Provide customer's daily volume

Provide customer's info on sms phone code

lib/customers.js

@@ -0,0 +1,35 @@
+const db = require('./db')
+const uuid = require('uuid')
+const _ = require('lodash/fp')
+const BN = require('./bn')
+
+function add (customer) {
+  const sql = 'insert into customers (id, phone, phone_at) values ($1, $2, now()) returning *'
+  return db.one(sql, [uuid.v4(), customer.phone])
+}
+
+function get (phone) {
+  const sql = 'select id, phone from customers where phone=$1'
+  return db.oneOrNone(sql, [phone])
+  .then(customer => {
+    if (!customer) return
+    return getDailyVolume(customer.id).then(dailyVolume => {
+      return _.set('dailyVolume', dailyVolume, customer)
+    })
+  })
+}
+
+function getDailyVolume (id) {
+  return Promise.all([
+    db.one(`select coalesce(sum(fiat), 0) as total from cash_in_txs 
+           where customer_id=$1 
+           and created > now() - interval '1 day'`, [id]),
+    db.one(`select COALESCE(sum(fiat), 0) as total from cash_out_txs 
+           where customer_id=$1 
+           and created > now() - interval '1 day'`, [id])
+  ]).then(([cashInTotal, cashOutTotal]) => {
+    return BN(cashInTotal.total).add(cashOutTotal.total)
+  })
+}
+
+module.exports = { add, get }