import { Plan, PrismaClient, WorkspaceRole } from '@typebot.io/prisma'
import { isDefined, isEmpty } from '@typebot.io/lib'
import { getChatsLimit } from '@typebot.io/billing/helpers/getChatsLimit'
import { promptAndSetEnvironment } from './utils'
import { Workspace } from '@typebot.io/schemas'
import { sendAlmostReachedChatsLimitEmail } from '@typebot.io/emails/src/emails/AlmostReachedChatsLimitEmail'
import { TelemetryEvent } from '@typebot.io/schemas/features/telemetry'
import { trackEvents } from '@typebot.io/telemetry/trackEvents'
import Stripe from 'stripe'
import { createId } from '@paralleldrive/cuid2'

const prisma = new PrismaClient()
const LIMIT_EMAIL_TRIGGER_PERCENT = 0.75

export const checkAndReportChatsUsage = async () => {
  await promptAndSetEnvironment('production')

  console.log('Get collected results from the last hour...')

  const zeroedMinutesHour = new Date()
  zeroedMinutesHour.setUTCMinutes(0, 0, 0)
  const hourAgo = new Date(zeroedMinutesHour.getTime() - 1000 * 60 * 60)

  const results = await prisma.result.groupBy({
    by: ['typebotId'],
    _count: {
      _all: true,
    },
    where: {
      hasStarted: true,
      createdAt: {
        lt: zeroedMinutesHour,
        gte: hourAgo,
      },
    },
  })

  console.log(
    `Found ${results.reduce(
      (total, result) => total + result._count._all,
      0
    )} results collected for the last hour.`
  )

  const workspaces = await prisma.workspace.findMany({
    where: {
      typebots: {
        some: {
          id: { in: results.map((result) => result.typebotId) },
        },
      },
    },
    select: {
      id: true,
      name: true,
      typebots: { select: { id: true } },
      members: {
        select: { user: { select: { id: true, email: true } }, role: true },
      },
      additionalStorageIndex: true,
      customChatsLimit: true,
      customStorageLimit: true,
      plan: true,
      isQuarantined: true,
      chatsLimitFirstEmailSentAt: true,
      chatsLimitSecondEmailSentAt: true,
      stripeId: true,
    },
  })

  if (isEmpty(process.env.STRIPE_SECRET_KEY))
    throw new Error('Missing STRIPE_SECRET_KEY env variable')

  const stripe = new Stripe(process.env.STRIPE_SECRET_KEY, {
    apiVersion: '2022-11-15',
  })

  const quarantineEvents: TelemetryEvent[] = []
  const autoUpgradeEvents: TelemetryEvent[] = []

  for (const workspace of workspaces) {
    if (workspace.isQuarantined) continue
    const chatsLimit = getChatsLimit(workspace)
    const subscription = await getSubscription(workspace, { stripe })
    const { totalChatsUsed } = await getUsage(prisma)({
      workspaceId: workspace.id,
      subscription,
    })
    if (chatsLimit === 'inf') continue
    if (
      chatsLimit > 0 &&
      totalChatsUsed >= chatsLimit * LIMIT_EMAIL_TRIGGER_PERCENT &&
      totalChatsUsed < chatsLimit &&
      !workspace.chatsLimitFirstEmailSentAt
    ) {
      const to = workspace.members
        .filter((member) => member.role === WorkspaceRole.ADMIN)
        .map((member) => member.user.email)
        .filter(isDefined)
      console.log(
        `Send almost reached chats limit email to ${to.join(', ')}...`
      )
      try {
        await sendAlmostReachedChatsLimitEmail({
          to,
          usagePercent: Math.round((totalChatsUsed / chatsLimit) * 100),
          chatsLimit,
          workspaceName: workspace.name,
        })
        await prisma.workspace.updateMany({
          where: { id: workspace.id },
          data: { chatsLimitFirstEmailSentAt: new Date() },
        })
      } catch (err) {
        console.error(err)
      }
    }

    const isUsageBasedSubscription = isDefined(
      subscription?.items.data.find(
        (item) =>
          item.price.id === process.env.STRIPE_STARTER_PRICE_ID ||
          item.price.id === process.env.STRIPE_PRO_PRICE_ID
      )
    )

    if (
      isUsageBasedSubscription &&
      subscription &&
      (workspace.plan === 'STARTER' || workspace.plan === 'PRO')
    ) {
      if (workspace.plan === 'STARTER' && totalChatsUsed >= 4000) {
        console.log(
          'Workspace has more than 4000 chats, automatically upgrading to PRO plan'
        )
        const newSubscription = await autoUpgradeToPro(subscription, {
          stripe,
          workspaceId: workspace.id,
        })
        autoUpgradeEvents.push(
          ...workspace.members
            .filter((member) => member.role === WorkspaceRole.ADMIN)
            .map(
              (member) =>
                ({
                  name: 'Subscription automatically updated',
                  userId: member.user.id,
                  workspaceId: workspace.id,
                  data: {
                    plan: 'PRO',
                  },
                } satisfies TelemetryEvent)
            )
        )
        await reportUsageToStripe(totalChatsUsed, {
          stripe,
          subscription: newSubscription,
        })
      } else {
        await reportUsageToStripe(totalChatsUsed, { stripe, subscription })
      }
    }

    if (totalChatsUsed > chatsLimit * 1.5 && workspace.plan === Plan.FREE) {
      console.log(`Automatically quarantine workspace ${workspace.id}...`)
      await prisma.workspace.updateMany({
        where: { id: workspace.id },
        data: { isQuarantined: true },
      })
      quarantineEvents.push(
        ...workspace.members
          .filter((member) => member.role === WorkspaceRole.ADMIN)
          .map(
            (member) =>
              ({
                name: 'Workspace automatically quarantined',
                userId: member.user.id,
                workspaceId: workspace.id,
                data: {
                  totalChatsUsed,
                  chatsLimit,
                },
              } satisfies TelemetryEvent)
          )
      )
    }
  }

  const resultsWithWorkspaces = results
    .flatMap((result) => {
      const workspace = workspaces.find((workspace) =>
        workspace.typebots.some((typebot) => typebot.id === result.typebotId)
      )
      if (!workspace) return
      return workspace.members
        .filter((member) => member.role !== WorkspaceRole.GUEST)
        .map((member, memberIndex) => ({
          userId: member.user.id,
          workspace: workspace,
          typebotId: result.typebotId,
          totalResultsLastHour: result._count._all,
          isFirstOfKind: memberIndex === 0 ? (true as const) : undefined,
        }))
    })
    .filter(isDefined)

  const newResultsCollectedEvents = resultsWithWorkspaces.map(
    (result) =>
      ({
        name: 'New results collected',
        userId: result.userId,
        workspaceId: result.workspace.id,
        typebotId: result.typebotId,
        data: {
          total: result.totalResultsLastHour,
          isFirstOfKind: result.isFirstOfKind,
        },
      } satisfies TelemetryEvent)
  )

  console.log(
    `Send ${newResultsCollectedEvents.length} new results events and ${quarantineEvents.length} auto quarantine events...`
  )

  await trackEvents(quarantineEvents.concat(newResultsCollectedEvents))
}

const getSubscription = async (
  workspace: Pick<Workspace, 'stripeId' | 'plan'>,
  { stripe }: { stripe: Stripe }
) => {
  if (
    !workspace.stripeId ||
    (workspace.plan !== 'STARTER' && workspace.plan !== 'PRO')
  )
    return
  const subscriptions = await stripe.subscriptions.list({
    customer: workspace.stripeId,
  })

  const currentSubscription = subscriptions.data
    .filter((sub) => ['past_due', 'active'].includes(sub.status))
    .sort((a, b) => a.created - b.created)
    .shift()

  return currentSubscription
}

const reportUsageToStripe = async (
  totalResultsLastHour: number,
  {
    stripe,
    subscription,
  }: { stripe: Stripe; subscription: Stripe.Subscription }
) => {
  if (
    !process.env.STRIPE_STARTER_CHATS_PRICE_ID ||
    !process.env.STRIPE_PRO_CHATS_PRICE_ID
  )
    throw new Error(
      'Missing STRIPE_STARTER_CHATS_PRICE_ID or STRIPE_PRO_CHATS_PRICE_ID env variable'
    )
  const subscriptionItem = subscription.items.data.find(
    (item) =>
      item.price.id === process.env.STRIPE_STARTER_CHATS_PRICE_ID ||
      item.price.id === process.env.STRIPE_PRO_CHATS_PRICE_ID
  )

  if (!subscriptionItem)
    throw new Error(`Could not find subscription item for workspace`)

  const idempotencyKey = createId()

  return stripe.subscriptionItems.createUsageRecord(
    subscriptionItem.id,
    {
      quantity: totalResultsLastHour,
      timestamp: 'now',
    },
    {
      idempotencyKey,
    }
  )
}

const getUsage =
  (prisma: PrismaClient) =>
  async ({
    workspaceId,
    subscription,
  }: {
    workspaceId: string
    subscription: Stripe.Subscription | undefined
  }) => {
    const typebots = await prisma.typebot.findMany({
      where: {
        workspaceId,
      },
      select: {
        id: true,
      },
    })

    const now = new Date()
    const firstDayOfMonth = new Date(now.getFullYear(), now.getMonth(), 1)

    const totalChatsUsed = await prisma.result.count({
      where: {
        typebotId: { in: typebots.map((typebot) => typebot.id) },
        hasStarted: true,
        createdAt: {
          gte: subscription
            ? new Date(subscription.current_period_start * 1000)
            : firstDayOfMonth,
        },
      },
    })

    return {
      totalChatsUsed,
    }
  }

const autoUpgradeToPro = async (
  subscription: Stripe.Subscription,
  { stripe, workspaceId }: { stripe: Stripe; workspaceId: string }
) => {
  if (
    !process.env.STRIPE_STARTER_CHATS_PRICE_ID ||
    !process.env.STRIPE_PRO_CHATS_PRICE_ID ||
    !process.env.STRIPE_PRO_PRICE_ID ||
    !process.env.STRIPE_STARTER_PRICE_ID
  )
    throw new Error(
      'Missing STRIPE_STARTER_CHATS_PRICE_ID or STRIPE_PRO_CHATS_PRICE_ID env variable'
    )
  const currentPlanItemId = subscription?.items.data.find((item) =>
    [
      process.env.STRIPE_PRO_PRICE_ID,
      process.env.STRIPE_STARTER_PRICE_ID,
    ].includes(item.price.id)
  )?.id

  if (!currentPlanItemId)
    throw new Error(`Could not find current plan item ID for workspace`)

  const newSubscription = stripe.subscriptions.update(subscription.id, {
    items: [
      {
        id: currentPlanItemId,
        price: process.env.STRIPE_PRO_PRICE_ID,
        quantity: 1,
      },
      {
        id: subscription.items.data.find(
          (item) =>
            item.price.id === process.env.STRIPE_STARTER_CHATS_PRICE_ID ||
            item.price.id === process.env.STRIPE_PRO_CHATS_PRICE_ID
        )?.id,
        price: process.env.STRIPE_PRO_CHATS_PRICE_ID,
      },
    ],
    proration_behavior: 'always_invoice',
  })

  await prisma.workspace.update({
    where: { id: workspaceId },
    data: {
      plan: 'PRO',
    },
  })

  return newSubscription
}

checkAndReportChatsUsage().then()