import * as functions from 'firebase-functions'
import * as admin from 'firebase-admin'
import { difference, uniq, mapValues, groupBy, sumBy } from 'lodash'

import { Contract, resolution, RESOLUTIONS } from '../../common/contract'
import { User } from '../../common/user'
import { Bet } from '../../common/bet'
import { getUser, isProd, payUser } from './utils'
import { sendMarketResolutionEmail } from './emails'
import {
  getLoanPayouts,
  getPayouts,
  groupPayoutsByUser,
  Payout,
} from '../../common/payouts'
import { removeUndefinedProps } from '../../common/util/object'
import { LiquidityProvision } from '../../common/liquidity-provision'

export const resolveMarket = functions
  .runWith({ minInstances: 1, secrets: ['MAILGUN_KEY'] })
  .https.onCall(
    async (
      data: {
        outcome: resolution
        value?: number
        contractId: string
        probabilityInt?: number
        resolutions?: { [outcome: string]: number }
      },
      context
    ) => {
      const userId = context?.auth?.uid
      if (!userId) return { status: 'error', message: 'Not authorized' }

      const { outcome, contractId, probabilityInt, resolutions, value } = data

      const contractDoc = firestore.doc(`contracts/${contractId}`)
      const contractSnap = await contractDoc.get()
      if (!contractSnap.exists)
        return { status: 'error', message: 'Invalid contract' }
      const contract = contractSnap.data() as Contract
      const { creatorId, outcomeType, closeTime } = contract

      if (outcomeType === 'BINARY') {
        if (!RESOLUTIONS.includes(outcome))
          return { status: 'error', message: 'Invalid outcome' }
      } else if (outcomeType === 'FREE_RESPONSE') {
        if (
          isNaN(+outcome) &&
          !(outcome === 'MKT' && resolutions) &&
          outcome !== 'CANCEL'
        )
          return { status: 'error', message: 'Invalid outcome' }
      } else if (outcomeType === 'NUMERIC') {
        if (isNaN(+outcome) && outcome !== 'CANCEL')
          return { status: 'error', message: 'Invalid outcome' }
      } else {
        return { status: 'error', message: 'Invalid contract outcomeType' }
      }

      if (value !== undefined && !isFinite(value))
        return { status: 'error', message: 'Invalid value' }

      if (
        outcomeType === 'BINARY' &&
        probabilityInt !== undefined &&
        (probabilityInt < 0 ||
          probabilityInt > 100 ||
          !isFinite(probabilityInt))
      )
        return { status: 'error', message: 'Invalid probability' }

      if (creatorId !== userId)
        return { status: 'error', message: 'User not creator of contract' }

      if (contract.resolution)
        return { status: 'error', message: 'Contract already resolved' }

      const creator = await getUser(creatorId)
      if (!creator) return { status: 'error', message: 'Creator not found' }

      const resolutionProbability =
        probabilityInt !== undefined ? probabilityInt / 100 : undefined

      const resolutionTime = Date.now()
      const newCloseTime = closeTime
        ? Math.min(closeTime, resolutionTime)
        : closeTime

      const betsSnap = await firestore
        .collection(`contracts/${contractId}/bets`)
        .get()

      const bets = betsSnap.docs.map((doc) => doc.data() as Bet)

      const liquiditiesSnap = await firestore
        .collection(`contracts/${contractId}/liquidity`)
        .get()

      const liquidities = liquiditiesSnap.docs.map(
        (doc) => doc.data() as LiquidityProvision
      )

      const { payouts, creatorPayout, liquidityPayouts, collectedFees } =
        getPayouts(
          outcome,
          resolutions ?? {},
          contract,
          bets,
          liquidities,
          resolutionProbability
        )

      await contractDoc.update(
        removeUndefinedProps({
          isResolved: true,
          resolution: outcome,
          resolutionValue: value,
          resolutionTime,
          closeTime: newCloseTime,
          resolutionProbability,
          resolutions,
          collectedFees,
        })
      )

      console.log('contract ', contractId, 'resolved to:', outcome)

      const openBets = bets.filter((b) => !b.isSold && !b.sale)
      const loanPayouts = getLoanPayouts(openBets)

      if (!isProd)
        console.log(
          'payouts:',
          payouts,
          'creator payout:',
          creatorPayout,
          'liquidity payout:'
        )

      if (creatorPayout)
        await processPayouts(
          [{ userId: creatorId, payout: creatorPayout }],
          true
        )

      await processPayouts(liquidityPayouts, true)

      const result = await processPayouts([...payouts, ...loanPayouts])

      const userPayoutsWithoutLoans = groupPayoutsByUser(payouts)

      await sendResolutionEmails(
        openBets,
        userPayoutsWithoutLoans,
        creator,
        creatorPayout,
        contract,
        outcome,
        resolutionProbability,
        resolutions
      )

      return result
    }
  )

const processPayouts = async (payouts: Payout[], isDeposit = false) => {
  const userPayouts = groupPayoutsByUser(payouts)

  const payoutPromises = Object.entries(userPayouts).map(([userId, payout]) =>
    payUser(userId, payout, isDeposit)
  )

  return await Promise.all(payoutPromises)
    .catch((e) => ({ status: 'error', message: e }))
    .then(() => ({ status: 'success' }))
}

const sendResolutionEmails = async (
  openBets: Bet[],
  userPayouts: { [userId: string]: number },
  creator: User,
  creatorPayout: number,
  contract: Contract,
  outcome: string,
  resolutionProbability?: number,
  resolutions?: { [outcome: string]: number }
) => {
  const nonWinners = difference(
    uniq(openBets.map(({ userId }) => userId)),
    Object.keys(userPayouts)
  )
  const investedByUser = mapValues(
    groupBy(openBets, (bet) => bet.userId),
    (bets) => sumBy(bets, (bet) => bet.amount)
  )
  const emailPayouts = [
    ...Object.entries(userPayouts),
    ...nonWinners.map((userId) => [userId, 0] as const),
  ].map(([userId, payout]) => ({
    userId,
    investment: investedByUser[userId] ?? 0,
    payout,
  }))

  await Promise.all(
    emailPayouts.map(({ userId, investment, payout }) =>
      sendMarketResolutionEmail(
        userId,
        investment,
        payout,
        creator,
        creatorPayout,
        contract,
        outcome,
        resolutionProbability,
        resolutions
      )
    )
  )
}

const firestore = admin.firestore()