add interest

apps/admin.saladeaula.digital/app/routes/_.$orgid.enrollments.buy/payment.tsx

@@ -29,10 +29,13 @@ import {
   NativeSelect,
   NativeSelectOption
 } from '@repo/ui/components/ui/native-select'
+import { Currency } from '@repo/ui/components/currency'
 
 import { useWizard } from '@/components/wizard'
 import { isName } from '../_.$orgid.users.add/data'
 import type { PaymentMethod } from '@repo/ui/routes/orders/data'
+import type { WizardState } from './route'
+import { applyDiscount } from './discount'
 
 const creditCard = z.object({
   holder_name: z
@@ -52,31 +55,32 @@ const creditCard = z.object({
   cvv: z.string().min(3).max(4)
 })
 
-const formSchema = z.discriminatedUnion(
-  'payment_method',
-  [
-    z.object({
-      payment_method: z.literal('PIX')
-    }),
-    z.object({
-      payment_method: z.literal('BANK_SLIP')
-    }),
-    z.object({
-      payment_method: z.literal('MANUAL')
-    }),
-    z.object({
-      payment_method: z.literal('CREDIT_CARD'),
-      credit_card: creditCard
-    })
-  ],
-  { error: 'Escolha uma forma de pagamento' }
-)
+const formSchema = z.discriminatedUnion('payment_method', [
+  z.object({
+    payment_method: z.literal('PIX')
+  }),
 
-type Schema = z.infer<typeof formSchema>
+  z.object({
+    payment_method: z.literal('BANK_SLIP')
+  }),
+
+  z.object({
+    payment_method: z.literal('MANUAL')
+  }),
+
+  z.object({
+    payment_method: z.literal('CREDIT_CARD'),
+    credit_card: creditCard,
+    installments: z.coerce.number().int().min(1).max(12)
+  })
+])
+
+type Schema = z.input<typeof formSchema>
 
 export type CreditCard = z.infer<typeof creditCard>
 
 type PaymentProps = {
+  state: WizardState
   onSubmit: (value: any) => void | Promise<void>
   payment_method?: PaymentMethod
   credit_card?: CreditCard
@@ -84,6 +88,7 @@ type PaymentProps = {
 
 export function Payment({
   onSubmit,
+  state,
   payment_method: paymentMethodInit,
   credit_card: creditCardInit = undefined
 }: PaymentProps) {
@@ -91,11 +96,23 @@ export function Payment({
   const { control, handleSubmit } = useForm<Schema>({
     defaultValues: {
       payment_method: paymentMethodInit,
+      installments: state?.installments ?? 1,
       credit_card: creditCardInit
     },
     resolver: zodResolver(formSchema)
   })
   const paymentMethod = useWatch({ control, name: 'payment_method' })
+  const subtotal = state.items.reduce(
+    (acc, { course, quantity }) =>
+      acc +
+      (course?.unit_price || 0) *
+        (Number.isFinite(quantity) && quantity > 0 ? quantity : 1),
+    0
+  )
+  const discount = state.coupon
+    ? applyDiscount(subtotal, state.coupon.amount, state.coupon.type) * -1
+    : 0
+  const total = subtotal > 0 ? subtotal + discount : 0
 
   const onSubmit_ = async (data: Schema) => {
     await onSubmit({ credit_card: undefined, ...data })
@@ -147,7 +164,7 @@ export function Payment({
       />
 
       {paymentMethod === 'CREDIT_CARD' ? (
-        <CreditCard control={control} />
+        <CreditCard control={control} total={total} />
       ) : null}
 
       <Separator />
@@ -171,7 +188,13 @@ export function Payment({
   )
 }
 
-export function CreditCard({ control }: { control: Control<Schema> }) {
+export function CreditCard({
+  total,
+  control
+}: {
+  total: number
+  control: Control<Schema>
+}) {
   const currentYear = new Date().getFullYear()
   const years = Array.from({ length: 10 }, (_, i) => currentYear + i)
 
@@ -325,9 +348,58 @@ export function CreditCard({ control }: { control: Control<Schema> }) {
                 )}
               />
             </FieldSet>
+
+            <Controller
+              control={control}
+              name="installments"
+              defaultValue={1}
+              render={({ field, fieldState }) => (
+                <Field data-invalid={fieldState.invalid}>
+                  <FieldLabel htmlFor={field.name}>Parcelas</FieldLabel>
+                  <NativeSelect
+                    id={field.name}
+                    value={String(field.value)}
+                    onChange={field.onChange}
+                    aria-invalid={fieldState.invalid}
+                  >
+                    {Array.from({ length: 12 }, (_, index) => {
+                      const installment = index + 1 // 1 -> 12
+
+                      if (installment === 1) {
+                        return (
+                          <NativeSelectOption key={installment} value={1}>
+                            <Currency>{total}</Currency> à vista
+                          </NativeSelectOption>
+                        )
+                      }
+
+                      const value =
+                        calcInterest(total, installment) / installment
+
+                      return (
+                        <NativeSelectOption
+                          key={installment}
+                          value={installment}
+                        >
+                          {installment}x <Currency>{value}</Currency> com juros
+                        </NativeSelectOption>
+                      )
+                    })}
+                  </NativeSelect>
+                </Field>
+              )}
+            />
           </FieldSet>
         </FieldGroup>
       </CardContent>
     </Card>
   )
 }
+
+export const calcInterest = (total: number, installment: number) => {
+  const rate2to6 = 0.055
+  const rate7to12 = 0.0608
+  const rate = installment >= 7 ? rate7to12 : rate2to6
+
+  return total * ((1 - 0.0382) / (1 - rate))
+}