Coupon can be added to order

api/middleware/validators.js

@@ -40,6 +40,10 @@ validators.address = [
   body('zip').isString().isLength({min: 1}).withMessage('Postal code is required')
 ]
 
+validators.coupon = [
+  body('code').isString().isLength({min: 3, max: 50}).withMessage('Coupon code is required')
+]
+
 validators.handleApiError = (req, res, next) => {
   const errors = validationResult(req)
 

api/orders.js

@@ -33,3 +33,18 @@ router.post('/current/address', parseJSON, validate.address, validate.handleApiE
 
   res.json(order)
 })
+
+router.post('/current/coupon', parseJSON, validate.coupon, validate.handleApiError, async (req, res) => {
+  const origOrder = await db.order.findForCart(req.cart.uuid);
+  if(!origOrder) throw new Error("Unable to find current order");
+
+  const coupon = await db.coupon.find(req.body.code)
+
+  const currentTransaction = origOrder
+    .transactions.find(transaction => (
+      transaction.payment_state === 'started'
+    ))
+
+  const order = await db.order.addCoupon(currentTransaction, coupon)
+  res.json(order)
+})

components/form/input.js

@@ -2,13 +2,13 @@ import React from 'react'
 
 import styles from './styles.module.css'
 
-export default function Input({label: _label, error, hint, type, name, value, onChange, onBlur, isValid = true}){
+export default function Input({inputRef, label: _label, error, hint, type, name, value, onChange, onBlur, isValid = true}){
   const label = (_label === undefined) ? name.replace(name[0], name[0].toUpperCase()) : _label
 
   return (
     <div className={styles.formElementContainer}>
       {label && <label htmlFor={name}>{label}:</label>}
-      <input className={(isValid && !error)?'':styles.invalid} type={type} name={name} value={value} onChange={onChange} onBlur={onBlur} />
+      <input ref={inputRef} className={(isValid && !error)?'':styles.invalid} type={type} name={name} value={value} onChange={onChange} onBlur={onBlur} />
       {(hint || error) && <span className={styles.hint}>{error || (isValid ? '' : hint)}</span>}
     </div>
   )

db/index.js

@@ -6,5 +6,6 @@ module.exports = {
   session: require('./models/session'),
   cart: require('./models/cart'),
   order: require('./models/order'),
-  address: require('./models/address')
+  address: require('./models/address'),
+  coupon: require('./models/coupon')
 }

db/mappings/order.js

@@ -25,7 +25,8 @@ module.exports = [{
     'tax_price'
   ],
   associations: [
-    {name: 'cart', mapId: 'cartMap', columnPrefix: 'cart_'}
+    {name: 'cart', mapId: 'cartMap', columnPrefix: 'cart_'},
+    {name: 'coupon', mapId: 'couponMap', columnPrefix: 'coupon_'}
   ]
 },{
   mapId: 'addressMap',
@@ -42,4 +43,17 @@ module.exports = [{
     'phone',
     'easypost_id'
   ]
+},{
+  mapId: 'couponMap',
+  idProperty: 'uuid',
+  properties: [
+    'code',
+    'valid_until',
+    'free_shipping',
+    'number_allowed_uses',
+    'flat_discount_cents',
+    'percent_discount',
+    'per_sock_discount_cents',
+    'number_of_socks_free'
+  ]
 }]

db/models/coupon.js

@@ -0,0 +1,41 @@
+const pg = require('../pg')
+const joinjs = require('join-js').default;
+const debug = require('debug')('sos:db:coupon')
+const mappings = require('../mappings')
+
+const coupon = module.exports = {}
+
+coupon.create = async function(code, valid_until, free_shipping, number_allowed_uses, flat_discount_cents, percent_discount, per_sock_discount_cents, number_of_socks_free){
+  const query = {
+    text: 'select * from sos.create_coupon($1, $2, $3, $4, $5, $6, $7, $8)',
+    values: [
+      code,
+      valid_until,
+      free_shipping,
+      number_allowed_uses,
+      flat_discount_cents,
+      percent_discount,
+      per_sock_discount_cents,
+      number_of_socks_free
+    ]
+  }
+
+  debug(query)
+
+  const {rows} = await pg.query(query);
+  return joinjs.map(rows, mappings, 'couponMap', 'coupon_')[0]
+}
+
+coupon.find = async function(code){
+  const query = {
+    text: 'select * from sos.coupon where coupon_code = $1',
+    values: [
+      code
+    ]
+  }
+
+  debug(query)
+
+  const {rows} = await pg.query(query);
+  return joinjs.map(rows, mappings, 'couponMap', 'coupon_')[0]
+}

db/models/order.js

@@ -2,7 +2,9 @@ const pg = require('../pg')
 const joinjs = require('join-js').default;
 const debug = require('debug')('sos:db:order')
 const mappings = require('../mappings')
+const dbUtil = require('../util')
 
+const {DateTime} = require('luxon')
 const easypost = new (require('@easypost/api'))(process.env.EASYPOST_API_KEY);
 
 const order = module.exports = {}
@@ -77,3 +79,56 @@ order.addAddress = async function (transaction, address){
 
   return joinjs.map(rows, mappings, 'orderMap', 'order_')[0];
 }
+
+order.addCoupon = function(transaction, coupon) {
+  // Check coupon validity
+  const couponExpireTime = DateTime.fromJSDate(coupon.valid_until)
+  if(couponExpireTime.diffNow().as('seconds') < 0)
+    throw new Error("Coupon has expired");
+
+  const {item_total_price} = transaction
+  let discount = 0;
+
+  if(coupon.flat_discount_cents)
+    discount = coupon.flat_discount_cents;
+
+  if(coupon.percent_discount)
+    discount = Math.ceil(item_total_price * coupon.percent_discount / 100)
+
+  if(coupon.per_sock_discount_cents)
+    discount = transaction.cart.items
+      // For each item type, create an array of length n (number of items of that type in cart)
+      // where each index is initialized to the item price
+      .map(({item, count}) => new Array(count).fill(item.price_cents))
+      // Flatten to just be all prices
+      .flat()
+      // For each price, convert it to the per-item discount (max of item price)
+      .map(price => Math.min(price, coupon.per_sock_discount_cents))
+      // Sum all the discounts
+      .reduce((a,c) => (a+c))
+
+  if(coupon.number_of_socks_free)
+    discount = transaction.cart.items
+      // For each item type, create an array of length n (number of items of that type in cart)
+      // where each index is initialized to the item price
+      .map(({item, count}) => new Array(count).fill(item.price_cents))
+      // Flatten to just be all prices
+      .flat()
+      // Order so the most expensive are at the front
+      .sort((a,b) => (b-a))
+      // Keep only first n items
+      .slice(0, coupon.number_of_socks_free)
+      // Sum the item costs for total discount
+      .reduce((a,c) => (a+c))
+
+  return dbUtil.executeFunction({
+    name: 'add_coupon_to_transaction',
+    params: [
+      transaction.uuid,
+      coupon.uuid,
+      discount
+    ],
+    returnType: 'order',
+    single: true
+  })
+}

db/sql/1-tables.sql

@@ -156,7 +156,16 @@ create table sos."coupon" (
   coupon_flat_discount_cents      integer         not null default 0 check (coupon_flat_discount_cents >= 0),
   coupon_percent_discount         integer         not null default 0 check (coupon_percent_discount >= 0 and coupon_percent_discount <= 100),
   coupon_per_sock_discount_cents  integer         not null default 0 check (coupon_per_sock_discount_cents >= 0),
-  coupon_number_of_socks_free     integer         not null default 0 check (coupon_number_of_socks_free >= 0)
+  coupon_number_of_socks_free     integer         not null default 0 check (coupon_number_of_socks_free >= 0),
+
+  constraint only_one_coupon_discount check (
+    (
+      case when coupon_flat_discount_cents     = 0 then 0 else 1 end
+    + case when coupon_percent_discount        = 0 then 0 else 1 end
+    + case when coupon_per_sock_discount_cents = 0 then 0 else 1 end
+    + case when coupon_number_of_socks_free    = 0 then 0 else 1 end
+    ) < 2
+  )
 );
 
 create table sos."transaction" (

db/sql/2-views.sql

@@ -82,5 +82,6 @@ create or replace view sos.v_cart_price as
 create or replace view sos.v_order as
   select * from sos."order"
     left join sos."transaction" on transaction_order_uuid = order_uuid
+    left join sos."coupon" on transaction_coupon_uuid = coupon_uuid
     left join sos."address" on order_address_uuid = address_uuid
     left join sos.v_cart on cart_uuid = transaction_cart_uuid;

db/sql/3-functions.sql

@@ -573,3 +573,74 @@ begin
 
   return query select * from sos.v_order where order_uuid = _order_uuid;
 end; $function$;
+
+create or replace function sos.create_coupon(_code varchar(50), _valid_until timestamptz, _free_shipping boolean, _number_allowed_uses integer, _flat_discount_cents integer, _percent_discount integer, _per_sock_discount_cents integer, _number_of_socks_free integer)
+  returns setof sos.coupon
+  language plpgsql
+as $function$
+declare
+  _coupon_uuid uuid;
+begin
+  insert into sos."coupon" (
+    coupon_code,
+    coupon_valid_until,
+    coupon_free_shipping,
+    coupon_number_allowed_uses,
+    coupon_flat_discount_cents,
+    coupon_percent_discount,
+    coupon_per_sock_discount_cents,
+    coupon_number_of_socks_free
+  ) values (
+    _code,
+    _valid_until,
+    _free_shipping,
+    _number_allowed_uses,
+    _flat_discount_cents,
+    _percent_discount,
+    _per_sock_discount_cents,
+    _number_of_socks_free
+  ) returning coupon_uuid into _coupon_uuid;
+
+  return query select * from sos.coupon where coupon_uuid = _coupon_uuid;
+end; $function$;
+
+create or replace function sos.add_coupon_to_transaction(_transaction_uuid uuid, _coupon_uuid uuid, _item_discount integer)
+  returns setof sos.v_order
+  language plpgsql
+as $function$
+declare
+  _order_uuid uuid;
+  _purchased_transactions integer;
+begin
+    -- Get the transaction's order
+  select transaction_order_uuid into _order_uuid
+    from sos."transaction"
+    where transaction_uuid = _transaction_uuid;
+
+  if _order_uuid is null then
+    raise 'Transaction has no order';
+  end if;
+
+  -- TODO: Check for other uses of this coupon.  Compare to the number_allowed_uses.
+
+  -- Check that this transaction is "started"
+  select count(*) into _purchased_transactions
+    from sos.v_order
+    where transaction_uuid = _transaction_uuid
+      and transaction_payment_state != 'started';
+
+  if _purchased_transactions > 0 then
+    raise 'Order has been cancelled or purchased';
+  end if;
+
+  -- Update transaction
+  update sos."transaction" set (
+    transaction_coupon_uuid,
+    transaction_coupon_effective_discount
+   ) = (
+    _coupon_uuid,
+    _item_discount
+   ) where transaction_uuid = _transaction_uuid;
+
+  return query select * from sos.v_order where order_uuid = _order_uuid;
+end; $function$;

db/util.js

@@ -0,0 +1,31 @@
+const pg = require('./pg')
+const mappings = require('./mappings')
+const joinjs = require('join-js').default;
+const debug = require('debug')('sos:db')
+
+const util = module.exports = {};
+const validateFunctionName = name => /^[a-z_]+$/.test(name)
+const getParamString = (length) => Array.from({length}, (_,i)=>i+1).map(i => '$' + i).join(', ')
+
+util.executeQuery = async function({query, returnType, single = false}){
+  debug(query)
+
+  const {rows} = await pg.query(query)
+
+  const mappedObjs = joinjs.map(rows, mappings, returnType + 'Map', returnType + '_')
+
+  if(single)
+    return mappedObjs[0]
+  return mappedObjs
+}
+
+util.executeFunction = async function({name, params, returnType, single}) {
+  if(!validateFunctionName(name)) throw new Error("Invalid function name: " + name);
+
+  const query = {
+    text: `select * from sos.${name}( ${getParamString(params.length)} )`,
+    values: params
+  }
+
+  return util.executeQuery({query, returnType, single})
+}

pages/store/checkout/index.js

@@ -1,9 +1,11 @@
+import {useState, useRef} from 'react'
 import Link from 'next/link'
 import Router from 'next/router'
 import styles from './style.module.css'
 import {Icon} from '@rmwc/icon'
 import {Input, Button} from '~/components/form'
 import useUser from '~/hooks/useUser'
+import axios from 'axios'
 
 // TODO: Load previous addresses
 CheckoutSummary.getInitialProps = async function({ctx: {axios}}){
@@ -11,8 +13,9 @@ CheckoutSummary.getInitialProps = async function({ctx: {axios}}){
   return {order}
 }
 
-export default function CheckoutSummary({order}){
+export default function CheckoutSummary({order: _order}){
   const user = useUser();
+  const [order, updateOrder] = useState(_order)
 
   const currentTransaction = order
     .transactions.find(transaction => (
@@ -20,7 +23,7 @@ export default function CheckoutSummary({order}){
     ))
 
   const {item_total_price, shipping_price, tax_price, coupon_effective_discount} = currentTransaction
-  console.log(tax_price)
+  const {free_shipping} = currentTransaction.coupon || {}
 
   const formatMoney = money => {
     if (money === undefined || money === null) return null;
@@ -30,9 +33,19 @@ export default function CheckoutSummary({order}){
 
   const total_price =
       (item_total_price && shipping_price && tax_price)
-        ? item_total_price + shipping_price + tax_price - (coupon_effective_discount || 0)
+        ? item_total_price + (free_shipping ? 0 : shipping_price) + tax_price - (coupon_effective_discount || 0)
         : null
 
+  // For coupon input
+  const couponRef = useRef()
+  const onCouponSubmit = async ev => {
+    if(ev) ev.preventDefault()
+
+    const code = couponRef.current?.value
+    const {data: updatedOrder} = await axios.post(`/api/orders/current/coupon`, {code})
+    updateOrder(updatedOrder)
+  }
+
   return (
     <>
       <h2>Checkout</h2>
@@ -79,38 +92,63 @@ export default function CheckoutSummary({order}){
       </div>
       <div className={styles.checkoutSection}>
         <h3>Coupon (optional)</h3>
-        <div className={styles.horizContainer} style={{maxWidth:'400px', margin: '0 auto'}}>
-          <Input label="" name="coupon" />
-          <div style={{maxWidth: '120px', marginLeft: '8px'}}>
-            <Button outline>Save Coupon</Button>
-          </div>
-        </div>
+        {
+          currentTransaction.coupon
+            ? (
+              <>
+                <p style={{textAlign: 'center'}}>
+                  Using coupon code: <strong>{currentTransaction.coupon.code}</strong><br/>
+                  (
+                    {coupon_effective_discount > 0 && `Discounting by ${formatMoney(coupon_effective_discount)}`}
+                    {coupon_effective_discount > 0 && free_shipping && ' & '}
+                    {free_shipping && `${coupon_effective_discount > 0 ? 'f' : 'F'}ree shipping`}
+                  )
+                </p>
+              </>
+            )
+            : (
+              <div className={styles.horizContainer} style={{maxWidth:'400px', margin: '0 auto'}}>
+                <Input inputRef={couponRef} label="" name="coupon" />
+                <div style={{maxWidth: '120px', marginLeft: '8px'}}>
+                  <Button onClick={onCouponSubmit} outline>Save Coupon</Button>
+                </div>
+              </div>
+            )
+        }
       </div>
       <div className={styles.checkoutSection}>
         <h3>Total</h3>
         <div className={styles.horizContainer}>
           <div>
             <table>
-              {currentTransaction.cart.items.map(({uuid, count, item}) => (
-                <tr key={uuid}>
-                  <td>{item.name} {count > 1 ? `(${count})` : ''}:</td>
-                  <td>{formatMoney(count * item.price_cents)}</td>
+              <tbody>
+                {currentTransaction.cart.items.map(({uuid, count, item}) => (
+                  <tr key={uuid}>
+                    <td>{item.name} {count > 1 ? `(${count})` : ''}:</td>
+                    <td>{formatMoney(count * item.price_cents)}</td>
+                  </tr>
+                ))}
+                {coupon_effective_discount > 0 && (
+                  <tr>
+                    <td>Coupon:</td>
+                    <td>- {formatMoney(coupon_effective_discount)}</td>
+                  </tr>
+                )}
+                <tr className={free_shipping ? 'strikethrough' : undefined}>
+                  <td>Shipping:</td>
+                  <td>{formatMoney(shipping_price) || '-'}</td>
                 </tr>
-              ))}
-              <tr>
-                <td>Shipping:</td>
-                <td>{formatMoney(shipping_price) || '-'}</td>
-              </tr>
-              {tax_price && (
-                <tr>
-                  <td>Sales tax:</td>
-                <td>{formatMoney(tax_price)}</td>
+                {tax_price && (
+                  <tr>
+                    <td>Sales tax:</td>
+                  <td>{formatMoney(tax_price)}</td>
+                  </tr>
+                )}
+                <tr style={{fontWeight: 'bold'}}>
+                  <td>Total:</td>
+                  <td>{formatMoney(total_price) || '-'}</td>
                 </tr>
-              )}
-              <tr style={{fontWeight: 'bold'}}>
-                <td>Total:</td>
-                <td>{formatMoney(total_price) || '-'}</td>
-              </tr>
+              </tbody>
             </table>
           </div>
           <div className={styles.paymentButtons}>

styles/layout.css

@@ -95,3 +95,18 @@ button.buttonLink:focus {
     column-count: 1;
   }
 }
+
+table tr.strikethrough {
+  opacity: .6;
+  position: relative;
+}
+
+table tr.strikethrough::after {
+  content: ' ';
+  position: absolute;
+  display: block;
+  left: 0;
+  right: 0;
+  top: 50%;
+  border-top: solid 1px black;
+}