ed5f69db7a
* Split BuyAmountInput out of AmountInput * Buy and sell tabs. Compute some sell info * In progress * BuyPanel & SellPanel with banner above that shows current shares and toggle button * Remove "Remaining balance" * Bring back 'Place a trade'. Tweaks * Sell shares cloud function. * Sell all shares by default. Switch back to buy if sell all your shares. * Cache your shares in local storage so sell banner doesn't flicker. * Compute sale value of shares with binary search to keep k constant. * Update bets table to show BUY or SELL * Fixes from Stephen's review * Don't allow selling more than max shares in cloud function * Use modal for sell shares on desktop. * Handle floating point precision in max shares you can sell.
92 lines
2.9 KiB
TypeScript
92 lines
2.9 KiB
TypeScript
import * as admin from 'firebase-admin'
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import * as functions from 'firebase-functions'
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import { Contract } from '../../common/contract'
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import { User } from '../../common/user'
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import { Bet } from '../../common/bet'
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import { getSellBetInfo } from '../../common/sell-bet'
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import { addObjects, removeUndefinedProps } from '../../common/util/object'
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import { Fees } from '../../common/fees'
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export const sellBet = functions.runWith({ minInstances: 1 }).https.onCall(
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async (
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data: {
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contractId: string
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betId: string
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},
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context
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) => {
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const userId = context?.auth?.uid
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if (!userId) return { status: 'error', message: 'Not authorized' }
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const { contractId, betId } = data
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// run as transaction to prevent race conditions
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return await firestore.runTransaction(async (transaction) => {
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const userDoc = firestore.doc(`users/${userId}`)
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const userSnap = await transaction.get(userDoc)
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if (!userSnap.exists)
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return { status: 'error', message: 'User not found' }
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const user = userSnap.data() as User
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const contractDoc = firestore.doc(`contracts/${contractId}`)
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const contractSnap = await transaction.get(contractDoc)
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if (!contractSnap.exists)
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return { status: 'error', message: 'Invalid contract' }
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const contract = contractSnap.data() as Contract
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const { closeTime, mechanism, collectedFees, volume } = contract
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if (mechanism !== 'dpm-2')
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return {
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status: 'error',
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message: 'Sell shares only works with mechanism dpm-2',
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}
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if (closeTime && Date.now() > closeTime)
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return { status: 'error', message: 'Trading is closed' }
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const betDoc = firestore.doc(`contracts/${contractId}/bets/${betId}`)
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const betSnap = await transaction.get(betDoc)
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if (!betSnap.exists) return { status: 'error', message: 'Invalid bet' }
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const bet = betSnap.data() as Bet
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if (bet.isSold) return { status: 'error', message: 'Bet already sold' }
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const newBetDoc = firestore
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.collection(`contracts/${contractId}/bets`)
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.doc()
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const {
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newBet,
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newPool,
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newTotalShares,
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newTotalBets,
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newBalance,
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fees,
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} = getSellBetInfo(user, bet, contract, newBetDoc.id)
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if (!isFinite(newBalance)) {
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throw new Error('Invalid user balance for ' + user.username)
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}
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transaction.update(userDoc, { balance: newBalance })
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transaction.update(betDoc, { isSold: true })
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transaction.create(newBetDoc, newBet)
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transaction.update(
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contractDoc,
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removeUndefinedProps({
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pool: newPool,
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totalShares: newTotalShares,
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totalBets: newTotalBets,
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collectedFees: addObjects<Fees>(fees ?? {}, collectedFees ?? {}),
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volume: volume + Math.abs(newBet.amount),
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})
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)
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return { status: 'success' }
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})
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}
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)
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const firestore = admin.firestore()
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