add create user and login user parts

app/utils/users/createBusinessCustomer.util.js

@@ -0,0 +1,86 @@
+// app/utils/users/createBusinessCustomer.util.js 
+
+const db = require("../../models");
+
+const {
+  generateBusinessCustomerId,
+} = require("../idGen.util");
+
+const BusinessCustomer = db.BusinessCustomer;
+
+
+/**
+ * Create business-customer-specific details
+ */
+const createBusinessCustomerDetails = async (
+  userId,
+  businessData,
+  transaction
+) => {
+
+  const {
+    businessName,
+    businessRegistrationNumber,
+    businessType,
+    contactName,
+    phoneNumber,
+    businessEmail,
+    expectedMonthlyVolume,
+    note,
+  } = businessData;
+
+
+  if (
+    !businessName ||
+    !businessRegistrationNumber ||
+    !businessType ||
+    !contactName ||
+    !phoneNumber ||
+    !businessEmail ||
+    !expectedMonthlyVolume
+  ) {
+    throw new Error(
+      "Required business customer details are missing"
+    );
+  }
+
+
+  const businessCustomer =
+    await BusinessCustomer.create(
+      {
+        business_customer_id:
+          generateBusinessCustomerId(),
+
+        user_id:
+          userId,
+
+        businessName,
+
+        businessRegistrationNumber,
+
+        businessType,
+
+        contactName,
+
+        phoneNumber,
+
+        businessEmail,
+
+        expectedMonthlyVolume,
+
+        note:
+          note || null,
+      },
+      {
+        transaction,
+      }
+    );
+
+
+  return businessCustomer;
+};
+
+
+module.exports = {
+  createBusinessCustomerDetails,
+};