Reuse WalletListModal as the Houdini private send picker

Extract the Houdini-only swap-to-address quote construction into a shared
fetchHoudiniPrivateQuote helper and drive the private send destination
selection through the shared WalletListModal (filtered to Houdini's
supported chains) instead of a bespoke asset picker.

Author: j0ntz

src/components/scenes/HoudiniPrivateSendScene.tsx

@@ -1,21 +1,18 @@
-import { div, mul, round } from 'biggystring'
-import type {
-  EdgeCurrencyConfig,
-  EdgeSwapQuote,
-  EdgeSwapRequest,
-  EdgeSwapToAddressInfo,
-  EdgeTokenId
-} from 'edge-core-js'
+import { div, gt, mul, round } from 'biggystring'
+import type { EdgeTokenId } from 'edge-core-js'
 import * as React from 'react'
 
 import { useHandler } from '../../hooks/useHandler'
 import { lstrings } from '../../locales/strings'
+import { getExchangeDenom } from '../../selectors/DenominationSelectors'
 import { useState } from '../../types/reactHooks'
 import { useSelector } from '../../types/reactRedux'
 import type { EdgeAppSceneProps, NavigationBase } from '../../types/routerTypes'
 import { getWalletName } from '../../util/CurrencyWalletHelpers'
 import {
+  fetchHoudiniPrivateQuote,
   HOUDINI_DESTINATION_ASSETS,
+  HOUDINI_DESTINATION_EDGE_ASSETS,
   type HoudiniDestinationAsset,
   isValidHoudiniDestination
 } from '../../util/houdiniPrivateSend'
@@ -24,7 +21,6 @@ import { EdgeCard } from '../cards/EdgeCard'
 import { SceneWrapper } from '../common/SceneWrapper'
 import { SectionHeader } from '../common/SectionHeader'
 import { ConfirmContinueModal } from '../modals/ConfirmContinueModal'
-import { RadioListModal } from '../modals/RadioListModal'
 import { TextInputModal } from '../modals/TextInputModal'
 import {
   WalletListModal,
@@ -37,26 +33,10 @@ import { EdgeText } from '../themed/EdgeText'
 interface Props extends EdgeAppSceneProps<'houdiniPrivateSend'> {}
 
 /**
- * The primary-unit multiplier for an asset, used to convert a user-entered
- * display amount to and from a native (atomic) amount.
- */
-function getPrimaryMultiplier(
-  currencyConfig: EdgeCurrencyConfig,
-  tokenId: EdgeTokenId
-): string {
-  const { allTokens, currencyInfo } = currencyConfig
-  const denominations =
-    tokenId == null
-      ? currencyInfo.denominations
-      : allTokens[tokenId]?.denominations ?? currencyInfo.denominations
-  return denominations[0].multiplier
-}
-
-/**
- * A minimal prototype flow for a Houdini private send: pick a funded source
- * wallet, pick a destination asset from the supported set, paste a destination
- * address, get a live private quote, then create the exchange order and
- * broadcast the on-chain deposit through core's swap-to-address path.
+ * A Houdini private send: pick a funded source wallet, pick a destination asset
+ * (both via the shared `WalletListModal`), paste a destination address, get a
+ * live private quote, then create the exchange order and broadcast the on-chain
+ * deposit through core's swap-to-address path.
  */
 export const HoudiniPrivateSendScene: React.FC<Props> = props => {
   const { navigation } = props
@@ -67,6 +47,9 @@ export const HoudiniPrivateSendScene: React.FC<Props> = props => {
   const currencyWallets = useSelector(
     state => state.core.account.currencyWallets
   )
+  const disablePlugins = useSelector(
+    state => state.ui.exchangeInfo.swap.disablePlugins
+  )
 
   const [fromWalletId, setFromWalletId] = useState<string | undefined>(
     undefined
@@ -103,25 +86,24 @@ export const HoudiniPrivateSendScene: React.FC<Props> = props => {
   })
 
   const handlePickDestAsset = useHandler(async () => {
-    const selected = await Airship.show<string | undefined>(bridge => (
-      <RadioListModal
+    // Reuse the shared wallet picker, filtered to the chains Houdini can
+    // privately route to, so the destination chain is chosen with the same
+    // control as the source rather than a bespoke picker.
+    const result = await Airship.show<WalletListResult>(bridge => (
+      <WalletListModal
         bridge={bridge}
-        title={lstrings.houdini_ps_select_dest_asset}
-        items={HOUDINI_DESTINATION_ASSETS.map(asset => ({
-          icon: '',
-          name: `${asset.displayName} (${asset.currencyCode})`
-        }))}
-        selected={
-          destAsset == null
-            ? undefined
-            : `${destAsset.displayName} (${destAsset.currencyCode})`
-        }
+        // eslint-disable-next-line @typescript-eslint/no-deprecated
+        navigation={navigation as NavigationBase}
+        headerTitle={lstrings.houdini_ps_select_dest_asset}
+        allowedAssets={HOUDINI_DESTINATION_EDGE_ASSETS}
+        showCreateWallet
       />
     ))
-    if (selected == null) return
+    if (result?.type !== 'wallet') return
+    const selectedWallet = currencyWallets[result.walletId]
+    if (selectedWallet == null) return
     const asset = HOUDINI_DESTINATION_ASSETS.find(
-      candidate =>
-        `${candidate.displayName} (${candidate.currencyCode})` === selected
+      candidate => candidate.pluginId === selectedWallet.currencyInfo.pluginId
     )
     if (asset != null) {
       setDestAsset(asset)
@@ -190,49 +172,34 @@ export const HoudiniPrivateSendScene: React.FC<Props> = props => {
     }
     setPending(true)
     try {
-      const fromMultiplier = getPrimaryMultiplier(
+      const fromMultiplier = getExchangeDenom(
         fromWallet.currencyConfig,
         fromTokenId
-      )
+      ).multiplier
       const nativeAmount = round(mul(displayAmount, fromMultiplier), 0)
 
-      const toAddressInfo: EdgeSwapToAddressInfo = {
-        toPluginId: destAsset.pluginId,
-        toAddress
+      // Don't let the user reach confirm/approve with more than they hold.
+      const balance = fromWallet.balanceMap.get(fromTokenId) ?? '0'
+      if (gt(nativeAmount, balance)) {
+        showError(lstrings.exchange_insufficient_funds_below_balance)
+        return
       }
-      const request: EdgeSwapRequest = {
+
+      const quote = await fetchHoudiniPrivateQuote(account, {
         fromWallet,
         fromTokenId,
+        toPluginId: destAsset.pluginId,
         toTokenId: destAsset.tokenId,
-        toAddressInfo,
+        toAddress,
         nativeAmount,
-        quoteFor: 'from'
-      }
-
-      // Restrict the prototype to Houdini: a swap-to-address request would
-      // otherwise fan out to every central provider, creating junk orders and
-      // burning their quotas.
-      const disabled: Record<string, true> = {}
-      for (const pluginId of Object.keys(account.swapConfig)) {
-        if (pluginId !== 'houdini') disabled[pluginId] = true
-      }
-
-      const quotes = await account.fetchSwapQuotes(request, {
-        preferPluginId: 'houdini',
-        disabled
+        disablePlugins
       })
-      // Houdini-only by design: never fall back to another provider's quote, or
-      // the swap-to-address deposit could be routed through the wrong plugin.
-      const quote: EdgeSwapQuote | undefined = quotes.find(
-        candidate => candidate.pluginId === 'houdini'
-      )
-      if (quote == null) {
-        showError(lstrings.houdini_ps_no_quote)
-        return
-      }
 
       const toConfig = account.currencyConfig[destAsset.pluginId]
-      const toMultiplier = getPrimaryMultiplier(toConfig, destAsset.tokenId)
+      const toMultiplier = getExchangeDenom(
+        toConfig,
+        destAsset.tokenId
+      ).multiplier
       const fromDisplay = div(quote.fromNativeAmount, fromMultiplier, 8)
       const toDisplay = div(quote.toNativeAmount, toMultiplier, 8)
 

src/locales/strings/enUS.json

@@ -1446,6 +1446,9 @@
   "houdini_ps_missing_fields": "Select a source wallet, destination asset, address, and amount first",
   "houdini_ps_pick_dest_asset_first": "Select a destination asset first",
   "houdini_ps_pick_source_first": "Select a source wallet first",
+  "houdini_swap_private_label": "Private swap",
+  "houdini_swap_from_amount_only": "Private swaps quote from the send amount only",
+  "houdini_swap_no_dest_address": "Could not get a destination address for the selected wallet",
   "deposit_to_bank": "Deposit to Bank",
   "your_wallets": "Your Wallets",
   "pause_wallet_toast": "This wallet will no longer synchronize with the blockchain and will not detect new transactions or balance changes",

src/util/houdiniPrivateSend.ts

@@ -1,4 +1,14 @@
-import type { EdgeTokenId } from 'edge-core-js'
+import type {
+  EdgeAccount,
+  EdgeCurrencyWallet,
+  EdgeSwapQuote,
+  EdgeSwapRequest,
+  EdgeSwapToAddressInfo,
+  EdgeTokenId
+} from 'edge-core-js'
+
+import { lstrings } from '../locales/strings'
+import type { EdgeAsset } from '../types/types'
 
 /**
  * A destination asset Houdini can privately route a swap to, paired with the
@@ -64,15 +74,16 @@ export const HOUDINI_DESTINATION_ASSETS: HoudiniDestinationAsset[] = [
     tokenId: null,
     currencyCode: 'DASH',
     displayName: 'Dash',
-    addressValidation: /^[X|7][0-9A-Za-z]{33}$/
+    addressValidation: /^[X7][0-9A-Za-z]{33}$/
   },
   {
     pluginId: 'solana',
     tokenId: null,
     currencyCode: 'SOL',
     displayName: 'Solana',
-    addressValidation:
-      /^[1-9A-HJ-NP-SU-Za-hj-np-su-z][1-9A-HJ-NP-Za-km-z]{31,43}$/
+    // Base58, 32-44 chars; every position uses the full Base58 alphabet
+    // (excludes 0, O, I, l).
+    addressValidation: /^[1-9A-HJ-NP-Za-km-z]{32,44}$/
   },
   {
     pluginId: 'tron',
@@ -118,6 +129,16 @@ export const HOUDINI_DESTINATION_ASSETS: HoudiniDestinationAsset[] = [
   }
 ]
 
+/**
+ * The Houdini destination chains expressed as `EdgeAsset`s, for filtering the
+ * shared `WalletListModal` down to the assets Houdini can privately route to.
+ */
+export const HOUDINI_DESTINATION_EDGE_ASSETS: EdgeAsset[] =
+  HOUDINI_DESTINATION_ASSETS.map(asset => ({
+    pluginId: asset.pluginId,
+    tokenId: asset.tokenId
+  }))
+
 /**
  * Validate a pasted destination address against the asset's Houdini regex.
  */
@@ -127,3 +148,81 @@ export function isValidHoudiniDestination(
 ): boolean {
   return asset.addressValidation.test(address.trim())
 }
+
+export interface HoudiniPrivateQuoteParams {
+  fromWallet: EdgeCurrencyWallet
+  fromTokenId: EdgeTokenId
+  toPluginId: string
+  toTokenId: EdgeTokenId
+  toAddress: string
+  nativeAmount: string
+  /**
+   * The `exchangeInfo.swap.disablePlugins` map. If Houdini is disabled
+   * server-side the private path must not invoke it, so a disabled Houdini is
+   * treated as "no private quote available".
+   */
+  disablePlugins?: Readonly<Record<string, unknown>>
+}
+
+/** Whether a plugin is turned off in the exchange-info disable map. */
+export function isPluginDisabled(
+  disablePlugins: Readonly<Record<string, unknown>> | undefined,
+  pluginId: string
+): boolean {
+  return disablePlugins?.[pluginId] === true
+}
+
+/**
+ * Build a Houdini swap-to-address request and fetch a Houdini-only private
+ * quote. Restricting the request to Houdini keeps a swap-to-address quote from
+ * fanning out to every central provider (which would create junk orders and
+ * burn their quotas) and guarantees the on-chain deposit is routed through the
+ * private path rather than another provider's.
+ */
+export async function fetchHoudiniPrivateQuote(
+  account: EdgeAccount,
+  params: HoudiniPrivateQuoteParams
+): Promise<EdgeSwapQuote> {
+  const {
+    fromWallet,
+    fromTokenId,
+    toPluginId,
+    toTokenId,
+    toAddress,
+    nativeAmount,
+    disablePlugins
+  } = params
+
+  // Respect a server-side Houdini disable: the private path is Houdini-only, so
+  // a disabled Houdini means there is no private quote to offer.
+  if (isPluginDisabled(disablePlugins, 'houdini')) {
+    throw new Error(lstrings.houdini_ps_no_quote)
+  }
+
+  // `toAddressInfo` carries only what the request does not already hold: the
+  // address itself and the destination plugin (the token is on the request).
+  const toAddressInfo: EdgeSwapToAddressInfo = { toPluginId, toAddress }
+  const request: EdgeSwapRequest = {
+    fromWallet,
+    fromTokenId,
+    toTokenId,
+    toAddressInfo,
+    nativeAmount,
+    quoteFor: 'from'
+  }
+
+  const disabled: Record<string, true> = {}
+  for (const pluginId of Object.keys(account.swapConfig)) {
+    if (pluginId !== 'houdini') disabled[pluginId] = true
+  }
+
+  const quotes = await account.fetchSwapQuotes(request, {
+    preferPluginId: 'houdini',
+    disabled
+  })
+  const quote = quotes.find(candidate => candidate.pluginId === 'houdini')
+  if (quote == null) {
+    throw new Error(lstrings.houdini_ps_no_quote)
+  }
+  return quote
+}