From 8f4ffdeca456235d805f8cc151b88673493c4715 Mon Sep 17 00:00:00 2001
From: Samuel Holmes <sam@edge.app>
Date: Wed, 25 Oct 2023 17:05:23 -0700
Subject: [PATCH] Detect and warn user for amount changes within transaction
 acceleration

---
 CHANGELOG.md                                |  2 ++
 src/components/modals/AccelerateTxModal.tsx | 18 ++++++++++++++++++
 src/locales/en_US.ts                        |  2 ++
 src/locales/strings/enUS.json               |  2 ++
 4 files changed, 24 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e91a84b8eba..d9d326baf9a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@
 
 ## Unreleased
 
+- added: New 'Lower Send Amount' warning for transaction acceleration
+
 ## 3.21.0
 
 - added: Paybis buy/sell in Brazil, Columbia, and Mexico
diff --git a/src/components/modals/AccelerateTxModal.tsx b/src/components/modals/AccelerateTxModal.tsx
index 2d647202b07..cb1ed32a110 100644
--- a/src/components/modals/AccelerateTxModal.tsx
+++ b/src/components/modals/AccelerateTxModal.tsx
@@ -1,3 +1,4 @@
+import { abs, lt, sub } from 'biggystring'
 import { EdgeCurrencyWallet, EdgeDenomination, EdgeTransaction } from 'edge-core-js'
 import React, { PureComponent } from 'react'
 import { Text, View } from 'react-native'
@@ -8,6 +9,7 @@ import { getDisplayDenominationFromState, getExchangeDenominationFromState } fro
 import { connect } from '../../types/reactRedux'
 import { GuiExchangeRates } from '../../types/types'
 import { convertTransactionFeeToDisplayFee } from '../../util/utils'
+import { WarningCard } from '../cards/WarningCard'
 import { cacheStyles, Theme, ThemeProps, withTheme } from '../services/ThemeContext'
 import { ModalMessage, ModalTitle } from '../themed/ModalParts'
 import { Slider } from '../themed/Slider'
@@ -105,6 +107,7 @@ export class AccelerateTxModalComponent extends PureComponent<Props, State> {
     const oldFee = this.getTxFeeDisplay(replacedTx)
     const newFee = this.getTxFeeDisplay(acceleratedTx)
 
+    const isLowerAmount = lt(getTxSendAmount(acceleratedTx), getTxSendAmount(replacedTx))
     const isSending = status === 'sending'
 
     return (
@@ -115,6 +118,13 @@ export class AccelerateTxModalComponent extends PureComponent<Props, State> {
           <Tile type="static" title={lstrings.transaction_details_accelerate_transaction_old_fee_title} body={oldFee} />
           {newFee == null ? null : <Tile type="static" title={lstrings.transaction_details_accelerate_transaction_new_fee_title} body={newFee} />}
         </View>
+        {isLowerAmount ? (
+          <WarningCard
+            title={lstrings.transaction_details_accelerate_transaction_lower_amount_tx_title}
+            points={[lstrings.transaction_details_accelerate_transaction_lower_amount_tx_message]}
+            marginRem={[1.5, 1]}
+          />
+        ) : null}
         {error == null ? null : (
           <View style={styles.error}>
             <Text style={styles.errorText} numberOfLines={3}>
@@ -169,3 +179,11 @@ export const AccelerateTxModal = connect<StateProps, DispatchProps, OwnProps>(
     }
   })
 )(withTheme(AccelerateTxModalComponent))
+
+function getTxSendAmount(edgeTransaction: EdgeTransaction): string {
+  // Transaction amounts are negative for send transactions
+  const nativeAmount = abs(edgeTransaction.nativeAmount)
+  // Parent network fee is used for token sends
+  const feeAmount = edgeTransaction.parentNetworkFee ?? edgeTransaction.networkFee
+  return sub(nativeAmount, feeAmount)
+}
diff --git a/src/locales/en_US.ts b/src/locales/en_US.ts
index 482c74774f6..e014f414ef6 100644
--- a/src/locales/en_US.ts
+++ b/src/locales/en_US.ts
@@ -664,6 +664,8 @@ const strings = {
   transaction_details_accelerate_transaction_slider_disabled: 'Unable to Accelerate Transaction',
   transaction_details_accelerate_transaction_fee_too_low: 'Accelerated transaction fee is too low. Fee has been updated. Please try again.',
   transaction_details_accelerate_transaction_sent: 'Your transaction has been accelerated.',
+  transaction_details_accelerate_transaction_lower_amount_tx_title: 'Lower Send Amount',
+  transaction_details_accelerate_transaction_lower_amount_tx_message: `In order to accelerate this transaction, the recipient's amount will be lower due to insufficient balance to cover the new fee.`,
   transaction_details_exchange_details: 'Exchange Details',
   transaction_details_exchange_service: 'Exchange Service',
   transaction_details_exchange_order_id: 'Order ID',
diff --git a/src/locales/strings/enUS.json b/src/locales/strings/enUS.json
index 479517ba1ab..8e5cba5ca7c 100644
--- a/src/locales/strings/enUS.json
+++ b/src/locales/strings/enUS.json
@@ -595,6 +595,8 @@
   "transaction_details_accelerate_transaction_slider_disabled": "Unable to Accelerate Transaction",
   "transaction_details_accelerate_transaction_fee_too_low": "Accelerated transaction fee is too low. Fee has been updated. Please try again.",
   "transaction_details_accelerate_transaction_sent": "Your transaction has been accelerated.",
+  "transaction_details_accelerate_transaction_lower_amount_tx_title": "Lower Send Amount",
+  "transaction_details_accelerate_transaction_lower_amount_tx_message": "In order to accelerate this transaction, the recipient's amount will be lower due to insufficient balance to cover the new fee.",
   "transaction_details_exchange_details": "Exchange Details",
   "transaction_details_exchange_service": "Exchange Service",
   "transaction_details_exchange_order_id": "Order ID",