Create EffectHelper class

src/database/entities/app/UserEffect.ts

@@ -1,5 +1,6 @@
 import {Column, Entity} from "typeorm";
 import AppBaseEntity from "../../../contracts/AppBaseEntity";
+import AppDataSource from "../../dataSources/appDataSource";
 
 @Entity()
 export default class UserEffect extends AppBaseEntity {
@@ -48,4 +49,12 @@ export default class UserEffect extends AppBaseEntity {
 
         return false;
     }
+
+    public static async FetchOneByUserIdAndName(userId: string, name: string): Promise<UserEffect | null> {
+        const repository = AppDataSource.getRepository(UserEffect);
+
+        const single = await repository.findOne({ where: { UserId: userId, Name: name } });
+
+        return single;
+    }
 }

src/helpers/EffectHelper.ts

@@ -0,0 +1,49 @@
+import UserEffect from "../database/entities/app/UserEffect";
+
+export default class EffectHelper {
+    public static async AddEffectToUserInventory(userId: string, name: string, quantity: number = 1) {
+        let effect = await UserEffect.FetchOneByUserIdAndName(userId, name);
+
+        if (!effect) {
+            effect = new UserEffect(name, userId, quantity);
+        } else {
+            effect.AddUnused(quantity);
+        }
+
+        await effect.Save(UserEffect, effect);
+    }
+
+    public static async UseEffect(userId: string, name: string, whenExpires: Date): Promise<boolean> {
+        const effect = await UserEffect.FetchOneByUserIdAndName(userId, name);
+        const now = new Date();
+
+        if (!effect || effect.Unused == 0) {
+            return false;
+        }
+
+        if (effect.WhenExpires && now < effect.WhenExpires) {
+            return false;
+        }
+
+        effect.UseEffect(whenExpires);
+
+        await effect.Save(UserEffect, effect);
+
+        return true;
+    }
+
+    public static async HasEffect(userId: string, name: string): Promise<boolean> {
+        const effect = await UserEffect.FetchOneByUserIdAndName(userId, name);
+        const now = new Date();
+
+        if (!effect || !effect.WhenExpires) {
+            return false;
+        }
+
+        if (now > effect.WhenExpires) {
+            return false;
+        }
+
+        return true;
+    }
+}