use bevy::prelude::*;
use bevy::winit::WinitSettings;

fn main() {
  App::new()
      .add_plugins(DefaultPlugins)
      .insert_resource(WinitSettings::desktop_app())
      .add_startup_system(spawn)
      .run();
}

fn spawn(mut commands: Commands, asset_server: Res<AssetServer>) {
  commands.spawn(Camera2dBundle::default());

  let gap = Val::Px(8.0);

  commands
      .spawn(NodeBundle {
          style: Style {
              flex_direction: FlexDirection::Column,
              size: Size::new(Val::Percent(100.), Val::Percent(100.)),
              gap: Size::all(gap),
              padding: UiRect::all(gap),
              ..Default::default()
          },
          background_color: Color::BLACK.into(),
          ..Default::default()
      })
      .with_children(|parent| {
          for _ in 0..2 {
              parent
                  .spawn(NodeBundle {
                      style: Style {
                          size: Size::new(Val::Percent(100.0), Val::Percent(50.)),
                          gap: Size::all(gap),
                          ..default()
                      },
                      ..default()
                  })
                  .with_children(|parent| {
                      for _ in 0..5 {
                          parent
                              .spawn(NodeBundle {
                                  style: Style {
                                      size: Size::new(Val::Auto, Val::Percent(100.)),
                                      overflow: Overflow::Hidden, // <====
                                      flex_grow: 1.0,
                                      flex_basis: Val::Px(0.),
                                      ..default()
                                  },
                                  background_color: Color::GRAY.into(),
                                  ..default()
                              })
                              .with_children(|parent| {
                                  parent.spawn(NodeBundle {
                                      style: Style {
                                          size: Size::new(Val::Px(150.0), Val::Px(30.0)),
                                          ..default()
                                      },
                                      background_color: Color::ORANGE.into(),
                                      ..default()
                                  });
                              });
                      }
                  });
          }
      });
}