use bevy::{
    color::palettes::css::{BLACK, WHITE},
    prelude::*,
};
use bevy_rapier3d::prelude::*;
use bevy_ui_anchor::{AnchorUiNode, AnchorUiPlugin};

fn main() {
    App::new()
        .insert_resource(ClearColor(Color::srgb(
            0xF9 as f32 / 255.0,
            0xF9 as f32 / 255.0,
            0xFF as f32 / 255.0,
        )))
        .add_plugins((
            DefaultPlugins,
            RapierPhysicsPlugin::<NoUserData>::default(),
            RapierDebugRenderPlugin::default(),
        ))
        .add_plugins(AnchorUiPlugin::<CameraMarker>::new())
        .add_systems(Startup, (setup_graphics, setup_physics))
        .run();
}

#[derive(Component)]
pub struct CameraMarker;

pub fn setup_graphics(mut commands: Commands) {
    commands.spawn((
        CameraMarker,
        Camera3dBundle {
            transform: Transform::from_xyz(-30.0, 30.0, 100.0)
                .looking_at(Vec3::new(0.0, 10.0, 0.0), Vec3::Y),
            ..Default::default()
        },
    ));
}

pub fn setup_physics(mut commands: Commands) {
    /*
     * Ground
     */
    let ground_size = 200.1;
    let ground_height = 0.1;

    commands.spawn((
        TransformBundle::from(Transform::from_xyz(0.0, -ground_height, 0.0)),
        Collider::cuboid(ground_size, ground_height, ground_size),
    ));

    /*
     * Create the cubes
     */
    let num = 3;
    let rad = 3.0;

    let shift = rad * 2.0 + rad;
    let centerx = shift * (num / 2) as f32;
    let centery = shift / 2.0;
    let centerz = shift * (num / 2) as f32;

    let mut offset = -(num as f32) * (rad * 2.0 + rad) * 0.5;
    let mut color = 0;
    let colors = [
        Hsla::hsl(220.0, 1.0, 0.3),
        Hsla::hsl(180.0, 1.0, 0.3),
        Hsla::hsl(260.0, 1.0, 0.7),
    ];

    for j in 0usize..20 {
        for i in 0..num {
            for k in 0usize..num {
                let x = i as f32 * shift - centerx + offset;
                let y = j as f32 * shift + centery + 3.0;
                let z = k as f32 * shift - centerz + offset;
                color += 1;

                let target = commands
                    .spawn((
                        TransformBundle::from(Transform::from_xyz(x, y, z)),
                        RigidBody::Dynamic,
                        Collider::ball(rad),
                        ColliderDebugColor(colors[color % 3]),
                    ))
                    .id();
                commands
                    .spawn((
                        NodeBundle {
                            border_color: BorderColor(BLACK.into()),
                            border_radius: BorderRadius::all(Val::Px(2.)),
                            style: Style {
                                border: UiRect::all(Val::Px(2.)),
                                ..Default::default()
                            },
                            ..Default::default()
                        },
                        Outline::default(),
                        AnchorUiNode {
                            target: bevy_ui_anchor::AnchorTarget::Entity(target),
                            anchorwidth: bevy_ui_anchor::HorizontalAnchor::Right,
                            anchorheight: bevy_ui_anchor::VerticalAnchor::Bottom,
                        },
                    ))
                    .with_children(|p| {
                        p.spawn(TextBundle {
                            text: Text::from_section(
                                format!("{target}"),
                                TextStyle {
                                    font_size: 10.,
                                    color: BLACK.into(),
                                    ..Default::default()
                                },
                            ),
                            ..default()
                        });
                    });
            }
        }

        offset -= 0.05 * rad * (num as f32 - 1.0);
    }
}