begin refactoring movement logic out of player code into entity code.

js/entity.mjs

@@ -1,12 +1,14 @@
 import * as world from "./world.mjs";
+const BOX_SIZE = world.BOX_SIZE;
 
 
 
 const entities = [];
 
-export function create (x, y, color = "#fff") {
+export function create (box, x = 0, y = 0, color = "#fff") {
 	const entity = {
 		id: entities.length,
+		box,
 		x,
 		y,
 		color,
@@ -25,3 +27,45 @@ export function for_each (callback) {
 		callback(entity, entity.id);
 	});
 }
+
+function clamp_pos (entity) {
+	if (entity.x < 0) entity.x = 0;
+	if (entity.x >= BOX_SIZE) entity.x = BOX_SIZE - 1;
+	if (entity.y < 0) entity.y = 0;
+	if (entity.y >= BOX_SIZE) entity.y = BOX_SIZE - 1;
+	return entity;
+}
+
+export function set_pos (entity, x, y) {
+	entity.x = x;
+	entity.y = y;
+
+	/*
+	if (out_of_bounds(entity)) {
+		const could_exit = world.exit_box();
+		if (could_exit) {
+			set_player_pos(0, 0);
+		} else {
+			set_player_pos(previous_x, previous_y);
+		}
+		return;
+	}
+
+	if (world.get_tile(x, y)?.type === "box") {
+		world.enter_box(world.get_tile(x, y).box);
+		set_player_pos(world.CENTER, world.CENTER);
+		return;
+	}
+	*/
+	clamp_pos(entity);
+}
+
+export function move (entity, d_x, d_y) {
+	set_pos(entity, entity.x + d_x, entity.y + d_y);
+}
+
+function out_of_bounds (entity) {
+	const { x, y } = entity;
+	return x < 0 || x >= BOX_SIZE ||
+		y < 0 || y >= BOX_SIZE
+}

js/player.mjs

@@ -4,53 +4,25 @@ import * as entity from "./entity.mjs";
 
 
 
-const player = entity.create(2, 1, "#0f0");
-world.set_tile(player.x, player.y, { type: "player" });
+const player = entity.create(world.get_root(), 2, 1, "#0f0");
 
-function out_of_bounds (x, y) {
-	return x < 0 || x >= world.BOX_SIZE ||
-		y < 0 || y >= world.BOX_SIZE
-}
 
-export function set_player_pos (x, y) {
-	const previous_x = player.x;
-	const previous_y = player.y;
 
-	if (out_of_bounds(x, y)) {
-		const could_exit = world.exit_box();
-		if (could_exit) {
-			set_player_pos(0, 0);
-		} else {
-			set_player_pos(previous_x, previous_y);
-		}
-		return;
-	}
-
-	if (world.get_tile(x, y)?.type === "box") {
-		world.enter_box(world.get_tile(x, y).box);
-		set_player_pos(world.CENTER, world.CENTER);
-		return;
-	}
-
-	player.x = x;
-	player.y = y;
-}
-
-export function move_player (d_x, d_y) {
-	set_player_pos(player.x + d_x, player.y + d_y);
+export function move (d_x, d_y) {
+	entity.move(player, d_x, d_y);
 }
 
 on_press("ArrowLeft", _ => {
-	move_player(-1, 0);
+	move(-1, 0);
 });
 on_press("ArrowRight", _ => {
-	move_player(1, 0);
+	move(1, 0);
 });
 on_press("ArrowUp", _ => {
-	move_player(0, -1);
+	move(0, -1);
 });
 on_press("ArrowDown", _ => {
-	move_player(0, 1);
+	move(0, 1);
 });
 
 on_press(" ", _ => {

js/world.mjs

@@ -34,3 +34,7 @@ export function exit_box () {
 	}
 	return false;
 }
+
+export function get_root () {
+	return world;
+}