mod lunar;
mod setup;
mod controllable;

use avian2d::prelude::*;
use bevy::{prelude::*, winit::WinitSettings};
use controllable::Player;
fn main() {
    println!("Hello, world!");
    App::new()
        .add_plugins(DefaultPlugins)
        .insert_resource(ClearColor(Color::srgb(0.5, 0.5, 0.9)))
        .insert_resource(WinitSettings::game())
        .add_plugins(PhysicsPlugins::default())
        .add_systems(
            Startup,
            (
                setup::setup_starting_planet, 
                setup::setup_init, 
                lunar::setup_moon
            )
        )
        .add_systems(
            Update, 
            (
                update_gravitational_forces, 
                lunar::update_lunar_transform
            )
        )
        .run();
}

/*enum GameLevel {
    NearGround,
    Space,
    Moon,
    LunarSurface,
}*/
#[derive(Component)]
struct StartPlanet {
    display_name: String,
    planet_mass_kg: f32,
    radius: f32,
}

fn calculate_force_vector(
    mass_actor: f32,
    mass_incident: f32,
    pos_actor: Vec2,
    pos_incident: Vec2,
) -> Vec2 {
    let grav_const = 100.0;
    (grav_const * mass_actor * mass_incident / (pos_actor.distance_squared(pos_incident)))
        * Vec2 {
            x: pos_actor.x - pos_incident.x,
            y: pos_actor.y - pos_incident.y,
        }
        .normalize()
    /*Vec2 {
        x: pos_actor.x - pos_incident.x,
        y: pos_actor.y - pos_incident.y,
    }.normalize() *  50000.0*/
}
fn update_gravitational_forces(
    mut query_planet: Query<(Entity, &StartPlanet, &Transform)>,
    mut query_object: Query<(Entity, &Player, &mut ExternalForce, &Transform)>,
) {
    let (_es, ps, ts) = query_planet.single_mut();
    let (_ed, player, mut exd, td) = query_object.single_mut();
    let f = calculate_force_vector(
        ps.planet_mass_kg,
        player.mass_kg,
        ts.translation.xy(),
        td.translation.xy(),
    );
    info!("Force: {}, Transform: {}", f, td.translation);
    exd.apply_force(f);
}