feat(server): wip tax rate on sale invoice service

packages/server/src/database/migrations/20230810191606_create_tax_rates.js

@@ -11,14 +11,25 @@ exports.up = (knex) => {
       table.timestamps();
     })
     .table('items_entries', (table) => {
-      table.boolean(['is_tax_exclusive']);
+      table.boolean('is_tax_exclusive');
       table.string('tax_code');
       table.decimal('tax_rate');
-      table.decimal('tax_amount_withheld')
     })
     .table('sales_invoices', (table) => {
-      table.boolean(['is_tax_exclusive']);
-      table.decimal('tax_amount_withheld')
+      table.boolean('is_tax_exclusive');
+      table.decimal('tax_amount_withheld');
+    })
+    .createTable('tax_rate_transactions', (table) => {
+      table.increments('id');
+
+      table.string('tax_name');
+      table.string('tax_code');
+
+      table.string('reference_type');
+      table.integer('reference_id');
+
+      table.decimal('tax_amount');
+      table.integer('tax_account_id').unsigned();
     });
 };
 

packages/server/src/database/seeds/data/accounts.js

@@ -1,3 +1,13 @@
+export const TaxPayableAccount = {
+  name: 'Tax Payable',
+  slug: 'tax-payable',
+  account_type: 'other-current-liability',
+  code: '20006',
+  description: '',
+  active: 1,
+  index: 1,
+  predefined: 1,
+};
 
 export default [
   {
@@ -81,7 +91,8 @@ export default [
     parent_account_id: null,
     index: 1,
     active: 1,
-    description:'An account that holds valuation of products or goods that availiable for sale.',
+    description:
+      'An account that holds valuation of products or goods that availiable for sale.',
   },
 
   // Libilities
@@ -122,7 +133,8 @@ export default [
     slug: 'opening-balance-liabilities',
     account_type: 'other-current-liability',
     code: '20004',
-    description:'This account will hold the difference in the debits and credits entered during the opening balance..',
+    description:
+      'This account will hold the difference in the debits and credits entered during the opening balance..',
     active: 1,
     index: 1,
     predefined: 0,
@@ -138,16 +150,7 @@ export default [
     index: 1,
     predefined: 0,
   },
-  {
-    name:'Sales Tax Payable',
-    slug: 'owner-drawings',
-    account_type: 'other-current-liability',
-    code: '20006',
-    description: '',
-    active: 1,
-    index: 1,
-    predefined: 1,
-  },
+  TaxPayableAccount,
 
   // Equity
   {
@@ -155,7 +158,8 @@ export default [
     slug: 'retained-earnings',
     account_type: 'equity',
     code: '30001',
-    description:'Retained earnings tracks net income from previous fiscal years.',
+    description:
+      'Retained earnings tracks net income from previous fiscal years.',
     active: 1,
     index: 1,
     predefined: 1,
@@ -165,7 +169,8 @@ export default [
     slug: 'opening-balance-equity',
     account_type: 'equity',
     code: '30002',
-    description:'When you enter opening balances to the accounts, the amounts enter in Opening balance equity. This ensures that you have a correct trial balance sheet for your company, without even specific the second credit or debit entry.',
+    description:
+      'When you enter opening balances to the accounts, the amounts enter in Opening balance equity. This ensures that you have a correct trial balance sheet for your company, without even specific the second credit or debit entry.',
     active: 1,
     index: 1,
     predefined: 1,
@@ -185,7 +190,8 @@ export default [
     slug: 'drawings',
     account_type: 'equity',
     code: '30003',
-    description:'Goods purchased with the intention of selling these to customers',
+    description:
+      'Goods purchased with the intention of selling these to customers',
     active: 1,
     index: 1,
     predefined: 1,
@@ -253,7 +259,8 @@ export default [
     account_type: 'expense',
     parent_account_id: null,
     code: '40006',
-    description: 'Any bank fees levied is recorded into the bank fees and charges account. A bank account maintenance fee, transaction charges, a late payment fee are some examples.',
+    description:
+      'Any bank fees levied is recorded into the bank fees and charges account. A bank account maintenance fee, transaction charges, a late payment fee are some examples.',
     active: 1,
     index: 1,
     predefined: 0,
@@ -310,9 +317,10 @@ export default [
     account_type: 'other-income',
     parent_account_id: null,
     code: '50004',
-    description:'The income activities are not associated to the core business.',
+    description:
+      'The income activities are not associated to the core business.',
     active: 1,
     index: 1,
     predefined: 0,
-  }
+  },
 ];

packages/server/src/interfaces/Item.ts

@@ -54,6 +54,14 @@ export interface IItemDTO {
   sellDescription: string;
   purchaseDescription: string;
 
+  // Used as an override if the default Tax Code for the selected `costAccountId` is not correct
+  purchaseTaxCode: string;
+  purchaseTaxId: string;
+
+  // Used as an override if the default Tax Code for the selected `sellAccountId` is not correct
+  saleTaxCode: string;
+  saleTaxId: string;
+
   quantityOnHand: number;
 
   note: string;

packages/server/src/interfaces/ItemEntry.ts

@@ -34,6 +34,7 @@ export interface IItemEntry {
 
   taxCode: string;
   taxRate: number;
+  taxAmount: number;
 
   item?: IItem;
 

packages/server/src/interfaces/SaleEstimate.ts

@@ -1,5 +1,5 @@
 import { Knex } from 'knex';
-import { IItemEntry } from './ItemEntry';
+import { IItemEntry, IItemEntryDTO } from './ItemEntry';
 import { IDynamicListFilterDTO } from '@/interfaces/DynamicFilter';
 
 export interface ISaleEstimate {
@@ -29,7 +29,7 @@ export interface ISaleEstimateDTO {
   estimateDate?: Date;
   reference?: string;
   estimateNumber?: string;
-  entries: IItemEntry[];
+  entries: IItemEntryDTO[];
   note: string;
   termsConditions: string;
   sendToEmail: string;

packages/server/src/interfaces/SaleInvoice.ts

@@ -1,5 +1,5 @@
 import { Knex } from 'knex';
-import { ISystemUser, IAccount } from '@/interfaces';
+import { ISystemUser, IAccount, ITaxTransaction } from '@/interfaces';
 import { IDynamicListFilter } from '@/interfaces/DynamicFilter';
 import { IItemEntry, IItemEntryDTO } from './ItemEntry';
 
@@ -33,6 +33,9 @@ export interface ISaleInvoice {
   writtenoffExpenseAccountId?: number;
 
   writtenoffExpenseAccount?: IAccount;
+
+  taxAmountWithheld: number;
+  taxes: ITaxTransaction[]
 }
 
 export interface ISaleInvoiceDTO {

packages/server/src/interfaces/TaxRate.ts

@@ -47,3 +47,10 @@ export interface ITaxRateDeletedPayload {
   tenantId: number;
   trx: Knex.Transaction;
 }
+
+
+export interface ITaxTransaction {
+  taxAmount: number;
+  taxName: string;
+  taxCode: string;
+}

packages/server/src/loaders/eventEmitter.ts

@@ -81,6 +81,9 @@ import { ProjectBillableExpensesSubscriber } from '@/services/Projects/Projects/
 import { ProjectBillableBillSubscriber } from '@/services/Projects/Projects/ProjectBillableBillSubscriber';
 import { SyncActualTimeTaskSubscriber } from '@/services/Projects/Times/SyncActualTimeTaskSubscriber';
 import { SaleInvoiceTaxRateValidateSubscriber } from '@/services/TaxRates/subscribers/SaleInvoiceTaxRateValidateSubscriber';
+import { SaleEstimateTaxRateValidateSubscriber } from '@/services/TaxRates/subscribers/SaleEstimateTaxRateValidateSubscriber';
+import { SaleReceiptTaxRateValidateSubscriber } from '@/services/TaxRates/subscribers/SaleReceiptTaxRateValidateSubscriber';
+import { WriteInvoiceTaxTransactionsSubscriber } from '@/services/TaxRates/subscribers/WriteInvoiceTaxTransactionsSubscriber';
 
 export default () => {
   return new EventPublisher();
@@ -188,6 +191,11 @@ export const susbcribers = () => {
     ProjectBillableTasksSubscriber,
     ProjectBillableExpensesSubscriber,
     ProjectBillableBillSubscriber,
-    SaleInvoiceTaxRateValidateSubscriber
+
+    // Tax Rates
+    SaleInvoiceTaxRateValidateSubscriber,
+    SaleEstimateTaxRateValidateSubscriber,
+    SaleReceiptTaxRateValidateSubscriber,
+    WriteInvoiceTaxTransactionsSubscriber
   ];
 };

packages/server/src/loaders/tenantModels.ts

@@ -59,6 +59,7 @@ import Project from 'models/Project';
 import Time from 'models/Time';
 import Task from 'models/Task';
 import TaxRate from 'models/TaxRate';
+import TaxRateTransaction from 'models/TaxRateTransaction';
 
 export default (knex) => {
   const models = {
@@ -121,6 +122,7 @@ export default (knex) => {
     Time,
     Task,
     TaxRate,
+    TaxRateTransaction,
   };
   return mapValues(models, (model) => model.bindKnex(knex));
 };

packages/server/src/models/ItemEntry.ts

@@ -2,6 +2,8 @@ import { Model } from 'objection';
 import TenantModel from 'models/TenantModel';
 
 export default class ItemEntry extends TenantModel {
+  public taxRate: number;
+
   /**
    * Table name.
    */
@@ -17,7 +19,7 @@ export default class ItemEntry extends TenantModel {
   }
 
   static get virtualAttributes() {
-    return ['amount'];
+    return ['amount', 'taxAmount'];
   }
 
   get amount() {
@@ -31,6 +33,22 @@ export default class ItemEntry extends TenantModel {
     return discount ? total - total * discount * 0.01 : total;
   }
 
+  /**
+   * Tag rate fraction.
+   * @returns {number}
+   */
+  get tagRateFraction() {
+    return this.taxRate / 100;
+  }
+
+  /**
+   * Tax amount withheld.
+   * @returns {number}
+   */
+  get taxAmount() {
+    return this.amount * this.tagRateFraction;
+  }
+
   static get relationMappings() {
     const Item = require('models/Item');
     const BillLandedCostEntry = require('models/BillLandedCostEntry');

packages/server/src/models/SaleInvoice.ts

@@ -13,6 +13,11 @@ export default class SaleInvoice extends mixin(TenantModel, [
   CustomViewBaseModel,
   ModelSearchable,
 ]) {
+  taxAmountWithheld: number;
+  balance: number;
+  paymentAmount: number;
+  exchangeRate: number;
+
   /**
    * Table name
    */
@@ -51,12 +56,115 @@ export default class SaleInvoice extends mixin(TenantModel, [
     ];
   }
 
+  /**
+   * Invoice total FCY.
+   * @returns {number}
+   */
+  get totalFcy() {
+    return this.amountFcy + this.taxAmountWithheldFcy;
+  }
+
+  /**
+   * Invoice total BCY.
+   * @returns {number}
+   */
+  get totalBcy() {
+    return this.amountBcy + this.taxAmountWithheldBcy;
+  }
+
+  /**
+   * Tax amount withheld FCY.
+   * @returns {number}
+   */
+  get taxAmountWithheldFcy() {
+    return this.taxAmountWithheld;
+  }
+
+  /**
+   * Tax amount withheld BCY.
+   * @returns {number}
+   */
+  get taxAmountWithheldBcy() {
+    return this.taxAmountWithheld;
+  }
+
+  /**
+   * Subtotal FCY.
+   * @returns {number}
+   */
+  get subtotalFcy() {
+    return this.amountFcy;
+  }
+
+  /**
+   * Subtotal BCY.
+   * @returns {number}
+   */
+  get subtotalBcy() {
+    return this.amountBcy;
+  }
+
+  /**
+   * Invoice due amount FCY.
+   * @returns {number}
+   */
+  get dueAmountFcy() {
+    return this.amountFcy - this.paymentAmountFcy;
+  }
+
+  /**
+   * Invoice due amount BCY.
+   * @returns {number}
+   */
+  get dueAmountBcy() {
+    return this.amountBcy - this.paymentAmountBcy;
+  }
+
+  /**
+   * Invoice amount FCY.
+   * @returns {number}
+   */
+  get amountFcy() {
+    return this.balance;
+  }
+
+  /**
+   * Invoice amount BCY.
+   * @returns {number}
+   */
+  get amountBcy() {
+    return this.balance * this.exchangeRate;
+  }
+
+  /**
+   * Invoice payment amount FCY.
+   * @returns {number}
+   */
+  get paymentAmountFcy() {
+    return this.paymentAmount;
+  }
+
+  /**
+   * Invoice payment amount BCY.
+   * @returns {number}
+   */
+  get paymentAmountBcy() {
+    return this.paymentAmount * this.exchangeRate;
+  }
+
+  /**
+   *
+   */
+  get total() {
+    return this.balance + this.taxAmountWithheld;
+  }
+
   /**
    * Invoice amount in local currency.
    * @returns {number}
    */
   get localAmount() {
-    return this.balance * this.exchangeRate;
+    return this.total * this.exchangeRate;
   }
 
   /**
@@ -333,6 +441,7 @@ export default class SaleInvoice extends mixin(TenantModel, [
     const PaymentReceiveEntry = require('models/PaymentReceiveEntry');
     const Branch = require('models/Branch');
     const Account = require('models/Account');
+    const TaxRateTransaction = require('models/TaxRateTransaction');
 
     return {
       /**
@@ -428,6 +537,21 @@ export default class SaleInvoice extends mixin(TenantModel, [
           to: 'accounts.id',
         },
       },
+
+      /**
+       *
+       */
+      taxes: {
+        relation: Model.HasManyRelation,
+        modelClass: TaxRateTransaction.default,
+        join: {
+          from: 'sales_invoices.id',
+          to: 'tax_rate_transactions.referenceId',
+        },
+        filter(builder) {
+          builder.where('reference_type', 'SaleInvoice');
+        },
+      },
     };
   }
 

packages/server/src/models/TaxRateTransaction.ts

@@ -0,0 +1,42 @@
+import { mixin, Model, raw } from 'objection';
+import TenantModel from 'models/TenantModel';
+import ModelSearchable from './ModelSearchable';
+
+export default class TaxRateTransaction extends mixin(TenantModel, [
+  ModelSearchable,
+]) {
+  /**
+   * Table name
+   */
+  static get tableName() {
+    return 'tax_rate_transactions';
+  }
+
+  /**
+   * Timestamps columns.
+   */
+  get timestamps() {
+    return [];
+  }
+
+  /**
+   * Virtual attributes.
+   */
+  static get virtualAttributes() {
+    return [];
+  }
+
+  /**
+   * Model modifiers.
+   */
+  static get modifiers() {
+    return {};
+  }
+
+  /**
+   * Relationship mapping.
+   */
+  static get relationMappings() {
+    return {};
+  }
+}

packages/server/src/repositories/AccountRepository.ts

@@ -2,6 +2,7 @@ import { Account } from 'models';
 import TenantRepository from '@/repositories/TenantRepository';
 import { IAccount } from '@/interfaces';
 import { Knex } from 'knex';
+import { TaxPayableAccount } from '@/database/seeds/data/accounts';
 
 export default class AccountRepository extends TenantRepository {
   /**
@@ -116,7 +117,7 @@ export default class AccountRepository extends TenantRepository {
     if (!result) {
       result = await this.model.query(trx).insertAndFetch({
         name: this.i18n.__('account.accounts_receivable.currency', {
-          currency: currencyCode
+          currency: currencyCode,
         }),
         accountType: 'accounts-receivable',
         currencyCode,
@@ -127,6 +128,29 @@ export default class AccountRepository extends TenantRepository {
     return result;
   };
 
+  /**
+   * Find or create tax payable account.
+   * @param {Record<string, string>}extraAttrs
+   * @param {Knex.Transaction} trx
+   * @returns
+   */
+  async findOrCreateTaxPayable(
+    extraAttrs: Record<string, string> = {},
+    trx?: Knex.Transaction
+  ) {
+    let result = await this.model
+      .query(trx)
+      .findOne({ slug: TaxPayableAccount.slug, ...extraAttrs });
+
+    if (!result) {
+      result = await this.model.query(trx).insertAndFetch({
+        ...TaxPayableAccount,
+        ...extraAttrs,
+      });
+    }
+    return result;
+  }
+
   findOrCreateAccountsPayable = async (
     currencyCode: string = '',
     extraAttrs = {},

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

@@ -17,6 +17,7 @@ import HasTenancyService from '@/services/Tenancy/TenancyService';
 import { CommandSaleInvoiceValidators } from './CommandSaleInvoiceValidators';
 import { SaleInvoiceIncrement } from './SaleInvoiceIncrement';
 import { formatDateFields } from 'utils';
+import { ItemEntriesTaxTransactions } from '@/services/TaxRates/ItemEntriesTaxTransactions';
 
 @Service()
 export class CommandSaleInvoiceDTOTransformer {
@@ -38,6 +39,9 @@ export class CommandSaleInvoiceDTOTransformer {
   @Inject()
   private invoiceIncrement: SaleInvoiceIncrement;
 
+  @Inject()
+  private taxDTOTransformer: ItemEntriesTaxTransactions;
+
   /**
    * Transformes the create DTO to invoice object model.
    * @param {ISaleInvoiceCreateDTO} saleInvoiceDTO - Sale invoice DTO.
@@ -96,6 +100,7 @@ export class CommandSaleInvoiceDTOTransformer {
     } as ISaleInvoice;
 
     return R.compose(
+      this.taxDTOTransformer.assocTaxAmountWithheldFromEntries,
       this.branchDTOTransform.transformDTO<ISaleInvoice>(tenantId),
       this.warehouseDTOTransform.transformDTO<ISaleInvoice>(tenantId)
     )(initialDTO);

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

@@ -1,12 +1,13 @@
 import * as R from 'ramda';
+import { Knex } from 'knex';
 import {
   ISaleInvoice,
   IItemEntry,
   ILedgerEntry,
   AccountNormal,
   ILedger,
+  ITaxTransaction,
 } from '@/interfaces';
-import { Knex } from 'knex';
 import { Service, Inject } from 'typedi';
 import Ledger from '@/services/Accounting/Ledger';
 import LedgerStorageService from '@/services/Accounting/LedgerStorageService';
@@ -22,8 +23,8 @@ export class SaleInvoiceGLEntries {
 
   /**
    * Writes a sale invoice GL entries.
-   * @param {number} tenantId
-   * @param {number} saleInvoiceId
+   * @param {number} tenantId - Tenant id.
+   * @param {number} saleInvoiceId - Sale invoice id.
    * @param {Knex.Transaction} trx
    */
   public writeInvoiceGLEntries = async (
@@ -42,9 +43,17 @@ export class SaleInvoiceGLEntries {
     const ARAccount = await accountRepository.findOrCreateAccountReceivable(
       saleInvoice.currencyCode
     );
+    // Find or create tax payable account.
+    const taxPayableAccount = await accountRepository.findOrCreateTaxPayable(
+      {},
+      trx
+    );
     // Retrieves the ledger of the invoice.
-    const ledger = this.getInvoiceGLedger(saleInvoice, ARAccount.id);
-
+    const ledger = this.getInvoiceGLedger(
+      saleInvoice,
+      ARAccount.id,
+      taxPayableAccount.id
+    );
     // Commits the ledger entries to the storage as UOW.
     await this.ledegrRepository.commit(tenantId, ledger, trx);
   };
@@ -94,10 +103,14 @@ export class SaleInvoiceGLEntries {
    */
   public getInvoiceGLedger = (
     saleInvoice: ISaleInvoice,
-    ARAccountId: number
+    ARAccountId: number,
+    taxPayableAccountId: number
   ): ILedger => {
-    const entries = this.getInvoiceGLEntries(saleInvoice, ARAccountId);
-
+    const entries = this.getInvoiceGLEntries(
+      saleInvoice,
+      ARAccountId,
+      taxPayableAccountId
+    );
     return new Ledger(entries);
   };
 
@@ -143,7 +156,7 @@ export class SaleInvoiceGLEntries {
 
     return {
       ...commonEntry,
-      debit: saleInvoice.localAmount,
+      debit: saleInvoice.totalBcy,
       accountId: ARAccountId,
       contactId: saleInvoice.customerId,
       accountNormal: AccountNormal.DEBIT,
@@ -176,7 +189,27 @@ export class SaleInvoiceGLEntries {
         itemId: entry.itemId,
         itemQuantity: entry.quantity,
         accountNormal: AccountNormal.CREDIT,
-        projectId: entry.projectId || saleInvoice.projectId
+        projectId: entry.projectId || saleInvoice.projectId,
+      };
+    }
+  );
+
+  /**
+   * Retreives the GL entry of tax payable.
+   * @param {ISaleInvoice} saleInvoice -
+   * @param {number} taxPayableAccountId -
+   * @returns {ILedgerEntry}
+   */
+  private getInvoiceTaxEntry = R.curry(
+    (saleInvoice: ISaleInvoice, taxPayableAccountId: number): ILedgerEntry => {
+      const commonEntry = this.getInvoiceGLCommonEntry(saleInvoice);
+
+      return {
+        ...commonEntry,
+        credit: saleInvoice.taxAmountWithheld,
+        accountId: taxPayableAccountId,
+        index: saleInvoice.entries.length + 3,
+        accountNormal: AccountNormal.CREDIT,
       };
     }
   );
@@ -189,15 +222,18 @@ export class SaleInvoiceGLEntries {
    */
   public getInvoiceGLEntries = (
     saleInvoice: ISaleInvoice,
-    ARAccountId: number
+    ARAccountId: number,
+    taxPayableAccountId: number
   ): ILedgerEntry[] => {
     const receivableEntry = this.getInvoiceReceivableEntry(
       saleInvoice,
       ARAccountId
     );
     const transformItemEntry = this.getInvoiceItemEntry(saleInvoice);
-    const creditEntries = saleInvoice.entries.map(transformItemEntry);
 
-    return [receivableEntry, ...creditEntries];
+    const creditEntries = saleInvoice.entries.map(transformItemEntry);
+    const taxEntry = this.getInvoiceTaxEntry(saleInvoice, taxPayableAccountId);
+
+    return [receivableEntry, ...creditEntries, taxEntry];
   };
 }

packages/server/src/services/TaxRates/ItemEntriesTaxTransactions.ts

@@ -0,0 +1,22 @@
+import { ItemEntry } from "@/models";
+import { sumBy } from "lodash";
+import { Service } from "typedi";
+
+
+@Service()
+export class ItemEntriesTaxTransactions {
+  /**
+   * 
+   * @param model 
+   * @returns 
+   */
+  public assocTaxAmountWithheldFromEntries(model: any) {
+    const entries = model.entries.map((entry) => ItemEntry.fromJson(entry));
+    const taxAmountWithheld = sumBy(entries, 'taxAmount');
+
+    if (taxAmountWithheld) {
+      model.taxAmountWithheld = taxAmountWithheld;
+    }
+    return model;
+  }
+}

packages/server/src/services/TaxRates/WriteTaxTransactionsItemEntries.ts

@@ -0,0 +1,65 @@
+import { sumBy, chain } from 'lodash';
+import { IItemEntry } from '@/interfaces';
+import HasTenancyService from '../Tenancy/TenancyService';
+import { Inject, Service } from 'typedi';
+
+@Service()
+export class WriteTaxTransactionsItemEntries {
+  @Inject()
+  private tenancy: HasTenancyService;
+
+  /**
+   * Writes the tax transactions from the given item entries.
+   * @param {number} tenantId
+   * @param {IItemEntry[]} itemEntries
+   */
+  public async writeTaxTransactionsFromItemEntries(
+    tenantId: number,
+    itemEntries: IItemEntry[]
+  ) {
+    const { TaxRateTransaction } = this.tenancy.models(tenantId);
+    const aggregatedEntries = this.aggregateItemEntriesByTaxCode(itemEntries);
+
+    const taxTransactions = aggregatedEntries.map((entry) => ({
+      taxName: 'TAX NAME',
+      taxCode: 'TAG_CODE',
+      referenceType: entry.referenceType,
+      referenceId: entry.referenceId,
+      taxAmount: entry.taxAmount,
+    }));
+    await TaxRateTransaction.query().upsertGraph(taxTransactions);
+  }
+
+  /**
+   * 
+   * @param {IItemEntry[]} itemEntries
+   * @returns {}
+   */
+  private aggregateItemEntriesByTaxCode(itemEntries: IItemEntry[]) {
+    return chain(itemEntries.filter((item) => item.taxCode))
+      .groupBy((item) => item.taxCode)
+      .values()
+      .map((group) => ({ ...group[0], amount: sumBy(group, 'amount') }))
+      .value();
+  }
+
+  /**
+   * 
+   * @param itemEntries
+   */
+  private aggregateItemEntriesByReferenceTypeId(itemEntries: IItemEntry) {}
+
+  /**
+   * Removes the tax transactions from the given item entries.
+   * @param tenantId
+   * @param itemEntries
+   */
+  public removeTaxTransactionsFromItemEntries(
+    tenantId: number,
+    itemEntries: IItemEntry[]
+  ) {
+    const { TaxRateTransaction } = this.tenancy.models(tenantId);
+
+    const filteredEntries = itemEntries.filter((item) => item.taxCode);
+  }
+}

packages/server/src/services/TaxRates/subscribers/WriteInvoiceTaxTransactionsSubscriber.ts

@@ -0,0 +1,56 @@
+import { Inject, Service } from 'typedi';
+import {
+  ISaleInvoiceCreatedPayload,
+  ISaleInvoiceDeletedPayload,
+} from '@/interfaces';
+import events from '@/subscribers/events';
+import { WriteTaxTransactionsItemEntries } from '../WriteTaxTransactionsItemEntries';
+
+@Service()
+export class WriteInvoiceTaxTransactionsSubscriber {
+  @Inject()
+  private writeTaxTransactions: WriteTaxTransactionsItemEntries;
+
+  /**
+   * Attaches events with handlers.
+   */
+  public attach(bus) {
+    bus.subscribe(
+      events.saleInvoice.onCreated,
+      this.writeInvoiceTaxTransactionsOnCreated
+    );
+    bus.subscribe(
+      events.saleInvoice.onDeleted,
+      this.removeInvoiceTaxTransactionsOnDeleted
+    );
+    return bus;
+  }
+
+  /**
+   * Validate receipt entries tax rate code existance.
+   * @param {ISaleInvoiceCreatingPaylaod}
+   */
+  private writeInvoiceTaxTransactionsOnCreated = async ({
+    tenantId,
+    saleInvoice,
+  }: ISaleInvoiceCreatedPayload) => {
+    await this.writeTaxTransactions.writeTaxTransactionsFromItemEntries(
+      tenantId,
+      saleInvoice.entries
+    );
+  };
+
+  /**
+   * Removes the invoice tax transactions on invoice deleted.
+   * @param {ISaleInvoiceEditingPayload}
+   */
+  private removeInvoiceTaxTransactionsOnDeleted = async ({
+    tenantId,
+    oldSaleInvoice,
+  }: ISaleInvoiceDeletedPayload) => {
+    await this.writeTaxTransactions.removeTaxTransactionsFromItemEntries(
+      tenantId,
+      oldSaleInvoice.entries
+    );
+  };
+}