nebulus 0.1.25

Low-latency native OpenIPC FPV ground station built with egui
use eframe::egui;
use openipc_core::channel::DEFAULT_LINK_ID;

use crate::{
    app::NebulusApp,
    model::ReceiverState,
    settings::{DEFAULT_CHANNEL, DEFAULT_CHANNEL_OFFSET, MAX_LINK_ID},
};

pub(crate) fn show(app: &mut NebulusApp, ui: &mut egui::Ui) {
    let editable = matches!(app.state, ReceiverState::Idle | ReceiverState::Failed);
    ui.add_enabled_ui(editable, |ui| {
        section(ui, "Receiver", |ui| {
            ui.horizontal(|ui| {
                egui::ComboBox::from_id_salt("usb-device")
                    .selected_text(selected_device_label(app))
                    .width(230.0)
                    .show_ui(ui, |ui| {
                        for device in &app.devices {
                            ui.selectable_value(
                                &mut app.settings.device_id,
                                Some(device.id.clone()),
                                format!("{} ({})", device.label, device.id),
                            );
                        }
                    });
                if ui.button("Refresh").clicked() {
                    app.refresh_devices();
                }
            });
            if app.devices.is_empty() {
                ui.label(
                    egui::RichText::new("No supported USB adapter found")
                        .small()
                        .color(ui.visuals().weak_text_color()),
                );
            }
        });

        section(ui, "Radio", |ui| {
            egui::Grid::new("radio-settings")
                .num_columns(3)
                .spacing([18.0, 8.0])
                .show(ui, |ui| {
                    ui.label("Channel");
                    ui.add(
                        egui::Slider::new(&mut app.settings.channel, 1..=177)
                            .show_value(true)
                            .text(""),
                    );
                    if ui.small_button("Default").clicked() {
                        app.settings.channel = DEFAULT_CHANNEL;
                    }
                    ui.end_row();
                    ui.label("Width");
                    egui::ComboBox::from_id_salt("channel-width")
                        .selected_text(format!("{} MHz", app.settings.channel_width_mhz))
                        .show_ui(ui, |ui| {
                            for width in [5, 10, 20, 40, 80] {
                                ui.selectable_value(
                                    &mut app.settings.channel_width_mhz,
                                    width,
                                    format!("{width} MHz"),
                                );
                            }
                        });
                    ui.label("");
                    ui.end_row();
                    ui.label("Offset");
                    ui.add(
                        egui::Slider::new(&mut app.settings.channel_offset, 0..=4)
                            .show_value(true)
                            .text(""),
                    );
                    if ui.small_button("Default").clicked() {
                        app.settings.channel_offset = DEFAULT_CHANNEL_OFFSET;
                    }
                    ui.end_row();
                    ui.label("Link ID");
                    ui.add(
                        egui::Slider::new(&mut app.settings.link_id, 0..=MAX_LINK_ID)
                            .show_value(true)
                            .custom_formatter(|value, _| format!("0x{:06X}", value as u32))
                            .custom_parser(parse_link_id),
                    );
                    if ui.small_button("Default").clicked() {
                        app.settings.link_id = DEFAULT_LINK_ID;
                    }
                    ui.end_row();
                });
        });

        section(ui, "Link", |ui| {
            ui.checkbox(&mut app.settings.rtp_reorder, "RTP reorder buffer");
            ui.checkbox(&mut app.settings.adaptive_link, "Adaptive link feedback");
            if app.settings.adaptive_link {
                ui.horizontal(|ui| {
                    ui.label("Uplink TX power");
                    ui.add(egui::Slider::new(&mut app.settings.tx_power, 0..=127));
                });
            }
        });

        section(ui, "Receiver key", |ui| {
            ui.horizontal(|ui| {
                if ui.button("Open file").clicked() {
                    app.open_key_file(ui.ctx());
                }
                if ui.button("Use default").clicked() {
                    app.reset_key();
                }
            });
            ui.horizontal(|ui| {
                ui.label(&app.key_name);
                ui.label(
                    egui::RichText::new(format!("{} bytes", app.settings.key_bytes.len()))
                        .small()
                        .color(ui.visuals().weak_text_color()),
                );
            });
            if let Some(error) = &app.key_error {
                ui.colored_label(ui.visuals().error_fg_color, error);
            } else {
                ui.label(
                    egui::RichText::new("You can also drop a gs.key file anywhere on the window")
                        .small()
                        .color(ui.visuals().weak_text_color()),
                );
            }
        });

        section(ui, "Video", |ui| {
            ui.horizontal(|ui| {
                ui.label("Codec preference");
                egui::ComboBox::from_id_salt("codec-preference")
                    .selected_text(app.settings.codec_preference.label())
                    .show_ui(ui, |ui| {
                        for preference in [
                            crate::settings::CodecPreference::Auto,
                            crate::settings::CodecPreference::H264,
                            crate::settings::CodecPreference::H265,
                        ] {
                            ui.selectable_value(
                                &mut app.settings.codec_preference,
                                preference,
                                preference.label(),
                            );
                        }
                    });
            });
            ui.checkbox(&mut app.settings.show_osd, "Link telemetry overlay");
            ui.horizontal(|ui| {
                ui.label("Decoder queue");
                ui.label("3 frames, latest-frame output");
            });
        });

        section(ui, "Advanced", |ui| {
            egui::Grid::new("advanced-settings")
                .num_columns(2)
                .show(ui, |ui| {
                    ui.label("Minimum epoch");
                    ui.add(egui::DragValue::new(&mut app.settings.minimum_epoch));
                    ui.end_row();
                    ui.label("USB transfer size");
                    ui.add(
                        egui::DragValue::new(&mut app.settings.transfer_size)
                            .range(4_096..=1_048_576),
                    );
                    ui.end_row();
                    ui.label("Diagnostic verbosity");
                    egui::ComboBox::from_id_salt("diagnostic-verbosity")
                        .selected_text(app.settings.diagnostic_verbosity.label())
                        .show_ui(ui, |ui| {
                            for verbosity in [
                                crate::settings::DiagnosticVerbosity::Low,
                                crate::settings::DiagnosticVerbosity::Normal,
                                crate::settings::DiagnosticVerbosity::High,
                            ] {
                                ui.selectable_value(
                                    &mut app.settings.diagnostic_verbosity,
                                    verbosity,
                                    verbosity.label(),
                                );
                            }
                        });
                    ui.end_row();
                });
        });
    });
}

fn parse_link_id(value: &str) -> Option<f64> {
    let value = value.trim();
    let parsed = value
        .strip_prefix("0x")
        .or_else(|| value.strip_prefix("0X"))
        .map_or_else(
            || value.parse::<u32>().ok(),
            |hex| u32::from_str_radix(hex, 16).ok(),
        )?;
    (parsed <= MAX_LINK_ID).then_some(f64::from(parsed))
}

fn selected_device_label(app: &NebulusApp) -> String {
    app.settings
        .device_id
        .as_deref()
        .and_then(|id| app.devices.iter().find(|device| device.id == id))
        .map(|device| format!("{} ({})", device.label, device.id))
        .or_else(|| app.settings.device_id.clone())
        .unwrap_or_else(|| "Select an adapter".to_owned())
}

fn section(ui: &mut egui::Ui, title: &str, add: impl FnOnce(&mut egui::Ui)) {
    egui::CollapsingHeader::new(title)
        .default_open(true)
        .show(ui, |ui| {
            ui.add_space(4.0);
            add(ui);
            ui.add_space(8.0);
        });
}

#[cfg(test)]
mod tests {
    use super::parse_link_id;

    #[test]
    fn link_id_parser_accepts_decimal_and_hex() {
        assert_eq!(parse_link_id("7669206"), Some(7_669_206.0));
        assert_eq!(parse_link_id("0x7505D6"), Some(7_669_206.0));
    }

    #[test]
    fn link_id_parser_rejects_values_above_24_bits() {
        assert_eq!(parse_link_id("0x1000000"), None);
    }
}