1 files changed, 138 insertions, 0 deletions
diff --git a/static/src/engine/network.ts b/static/src/engine/network.ts
new file mode 100644
index 0000000..850da65
--- /dev/null
+++ b/static/src/engine/network.ts
@@ -0,0 +1,138 @@
+import {
+  ComponentType,
+  PositionComponent,
+  TrailingPositionComponent,
+} from "./component";
+import { create_cat, create_laser, Entity, EntityType } from "./entity";
+import {
+  EntityBornEvent,
+  EntityDeathEvent,
+  EntityPositionUpdateEvent,
+  EventPublisher,
+  EventQueue,
+  EventType,
+  InitialStateEvent,
+  SetControllableEvent,
+} from "./events";
+import { Game } from "./game";
+import { InputSystem } from "./input";
+import { RenderSystem } from "./render";
+import { System, SystemType } from "./system";
+
+export class NetworkSystem extends System {
+  constructor(
+    private readonly event_queue: EventQueue,
+    private readonly event_publisher: EventPublisher,
+  ) {
+    super(SystemType.NETWORK);
+  }
+
+  public update(_dt: number, game: Game) {
+    const events = this.event_queue.peek();
+    for (const event of events) {
+      switch (event.event_type) {
+        case EventType.INITIAL_STATE:
+          this.process_initial_state_event(event as InitialStateEvent, game);
+          break;
+        case EventType.SET_CONTROLLABLE:
+          this.process_set_controllable_event(
+            event as SetControllableEvent,
+            game,
+          );
+          break;
+        case EventType.ENTITY_BORN:
+          this.process_entity_born_event(event as EntityBornEvent, game);
+          break;
+        case EventType.ENTITY_POSITION_UPDATE:
+          this.process_entity_position_update_event(
+            event as EntityPositionUpdateEvent,
+            game,
+          );
+          break;
+        case EventType.ENTITY_DEATH:
+          this.process_entity_death_event(event as EntityDeathEvent, game);
+          break;
+      }
+    }
+
+    this.event_queue.clear();
+    this.event_publisher.publish();
+  }
+
+  private process_initial_state_event(event: InitialStateEvent, game: Game) {
+    console.log("received initial state", event);
+    const { world, entities } = event.data;
+    const render_system = game.get_system<RenderSystem>(SystemType.RENDER);
+    if (!render_system) {
+      console.error("render system not found");
+      return;
+    }
+    render_system.set_world_dimensions(world.width, world.height);
+    Object.values(entities).forEach((entity) =>
+      game.put_entity(this.process_new_entity(entity)),
+    );
+  }
+
+  private process_entity_position_update_event(
+    event: EntityPositionUpdateEvent,
+    game: Game,
+  ) {
+    console.log("received entity position update", event);
+    const { position, id } = event.data;
+    const entity = game.get_entity(id);
+    if (typeof entity === "undefined") return;
+
+    const position_component = entity.components[
+      ComponentType.POSITION
+    ] as PositionComponent;
+    position_component.x = position.x;
+    position_component.y = position.y;
+
+    if (ComponentType.TRAILING_POSITION in entity.components) {
+      const trailing_position = entity.components[
+        ComponentType.TRAILING_POSITION
+      ] as TrailingPositionComponent;
+      trailing_position.trails.push({
+        x: position_component.x,
+        y: position_component.y,
+        time: Date.now(),
+      });
+    }
+  }
+
+  private process_entity_born_event(event: EntityBornEvent, game: Game) {
+    console.log("received a new entity", event);
+    const { entity } = event.data;
+    game.put_entity(this.process_new_entity(entity));
+  }
+
+  private process_new_entity(entity: Entity): Entity {
+    if (entity.entity_type === EntityType.LASER) {
+      return create_laser(entity);
+    }
+    if (entity.entity_type === EntityType.CAT) {
+      return create_cat(entity);
+    }
+    return entity;
+  }
+
+  private process_entity_death_event(event: EntityDeathEvent, game: Game) {
+    console.log("an entity died D:", event);
+    const { id } = event.data;
+    game.remove_entity(id);
+  }
+
+  private process_set_controllable_event(
+    event: SetControllableEvent,
+    game: Game,
+  ) {
+    console.log("got a controllable event", event);
+    if (event.data.client_id !== game.client_id) {
+      console.warn("got controllable event for client that is not us");
+      return;
+    }
+
+    const input_system = game.get_system<InputSystem>(SystemType.INPUT)!;
+    input_system.add_controllable_entity(event.data.id);
+  }
+}