Claim dynamic prices (#2182)

* Added dependecy on @gnosis.pm/cow-token

* Renamed vCOW abi function wethPrice to nativeTokenPrice

* Importing ClaimType from cow-token contract package

* Refactoring imports on claim/hooks

* Revert "Renamed vCOW abi function wethPrice to nativeTokenPrice"

This reverts commit c1ec593.

* New hooks for price fetching from the contract

* Using new hooks and removing hardcoded price values

* Added TODO about new price fn name

* Revert "Refactoring imports on claim/hooks"

This reverts commit 50bafab.

* Revert "Importing ClaimType from cow-token contract package"

This reverts commit b2c79f0.

* Revert "Added dependecy on @gnosis.pm/cow-token"

This reverts commit f0bbea4.

Co-authored-by: Leandro <[email protected]>

src/custom/state/claim/hooks/index.ts

@@ -4,6 +4,7 @@ import ms from 'ms.macro'
 import { CurrencyAmount, Price, Token } from '@uniswap/sdk-core'
 import { TransactionResponse } from '@ethersproject/providers'
 import { parseUnits } from '@ethersproject/units'
+import { BigNumber } from '@ethersproject/bignumber'
 
 import { VCow as VCowType } from 'abis/types'
 
@@ -63,17 +64,6 @@ const ONE_VCOW = CurrencyAmount.fromRawAmount(
   V_COW[SupportedChainId.RINKEBY],
   parseUnits('1', V_COW[SupportedChainId.RINKEBY].decimals).toString()
 )
-// TODO: these values came from the test contract, might be different on real deployment
-// Network variable price
-export const NATIVE_TOKEN_PRICE: { [chain in SupportedChainId]: string } = {
-  [SupportedChainId.MAINNET]: '37500000000000', // '0.0000375' WETH (18 decimals) per vCOW, in wei
-  [SupportedChainId.RINKEBY]: '37500000000000', // assuming Rinkeby has same price as Mainnet
-  [SupportedChainId.XDAI]: '150000000000000000', // TODO: wild guess, wxDAI is same price as USDC
-}
-
-// Same on all networks. Actually, likely available only on Mainnet (and Rinkeby)
-export const GNO_PRICE = '375000000000000' // '0.000375' GNO (18 decimals) per vCOW, in atoms
-export const USDC_PRICE = '150000' // '0.15' USDC (6 decimals) per vCOW, in atoms
 
 // Constants regarding investment time windows
 const INVESTMENT_TIME = ms`2 weeks`
@@ -339,6 +329,55 @@ export function useClaimTimeInfo(): ClaimTimeInfo {
   return { deployment, investmentDeadline, airdropDeadline, isInvestmentWindowOpen, isAirdropWindowOpen }
 }
 
+export function useNativeTokenPrice(): string | null {
+  // TODO: rename fn to `nativeTokenPrice` and revert e7197dd27287ff1460a7d7af22734cae938b8c83
+  //  when there's a new deployment
+  return _useVCowPriceForToken('wethPrice')
+}
+
+export function useGnoPrice(): string | null {
+  return _useVCowPriceForToken('gnoPrice')
+}
+
+export function useUsdcPrice(): string | null {
+  return _useVCowPriceForToken('usdcPrice')
+}
+
+/**
+ * Generic hook for fetching contract value for the many prices
+ */
+function _useVCowPriceForToken(priceFnName: 'wethPrice' | 'gnoPrice' | 'usdcPrice'): string | null {
+  const { chainId } = useActiveWeb3React()
+  const vCowContract = useVCowContract()
+
+  const [price, setPrice] = useState<string | null>(null)
+
+  useEffect(() => {
+    if (!chainId || !vCowContract) {
+      return
+    }
+    console.debug(`_useVCowPriceForToken::fetching price for `, priceFnName)
+
+    vCowContract[priceFnName]().then((price: BigNumber) => setPrice(price.toString()))
+  }, [chainId, priceFnName, vCowContract])
+
+  return price
+}
+
+export type VCowPrices = {
+  native: string | null
+  gno: string | null
+  usdc: string | null
+}
+
+export function useVCowPrices(): VCowPrices {
+  const native = useNativeTokenPrice()
+  const gno = useGnoPrice()
+  const usdc = useUsdcPrice()
+
+  return useMemo(() => ({ native, gno, usdc }), [gno, native, usdc])
+}
+
 /**
  * Helper function that checks whether selected investment options are still available
  *
@@ -378,6 +417,7 @@ export function useClaimCallback(account: string | null | undefined): {
   const { chainId, account: connectedAccount } = useActiveWeb3React()
   const claims = useUserAvailableClaims(account)
   const vCowContract = useVCowContract()
+  const nativeTokenPrice = useNativeTokenPrice()
 
   const { isInvestmentWindowOpen, isAirdropWindowOpen } = useClaimTimeInfo()
 
@@ -421,14 +461,21 @@ export function useClaimCallback(account: string | null | undefined): {
         !connectedAccount ||
         !chainId ||
         !vCowContract ||
-        !vCowToken
+        !vCowToken ||
+        !nativeTokenPrice
       ) {
         throw new Error("Not initialized, can't claim")
       }
 
       _validateClaimable(claims, claimInput, isInvestmentWindowOpen, isAirdropWindowOpen)
 
-      const { args, totalClaimedAmount } = _getClaimManyArgs({ claimInput, claims, account, connectedAccount, chainId })
+      const { args, totalClaimedAmount } = _getClaimManyArgs({
+        claimInput,
+        claims,
+        account,
+        connectedAccount,
+        nativeTokenPrice,
+      })
 
       if (!args) {
         throw new Error('There were no valid claims selected')
@@ -461,6 +508,7 @@ export function useClaimCallback(account: string | null | undefined): {
       connectedAccount,
       isAirdropWindowOpen,
       isInvestmentWindowOpen,
+      nativeTokenPrice,
       vCowContract,
       vCowToken,
     ]
@@ -474,7 +522,7 @@ type GetClaimManyArgsParams = {
   claims: UserClaims
   account: string
   connectedAccount: string
-  chainId: SupportedChainId
+  nativeTokenPrice: string
 }
 
 type ClaimManyFnArgs = Parameters<VCowType['claimMany']>
@@ -492,7 +540,7 @@ function _getClaimManyArgs({
   claims,
   account,
   connectedAccount,
-  chainId,
+  nativeTokenPrice,
 }: GetClaimManyArgsParams): GetClaimManyArgsResult {
   // Arrays are named according to contract parameters
   // For more info, check https://github.com/gnosis/gp-v2-token/blob/main/src/contracts/mixins/MerkleDistributor.sol#L123
@@ -532,7 +580,7 @@ function _getClaimManyArgs({
 
       merkleProofs.push(claim.proof)
       // only used on UserOption
-      const value = _getClaimValue(claim, claimedAmount, chainId)
+      const value = _getClaimValue(claim, claimedAmount, nativeTokenPrice)
       sendEth.push(value) // TODO: verify ETH balance < input.amount ?
 
       // sum of claimedAmounts for the toast notification
@@ -615,16 +663,14 @@ function _hasNoInputOrInputIsGreaterThanClaimAmount(
  * vCowAmount * wethPrice / 10^18
  * See https://github.com/gnosis/gp-v2-token/blob/main/src/contracts/mixins/Claiming.sol#L314-L320
  */
-function _getClaimValue(claim: UserClaimData, vCowAmount: string, chainId: SupportedChainId): string {
+function _getClaimValue(claim: UserClaimData, vCowAmount: string, nativeTokenPrice: string): string {
   if (claim.type !== ClaimType.UserOption) {
     return '0'
   }
 
-  const price = NATIVE_TOKEN_PRICE[chainId]
-
   // Why InAtomsSquared? because we are multiplying vCowAmount (which is in atoms == * 10**18)
   // by the price (which is also in atoms == * 10**18)
-  const claimValueInAtomsSquared = JSBI.multiply(JSBI.BigInt(vCowAmount), JSBI.BigInt(price))
+  const claimValueInAtomsSquared = JSBI.multiply(JSBI.BigInt(vCowAmount), JSBI.BigInt(nativeTokenPrice))
   // Then it's divided by 10**18 to return the value in the native currency atoms
   return JSBI.divide(claimValueInAtomsSquared, DENOMINATOR).toString()
 }
@@ -749,22 +795,25 @@ export function useClaimState() {
 export function useUserEnhancedClaimData(account: Account): EnhancedUserClaimData[] {
   const { available } = useClassifiedUserClaims(account)
   const { chainId: preCheckChainId } = useActiveWeb3React()
+  const native = useNativeTokenPrice()
+  const gno = useGnoPrice()
+  const usdc = useUsdcPrice()
 
   const sorted = useMemo(() => available.sort(_sortTypes), [available])
 
   return useMemo(() => {
     const chainId = supportedChainId(preCheckChainId)
-    if (!chainId) return []
+    if (!chainId || !native || !gno || !usdc) return []
 
-    return sorted.map((claim) => _enhanceClaimData(claim, chainId))
-  }, [preCheckChainId, sorted])
+    return sorted.map((claim) => _enhanceClaimData(claim, chainId, { native, gno, usdc }))
+  }, [gno, native, preCheckChainId, sorted, usdc])
 }
 
 function _sortTypes(a: UserClaimData, b: UserClaimData): number {
   return Number(isFreeClaim(b.type)) - Number(isFreeClaim(a.type))
 }
 
-function _enhanceClaimData(claim: UserClaimData, chainId: SupportedChainId): EnhancedUserClaimData {
+function _enhanceClaimData(claim: UserClaimData, chainId: SupportedChainId, prices: VCowPrices): EnhancedUserClaimData {
   const claimAmount = CurrencyAmount.fromRawAmount(ONE_VCOW.currency, claim.amount)
 
   const data: EnhancedUserClaimData = {
@@ -773,11 +822,11 @@ function _enhanceClaimData(claim: UserClaimData, chainId: SupportedChainId): Enh
     claimAmount,
   }
 
-  const tokenAndAmount = claimTypeToTokenAmount(claim.type, chainId)
+  const tokenAndAmount = claimTypeToTokenAmount(claim.type, chainId, prices)
 
   // Free claims will have tokenAndAmount === undefined
   // If it's not a free claim, store the price and calculate cost in investment token
-  if (tokenAndAmount) {
+  if (tokenAndAmount?.amount) {
     data.price = _getPrice(tokenAndAmount)
     // get the currency amount using the price base currency (remember price was inverted)
     data.currencyAmount = CurrencyAmount.fromRawAmount(data.price.baseCurrency, claim.amount)

src/custom/state/claim/hooks/utils.ts

@@ -8,13 +8,11 @@ import {
   ClaimType,
   ClaimTypePriceMap,
   FREE_CLAIM_TYPES,
-  GNO_PRICE,
-  NATIVE_TOKEN_PRICE,
   PAID_CLAIM_TYPES,
   RepoClaims,
   TypeToPriceMapper,
-  USDC_PRICE,
   UserClaims,
+  VCowPrices,
 } from 'state/claim/hooks/index'
 
 /**
@@ -164,14 +162,14 @@ export type PaidClaimTypeToPriceMap = {
 /**
  * Helper function to get vCow price based on claim type and chainId
  */
-export function claimTypeToTokenAmount(type: ClaimType, chainId: SupportedChainId) {
+export function claimTypeToTokenAmount(type: ClaimType, chainId: SupportedChainId, prices: VCowPrices) {
   switch (type) {
     case ClaimType.GnoOption:
-      return { token: GNO[chainId], amount: GNO_PRICE }
+      return { token: GNO[chainId], amount: prices.gno as string }
     case ClaimType.Investor:
-      return { token: USDC_BY_CHAIN[chainId], amount: USDC_PRICE }
+      return { token: USDC_BY_CHAIN[chainId], amount: prices.usdc as string }
     case ClaimType.UserOption:
-      return { token: GpEther.onChain(chainId), amount: NATIVE_TOKEN_PRICE[chainId] }
+      return { token: GpEther.onChain(chainId), amount: prices.native as string }
     default:
       return undefined
   }