/*
 * Blue Engine by Elham Aryanpur
 *
 * The license is same as the one on the root.
*/

use blue_engine::{
    header::{Engine, WindowDescriptor},
    primitive_shapes::{cube, uv_sphere},
};
use blue_engine_utilities::{physics::Physics, raycast::Raycast, FlyCamera};
use rapier3d::prelude::*;

fn main() -> eyre::Result<()> {
    let mut engine = Engine::new_config(WindowDescriptor {
        width: 1500,
        height: 1000,
        title: "Fly Camera",
        ..Default::default()
    })?;

    let mut physics = Physics::new();
    let fly_camera = FlyCamera::new(&mut engine.camera);

    cube("floor", &mut engine.renderer, &mut engine.objects)?;
    engine
        .objects
        .get_mut("floor")
        .unwrap()
        .set_scale(2f32, 0.3f32, 2f32);
    engine
        .objects
        .get_mut("floor")
        .unwrap()
        .set_position(0f32, -1f32, 0f32);
    let collider = ColliderBuilder::cuboid(2.0, 0.3f32, 2.0)
        .translation([0f32, -1f32, 0f32].into())
        .build();
    physics.insert_collider("floor", collider);

    uv_sphere(
        "ball",
        (18, 46, 1f32),
        &mut engine.renderer,
        &mut engine.objects,
    )?;
    engine
        .objects
        .get_mut("ball")
        .unwrap()
        .set_color(0.3, 0.3, 0.6, 1f32);
    engine
        .objects
        .get_mut("ball")
        .unwrap()
        .set_position(0f32, 10f32, 0f32);
    let rigid_body = RigidBodyBuilder::dynamic()
        .translation(vector![0.0, 10.0, 0.0])
        .build();
    let collider = ColliderBuilder::ball(1f32).restitution(0.7).build();
    let ball_body_handle = physics.insert_rigid_body("ball", rigid_body);
    physics.insert_collider_with_parent("ball collider", collider, ball_body_handle);

    uv_sphere(
        "ball2",
        (18, 46, 1f32),
        &mut engine.renderer,
        &mut engine.objects,
    )?;
    engine
        .objects
        .get_mut("ball2")
        .unwrap()
        .set_color(0.3, 0.3, 0.6, 1f32);
    engine
        .objects
        .get_mut("ball2")
        .unwrap()
        .set_position(0.05f32, 13f32, 0.0f32);
    let rigid_body = RigidBodyBuilder::dynamic()
        .translation(vector![0.05, 13.0, 0.0])
        .build();
    let collider = ColliderBuilder::ball(1f32).restitution(0.7).build();
    let ball_body_handle = physics.insert_rigid_body("ball2", rigid_body);
    physics.insert_collider_with_parent("ball2 collider", collider, ball_body_handle);

    let mut raycast = Raycast::new(engine.camera.get("main").unwrap());

    engine.signals.add_signal("fly", Box::new(fly_camera));
    engine.signals.add_signal("physics", Box::new(physics));

    engine.update_loop(move |_, window, _, input, camera, signals| {
        let physics = signals.get_signal::<Physics>("physics").unwrap().unwrap();
        raycast.update(
            camera.get("main").unwrap(),
            input,
            &window.as_ref().unwrap().inner_size(),
        );

        let ray = Ray::new(
            camera.get("main").unwrap().position.into(),
            raycast.get_current_ray(),
        );
        let max_toi = 4.0;
        let solid = true;
        let filter = QueryFilter::default();

        if let Some((handle, toi)) = physics.query_pipeline.cast_ray(
            &physics.rigid_body_set,
            &physics.collider_set,
            &ray,
            max_toi,
            solid,
            filter,
        ) {
            // The first collider hit has the handle `handle` and it hit after
            // the ray travelled a distance equal to `ray.dir * toi`.
            let hit_point = ray.point_at(toi); // Same as: `ray.origin + ray.dir * toi`
            println!("Collider {:?} hit at point {}", handle, hit_point);
        }
    })?;

    Ok(())
}