stripe-checkout.ts

import Stripe, {
  CheckoutSessionCreateParams,
} from "https://esm.sh/[email protected]?target=deno"

import {
  IS_PRODUCTION,
  STRIPE_LOCAL_SECRET_KEY,
  STRIPE_LIVE_SECRET_KEY,
} from "../_shared/constants.ts"
import { StripeAction } from "../_shared/enums.ts"
import {
  handleOptionsRequest,
  handleSuccessResponse,
} from "../_shared/responses.ts"

const getTrialEndTimestamp = () => {
  const now = Date.now()

  const oneWeekInMs = 7 * 24 * 60 * 60 * 1001
  const oneWeekFromNow = now + oneWeekInMs
  const stripeTimestamp = Math.ceil(oneWeekFromNow / 1000)

  return stripeTimestamp
}

Deno.serve(async (req) => {
  if (req.method === "OPTIONS") {
    return handleOptionsRequest(req)
  }

  const {
    stripeSubscriptionPriceId,
    userId,
    action,
    customer,
    successUrl,
    cancelUrl,
  } = await req.json()

  const stripeSk = IS_PRODUCTION
    ? STRIPE_LIVE_SECRET_KEY
    : STRIPE_LOCAL_SECRET_KEY

  const stripe = new Stripe(stripeSk, {
    apiVersion: "2022-11-15",
    httpClient: Stripe.createFetchHttpClient(),
  })

  const mode =
    action === StripeAction.BuyExtraCredits ? "payment" : "subscription"

  let sessionCreateObject: CheckoutSessionCreateParams = {
    payment_method_types: ["card"],
    line_items: [
      {
        price: stripeSubscriptionPriceId,
        quantity: 1,
      },
    ],
    automatic_tax: {
      enabled: true,
    },
    mode,
    tax_id_collection: {
      enabled: true,
    },
    allow_promotion_codes: true,
    success_url: successUrl,
    cancel_url: cancelUrl,
    metadata: {
      userId,
      stripeSubscriptionPriceId,
      action,
    },
  }

  if (action === StripeAction.TryForFree) {
    sessionCreateObject = {
      ...sessionCreateObject,
      subscription_data: {
        trial_end: getTrialEndTimestamp(),
      },
    }
  }

  if (mode === "payment") {
    sessionCreateObject = {
      ...sessionCreateObject,
      invoice_creation: {
        enabled: true,
      },
    }
  }

  if (customer) {
    sessionCreateObject = {
      ...sessionCreateObject,
      customer,
      customer_update: {
        name: "auto",
        address: "auto",
      },
    }
  }

  const session = await stripe.checkout.sessions.create(sessionCreateObject)

  const data = {
    id: session.id,
  }

  return handleSuccessResponse("stripe-checkout", data)
})