1 files changed, 70 insertions, 0 deletions
diff --git a/client/lib/Game.ts b/client/lib/Game.ts
new file mode 100644
index 0000000..d6ffb47
--- /dev/null
+++ b/client/lib/Game.ts
@@ -0,0 +1,70 @@
+import { Entity } from "./entities";
+import { System } from "./systems";
+
+export class Game {
+  private entities: Map<number, Entity>;
+  private systems: Map<string, System>;
+  private systemOrder: string[];
+
+  private running: boolean;
+  private lastTimeStamp: number;
+
+  constructor() {
+    this.running = false;
+    this.systemOrder = [];
+    this.systems = new Map();
+    this.entities = new Map();
+  }
+
+  public start() {
+    this.lastTimeStamp = performance.now();
+    this.running = true;
+  }
+
+  public addEntity(entity: Entity) {
+    this.entities.set(entity.id, entity);
+  }
+
+  public getEntity(id: number): Entity {
+    return this.entities.get(id);
+  }
+
+  public removeEntity(id: number) {
+    this.entities.delete(id);
+  }
+
+  public addSystem(system: System) {
+    if (!this.systemOrder.includes(system.name)) {
+      this.systemOrder.push(system.name);
+    }
+    this.systems.set(system.name, system);
+  }
+
+  public getSystem(name: string): System {
+    return this.systems.get(name);
+  }
+
+  public doGameLoop = (timeStamp: number) => {
+    if (!this.running) {
+      return;
+    }
+
+    const dt = timeStamp - this.lastTimeStamp;
+    this.lastTimeStamp = timeStamp;
+
+    const componentEntities = new Map<string, Set<number>>();
+    this.entities.forEach((entity) =>
+      entity.getComponents().forEach((component) => {
+        if (!componentEntities.has(component.name)) {
+          componentEntities.set(component.name, new Set<number>([entity.id]));
+          return;
+        }
+        componentEntities.get(component.name).add(entity.id);
+      })
+    );
+
+    this.systemOrder.forEach((systemName) => {
+      this.systems.get(systemName).update(dt, this.entities, componentEntities);
+    });
+  };
+}