use gooey::value::{Dynamic, MapEach};
use gooey::widget::MakeWidget;
use gooey::{Application, Open, PendingApp, Run};

fn main() -> gooey::Result {
    // To open multiple applications, we need a handle to the application. This
    // starts with the `PendingApp` type.
    let app = PendingApp::default();

    let open_windows = Dynamic::new(0_usize);
    let counter = Dynamic::new(0_usize);

    // We're going to open two windows as part of the app startup process.
    // First, the "main" window that displays some stats about the open windows.
    (&open_windows, &counter)
        .map_each(|(open, counter)| {
            format!(
                "There are {open} other window(s) open. {counter} total windows have been opened"
            )
        })
        .and(open_window_button(&app, &open_windows, &counter))
        .into_rows()
        .centered()
        // The other examples call run() on the widget/window. Since we're
        // opening two windows at the app's startup,
        .open(&app)?;

    // And now let's open our first "clone" window -- the window that clicking
    // the open button on any of the windows will create.
    open_another_window(&app, &open_windows, &counter);

    // Run the application
    app.run()
}

/// Returns a button that invokes `open_another_window` when clicked.
fn open_window_button(
    app: &impl Application,
    open_windows: &Dynamic<usize>,
    counter: &Dynamic<usize>,
) -> impl MakeWidget {
    let app = app.as_app();
    let open_windows = open_windows.clone();
    let counter = counter.clone();
    "Open Another Window".into_button().on_click(move |()| {
        open_another_window(&app, &open_windows, &counter);
    })
}

/// Opens another window that contains a button that opens another window.
fn open_another_window(
    app: &impl Application,
    open_windows: &Dynamic<usize>,
    counter: &Dynamic<usize>,
) {
    let my_number = counter.map_mut(|count| {
        *count += 1;
        *count
    });
    let open_windows = open_windows.clone();
    open_windows.map_mut(|open_windows| *open_windows += 1);
    format!("This is window {my_number}")
        .and(open_window_button(app, &open_windows, counter))
        .into_rows()
        .centered()
        .into_window()
        .on_close(move || open_windows.map_mut(|open_windows| *open_windows -= 1))
        .open(app)
        .expect("error opening another window");
}