use raidillon_app::prelude::*;

mod systems;
use glam::{Quat, Vec3};
use rapier3d::dynamics::{CoefficientCombineRule, RigidBodyType};
use rapier3d::prelude::ColliderBuilder;
use winit::event::{Event, WindowEvent};
use systems::debug_camera::FPSDebugCameraSystem;
use crate::systems::common::should_draw_menu;
use crate::systems::{
    DisplaySettings, KeybindsSystem, KinematicCharacterController, MenuSystem, PhysicsSystem,
    PhysicsDebugSystem,
};

const TEST_GLTF: &str = "checkered-sphere.glb";
const PLANE_GLTF: &str = "plane.glb";
const MAIN_SCENE_ID: &str = "main_scene";

#[derive(Default)]
struct UpdateAspectRatioSystem;
impl System for UpdateAspectRatioSystem {
    fn handle_event(&mut self, res: &mut EngineResources, scene: &mut Scene) {
        let pctx = res.get::<PlatformContext>().unwrap();

        if let Event::WindowEvent { event: WindowEvent::Resized(sz), .. } =
            pctx.current_event
        {
            scene.world
                .query_mut::<&mut Camera>()
                .into_iter()
                .for_each(|(_, cam)| {
                    cam.aspect = sz.width as f32 / sz.height as f32;
                });
        }
    }
}

#[derive(Default)]
struct MainSystem;

impl System for MainSystem {
    fn load_world(&mut self, res: &mut EngineResources, scene: &mut Scene) {
        let pctx = res.get::<PlatformContext>().expect("PlatformContext missing").clone();
        let physics = scene.resources.get_mut::<Physics>().expect("Physics missing");

        // Spawn Sphere
        {
            let tr = Transform {
                translation: Vec3::new(0.0, 5.0, 0.0),
                rotation: Quat::IDENTITY,
                scale: Vec3::new(1.0, 1.0, 1.0),
            };
            let collider = ColliderBuilder::ball(1.0)
                .restitution(0.7)
                .restitution_combine_rule(CoefficientCombineRule::Max)
                .build();
            let rb_handle = physics.add_rigid_body(RigidBodyType::Dynamic, tr, collider);
            pctx.asset_manager.borrow_mut().load_gltf(TEST_GLTF, &model_path(TEST_GLTF));
            scene.world.spawn((
                tr,
                ModelHandle(TEST_GLTF),
                RigidBodyComponent(rb_handle),
            ));
        }
        // Spawn Plane
        {
            let tr = Transform {
                translation: Vec3::new(0.0, 0.0, 0.0),
                rotation: Quat::IDENTITY,
                scale: Vec3::new(10.0, 1.0, 10.0),
            };
            let collider = ColliderBuilder::cuboid(10.0, 0.01, 10.0).build();
            let rb_handle = physics.add_rigid_body(RigidBodyType::Fixed, tr, collider);
            pctx.asset_manager.borrow_mut().load_gltf(PLANE_GLTF, &model_path(PLANE_GLTF));
            scene.world.spawn((
                tr,
                ModelHandle(PLANE_GLTF),
                RigidBodyComponent(rb_handle),
            ));
        }

        scene.world.spawn((Camera {
            eye:    Vec3::new(0.0, 2.0, 3.0),
            center: Vec3::ZERO,
            up:     Vec3::Y,
            fovy:   60_f32.to_radians(),
            aspect: pctx.frame_width / pctx.frame_height,
            znear:  0.1,
            zfar:   100.0},
            CameraMode::default(),
        ));
    }

    fn frame_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {
        let (
            pctx,
            input,
        ) = res.get_many_mut::<(
            PlatformContext,
            InputState,
        )>().unwrap();

        let mut egui_queue = pctx.egui_queue.borrow_mut();
        let time_ctx = pctx.time_ctx.clone();
        let mut character_pos = Vec3::ZERO;
        for (_ent, (tr, ch_component)) in scene.world.query::<(&Transform, &CharacterBodyComponent)>().iter() {
            character_pos = tr.translation;
        }
        egui_queue.queue(move |egui_ctx| {
            // disable text selection on all labels.
            egui_ctx.style_mut(|style| {
                style.interaction.selectable_labels = false;
            });

            egui::Window::new("Debug").show(egui_ctx, |ui| {
                ui.label("Hello World!");
                ui.label(format!("Frame Delta: {:.3}", time_ctx.frame_dt));
                ui.label(format!("Fixed Delta: {:.3}", time_ctx.fixed_dt));
                ui.label(format!("FPS: {:.3}", 1.0 / time_ctx.frame_dt));
                ui.label(format!("Character POS: {character_pos:.3}"));
            });
        });
    }
}

fn main() {
    raidillon_app::App::new()
        .add_system::<PhysicsSystem>()
        .add_system::<PhysicsDebugSystem>()
        .add_system::<KeybindsSystem>()
        .add_system::<KinematicCharacterController>()
        .add_system::<FPSDebugCameraSystem>()
        .add_system::<MenuSystem>()
        .add_system::<DisplaySettings>()
        .add_system::<MainSystem>()
        .add_system::<UpdateAspectRatioSystem>()
        .add_scene(MAIN_SCENE_ID, Scene::new(MAIN_SCENE_ID.to_owned(), None))
        .set_active_scene(MAIN_SCENE_ID)
        .run("Raidillon".to_string(), 2560, 1080);
}