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use gtk::prelude::{BoxExt, ButtonExt, GtkWindowExt, OrientableExt};
use relm4::{gtk, ComponentParts, ComponentSender, RelmApp, RelmWidgetExt, SimpleComponent};

struct App {
    counter: u8,
}

#[derive(Debug)]
enum Msg {
    Increment,
    Decrement,
}

#[relm4::component]
impl SimpleComponent for App {
    type Init = u8;
    type Input = Msg;
    type Output = ();

    view! {
        gtk::Window {
            set_title: Some("Log example"),
            set_default_size: (300, 100),

            gtk::Box {
                set_orientation: gtk::Orientation::Vertical,
                set_spacing: 5,
                set_margin_all: 5,

                gtk::Button {
                    set_label: "Increment",
                    connect_clicked => Msg::Increment,
                },

                gtk::Button {
                    set_label: "Decrement",
                    connect_clicked => Msg::Decrement,
                },

                gtk::Label {
                    set_margin_all: 5,
                    #[watch]
                    set_label: &format!("Counter: {}", model.counter),
                }
            }
        }
    }

    fn init(
        counter: Self::Init,
        root: &Self::Root,
        sender: ComponentSender<Self>,
    ) -> ComponentParts<Self> {
        let model = App { counter };

        // Insert the macro code generation here
        let widgets = view_output!();

        ComponentParts { model, widgets }
    }

    fn update(&mut self, msg: Self::Input, _sender: ComponentSender<Self>) {
        match msg {
            Msg::Increment => {
                self.counter = self.counter.wrapping_add(1);
            }
            Msg::Decrement => {
                self.counter = self.counter.wrapping_sub(1);
            }
        }
    }
}

fn main() {
    // Show traces to find potential performance bottlenecks, for example
    tracing_subscriber::fmt()
        .with_span_events(tracing_subscriber::fmt::format::FmtSpan::FULL)
        .with_max_level(tracing::Level::TRACE)
        .init();

    tracing::info!("Starting application!");

    let app: RelmApp = RelmApp::new("relm4.example.log");
    app.run::<App>(0);
}