feat: avoid invoice writes GL entry with zero amount

packages/server/src/database/seeds/core/20230912121909_seed_tax_rates.ts

@@ -0,0 +1,14 @@
+import { TenantSeeder } from '@/lib/Seeder/TenantSeeder';
+import { InitialTaxRates } from '../data/TaxRates';
+
+export default class SeedTaxRates extends TenantSeeder {
+  /**
+   * Seeds initial tax rates to the organization.
+   */
+  up(knex) {
+    return knex('tax_rates').then(async () => {
+      // Inserts seed entries.
+      return knex('tax_rates').insert(InitialTaxRates);
+    });
+  }
+}

packages/server/src/database/seeds/data/TaxRates.ts

@@ -0,0 +1,30 @@
+export const InitialTaxRates = [
+  {
+    name: 'Tax Exempt',
+    code: 'TAX-EXEMPT',
+    description: 'Exempts goods or services from taxes.',
+    rate: 0,
+    active: 1,
+  },
+  {
+    name: 'Tax on Purchases',
+    code: 'TAX-PURCHASES',
+    description: 'Fee added to the cost when you buy items.',
+    rate: 0,
+    active: 1,
+  },
+  {
+    name: 'Tax on Sales',
+    code: 'TAX-SALES',
+    description: 'Fee added to the cost when you sell items.',
+    rate: 0,
+    active: 1,
+  },
+  {
+    name: 'Sales Tax on Imports',
+    code: 'TAX-IMPORTS',
+    description: 'Fee added to the cost when you sale to another country.',
+    rate: 0,
+    active: 1,
+  },
+];

packages/server/src/services/Items/ItemsEntriesService.ts

@@ -264,4 +264,13 @@ export default class ItemsEntriesService {
   public getTotalItemsEntries(entries: ItemEntry[]): number {
     return sumBy(entries, (e) => ItemEntry.calcAmount(e));
   }
+
+  /**
+   * Retrieve the non-zero tax items entries.
+   * @param {IItemEntry[]} entries -
+   * @returns {IItemEntry[]}
+   */
+  public getNonZeroEntries(entries: IItemEntry[]): IItemEntry[] {
+    return entries.filter((e) => e.taxRate > 0);
+  }
 }

packages/server/src/services/Sales/Invoices/InvoiceGLEntries.ts

@@ -6,12 +6,12 @@ import {
   ILedgerEntry,
   AccountNormal,
   ILedger,
-  ITaxTransaction,
 } from '@/interfaces';
 import { Service, Inject } from 'typedi';
 import Ledger from '@/services/Accounting/Ledger';
 import LedgerStorageService from '@/services/Accounting/LedgerStorageService';
 import HasTenancyService from '@/services/Tenancy/TenancyService';
+import ItemsEntriesService from '@/services/Items/ItemsEntriesService';
 
 @Service()
 export class SaleInvoiceGLEntries {
@@ -21,6 +21,9 @@ export class SaleInvoiceGLEntries {
   @Inject()
   private ledegrRepository: LedgerStorageService;
 
+  @Inject()
+  private itemsEntriesService: ItemsEntriesService;
+
   /**
    * Writes a sale invoice GL entries.
    * @param {number} tenantId - Tenant id.
@@ -93,7 +96,7 @@ export class SaleInvoiceGLEntries {
       'SaleInvoice',
       trx
     );
-};
+  };
 
   /**
    * Retrieves the given invoice ledger.
@@ -218,11 +221,33 @@ export class SaleInvoiceGLEntries {
         index: index + 3,
         accountNormal: AccountNormal.CREDIT,
         taxRateId: entry.taxRateId,
-        taxRate : entry.taxRate,
+        taxRate: entry.taxRate,
       };
     }
   );
 
+  /**
+   * Retrieves the invoice tax GL entries.
+   * @param {ISaleInvoice} saleInvoice
+   * @param {number} taxPayableAccountId
+   * @returns {ILedgerEntry[]}
+   */
+  private getInvoiceTaxEntries = (
+    saleInvoice: ISaleInvoice,
+    taxPayableAccountId: number
+  ): ILedgerEntry[] => {
+    // Retrieves the non-zero tax entries.
+    const nonZeroTaxEntries = this.itemsEntriesService.getNonZeroEntries(
+      saleInvoice.entries
+    );
+    const transformTaxEntry = this.getInvoiceTaxEntry(
+      saleInvoice,
+      taxPayableAccountId
+    );
+    // Transforms the non-zero tax entries to GL entries.
+    return nonZeroTaxEntries.map(transformTaxEntry);
+  };
+
   /**
    * Retrieves the invoice GL entries.
    * @param {ISaleInvoice} saleInvoice
@@ -239,13 +264,12 @@ export class SaleInvoiceGLEntries {
       ARAccountId
     );
     const transformItemEntry = this.getInvoiceItemEntry(saleInvoice);
-    const transformTaxEntry = this.getInvoiceTaxEntry(
+    const creditEntries = saleInvoice.entries.map(transformItemEntry);
+
+    const taxEntries = this.getInvoiceTaxEntries(
       saleInvoice,
       taxPayableAccountId
     );
-    const creditEntries = saleInvoice.entries.map(transformItemEntry);
-    const taxEntries = saleInvoice.entries.map(transformTaxEntry);
-
     return [receivableEntry, ...creditEntries, ...taxEntries];
   };
 }