import { Router } from 'express'
import { ensureError } from '@speckle/shared'
import { Stripe } from 'stripe'
import { getStripeEndpointSigningKey } from '@/modules/shared/helpers/envHelper'
import { db } from '@/db/knex'
import { completeCheckoutSessionFactory } from '@/modules/gatekeeper/services/checkout'
import {
  getSubscriptionDataFactory,
  parseSubscriptionData
} from '@/modules/gatekeeper/clients/stripe'
import {
  deleteCheckoutSessionFactory,
  getCheckoutSessionFactory,
  getWorkspacePlanFactory,
  upsertWorkspaceSubscriptionFactory,
  updateCheckoutSessionStatusFactory,
  upsertPaidWorkspacePlanFactory,
  getWorkspaceSubscriptionBySubscriptionIdFactory
} from '@/modules/gatekeeper/repositories/billing'
import { WorkspaceAlreadyPaidError } from '@/modules/gatekeeper/errors/billing'
import { withTransaction } from '@/modules/shared/helpers/dbHelper'
import { getStripeClient } from '@/modules/gatekeeper/stripe'
import { handleSubscriptionUpdateFactory } from '@/modules/gatekeeper/services/subscriptions'
import { getEventBus } from '@/modules/shared/services/eventBus'

export const getBillingRouter = (): Router => {
  const router = Router()

  router.post('/api/v1/billing/webhooks', async (req, res) => {
    const endpointSecret = getStripeEndpointSigningKey()
    const sig = req.headers['stripe-signature']
    if (!sig) {
      res.status(400).send('Missing payload signature')
      return
    }

    const stripe = getStripeClient()
    let event: Stripe.Event

    try {
      event = stripe.webhooks.constructEvent(
        // yes, the express json middleware auto parses the payload and stri need it in a string
        req.body,
        sig,
        endpointSecret
      )
    } catch (err) {
      res.status(400).send(`Webhook Error: ${ensureError(err).message}`)
      return
    }

    switch (event.type) {
      case 'checkout.session.async_payment_failed':
        // if payment fails, we delete the failed session
        await deleteCheckoutSessionFactory({ db })({
          checkoutSessionId: event.data.object.id
        })
        break
      case 'checkout.session.async_payment_succeeded':
      case 'checkout.session.completed':
        const session = event.data.object

        if (!session.subscription)
          return res.status(400).send('We only support subscription type checkouts')

        switch (session.payment_status) {
          case 'no_payment_required':
            // we do not need to support this status
            break
          case 'paid':
            // If the workspace is already on a paid plan, we made a bo bo.
            // existing subs should be updated via the api, not pushed through the checkout sess again
            // the start checkout endpoint should guard this!
            // get checkout session from the DB, if not found CONTACT SUPPORT!!!
            // if the session is already paid, means, we've already settled this checkout, and this is a webhook recall
            // set checkout state to paid
            // go ahead and provision the plan
            // store customer id and subscription Id associated to the workspace plan

            const subscriptionId =
              typeof session.subscription === 'string'
                ? session.subscription
                : session.subscription.id

            // this must use a transaction

            const trx = await db.transaction()

            const completeCheckout = completeCheckoutSessionFactory({
              getCheckoutSession: getCheckoutSessionFactory({ db: trx }),
              updateCheckoutSessionStatus: updateCheckoutSessionStatusFactory({
                db: trx
              }),
              upsertPaidWorkspacePlan: upsertPaidWorkspacePlanFactory({ db: trx }),
              upsertWorkspaceSubscription: upsertWorkspaceSubscriptionFactory({
                db: trx
              }),
              getSubscriptionData: getSubscriptionDataFactory({
                stripe
              }),
              emitEvent: getEventBus().emit
            })

            try {
              await withTransaction(
                completeCheckout({
                  sessionId: session.id,
                  subscriptionId
                }),
                trx
              )
            } catch (err) {
              if (err instanceof WorkspaceAlreadyPaidError) {
                // ignore the request, this is prob a replay from stripe
              } else {
                throw err
              }
            }

            break
          case 'unpaid':
            // if payment fails, we delete the failed session
            await deleteCheckoutSessionFactory({ db })({
              checkoutSessionId: event.data.object.id
            })
        }
        break

      case 'checkout.session.expired':
        // delete the checkout session from the DB
        await deleteCheckoutSessionFactory({ db })({
          checkoutSessionId: event.data.object.id
        })
        break

      case 'customer.subscription.updated':
      case 'customer.subscription.deleted':
        await handleSubscriptionUpdateFactory({
          getWorkspacePlan: getWorkspacePlanFactory({ db }),
          upsertPaidWorkspacePlan: upsertPaidWorkspacePlanFactory({ db }),
          getWorkspaceSubscriptionBySubscriptionId:
            getWorkspaceSubscriptionBySubscriptionIdFactory({ db }),
          upsertWorkspaceSubscription: upsertWorkspaceSubscriptionFactory({ db })
        })({ subscriptionData: parseSubscriptionData(event.data.object) })

        break

      default:
        break
    }

    res.status(200).send('ok')
  })

  return router
}