let sim_running: bool = false;
let sim_transforms: mat4_box_t[];
let sim_object_script_map: map_t<object_t, string> = map_create();
let sim_record: bool                               = false;
let sim_initialized: bool                          = false;

function sim_init() {
	if (sim_initialized) {
		return;
	}
	physics_world_create();
	sim_initialized = true;
}

function sim_update() {

	render_path_raytrace_ready = false;

	if (sim_running) {
		// if (render_path_raytrace_frame != 1) {
		// return;
		// }

		let objects: object_t[] = map_keys(sim_object_script_map);
		for (let i: i32 = 0; i < objects.length; ++i) {
			let o: object_t  = objects[i];
			let s: string    = map_get(sim_object_script_map, o);
			let addr: string = i64_to_string((i64)(o.transform));
			s                = "{let transform=" + addr + ";" + s + "}";
			js_eval(s);
		}

		let world: physics_world_t = physics_world_active;
		physics_world_update(world);

		iron_delay_idle_sleep();

		if (sim_record) {
			let rt: render_target_t = map_get(render_path_render_targets, "last");
			let pixels: buffer_t    = gpu_get_texture_pixels(rt._image);
			/// if IRON_BGRA
			export_arm_bgra_swap(pixels);
			/// end
			iron_mp4_encode(pixels);
		}
	}
}

function sim_play() {
	sim_running = true;

	if (sim_record) {
		if (project_filepath == "") {
			console_error(tr("Save project first"));
			sim_record = false;
			return;
		}
		let path: string        = path_base_dir(project_filepath) + "/output.mp4";
		let rt: render_target_t = map_get(render_path_render_targets, "last");
		iron_mp4_begin(path, rt._image.width, rt._image.height);
	}

	// Save transforms
	sim_transforms           = [];
	let pos: mesh_object_t[] = project_paint_objects;
	for (let i: i32 = 0; i < pos.length; ++i) {
		let m: mat4_box_t = {v : pos[i].base.transform.local};
		array_push(sim_transforms, m);
	}
}

function sim_stop() {
	sim_running = false;

	if (sim_record) {
		iron_mp4_end();
	}

	// Restore transforms
	let pos: mesh_object_t[] = project_paint_objects;
	for (let i: i32 = 0; i < pos.length; ++i) {
		transform_set_matrix(pos[i].base.transform, sim_transforms[i].v);

		let pb: physics_body_t = map_get(physics_body_object_map, pos[i].base.uid);
		if (pb != null) {
			physics_body_sync_transform(pb);
		}
	}
}

function sim_add_body(o: object_t, shape: physics_shape_t, mass: f32) {
	let body: physics_body_t = physics_body_create();
	body.shape               = shape;
	body.mass                = mass;
	physics_body_init(body, o);
}

function sim_remove_body(uid: i32) {
	physics_body_remove(uid);
}

function sim_duplicate() {
	// Mesh
	let so: mesh_object_t  = context_raw.selected_object.ext;
	let dup: mesh_object_t = scene_add_mesh_object(so.data, so.material, so.base.parent);
	transform_set_matrix(dup.base.transform, so.base.transform.local);
	array_push(project_paint_objects, dup);
	dup.base.name = so.base.name;

	// Physics
	let pb: physics_body_t = map_get(physics_body_object_map, so.base.uid);
	if (pb != null) {
		let pbdup: physics_body_t = physics_body_create();
		pbdup.shape               = pb.shape;
		pbdup.mass                = pb.mass;
		physics_body_init(pbdup, dup.base);
	}

	_tab_scene_paint_object_length++;
	tab_scene_sort();
}

function sim_delete() {
	let so: mesh_object_t = context_raw.selected_object.ext;
	array_remove(project_paint_objects, so);
	mesh_object_remove(so);
	sim_remove_body(so.base.uid);

	_tab_scene_paint_object_length--;
	tab_scene_sort();
}