Add @thesis-co/cent, refactor currency conversion

Removes "convertUSDAmountToCurrency" in favor of converting asset price
points into the user currency before formatting. cent is mostly
providing currency metadata for now.

Author: hyphenized

background/assets.ts

@@ -1,5 +1,6 @@
 import { keyBy } from "lodash"
 import { TokenList } from "@uniswap/token-lists"
+import { FixedPoint } from "@thesis-co/cent/dist/types"
 import { UNIXTime, HexString } from "./types"
 import {
   NetworkSpecific,
@@ -100,16 +101,15 @@ export type FungibleAsset = Asset & {
  * to any `FungibleAsset` and vice versa.
  */
 
-export type FiatCurrency = FungibleAsset & {
-  sign: string
-}
+export type FiatCurrency = FungibleAsset
 
 // Used for displaying balances and values in the user selected currency
-export type DisplayCurrency = FiatCurrency & {
+export type DisplayCurrency = {
+  code: string
   /**
    * Conversion rate for 1 usd
    */
-  rate: bigint
+  rate: FixedPoint
 }
 
 /**

background/constants/currencies.ts

@@ -1,16 +1,8 @@
-import { CoinGeckoAsset, DisplayCurrency } from "../assets"
+import { CoinGeckoAsset, FiatCurrency } from "../assets"
 import { NetworkBaseAsset } from "../networks"
 import { BASE_ASSETS_BY_CUSTOM_NAME } from "./base-assets"
 import { coinTypesByAssetSymbol } from "./coin-types"
 
-export const USD: DisplayCurrency = {
-  name: "United States Dollar",
-  symbol: "USD",
-  decimals: 10,
-  rate: 1_000_000_0000n, // 1 USD = 1 USD
-  sign: "$",
-}
-
 /**
  * The default currency used for pricing assets in fiat money.
  *
@@ -21,7 +13,11 @@ export const USD: DisplayCurrency = {
  * - A price oracle using the asset USDC pair.
  * - CoinGecko query using USD (currently disabled due to new limits).
  */
-export const DEFAULT_DISPLAY_CURRENCY = USD
+export const USD: FiatCurrency = {
+  name: "United States Dollar",
+  symbol: "USD",
+  decimals: 10,
+}
 
 export const ETH_DATA = {
   coinType: coinTypesByAssetSymbol.ETH,

background/package.json

@@ -42,6 +42,7 @@
     "@tallyho/hd-keyring": "0.5.0",
     "@tallyho/provider-bridge-shared": "0.0.1",
     "@tallyho/window-provider": "0.0.1",
+    "@thesis-co/cent": "0.0.4",
     "@testing-library/dom": "^9.3.1",
     "@types/w3c-web-usb": "^1.0.5",
     "@uniswap/token-lists": "^1.0.0-beta.30",

background/redux-slices/prices.ts

@@ -7,7 +7,7 @@ import {
   PricePoint,
   SmartContractFungibleAsset,
 } from "../assets"
-import { DEFAULT_DISPLAY_CURRENCY } from "../constants"
+import { USD } from "../constants"
 import { convertFixedPoint } from "../lib/fixed-point"
 import {
   FullAssetID,
@@ -40,7 +40,7 @@ const pricesSlice = createSlice({
       pricePoints.forEach((pricePoint) => {
         const fiatCurrency = pricePoint.pair.find(
           // FIXME: What if we have price points not in USD?
-          (asset) => asset.symbol === DEFAULT_DISPLAY_CURRENCY.symbol,
+          (asset) => asset.symbol === USD.symbol,
         )
 
         const [pricedAsset] = pricePoint.pair.filter(

background/redux-slices/selectors/accountsSelectors.ts

@@ -8,7 +8,7 @@ import {
 } from "../accounts"
 import { AssetsState } from "../assets"
 import {
-  convertUSDAmountToCurrency,
+  convertUSDPricePointToCurrency,
   enrichAssetAmountWithDecimalValues,
   enrichAssetAmountWithMainCurrencyValues,
   formatCurrencyAmount,
@@ -273,7 +273,7 @@ export const selectAccountAndTimestampedActivities = createSelector(
         assets: combinedAssetAmounts,
         totalMainCurrencyValue: isDefined(totalMainCurrencyAmount)
           ? formatCurrencyAmount(
-              displayCurrency.symbol,
+              displayCurrency.code,
               totalMainCurrencyAmount,
               desiredDecimals.default,
             )
@@ -326,7 +326,7 @@ export const selectCurrentAccountBalances = createSelector(
       unverifiedAssetAmounts,
       totalMainCurrencyValue: isDefined(totalMainCurrencyAmount)
         ? formatCurrencyAmount(
-            displayCurrency.symbol,
+            displayCurrency.code,
             totalMainCurrencyAmount,
             desiredDecimals.default,
           )
@@ -411,28 +411,18 @@ const getTotalBalance = (
         return 0
       }
 
-      const usdAmount = convertAssetAmountViaPricePoint(
-        assetAmount,
+      const pricePoint = convertUSDPricePointToCurrency(
         assetPricePoint,
-      )
-
-      if (!usdAmount) {
-        return 0
-      }
-
-      const convertedAmount = convertUSDAmountToCurrency(
-        usdAmount,
         displayCurrency,
       )
 
-      if (typeof convertedAmount === "undefined") {
+      const amount = convertAssetAmountViaPricePoint(assetAmount, pricePoint)
+
+      if (typeof amount === "undefined") {
         return 0
       }
 
-      return assetAmountToDesiredDecimals(
-        convertedAmount,
-        desiredDecimals.default,
-      )
+      return assetAmountToDesiredDecimals(amount, desiredDecimals.default)
     })
     .reduce((total, assetBalance) => total + assetBalance, 0)
 
@@ -487,7 +477,7 @@ function getNetworkAccountTotalsByCategory(
         name: name ?? accountData.defaultName,
         avatarURL: avatarURL ?? accountData.defaultAvatar,
         localizedTotalMainCurrencyAmount: formatCurrencyAmount(
-          displayCurrency.symbol,
+          displayCurrency.code,
           getTotalBalance(accountData.balances, prices, displayCurrency),
           desiredDecimals.default,
         ),
@@ -655,7 +645,7 @@ export const getTotalBalanceForOverview = createSelector(
   selectDisplayCurrency,
   (accountsTotal, displayCurrency) =>
     formatCurrencyAmount(
-      displayCurrency.symbol,
+      displayCurrency.code,
       Object.values(accountsTotal).reduce(
         (total, { totals }) =>
           Object.values(totals).reduce((sum, balance) => sum + balance) + total,

background/redux-slices/selectors/uiSelectors.ts

@@ -1,4 +1,5 @@
 import { createSelector } from "@reduxjs/toolkit"
+import { currencies } from "@thesis-co/cent"
 import type { RootState } from ".."
 
 export const selectCurrentNetwork = createSelector(
@@ -49,5 +50,5 @@ export const selectDisplayCurrency = createSelector(
 
 export const selectDisplayCurrencySign = createSelector(
   selectDisplayCurrency,
-  (currency) => currency.sign,
+  (currency) => currencies[currency.code].symbol,
 )

background/redux-slices/tests/assets-utils.unit.test.ts

@@ -1,4 +1,4 @@
-import { MATIC, OPTIMISTIC_ETH, AVAX, ETH, BNB, USD } from "../../constants"
+import { MATIC, OPTIMISTIC_ETH, AVAX, ETH, BNB } from "../../constants"
 import {
   enrichAssetAmountWithMainCurrencyValues,
   formatCurrencyAmount,
@@ -56,7 +56,7 @@ describe(enrichAssetAmountWithMainCurrencyValues, () => {
       assetAmount,
       pricePoint,
       2,
-      USD,
+      { code: "USD", rate: { amount: 1000000n, decimals: 6n } },
     )
 
     expect(result).toMatchObject({

background/redux-slices/ui.ts

@@ -1,11 +1,7 @@
 import { createSlice, createSelector } from "@reduxjs/toolkit"
 import Emittery from "emittery"
 import { AddressOnNetwork } from "../accounts"
-import {
-  DEFAULT_DISPLAY_CURRENCY,
-  ETHEREUM,
-  TEST_NETWORK_BY_CHAIN_ID,
-} from "../constants"
+import { ETHEREUM, TEST_NETWORK_BY_CHAIN_ID } from "../constants"
 import { AnalyticsEvent, OneTimeAnalyticsEvent } from "../lib/posthog"
 import { EVMNetwork } from "../networks"
 import { AnalyticsPreferences, DismissableItem } from "../services/preferences"
@@ -99,7 +95,10 @@ export const initialState: UIState = {
     address: "",
     network: ETHEREUM,
   },
-  displayCurrency: DEFAULT_DISPLAY_CURRENCY,
+  displayCurrency: {
+    code: "USD",
+    rate: { amount: 1_000_000_000_0n, decimals: 10n },
+  },
   initializationLoadingTimeExpired: false,
   settings: defaultSettings,
   snackbarMessage: "",

background/redux-slices/utils/asset-utils.ts

@@ -1,24 +1,25 @@
+import { ExchangeRate, FixedPoint, Money, currencies } from "@thesis-co/cent"
 import {
+  AnyAsset,
   AnyAssetAmount,
+  AssetMetadata,
+  CoinGeckoAsset,
+  DisplayCurrency,
+  FiatCurrency,
+  FungibleAsset,
+  PricePoint,
+  SmartContractFungibleAsset,
+  UnitPricePoint,
   assetAmountToDesiredDecimals,
   convertAssetAmountViaPricePoint,
-  unitPricePointForPricePoint,
   isFungibleAssetAmount,
-  PricePoint,
-  FungibleAsset,
-  UnitPricePoint,
-  AnyAsset,
-  CoinGeckoAsset,
   isSmartContractFungibleAsset,
-  SmartContractFungibleAsset,
-  AssetMetadata,
-  DisplayCurrency,
+  unitPricePointForPricePoint,
 } from "../../assets"
 import {
   BUILT_IN_NETWORK_BASE_ASSETS,
   OPTIMISM,
   POLYGON,
-  USD,
 } from "../../constants"
 import { fromFixedPointNumber } from "../../lib/fixed-point"
 import { sameEVMAddress } from "../../lib/utils"
@@ -203,7 +204,7 @@ export function formatCurrencyAmount(
 export function convertUSDPricePointToCurrency(
   pricePoint: PricePoint,
   currency: DisplayCurrency,
-): PricePoint {
+) {
   const { pair, amounts, time } = pricePoint
   const idx = pricePoint.pair.findIndex((asset) => asset.symbol === "USD")
 
@@ -213,23 +214,35 @@ export function convertUSDPricePointToCurrency(
     time,
   }
 
-  newPricePoint.pair[idx] = currency
-  newPricePoint.amounts[idx] *= currency.rate
+  const { name, code } = currencies[currency.code]
 
-  return newPricePoint
-}
-
-export function convertUSDAmountToCurrency(
-  assetAmount: AnyAssetAmount,
-  currency: DisplayCurrency,
-) {
-  const pricePoint: PricePoint = {
-    pair: [USD, currency],
-    amounts: [1n * 10n ** BigInt(USD.decimals), currency.rate],
-    time: Date.now(),
+  const asset: FiatCurrency = {
+    name,
+    symbol: code,
+    decimals: 10,
   }
 
-  return convertAssetAmountViaPricePoint(assetAmount, pricePoint)
+  const rate = new ExchangeRate({
+    // Keeping 10 decimals ensures we don't lose precision during conversion
+    baseCurrency: { ...currencies[currency.code], decimals: 10n },
+    quoteCurrency: currencies.USD,
+    rate: FixedPoint(currency.rate),
+  })
+
+  newPricePoint.pair[idx] = asset
+  newPricePoint.amounts[idx] = rate
+    .convert(
+      Money({
+        asset: currencies.USD,
+        amount: FixedPoint({
+          amount: newPricePoint.amounts[idx],
+          decimals: 10n,
+        }),
+      }),
+    )
+    .concretize()[0].balance.amount.amount
+
+  return newPricePoint
 }
 
 /**
@@ -269,47 +282,49 @@ export function enrichAssetAmountWithMainCurrencyValues<
   desiredDecimals: number,
   displayCurrency: DisplayCurrency,
 ): T & AssetMainCurrencyAmount {
-  // Converts to USD as price points are in USD
-  const assetAmountInUSD = convertAssetAmountViaPricePoint(
-    assetAmount,
-    assetPricePoint,
-  )
-  const { unitPrice } = unitPricePointForPricePoint(assetPricePoint) ?? {
-    unitPrice: undefined,
-  }
-
-  if (typeof assetAmountInUSD !== "undefined") {
-    const assetAmountInFiatCurrency = convertUSDAmountToCurrency(
-      assetAmountInUSD,
+  if (assetPricePoint) {
+    // Create a temporary pricepoint in the target user currency
+    const currencyPricePoint = convertUSDPricePointToCurrency(
+      assetPricePoint,
       displayCurrency,
-    )!
+    )
 
-    const convertedDecimalValue = assetAmountToDesiredDecimals(
-      assetAmountInFiatCurrency,
-      desiredDecimals,
+    const assetAmountInCurrency = convertAssetAmountViaPricePoint(
+      assetAmount,
+      currencyPricePoint,
     )
-    const unitPriceDecimalValue =
-      typeof unitPrice === "undefined"
-        ? undefined
-        : assetAmountToDesiredDecimals(unitPrice, desiredDecimals)
-
-    return {
-      ...assetAmount,
-      mainCurrencyAmount: convertedDecimalValue,
-      localizedMainCurrencyAmount: formatCurrencyAmount(
-        displayCurrency.symbol,
-        convertedDecimalValue,
+    const { unitPrice } = unitPricePointForPricePoint(currencyPricePoint) ?? {
+      unitPrice: undefined,
+    }
+
+    if (typeof assetAmountInCurrency !== "undefined") {
+      const convertedDecimalValue = assetAmountToDesiredDecimals(
+        assetAmountInCurrency,
         desiredDecimals,
-      ),
-      unitPrice: unitPriceDecimalValue,
-      localizedUnitPrice:
-        typeof unitPriceDecimalValue === "undefined"
+      )
+      const unitPriceDecimalValue =
+        typeof unitPrice === "undefined"
           ? undefined
-          : formatCurrencyAmount(
-              assetAmountInUSD.asset.symbol,
-              unitPriceDecimalValue,
-              desiredDecimals,
-            ),
+          : assetAmountToDesiredDecimals(unitPrice, desiredDecimals)
+
+      return {
+        ...assetAmount,
+        mainCurrencyAmount: convertedDecimalValue,
+        localizedMainCurrencyAmount: formatCurrencyAmount(
+          displayCurrency.code,
+          convertedDecimalValue,
+          desiredDecimals,
+        ),
+        unitPrice: unitPriceDecimalValue,
+        localizedUnitPrice:
+          typeof unitPriceDecimalValue === "undefined"
+            ? undefined
+            : formatCurrencyAmount(
+                assetAmountInCurrency.asset.symbol,
+                unitPriceDecimalValue,
+                desiredDecimals,
+              ),
+      }
     }
   }