extern crate bevy;
extern crate bevy_liquidfun;

use bevy::prelude::*;
use bevy_liquidfun::{
    collision::b2Shape,
    dynamics::{b2BodyCommands, b2BodyDef, b2BodyType::Dynamic, b2Fixture, b2World},
    plugins::{LiquidFunDebugDrawPlugin, LiquidFunPlugin},
    utils::DebugDrawFixtures,
};

fn main() {
    App::new()
        .add_plugins((
            DefaultPlugins,
            LiquidFunPlugin::default(),
            LiquidFunDebugDrawPlugin,
        ))
        .add_systems(Startup, setup_camera)
        .add_systems(
            Startup,
            (
                setup_physics_world,
                setup_physics_bodies.after(setup_physics_world),
            ),
        )
        .run();
}

fn setup_camera(mut commands: Commands) {
    commands.spawn(Camera2dBundle {
        projection: OrthographicProjection {
            scale: 0.05,
            far: 1000.,
            near: -1000.,
            ..OrthographicProjection::default()
        },
        transform: Transform::from_translation(Vec3::new(0., 10., 0.)),
        ..Camera2dBundle::default()
    });
}

fn setup_physics_world(world: &mut World) {
    let gravity = Vec2::new(0., -9.81);
    let b2_world = b2World::new(gravity);
    world.insert_resource(b2_world);
}

fn setup_physics_bodies(mut commands: Commands) {
    {
        let fixture = b2Fixture::new(
            b2Shape::EdgeTwoSided {
                v1: Vec2::new(-40., 0.),
                v2: Vec2::new(40., 0.),
            },
            0.,
        );
        commands
            .spawn_body(&b2BodyDef::default(), fixture)
            .insert(DebugDrawFixtures::default_static());
    }

    let circle_shape = b2Shape::Circle {
        radius: 1.,
        position: Vec2::ZERO,
    };
    for i in 0..10 {
        let body_def = b2BodyDef {
            body_type: Dynamic,
            position: Vec2::new(0., 4. + 3. * i as f32),
            ..default()
        };
        commands
            .spawn_body(&body_def, b2Fixture::new(circle_shape.clone(), 1.))
            .insert(DebugDrawFixtures::default_dynamic());
    }
}