Add effects/attributes to all game entities

src/Area.js

@@ -23,7 +23,7 @@ const AreaFloor = require('./AreaFloor');
  */
 class Area extends GameEntity {
   constructor(bundle, name, manifest) {
-    super();
+    super(manifest);
     this.bundle = bundle;
     this.name = name;
     this.title = manifest.title;

src/AreaOfEffectDamage.js

@@ -0,0 +1,54 @@
+'use strict';
+
+const Damage = require('./Damage');
+const Room = require('./Room');
+const Character = require('./Character');
+
+/**
+ * Damage class used for applying damage to multiple entities in a room. By
+ * default it will target all npcs in the room. To customize this behavior you
+ * can extend this class and override the `getValidTargets` method
+ */
+class AreaOfEffectDamage extends Damage
+{
+  /**
+   * @param {Room|Character} target
+   * @throws RangeError
+   * @fires Room#areaDamage
+   */
+  commit(room) {
+    if (!(room instanceof Room)) {
+      if (!(room instanceof Character)) {
+        throw new RangeError('AreaOfEffectDamage commit target must be an instance of Room or Character');
+      }
+
+      super.commit(room);
+      return;
+    }
+
+    const targets = this.getValidTargets(room);
+    for (const target of targets) {
+      super.commit(target);
+    }
+
+    /**
+     * @event Room#areaDamage
+     * @param {Damage} damage
+     * @param {Array<Character>} targets
+     */
+    room.emit('areaDamage', this, targets);
+  }
+
+  /**
+   * Override this method to customize valid targets such as
+   * only targeting hostile npcs, or only targeting players, etc.
+   * @param {Room} room
+   * @return {Array<Character>}
+   */
+  getValidTargets(room) {
+    const targets = [...room.npcs];
+    return targets.filter(t => t.hasAttribute(this.attribute));
+  }
+}
+
+module.exports = AreaOfEffectDamage;

src/AreaOfEffectHeal.js

@@ -0,0 +1,55 @@
+'use strict';
+
+const Heal = require('./Heal');
+const Room = require('./Room');
+const Character = require('./Character');
+
+/**
+ * Heal class used for applying healing to multiple entities in a room. By
+ * default it will target all players in the room. To customize this behavior you
+ * can extend this class and override the `getValidTargets` method
+ */
+class AreaOfEffectHeal extends Heal
+{
+  /**
+   * @param {Room|Character} target
+   * @throws RangeError
+   * @fires Room#areaHeal
+   */
+  commit(room) {
+    if (!(room instanceof Room)) {
+      if (!(room instanceof Character)) {
+        throw new RangeError('AreaOfEffectHeal commit target must be an instance of Room or Character');
+      }
+
+      super.commit(room);
+      return;
+    }
+
+    const targets = this.getValidTargets(room);
+    for (const target of targets) {
+      super.commit(target);
+    }
+
+
+    /**
+     * @event Room#areaHeal
+     * @param {Heal} heal
+     * @param {Array<Character>} targets
+     */
+    room.emit('areaHeal', this, targets);
+  }
+
+  /**
+   * Override this method to customize valid targets such as
+   * only targeting hostile npcs, or only targeting players, etc.
+   * @param {Room} room
+   * @return {Array<Character>}
+   */
+  getValidTargets(room) {
+    const targets = [...room.players];
+    return targets.filter(t => t.hasAttribute(this.attribute));
+  }
+}
+
+module.exports = AreaOfEffectHeal;