Feature/Refactor to use ecs architecture (#14)

Reviewed-on: #14
Co-authored-by: Juan Sebastian Montoya <juansmm@outlook.com>
Co-committed-by: Juan Sebastian Montoya <juansmm@outlook.com>

src/game/EntityFactory.js

@@ -0,0 +1,157 @@
+import { Transform } from '../components/Transform.js';
+import { Velocity } from '../components/Velocity.js';
+import { MeshComponent } from '../components/MeshComponent.js';
+import { Collidable } from '../components/Collidable.js';
+import { Health } from '../components/Health.js';
+import { PlayerTag, CoinTag, ObstacleTag, BoundaryConstrained } from '../components/Tags.js';
+
+/**
+ * EntityFactory - creates pre-configured game entities with appropriate components.
+ * Centralizes entity creation logic for consistency.
+ * 
+ * @typedef {import('../ecs/World.js').EntityId} EntityId
+ */
+export class EntityFactory {
+  /**
+   * @param {import('../ecs/World.js').World} world - The ECS world
+   * @param {THREE.Scene} scene - The Three.js scene
+   */
+  constructor(world, scene) {
+    /** @type {import('../ecs/World.js').World} */
+    this.world = world;
+    
+    /** @type {THREE.Scene} */
+    this.scene = scene;
+    
+    /** @type {number} Size of the game ground/play area */
+    this.groundSize = 30;
+  }
+
+  /**
+   * Create the player entity
+   * @returns {EntityId} The player entity ID
+   */
+  createPlayer() {
+    const entity = this.world.createEntity();
+
+    // Create mesh
+    const geometry = new window.THREE.BoxGeometry(1, 1, 1);
+    const material = new window.THREE.MeshStandardMaterial({
+      color: 0x4169E1,
+      metalness: 0.3,
+      roughness: 0.4
+    });
+    const mesh = new window.THREE.Mesh(geometry, material);
+    mesh.castShadow = true;
+    mesh.receiveShadow = true;
+    this.scene.add(mesh);
+
+    // Add components
+    this.world.addComponent(entity, new Transform(0, 0.5, 0));
+    this.world.addComponent(entity, new Velocity());
+    this.world.addComponent(entity, new MeshComponent(mesh));
+    this.world.addComponent(entity, new Collidable(0, 'player')); // Player center point (original behavior)
+    this.world.addComponent(entity, new Health(100));
+    this.world.addComponent(entity, new PlayerTag());
+    this.world.addComponent(entity, new BoundaryConstrained(this.groundSize));
+
+    return entity;
+  }
+
+  /**
+   * Create a collectible coin entity
+   * @param {number} [index=0] - Unique index for animation offset
+   * @returns {EntityId} The coin entity ID
+   */
+  createCoin(index = 0) {
+    const entity = this.world.createEntity();
+
+    // Create mesh
+    const geometry = new window.THREE.SphereGeometry(0.3, 16, 16);
+    const material = new window.THREE.MeshStandardMaterial({
+      color: 0xFFD700,
+      metalness: 0.8,
+      roughness: 0.2,
+      emissive: 0xFFD700,
+      emissiveIntensity: 0.3
+    });
+    const mesh = new window.THREE.Mesh(geometry, material);
+    mesh.castShadow = true;
+    mesh.receiveShadow = true;
+    this.scene.add(mesh);
+
+    // Random position
+    const x = (Math.random() - 0.5) * (this.groundSize - 4);
+    const z = (Math.random() - 0.5) * (this.groundSize - 4);
+
+    // Add components
+    this.world.addComponent(entity, new Transform(x, 0.5, z));
+    this.world.addComponent(entity, new MeshComponent(mesh));
+    this.world.addComponent(entity, new Collidable(0.8, 'coin'));
+    this.world.addComponent(entity, new CoinTag(index));
+
+    return entity;
+  }
+
+  /**
+   * Create an obstacle entity
+   * @returns {EntityId} The obstacle entity ID
+   */
+  createObstacle() {
+    const entity = this.world.createEntity();
+
+    // Create mesh
+    const geometry = new window.THREE.BoxGeometry(1.5, 2, 1.5);
+    const material = new window.THREE.MeshStandardMaterial({
+      color: 0xFF4500,
+      metalness: 0.3,
+      roughness: 0.7
+    });
+    const mesh = new window.THREE.Mesh(geometry, material);
+    mesh.castShadow = true;
+    mesh.receiveShadow = true;
+    this.scene.add(mesh);
+
+    // Random position (away from center)
+    let posX, posZ;
+    do {
+      posX = (Math.random() - 0.5) * (this.groundSize - 4);
+      posZ = (Math.random() - 0.5) * (this.groundSize - 4);
+    } while (Math.abs(posX) < 3 && Math.abs(posZ) < 3);
+
+    // Random velocity
+    const velocity = new Velocity(
+      (Math.random() - 0.5) * 0.05,
+      0,
+      (Math.random() - 0.5) * 0.05
+    );
+
+    // Add components
+    this.world.addComponent(entity, new Transform(posX, 1, posZ));
+    this.world.addComponent(entity, velocity);
+    this.world.addComponent(entity, new MeshComponent(mesh));
+    this.world.addComponent(entity, new Collidable(1.5, 'obstacle'));
+    this.world.addComponent(entity, new ObstacleTag());
+    this.world.addComponent(entity, new BoundaryConstrained(this.groundSize));
+
+    return entity;
+  }
+
+  /**
+   * Remove entity and its mesh from scene
+   * @param {EntityId} entityId - The entity to destroy
+   */
+  destroyEntity(entityId) {
+    // Remove mesh from scene if it exists
+    const meshComp = this.world.getComponent(entityId, MeshComponent);
+    if (meshComp) {
+      this.scene.remove(meshComp.mesh);
+      meshComp.mesh.geometry.dispose();
+      meshComp.mesh.material.dispose();
+    }
+
+    // Remove entity from world
+    this.world.removeEntity(entityId);
+  }
+}
+