feat: discount sale and purchase transactions

packages/server/src/models/CreditNote.ts

@@ -5,12 +5,20 @@ import CustomViewBaseModel from './CustomViewBaseModel';
 import { DEFAULT_VIEWS } from '@/services/CreditNotes/constants';
 import ModelSearchable from './ModelSearchable';
 import CreditNoteMeta from './CreditNote.Meta';
+import { DiscountType } from '@/interfaces';
 
 export default class CreditNote extends mixin(TenantModel, [
   ModelSetting,
   CustomViewBaseModel,
   ModelSearchable,
 ]) {
+  public amount: number;
+  public exchangeRate: number;
+  public openedAt: Date;
+  public discount: number;
+  public discountType: DiscountType;
+  public adjustment: number;
+
   /**
    * Table name
    */
@@ -48,6 +56,42 @@ export default class CreditNote extends mixin(TenantModel, [
     return this.amount * this.exchangeRate;
   }
 
+  /**
+   * Credit note subtotal.
+   * @returns {number}
+   */
+  get subtotal() {
+    return this.amount;
+  }
+
+  /**
+   * Credit note subtotal in local currency.
+   * @returns {number}
+   */
+  get subtotalLocal() {
+    return this.subtotal * this.exchangeRate;
+  }
+
+  /**
+   * Credit note total.
+   * @returns {number}
+   */
+  get total() {
+    const discountAmount = this.discountType === DiscountType.Amount
+      ? this.discount
+      : this.subtotal * (this.discount / 100);
+
+    return this.subtotal - discountAmount - this.adjustment;
+  }
+
+  /**
+   * Credit note total in local currency.
+   * @returns {number}
+   */
+  get totalLocal() {
+    return this.total * this.exchangeRate;
+  }
+
   /**
    * Detarmines whether the credit note is draft.
    * @returns {boolean}