[Wallet] Restore mnemonics in any language if default fails (#5825)

### Description

Use the words in the mnemonic to tell which language the mnemonic is actually in and use that to restore the account instead of using the app's language.

### Tested

Manually and there's a unit test as well

### Related issues

- Fixes #5204

### Backwards compatibility

N/A

packages/mobile/src/import/saga.test.ts

@@ -23,12 +23,11 @@ const mockValidSpanishPhrase =
   'tajo fiera asunto tono aroma palma toro caos lobo espada número rato hacha largo pedir cemento urbe tejado volcán mimo grueso juvenil pueblo desvío'
 
 describe('Import wallet saga', () => {
-  const expectSuccessfulSagaWithPhrase = async (phrase: string, language: string) => {
+  const expectSuccessfulSagaWithPhrase = async (phrase: string) => {
     // @ts-ignore
     await expectSaga(importBackupPhraseSaga, { phrase, useEmptyWallet: false })
       .provide([
         [call(waitWeb3LastBlock), true],
-        [select(currentLanguageSelector), language],
         [matchers.call.fn(fetchTokenBalanceInWeiWithRetry), new BigNumber(10)],
         [matchers.call.fn(assignAccountFromPrivateKey), mockAccount],
         [call(storeMnemonic, phrase, mockAccount), true],
@@ -41,11 +40,11 @@ describe('Import wallet saga', () => {
   }
 
   it('imports a valid phrase', async () => {
-    await expectSuccessfulSagaWithPhrase(mockPhraseValid, 'english')
+    await expectSuccessfulSagaWithPhrase(mockPhraseValid)
   })
 
   it('imports a valid spanish phrase', async () => {
-    await expectSuccessfulSagaWithPhrase(mockValidSpanishPhrase, 'español')
+    await expectSuccessfulSagaWithPhrase(mockValidSpanishPhrase)
   })
 
   const expectFailedSagaWithPhrase = async (phrase: string) => {
@@ -64,10 +63,6 @@ describe('Import wallet saga', () => {
     await expectFailedSagaWithPhrase(mockPhraseInvalid)
   })
 
-  it('fails for a phrase in another language', async () => {
-    await expectFailedSagaWithPhrase(mockValidSpanishPhrase)
-  })
-
   it('prevents import of an empty phrase', async () => {
     // @ts-ignore
     await expectSaga(importBackupPhraseSaga, { phrase: mockPhraseValid, useEmptyWallet: false })

packages/mobile/src/import/saga.ts

@@ -2,12 +2,11 @@ import { generateKeys, validateMnemonic } from '@celo/utils/src/account'
 import { privateKeyToAddress } from '@celo/utils/src/address'
 import BigNumber from 'bignumber.js'
 import * as bip39 from 'react-native-bip39'
-import { call, put, select, spawn, takeLeading } from 'redux-saga/effects'
+import { call, put, spawn, takeLeading } from 'redux-saga/effects'
 import { setBackupCompleted } from 'src/account/actions'
 import { showError } from 'src/alert/actions'
 import { ErrorMessages } from 'src/app/ErrorMessages'
-import { currentLanguageSelector } from 'src/app/reducers'
-import { getWordlist, storeMnemonic } from 'src/backup/utils'
+import { storeMnemonic } from 'src/backup/utils'
 import { CURRENCY_ENUM } from 'src/geth/consts'
 import { refreshAllBalances } from 'src/home/actions'
 import { setHasSeenVerificationNux } from 'src/identity/actions'
@@ -30,8 +29,7 @@ export function* importBackupPhraseSaga({ phrase, useEmptyWallet }: ImportBackup
   Logger.debug(TAG + '@importBackupPhraseSaga', 'Importing backup phrase')
   yield call(waitWeb3LastBlock)
   try {
-    const wordlist = getWordlist(yield select(currentLanguageSelector))
-    if (!validateMnemonic(phrase, wordlist, bip39)) {
+    if (!validateMnemonic(phrase, undefined, bip39)) {
       Logger.error(TAG + '@importBackupPhraseSaga', 'Invalid mnemonic')
       yield put(showError(ErrorMessages.INVALID_BACKUP_PHRASE))
       yield put(importBackupPhraseFailure())

packages/utils/src/account.test.ts

@@ -1,4 +1,10 @@
-import { generateKeys, generateMnemonic, MnemonicStrength, validateMnemonic } from './account'
+import {
+  generateKeys,
+  generateMnemonic,
+  MnemonicLanguages,
+  MnemonicStrength,
+  validateMnemonic,
+} from './account'
 
 describe('Mnemonic validation', () => {
   it('should generate 24 word mnemonic', async () => {
@@ -25,6 +31,8 @@ describe('Mnemonic validation', () => {
       'love regular blood road latin uncle shuffle hill aerobic cushion robust million elder gather clip unique pupil escape frost myth glove gadget pitch february',
       'gasp eyebrow sibling dash armed guess excuse ball whip thunder insane pause lizard excuse air catalog tail control raise test dutch permit magic under',
     ]
+    const spanishMnemonic =
+      'avance colmo poema momia cofre pata res verso secta cinco tubería yacer eterno observar ojo tabaco seta ruina bebé oral miembro gato suelo violín'
     const expectedPrivateKeys = [
       {
         derivation0: {
@@ -205,5 +213,7 @@ describe('Mnemonic validation', () => {
       const password = await generateKeys(mnemonics[i], 'password')
       expect({ derivation0, derivation1, password }).toEqual(expectedPrivateKeys[i])
     }
+    expect(validateMnemonic(spanishMnemonic, MnemonicLanguages.english)).toBeFalsy()
+    expect(validateMnemonic(spanishMnemonic)).toBeTruthy()
   })
 })

packages/utils/src/account.ts

@@ -56,10 +56,20 @@ export async function generateMnemonic(
 
 export function validateMnemonic(
   mnemonic: string,
-  language?: MnemonicLanguages,
+  defaultLanguage?: MnemonicLanguages,
   bip39ToUse: Bip39 = bip39Wrapper
 ) {
-  return bip39ToUse.validateMnemonic(mnemonic, getWordList(language))
+  const mnemonicWords = mnemonic.trim().split(' ')
+  const languages = defaultLanguage
+    ? [defaultLanguage]
+    : getAllLanguages().filter((lang) => lang !== defaultLanguage)
+  for (const language of languages) {
+    const wordList = getWordList(language)
+    if (mnemonicWords.every((word) => wordList.includes(word))) {
+      return bip39ToUse.validateMnemonic(mnemonic, getWordList(language))
+    }
+  }
+  return false
 }
 
 export async function generateKeys(
@@ -145,6 +155,19 @@ function getWordList(language?: MnemonicLanguages) {
   }
 }
 
+function getAllLanguages() {
+  return [
+    MnemonicLanguages.chinese_simplified,
+    MnemonicLanguages.chinese_traditional,
+    MnemonicLanguages.english,
+    MnemonicLanguages.french,
+    MnemonicLanguages.italian,
+    MnemonicLanguages.japanese,
+    MnemonicLanguages.korean,
+    MnemonicLanguages.spanish,
+  ]
+}
+
 export const AccountUtils = {
   generateMnemonic,
   validateMnemonic,