field<&Spectrum::Prop::custom_markers, "custom_markers", "User-defined marker positions and presentation data.">,
            Prop_Field<&Spectrum::Prop::selected_marker, "selected_marker", "Index of the custom marker currently selected for interaction.">,
            State_Field<Spectrum, &Spectrum::State::sample_count, "sample_count", "Number of input spectrum samples available in the latest update.">,
            State_Field<Spectrum, &Spectrum::State::rendered_point_count, "rendered_point_count", "Number of curve points emitted by the latest render preparation.">,
            State_Field<Spectrum, &Spectrum::State::selectable_marker_count, "selectable_marker_count", "Number of markers currently eligible for selection.">>(
                *spectrum, std::move(update), std::move(frequency), std::move(vertical), std::move(spectrum));
        return std::make_shared<Plot>(std::move(executor), std::move(scene), std::move(view));
}

std::shared_ptr<Plot> make_frequency_trace_plot(asio::any_io_executor executor) {
        constexpr Size canvas{720, 420};
        auto time = *time_axis_builder(
            Axis_Orientation::horizontal, {64.0, 370.0}, 620.0, canvas).build();
        auto vertical = *numeric_axis_builder(
            Axis_Orientation::vertical, {64.0, 370.0}, -320.0, {-1.2, 1.2}, canvas).build();
        auto trace = *Impl<Frequency_Trace>::Builder(time.get(), vertical.get()).build();
        Scene_2D::Builder scene_builder;
        scene_builder.set(&Render_Scene_2D::Prop::viewport, canvas)
            .set(&Render_Scene_2D::Prop::background, Color{7, 13, 24, 255})
            .set(&Render_Scene_2D::Prop::view_active, true);
        scene_builder.add_renderable(trace.get());
        auto scene = *scene_builder.build();
        auto update = [raw = trace.get(), time = time.get(), vertical = vertical.get(), tick = std::uint64_t{}](const Plot_Event& event) mutable {
            resize_axes({static_cast<int>(event.width), static_cast<int>(event.height)}, time, vertical);
            raw->append_sample(tick++, std::sin(event.time_milliseconds * 0.0025) * 0.8
                + std::sin(event.time_milliseconds * 0.0007) * 0.2);
        };
        auto view = make_scene_view<
            Prop_Field<&Frequency_Trace::Prop::partition_count, "partition_count", "Number of partitions used to prepare the time-ordered trace.">,
            Prop_Field<&Frequency_Trace::Prop::pen, "pen", "Stroke style used to draw the frequency trace.">,
            Prop_Field<&Frequency_Trace::Prop::partition_mode, "partition_mode", "Selects how trace samples are divided between preparation tasks.">,
            Prop_Field<&Frequency_Trace::Prop::samples, "samples", "Complete time-ordered collection of frequency trace samples.">,
            State_Field<Frequency_Trace, &Frequency_Trace::State::sample_count, "sample_count", "Number of samples retained by the current trace.">,
            State_Field<Frequency_Trace, &Frequency_Trace::State::rendered_point_count, "rendered_point_count", "Number of points emitted for the latest trace frame.">>(
                *trace, std::move(update), std::move(time), std::move(vertical), std::move(trace));
        return std::make_shared<Plot>(std::move(executor), std::move(scene), std::move(view));
}

std::shared_ptr<Plot> make_sweep_spectrum_plot(asio::any_io_executor executor) {
        constexpr Size canvas{720, 420};
        auto frequency = *frequency_axis_builder(canvas).build();
        auto vertical = *numeric_axis_builder(
            Axis_Orientation::vertical, {64.0, 370.0}, -320.0, {-110.0, 0.0}, canvas).build();
        Impl<Sweep_Spectrum>::Builder sweep_builder(frequency.get(), vertical.get());
        sweep_builder.set(&Sweep_Spectrum::Prop::frequency_range, Axis_Range{0.0, 100.0});
        auto sweep = *sweep_builder.build();
        Scene_2D::Builder scene_builder;
        scene_builder.set(&Render_Scene_2D::Prop::viewport, canvas)
            .set(&Render_Scene_2D::Prop::background, Color{7, 13, 24, 255})
            .set(&Render_Scene_2D::Prop::view_active, true);
        scene_builder.add_renderable(sweep.get());
        auto scene = *scene_builder.build();
        auto update = [raw = sweep.get(), frequency = frequency.get(), vertical = vertical.get()](const Plot_Event& event) {
            resize_axes({static_cast<int>(event.width), static_cast<int>(event.height)}, frequency, vertical);
            std::array<double, 64> values{};
            for (std::size_t i = 0; i < values.size(); ++i)
                values[i] = -90.0 + 35.0 * std::sin(i * 0.08 + event.time_milliseconds * 0.002);
            raw->append_block(values);
        };
        auto view = make_scene_view<
            Prop_Field<&Sweep_Spectrum::Prop::bins_per_block, "bins_per_block", "Number of frequency bins stored in each incoming sweep block.">,
            Prop_Field<&Sweep_Spectrum::Prop::block_count, "block_count", "Number of blocks required to compose one complete sweep.">,
            Prop_Field<&Sweep_Spectrum::Prop::partition_count, "partition_count", "Number of partitions used during sweep preparation.">,
            Prop_Field<&Sweep_Spectrum::Prop::visible_range_only, "visible_range_only", "Restricts preparation to the frequency interval visible on the axis.">,
            Prop_Field<&Sweep_Spectrum::Prop::frequency_range, "frequency_range", "Maps the complete sweep span onto frequency coordinates.">,
            Prop_Field<&Sweep_Spectrum::Prop::partition_mode, "partition_mode", "Selects how sweep blocks are divided between preparation tasks.">,
            Prop_Field<&Sweep_Spectrum::Prop::pen, "pen", "Stroke style used for the completed sweep curve.">,
            Prop_Field<&Sweep_Spectrum::Prop::current_frequency_pen, "current_frequency_pen", "Stroke style used for the current sweep-frequency indicator.">,
            Prop_Field<&Sweep_Spectrum::Prop::interpolation_mode, "interpolation_mode", "Selects interpolation between adjacent sweep bins.">,
            Prop_Field<&Sweep_Spectrum::Prop::blocks, "blocks", "Current collection of incremental sweep blocks.">,
            State_Field<Sweep_Spectrum, &Sweep_Spectrum::State::stored_block_count, "stored_block_count", "Number of sweep blocks currently retained.">,
            State_Field<Sweep_Spectrum, &Sweep_Spectrum::State::stored_point_count, "stored_point_count", "Total number of frequency points retained across all blocks.">,
            State_Field<Sweep_Spectrum, &Sweep_Spectrum::State::rendered_point_count, "rendered_point_count", "Number of points emitted for the latest sweep frame.">>(
                *sweep, std::move(update), std::move(frequency), std::move(vertical), std::move(sweep));
        return std::make_shared<Plot>(std::move(executor), std::move(scene), std::move(view));
}

std::shared_ptr<Plot> make_afterglow_plot(asio::any_io_executor executor) {
        constexpr Size canvas{720, 420};
        auto frequency = *frequency_axis_builder(canvas).build();
        auto vertical = *numeric_axis_builder(
            Axis_Orientation::vertical, {64.0, 370.0}, -320.0, {-110.0, 0.0}, canvas).build();
        Impl<Afterglow>::Builder afterglow_builder(frequency.get(), vertical.get());
        afterglow_builder.set(&Afterglow::Prop::frequency_range, Axis_Range{0.0, 100.0})
            .set(&Afterglow::Prop::power_range, Axis_Range{-110.0, 0.0})
            .set(&Afterglow::Prop::power_point_size, 96);
        auto afterglow = *afterglow_builder.build();
        Scene_2D::Builder scene_builder;
        scene_builder.set(&Render_Scene_2D::Prop::viewport, canvas)
            .set(&Render_Scene_2D::Prop::background, Color{7, 13, 24, 255})
            .set(&Render_Scene_2D::Prop::view_active, true);
        scene_builder.add_renderable(afterglow.get());
        auto scene = *scene_builder.build();
        auto update = [raw = afterglow.get(), frequency = frequency.get(), vertical = vertical.get()](const Plot_Event& event) {
            resize_axes({static_cast<int>(event.width), static_cast<int>(event.height)}, frequency, vertical);
            std::array<double, 192> values{};
            for (std::size_t i = 0; i < values.size(); ++i)
                values[i] = -95.0 + 62.0 * std::exp(-220.0 * std::pow(
                    static_cast<double>(i) / values.size() - 0.5
                    - 0.18 * std::sin(event.time_milliseconds * 0.0008), 2.0));
            raw->append_spectrum(values);
        };
        auto view = make_scene_view<
            Prop_Field<&Afterglow::Prop::frequency_point_size, "frequency_point_size", "Number of frequency cells allocated across each afterglow row.">,
            Prop_Field<&Afterglow::Prop::power_point_size, "power_point_size", "Number of power cells allocated along the vertical afterglow range.">,
            Prop_Field<&Afterglow::Prop::partition_count, "partition_count", "Number of partitions used to prepare afterglow history.">,
            Prop_Field<&Afterglow::Prop::interpolate, "interpolate", "Enables interpolation when mapping samples into the afterglow grid.">,
            Prop_Field<&Afterglow::Prop::attenuation_rate, "attenuation_rate", "Controls how quickly historical energy fades between updates.">,
            Prop_Field<&Afterglow::Prop::frequency_range, "frequency_range", "Maps input samples onto the afterglow frequency axis.">,
            Prop_Field<&Afterglow::Prop::power_range, "power_range", "Defines the minimum and maximum power represented by the color grid.">,
            Prop_Field<&Afterglow::Prop::partition_mode, "partition_mode", "Selects how afterglow cells are divided between preparation tasks.">,
            Prop_Field<&Afterglow::Prop::color_map, "color_map", "Maps accumulated energy values to rendered colors.">,
            Prop_Field<&Afterglow::Prop::spectra, "spectra", "Spectrum history currently retained for afterglow rendering.">,
            State_Field<Afterglow, &Afterglow::State::history_count, "history_count", "Number of spectrum frames retained in afterglow history.">,
            State_Field<Afterglow, &Afterglow::State::latest_spectrum_point_count, "latest_spectrum_point_count", "Number of samples in the most recently appended spectrum.">,
            State_Field<Afterglow, &Afterglow::State::rendered_cell_count, "rendered_cell_count", "Number of colored cells emitted for the latest frame.">>(
                *afterglow, std::move(update), std::move(frequency), std::move(vertical), std::move(afterglow));
        return std::make_shared<Plot>(std::move(executor), std::move(scene), std::move(view));
}

std::shared_ptr<Plot> make_waterfall_plot(asio::any_io_executor executor) {
        constexpr Size canvas{720, 420};
        auto frequency = *frequency_axis_builder(canvas).build();
        auto time = *time_axis_builder(
            Axis_Orientation::vertical, {64.0, 370.0}, -320.0, canvas).build();
        Impl<Waterfall>::Builder waterfall_builder(frequency.get(), time.get());
        waterfall_builder.set(&Waterfall::Prop::frequency_range, Axis_Range{0.0, 100.0})
            .set(&Waterfall::Prop::power_range, Axis_Range{-110.0, 0.0});
        auto waterfall = *waterfall_builder.build();
        Scene_2D::Builder scene_builder;
        scene_builder.set(&Render_Scene_2D::Prop::viewport, canvas)
            .set(&Render_Scene_2D::Prop::background, Color{7, 13, 24, 255})
            .set(&Render_Scene_2D::Prop::view_active, true);
        scene_builder.add_renderable(waterfall.get());
        auto scene = *scene_builder.build();
        auto update = [raw = waterfall.get(), frequency = frequency.get(), time = time.get(), tick = std::uint64_t{}](const Plot_Event& event) mutable {
            resize_axes({static_cast<int>(event.width), static_cast<int>(event.height)}, frequency, time);
            std::array<double, 192> values{};
            for (std::size_t i = 0; i < values.size(); ++i)
                values[i] = -100.0 + 70.0 * std::exp(-240.0 * std::pow(
                    static_cast<double>(i) / values.size() - 0.5
                    - 0.22 * std::sin(event.time_milliseconds * 0.0006), 2.0));
            raw->append_row(tick++, values);
        };
        auto view = make_scene_view<
            Prop_Field<&Waterfall::Prop::tooltip_enabled, "tooltip_enabled", "Enables value inspection tooltips over waterfall cells.">,
            Prop_Field<&Waterfall::Prop::tooltip_font, "tooltip_font", "Font used to render waterfall tooltip text.">,
            Prop_Field<&Waterfall::Prop::tooltip_text_pen, "tooltip_text_pen", "Pen used to draw tooltip text and its foreground color.">,
            Prop_Field<&Waterfall::Prop::tooltip_background_brush, "tooltip_background_brush", "Brush used to fill the tooltip background panel.">,
            Prop_Field<&Waterfall::Prop::frequency_bin_count, "frequency_bin_count", "Number of frequency bins expected in each waterfall row.">,
            Prop_Field<&Waterfall::Prop::partition_count, "partition_count", "Number of partitions used to prepare waterfall cells.">,
            Prop_Field<&Waterfall::Prop::visible_range_only, "visible_range_only", "Restricts preparation to frequencies visible on the current axis.">,
            Prop_Field<&Waterfall::Prop::frequency_range, "frequency_range", "Maps row samples onto waterfall frequency coordinates.">,
            Prop_Field<&Waterfall::Prop::power_range, "power_range", "Defines the power interval mapped through the waterfall color map.">,
            Prop_Field<&Waterfall::Prop::partition_mode, "partition_mode", "Selects how waterfall rows are divided between preparation tasks.">,
            Prop_Field<&Waterfall::Prop::interpolation_mode, "interpolation_mode", "Selects interpolation when samples are mapped to raster cells.">,
            Prop_Field<&Waterfall::Prop::color_map, "color_map", "Maps sample power values to waterfall colors.">,
            Prop_Field<&Waterfall::Prop::rows, "rows", "Time-ordered collection of spectrum rows retained by the waterfall.">,
            State_Field<Waterfall, &Waterfall::State::row_count, "row_count", "Number of waterfall rows currently retained.">,
            State_Field<Waterfall, &Waterfall::State::stored_point_count, "stored_point_count", "Total number of spectrum points retained across all rows.">,
            State_Field<Waterfall, &Waterfall::State::rendered_cell_count, "rendered_cell_count", "Number of raster cells emitted for the latest frame.">>(
                *waterfall, std::move(update), std::move(frequency), std::move(time), std::move(waterfall));
        return std::make_shared<Plot>(std::move(executor), std::move(scene), std::move(view));
}

std::shared_ptr<Plot> make_constellation_plot(asio::any_io_executor executor) {
        constexpr Size canvas{720, 420};
        auto horizontal = *numeric_axis_builder(
            Axis_Orientation::horizontal, {64.0, 370.0}, 620.0, {-1.2, 1.2}, canvas).build();
        auto vertical = *numeric_axis_builder(
            Axis_Orientation::vertical, {64.0, 370.0}, -320.0, {-1.2, 1.2}, canvas).build();
        Impl<Constellation_Diagram>::Builder constellation_builder(horizontal.get(), vertical.get());
        constellation_builder.set(&Constellation_Diagram::Prop::i_range, Axis_Range{-1.2, 1.2})
            .set(&Constellation_Diagram::Prop::q_range, Axis_Range{-1.2, 1.2});
        auto constellation = *constellation_builder.build();
        Scene_2D::Builder scene_builder;
        scene_builder.set(&Render_Scene_2D::Prop::viewport, canvas)
            .set(&Render_Scene_2D::Prop::background, Color{7, 13, 24, 255})
            .set(&Render_Scene_2D::Prop::view_active, true);
        scene_builder.add_renderable(constellation.get());
        auto scene = *scene_builder.build();
        auto update = [raw = constellation.get(), horizontal = horizontal.get(), vertical = vertical.get()](const Plot_Event& event) {
            resize_axes({static_cast<int>(event.width), static_cast<int>(event.height)}, horizontal, vertical);
            const double phase = event.time_milliseconds * 0.003;
            raw->append_point({std::cos(phase) * 0.82 + 0.04 * std::sin(phase * 7.0),
                               std::sin(phase) * 0.82 + 0.04 * std::cos(phase * 5.0)});
        };
        auto view = make_scene_view<
            Prop_Field<&Constellation_Diagram::Prop::point_lifetime_ms, "point_lifetime_ms", "Time in milliseconds that an appended constellation point remains visible.">,
            Prop_Field<&Constellation_Diagram::Prop::type, "type", "Selects the modulation constellation used to generate reference anchors.">,
            Prop_Field<&Constellation_Diagram::Prop::phase_offset_radians, "phase_offset_radians", "Rotates constellation points and anchors by the specified phase angle.">,
            Prop_Field<&Constellation_Diagram::Prop::i_range, "i_range", "Defines the horizontal in-phase coordinate interval.">,
            Prop_Field<&Constellation_Diagram::Prop::q_range, "q_range", "Defines the vertical quadrature coordinate interval.">,
            Prop_Field<&Constellation_Diagram::Prop::point_color, "point_color", "Color used to render received I/Q samples.">,
            Prop_Field<&Constellation_Diagram::Prop::anchor_color, "anchor_color", "Color used to render ideal modulation anchors.">,
            Prop_Field<&Constellation_Diagram::Prop::points, "points", "Current time-stamped collection of received I/Q samples.">,
            State_Field<Constellation_Diagram, &Constellation_Diagram::State::point_count, "point_count", "Number of constellation samples currently retained.">>(
                *constellation, std::move(update), std::move(horizontal), std::move(vertical), std::move(constellation));
        return std::make_shared<Plot>(std::move(executor), std::move(scene), std::move(view));
}

std::shared_ptr<Plot> make_selection_overlay_plot(asio::any_io_executor executor) {
        constexpr Size canvas{720, 420};
        auto horizontal = *numeric_axis_builder(
            Axis_Orientation::horizontal, {64.0, 370.0}, 620.0, {0.0, 100.0}, canvas).build();
        auto vertical = *numeric_axis_builder(
            Axis_Orientation::vertical, {64.0, 370.0}, -320.0, {0.0, 100.0}, canvas).build();
        auto selection = *Impl<Selection_Rectangle_Overlay>::Builder(horizontal.get(), vertical.get()).build();
        Scene_2D::Builder scene_builder;
        scene_builder.set(&Render_Scene_2D::Prop::viewport, canvas)
            .set(&Render_Scene_2D::Prop::background, Color{7, 13, 24, 255})
            .set(&Render_Scene_2D::Prop::view_active, true);
        scene_builder.add_renderable(selection.get());
        auto scene = *scene_builder.build();
        auto update = [horizontal = horizontal.get(), vertical = vertical.get()](const Plot_Event& event) {
            resize_axes({static_cast<int>(event.width), static_cast<int>(event.height)}, horizontal, vertical);
        };
        auto view = make_scene_view<
            Prop_Field<&Selection_Rectangle_Overlay::Prop::label_font, "label_font", "Font used for labels attached to selected regions.">,
            Prop_Field<&Selection_Rectangle_Overlay::Prop::label_pen, "label_pen", "Pen used to draw selected-region label text.">,
            Prop_Field<&Selection_Rectangle_Overlay::Prop::selection_brush, "selection_brush", "Brush used to fill selected rectangular regions.">,
            Prop_Field<&Selection_Rectangle_Overlay::Prop::selection_border_pen, "selection_border_pen", "Pen used to draw selected-region borders.">,
            Prop_Field<&Selection_Rectangle_Overlay::Prop::selected_regions, "selected_regions", "Collection of selected rectangles expressed in axis coordinates.">,
            State_Field<Selection_Rectangle_Overlay,
                        &Selection_Rectangle_Overlay::State::selected_region_count,
                        "selected_region_count",
                        "Number of rectangular regions currently selected.">>(
                *selection, std::move(update), std::move(horizontal), std::move(vertical), std::move(selection));
        return std::make_shared<Plot>(std::move(executor), std::move(scene), std::move(view));
}

struct Plot::Private {
    using Scene = std::variant<std::unique_ptr<Scene_2D>, std::unique_ptr<Scene_3D>>;
    asio::strand<asio::any_io_executor> strand;
    asio::experimental::concurrent_channel<void(asio::error_code, Plot_Input)> inputs;
    Scene scene;
    std::unique_ptr<Scene_View> view;
    std::once_flag start_once;
    std::mutex handlers_mutex;
    std::unordered_map<const void*, Frame_Handler> handlers;
    std::atomic_uint64_t frame_sequence{};

    template <typename Scene_Object>
    Private(asio::any_io_executor executor,
            std::unique_ptr<Scene_Object> value_scene,
            std::unique_ptr<Scene_View> value_view)
        : strand(asio::make_strand(std::move(executor))), inputs(strand, 32),
          scene(std::move(value_scene)), view(std::move(value_view)) {}

    void publish(std::string pixels) {
        std::vector<Frame_Handler> outputs;
        {
            std::lock_guard lock(handlers_mutex);
            outputs.reserve(handlers.size());
            for (const auto& [owner, handler] : handlers) outputs.push_back(handler);
        }
        for (auto& output : outputs) output(pixels);
    }
};

Plot::Plot(asio::any_io_executor executor,
           std::unique_ptr<Scene_2D> scene,
           std::unique_ptr<Scene_View> view)
    : d(std::make_unique<Private>(std::move(executor), std::move(scene), std::move(view))) {}

Plot::Plot(asio::any_io_executor executor,
           std::unique_ptr<Scene_3D> scene,
           std::unique_ptr<Scene_View> view)
    : d(std::make_unique<Private>(std::move(executor), std::move(scene), std::move(view))) {}

Plot::~Plot() { d->inputs.close(); }

void Plot::ensure_started() {
    std::call_once(d->start_once, [this] {
        auto self = shared_from_this();
        if (auto* scene = std::get_if<std::unique_ptr<Scene_2D>>(&d->scene)) {
            (*scene)->set_frame_callback([weak = weak_from_this()](Image_View image) {
                if (auto owner = weak.lock()) {
                    const auto sequence = owner->d->frame_sequence.fetch_add(1, std::memory_order_acq_rel) + 1;
                    owner->d->publish(encode_frame(image, sequence));
                }
            });
        } else {
            std::get<std::unique_ptr<Scene_3D>>(d->scene)->set_frame_callback(
                [weak = weak_from_this()](std::shared_ptr<const Pixel_Frame> frame) {
                    if (auto owner = weak.lock()) {
                        const auto sequence = owner->d->frame_sequence.fetch_add(1, std::memory_order_acq_rel) + 1;
                        owner->d->publish(encode_frame(*frame, sequence));
                    }
                });
        }
        asio::co_spawn(d->strand, [self]() -> asio::awaitable<void> {
            for (;;) {
                asio::error_code error;
                auto input = co_await self->d->inputs.async_receive(
                    asio::redirect_error(asio::use_awaitable, error));
                if (error) co_return;
                if (auto* query = std::get_if<Schema_Query>(&input)) {
                    query->handler(self->d->view->schema());
                    continue;
                }
                if (auto* write = std::get_if<Prop_Write>(&input)) {
                    write->handler(self->d->view->write_prop(write->key, write->value));
                    continue;
                }
                auto event = std::get<Plot_Event>(input);
                event.width = std::clamp(event.width, 160U, 1920U);
                event.height = std::clamp(event.height, 120U, 1080U);
                self->d->view->update(event);
                if (auto* scene = std::get_if<std::unique_ptr<Scene_2D>>(&self->d->scene)) {
                    (*scene)->set<&Render_Scene_2D::Prop::viewport>(
                        Size{static_cast<int>(event.width), static_cast<int>(event.height)});
                    (*scene)->render();
                } else {
                    auto& scene_3d = std::get<std::unique_ptr<Scene_3D>>(self->d->scene);
                    scene_3d->set<&Render_Scene_3D::Prop::viewport>(Extent{event.width, event.height});
                    scene_3d->render();
                }
            }
        }, [](std::exception_ptr exception) {
            if (exception) std::rethrow_exception(exception);
        });
    });
}

void Plot::attach(const void* owner, Frame_Handler handler) {
    ensure_started();
    {
        std::lock_guard lock(d->handlers_mutex);
        d->handlers.insert_or_assign(owner, std::move(handler));
    }
    submit({});
}

void Plot::detach(const void* owner) {
    std::lock_guard lock(d->handlers_mutex);
    d->handlers.erase(owner);
}

void Plot::submit(Plot_Event event) {
    ensure_started();
    static_cast<void>(d->inputs.try_send(asio::error_code{}, Plot_Input{event}));
}

void Plot::async_schema(Json_Handler handler) {
    ensure_started();
    if (!d->inputs.try_send(asio::error_code{}, Plot_Input{Schema_Query{std::move(handler)}}))
        throw std::runtime_error("plot input queue is unavailable");
}

void Plot::async_write_prop(std::string key, nlohmann::json value, Json_Handler handler) {
    ensure_started();
    if (!d->inputs.try_send(asio::error_code{}, Plot_Input{
            Prop_Write{std::move(key), std::move(value), std::move(handler)}}))
        throw std::runtime_error("plot input queue is unavailable");
}

std::shared_ptr<Plot> make_datoviz_point_plot(asio::any_io_executor executor) {
    using Visual_Object = Impl<Point_Visual>;
    auto visual = *Visual_Object::Builder{}.build();
    static_cast<void>(visual->update_items({
        render_3d::Point{.position = {-0.55F, -0.2F, 0.0F}, .color = Color::red_color(), .diameter_px = 24.0F},
        render_3d::Point{.position = {0.0F, 0.5F, 0.0F}, .color = Color::green_color(), .diameter_px = 30.0F},
        render_3d::Point{.position = {0.55F, -0.1F, 0.0F}, .color = Color{42, 120, 255, 255}, .diameter_px = 26.0F}}));
    visual->advance();
    auto scene = *Scene_3D::Builder(visual.get())
        .set(&Render_Scene_3D::Prop::viewport, Extent{720, 420})
        .set(&Render_Scene_3D::Prop::view_active, true)
        .build();
    using Adapter = detail::Renderable_Adapter<Visual_Object,
        detail::Prop_Field<&Point_Visual::Prop::transform, "transform", "World transform applied to every point in the visual.">,
        detail::Prop_Field<&Point_Visual::Prop::visible, "visible", "Controls whether the point visual participates in scene rendering.">,
        detail::Prop_Field<&Point_Visual::Prop::depth_test, "depth_test", "Enables depth testing when point fragments are rendered.">,
        detail::Prop_Field<&Point_Visual::Prop::items, "items", "Complete collection of 3D points submitted to the visual.">,
        detail::State_Field<Point_Visual::Base_Tag, &Point_Visual::State::item_count, "item_count", "Number of point items currently published by the visual.">,
        detail::State_Field<Point_Visual::Base_Tag, &Point_Visual::State::prepared_item_count, "prepared_item_count", "Number of point items prepared for the latest GPU submission.">,
        detail::State_Field<Point_Visual::Base_Tag, &Point_Visual::State::prepared_revision, "prepared_revision", "Property revision represented by the currently prepared GPU data.">>;
    auto view = std::make_unique<Scene_View_Model<decltype(visual)>>(
        detail::make_renderable_descriptor(Adapter{*visual}),
        [](const Plot_Event&) {}, std::move(visual));
    return std::make_shared<Plot>(std::move(executor), std::move(scene), std::move(view));
}
}