refactor: simplify bills query building

packages/server/lib/new-admin/services/bills.js

@@ -3,39 +3,42 @@ const pgp = require('pg-promise')()
 
 const db = require('../../db')
 
-const getBills = filters => {
-  const deviceStatement = !_.isNil(filters.deviceId)
-    ? `WHERE device_id = ${pgp.as.text(filters.deviceId)}`
-    : ``
-  const batchStatement = filter => {
-    switch (filter) {
-      case 'none':
-        return `WHERE b.cashbox_batch_id IS NULL`
-      case 'any':
-        return `WHERE b.cashbox_batch_id IS NOT NULL`
-      default:
-        return _.isNil(filter)
-          ? ``
-          : `WHERE b.cashbox_batch_id = ${pgp.as.text(filter)}`
-    }
+const WHERE = conds => (conds ? 'WHERE ' + conds : '')
+
+const AND = (...clauses) => clauses.filter(clause => !!clause).join(' AND ')
+
+const getBatchIDCondition = filter => {
+  switch (filter) {
+    case 'none':
+      return 'b.cashbox_batch_id IS NULL'
+    case 'any':
+      return 'b.cashbox_batch_id IS NOT NULL'
+    default:
+      return _.isNil(filter)
+        ? ''
+        : `b.cashbox_batch_id = ${pgp.as.text(filter)}`
   }
+}
+
+const getBills = filters => {
+  const deviceIDCondition = !_.isNil(filters.deviceId)
+    ? `device_id = ${pgp.as.text(filters.deviceId)}`
+    : ''
+  const batchIDCondition = getBatchIDCondition(filters.batch)
 
   const sql = `SELECT b.id, b.fiat, b.fiat_code, b.created, b.cashbox_batch_id, cit.device_id AS device_id
   FROM bills b
   LEFT OUTER JOIN (
     SELECT id, device_id
     FROM cash_in_txs
-    ${deviceStatement}
+    WHERE ${AND(deviceIDCondition)}
   ) AS cit
   ON cit.id = b.cash_in_txs_id
-  ${batchStatement(filters.batch)}
-  ${_.isNil(batchStatement(filters.batch)) ? `WHERE` : `AND`}
-  b.destination_unit = 'cashbox'`
+  WHERE ${AND(batchIDCondition, "b.destination_unit = 'cashbox'")}`
 
   const sql2 = `SELECT b.id, b.fiat, b.fiat_code, b.created, b.cashbox_batch_id, b.device_id
   FROM empty_unit_bills b
-  ${deviceStatement}
-  ${!_.isNil(filters.deviceId) && !_.isNil(filters.batch) ? `AND ${_.replace('WHERE', '', batchStatement(filters.batch))}` : `${batchStatement(filters.batch)}`}`
+  ${WHERE(AND(deviceIDCondition, batchIDCondition))}`
 
   return Promise.all([db.any(sql), db.any(sql2)]).then(
     ([bills, operationalBills]) =>