//! This example illustrates scrolling in Bevy UI.

use games::*;

fn main() {
    let mut app = App::new();
    app.add_plugins(BaseGamePlugin::default())
        .add_systems(Startup, (setup_list, setup_nav_tree))
        .add_systems(Update, run_tree.run_if(any_component_changed::<NavTree>));
    app.run();
}

fn setup_list(mut commands: Commands) {
    // Scrolling list
    commands
        .spawn((
            Node {
                flex_direction: FlexDirection::Column,
                // If height is not set, we need both align_self: Stetch and overflow: scroll()
                height: Val::Percent(50.0),
                // align_self: AlignSelf::Stretch,
                overflow: Overflow::scroll(),
                ..default()
            },
            BackgroundColor(RED.into()),
        ))
        .with_children(|parent| {
            // List items
            (0..250).for_each(|i| {
                parent.spawn(Text(format!("Item {i}")));
            });
        })
        .observe(scroll);
}

fn setup_nav_tree(mut commands: Commands) {
    // Nav Tree
    commands
        .spawn((
            Node {
                position_type: PositionType::Absolute,
                right: Val::Px(0.0),
                width: Val::Px(100.0),
                height: Val::Px(100.0),
                ..default()
            },
            BackgroundColor(RED.into()),
            NavTree::Closed,
        ))
        .with_children(|parent| {
            parent
                .spawn((
                    Node {
                        position_type: PositionType::Absolute,
                        right: Val::Px(100.0),
                        width: Val::Px(100.0),
                        height: Val::Px(100.0),
                        ..default()
                    },
                    BackgroundColor(ORANGE.into()),
                    NavTree::Closed,
                ))
                .with_children(|parent| {
                    parent.spawn((
                        Node {
                            position_type: PositionType::Absolute,
                            right: Val::Px(100.0),
                            width: Val::Px(100.0),
                            height: Val::Px(100.0),
                            ..default()
                        },
                        BackgroundColor(YELLOW.into()),
                        NavTree::Closed,
                    ));
                });
        });
}

fn run_tree(
    q: Query<(Entity, &NavTree), Changed<NavTree>>,
    children: Query<&Children>,
    mut query: Query<(&ChildOf, &mut Visibility)>,
) {
    q.iter().for_each(|(e, nav)| {
        // todo!("Clean this code up please!");
        match nav {
            NavTree::Open => children.iter_descendants(e).for_each(|child| {
                let (co, mut v) = query.get_mut(child).unwrap();
                if ChildOf(e) == *co {
                    *v = Visibility::Inherited;
                }
            }),
            NavTree::Closed => children.iter_descendants(e).for_each(|child| {
                let (co, mut v) = query.get_mut(child).unwrap();
                if ChildOf(e) == *co {
                    *v = Visibility::Hidden;
                }
            }),
        }
    });
}