//! Loads and renders a glTF file as a scene.

use bevy::{pbr::DirectionalLightShadowMap, prelude::*};
use bevy_inspector_egui::quick::WorldInspectorPlugin;
use bevy_npr::toon::{ToonBundle, ToonMaterial, ToonShaderPlugin};
use std::f32::consts::{FRAC_PI_4, PI};

fn main() {
    App::new()
        .insert_resource(DirectionalLightShadowMap { size: 4096 })
        .add_plugins((DefaultPlugins, ToonShaderPlugin))
        .add_plugins(WorldInspectorPlugin::new())
        .add_systems(PreStartup, setup)
        .add_systems(PreUpdate, update_materials)
        .add_systems(Update, animate_light_direction)
        .run();
}

#[derive(Component)]
struct GLTFScene;

fn setup(
    mut commands: Commands,
    mut _standard_materials: ResMut<Assets<StandardMaterial>>,
    mut toon_materials: ResMut<Assets<ToonMaterial>>,
    mut meshes: ResMut<Assets<Mesh>>,
    asset_server: Res<AssetServer>,
) {
    info!("init");
    commands.spawn(Camera3dBundle {
        transform: Transform::from_xyz(3.0, 4.0, 2.0).looking_at(Vec3::new(0.0, 0.0, 0.0), Vec3::Y),
        ..default()
    });

    commands.spawn(DirectionalLightBundle {
        directional_light: DirectionalLight {
            shadows_enabled: true,
            ..default()
        },
        ..default()
    });

    commands
        .spawn(SceneBundle {
            scene: asset_server.load("models/tuzi.glb#Scene0".to_string()),
            ..Default::default()
        })
        .insert(GLTFScene);

    commands.spawn(ToonBundle {
        mesh: meshes.add(shape::Plane::from_size(50.0).into()),
        material: toon_materials.add(Color::SILVER.into()),
        ..default()
    });
}

fn update_materials(
    mut commands: Commands,
    mut materials: ResMut<Assets<ToonMaterial>>,
    spheres: Query<(Entity, &Handle<StandardMaterial>, &Name)>,
) {
    for sphere in spheres.iter() {
        let (entity, material, name) = sphere;
        info!(
            "update_materials, entity: {:?}, material: {:?}, name: {:?}",
            entity, material, name
        );
        commands
            .entity(sphere.0)
            .remove::<Handle<StandardMaterial>>();
        commands
            .entity(sphere.0)
            .insert(materials.add(Color::SILVER.into()));
    }
}

fn animate_light_direction(
    time: Res<Time>,
    mut query: Query<&mut Transform, With<DirectionalLight>>,
) {
    for mut transform in &mut query {
        transform.rotation = Quat::from_euler(
            EulerRot::ZYX,
            0.0,
            time.elapsed_seconds() * PI / 5.0,
            -FRAC_PI_4,
        );
    }
}