feat: auto-increment invoices.

server/src/services/Sales/AutoIncrementOrdersService.ts

@@ -0,0 +1,71 @@
+import { Service, Inject } from 'typedi';
+import TenancyService from 'services/Tenancy/TenancyService';
+import { transactionIncrement } from 'utils';
+
+/**
+ * Auto increment orders service.
+ */
+@Service()
+export default class AutoIncrementOrdersService {
+  @Inject()
+  tenancy: TenancyService;
+
+  /**
+   * Retrieve the next service transaction number.
+   * @param {number} tenantId
+   * @param {string} settingsGroup
+   * @param {Function} getMaxTransactionNo
+   * @return {Promise<[string, string]>}
+   */
+  async getNextTransactionNumber(
+    tenantId: number,
+    settingsGroup: string,
+    getOrderTransaction: (prefix: string, number: string) => Promise<boolean>,
+    getMaxTransactionNumber: (prefix: string, number: string) => Promise<string>
+  ): Promise<[string, string]> {
+    const settings = this.tenancy.settings(tenantId);
+    const group = settingsGroup;
+
+    // Settings service transaction number and prefix.
+    const settingNo = settings.get({ group, key: 'next_number' });
+    const settingPrefix = settings.get({ group, key: 'number_prefix' });
+
+    let nextInvoiceNumber = settingNo;
+
+    const orderTransaction = await getOrderTransaction(
+      settingPrefix,
+      settingNo
+    );
+    if (orderTransaction) {
+      // Retrieve the max invoice number in the given prefix.
+      const maxInvoiceNo = await getMaxTransactionNumber(
+        settingPrefix,
+        settingNo
+      );
+      if (maxInvoiceNo) {
+        nextInvoiceNumber = transactionIncrement(maxInvoiceNo);
+      }
+    }
+    return [settingPrefix, nextInvoiceNumber];
+  }
+
+  /**
+   * Increment setting next number.
+   * @param {number} tenantId -
+   * @param {string} orderGroup - Order group.
+   * @param {string} orderNumber -Order number.
+   */
+  async incrementSettingsNextNumber(
+    tenantId,
+    orderGroup: string,
+    orderNumber: string
+  ) {
+    const settings = this.tenancy.settings(tenantId);
+
+    settings.set(
+      { group: orderGroup, key: 'next_number' },
+      transactionIncrement(orderNumber)
+    );
+    await settings.save();
+  }
+}