uniswap-interface-uncensored/src/hooks/useV2Pairs.ts

66 lines
2.1 KiB
TypeScript

import { Pair } from '@uniswap/v2-sdk'
import { useMemo } from 'react'
import { abi as IUniswapV2PairABI } from '@uniswap/v2-core/build/IUniswapV2Pair.json'
import { Interface } from '@ethersproject/abi'
import { useActiveWeb3React } from './web3'
import { useMultipleContractSingleData } from '../state/multicall/hooks'
import { wrappedCurrency } from '../utils/wrappedCurrency'
import { Currency, CurrencyAmount } from '@uniswap/sdk-core'
const PAIR_INTERFACE = new Interface(IUniswapV2PairABI)
export enum PairState {
LOADING,
NOT_EXISTS,
EXISTS,
INVALID,
}
export function useV2Pairs(currencies: [Currency | undefined, Currency | undefined][]): [PairState, Pair | null][] {
const { chainId } = useActiveWeb3React()
const tokens = useMemo(
() =>
currencies.map(([currencyA, currencyB]) => [
wrappedCurrency(currencyA, chainId),
wrappedCurrency(currencyB, chainId),
]),
[chainId, currencies]
)
const pairAddresses = useMemo(
() =>
tokens.map(([tokenA, tokenB]) => {
return tokenA && tokenB && !tokenA.equals(tokenB) ? Pair.getAddress(tokenA, tokenB) : undefined
}),
[tokens]
)
const results = useMultipleContractSingleData(pairAddresses, PAIR_INTERFACE, 'getReserves')
return useMemo(() => {
return results.map((result, i) => {
const { result: reserves, loading } = result
const tokenA = tokens[i][0]
const tokenB = tokens[i][1]
if (loading) return [PairState.LOADING, null]
if (!tokenA || !tokenB || tokenA.equals(tokenB)) return [PairState.INVALID, null]
if (!reserves) return [PairState.NOT_EXISTS, null]
const { reserve0, reserve1 } = reserves
const [token0, token1] = tokenA.sortsBefore(tokenB) ? [tokenA, tokenB] : [tokenB, tokenA]
return [
PairState.EXISTS,
new Pair(
CurrencyAmount.fromRawAmount(token0, reserve0.toString()),
CurrencyAmount.fromRawAmount(token1, reserve1.toString())
),
]
})
}, [results, tokens])
}
export function useV2Pair(tokenA?: Currency, tokenB?: Currency): [PairState, Pair | null] {
return useV2Pairs([[tokenA, tokenB]])[0]
}