Fix re-processing REPLACED charge versions

app/services/supplementary-billing/fetch-charge-versions.service.js

@@ -1,25 +1,23 @@
 'use strict'
 
-const { ref } = require('objection')
 /**
- * Fetches SROC charge versions that might be included in a supplementary bill run
+ * Fetches SROC charge versions linked to licences flagged for inclusion in next SROC supplementary billing
  * @module FetchChargeVersionsService
  */
 
+const { ref } = require('objection')
+
 const ChargeVersion = require('../../models/water/charge-version.model.js')
 const ChargeVersionWorkflow = require('../../models/water/charge-version-workflow.model.js')
 
 /**
- * Fetch all 'current' SROC charge versions linked to licences flagged for supplementary billing that are in the period
- * being billed
- *
- * > This is not the final form of the service. It is a 'work in progress' as we implement tickets that gradually
- * > build up our understanding of SROC supplementary billing
+ * Fetch all SROC charge versions linked to licences flagged for supplementary billing that are in the period being
+ * billed
  *
- * @param {string} regionId GUID of the region which the licences will be linked to
+ * @param {string} regionId UUID of the region being billed that the licences must be linked to
  * @param {Object} billingPeriod Object with a `startDate` and `endDate` property representing the period being billed
  *
- * @returns an array of Objects containing the relevant charge versions
+ * @returns {Object[]} an array of matching charge versions
  */
 async function go (regionId, billingPeriod) {
   const chargeVersions = await _fetch(regionId, billingPeriod)
@@ -34,16 +32,17 @@ async function _fetch (regionId, billingPeriod) {
       'scheme',
       'chargeVersions.startDate',
       'chargeVersions.endDate',
-      'invoiceAccountId'
+      'invoiceAccountId',
+      'status'
     ])
     .innerJoinRelated('licence')
-    .where('scheme', 'sroc')
-    .whereNotNull('invoiceAccountId')
     .where('includeInSrocSupplementaryBilling', true)
     .where('regionId', regionId)
-    .where('chargeVersions.status', 'current')
+    .where('chargeVersions.scheme', 'sroc')
+    .whereNotNull('chargeVersions.invoiceAccountId')
     .where('chargeVersions.startDate', '>=', billingPeriod.startDate)
     .where('chargeVersions.startDate', '<=', billingPeriod.endDate)
+    .whereNot('chargeVersions.status', 'draft')
     .whereNotExists(
       ChargeVersionWorkflow.query()
         .select(1)

app/services/supplementary-billing/process-billing-batch.service.js

@@ -22,7 +22,6 @@ const HandleErroredBillingBatchService = require('./handle-errored-billing-batch
 const LegacyRequestLib = require('../../lib/legacy-request.lib.js')
 const LicenceModel = require('../../models/water/licence.model.js')
 const ProcessBillingTransactionsService = require('./process-billing-transactions.service.js')
-const ProcessReplacedChargeVersionsService = require('./process-replaced-charge-versions.service.js')
 
 /**
  * Creates the invoices and transactions in both WRLS and the Charging Module API
@@ -73,13 +72,18 @@ async function go (billingBatch, billingPeriod) {
       currentBillingData.billingInvoice = billingInvoice
       currentBillingData.billingInvoiceLicence = billingInvoiceLicence
 
-      const calculatedTransactions = _generateCalculatedTransactions(billingPeriod, chargeVersion, billingBatchId, billingInvoiceLicence)
-      currentBillingData.calculatedTransactions.push(...calculatedTransactions)
+      // If the charge version has a status of 'current' (APPROVED) then it is likely to be something we have never
+      // billed previously so we need to calculate a debit line.
+      // Else the charge version has been 'superseded' (REPLACED). So, we won't be adding a new debit line to the bill
+      // for it. But we still need to process it to understand what, if anything, needs to be credited back or if our
+      // calculated debit line has already been billed.
+      if (chargeVersion.status === 'current') {
+        const calculatedTransactions = _generateCalculatedTransactions(billingPeriod, chargeVersion, billingBatchId, billingInvoiceLicence)
+        currentBillingData.calculatedTransactions.push(...calculatedTransactions)
+      }
     }
     await _finaliseCurrentInvoiceLicence(currentBillingData, billingPeriod, billingBatch)
 
-    await _processReplacedChargeVersions(currentBillingData, billingBatch, billingPeriod)
-
     await _finaliseBillingBatch(billingBatch, chargeVersions, currentBillingData.isEmpty)
 
     // Log how long the process took
@@ -285,19 +289,6 @@ function _logError (billingBatch, error) {
     })
 }
 
-async function _processReplacedChargeVersions (currentBillingData, billingBatch, billingPeriod) {
-  try {
-    const anythingGenerated = await ProcessReplacedChargeVersionsService.go(billingBatch, billingPeriod)
-    if (anythingGenerated) {
-      currentBillingData.isEmpty = false
-    }
-  } catch (error) {
-    HandleErroredBillingBatchService.go(billingBatch.billingBatchId)
-
-    throw error
-  }
-}
-
 async function _updateStatus (billingBatchId, status) {
   try {
     await BillingBatchModel.query()