diff --git a/lib/utils/olm-utils.js b/lib/utils/olm-utils.js
index 5c93c1001..b4e4588d2 100644
--- a/lib/utils/olm-utils.js
+++ b/lib/utils/olm-utils.js
@@ -1,152 +1,158 @@
 // @flow
 
 import type { Account as OlmAccount } from '@commapp/olm';
 
 import {
   getOneTimeKeyValuesFromBlob,
   getPrekeyValueFromBlob,
 } from '../shared/crypto-utils.js';
 import { ONE_TIME_KEYS_NUMBER } from '../types/identity-service-types.js';
 
 const maxPublishedPrekeyAge = 30 * 24 * 60 * 60 * 1000;
 const maxOldPrekeyAge = 24 * 60 * 60 * 1000;
 
 type AccountKeysSet = {
   +identityKeys: string,
   +prekey: string,
   +prekeySignature: string,
   +oneTimeKeys: $ReadOnlyArray<string>,
 };
 
 type IdentityKeysAndPrekeys = {
   +identityKeys: string,
   +prekey: string,
   +prekeySignature: string,
 };
 
 function validateAccountPrekey(account: OlmAccount) {
   if (shouldRotatePrekey(account)) {
     account.generate_prekey();
   }
   if (shouldForgetPrekey(account)) {
     account.forget_old_prekey();
   }
 }
 
 function shouldRotatePrekey(account: OlmAccount): boolean {
   // Our fork of Olm only remembers two prekeys at a time.
   // If the new one hasn't been published, then the old one is still active.
   // In that scenario, we need to avoid rotating the prekey because it will
   // result in the old active prekey being discarded.
   if (account.unpublished_prekey()) {
     return false;
   }
 
   const currentDate = new Date();
   const lastPrekeyPublishDate = getLastPrekeyPublishTime(account);
 
   return (
     currentDate.getTime() - lastPrekeyPublishDate.getTime() >=
     maxPublishedPrekeyAge
   );
 }
 
 function shouldForgetPrekey(account: OlmAccount): boolean {
   // Our fork of Olm only remembers two prekeys at a time.
   // We have to hold onto the old one until the new one is published.
   if (account.unpublished_prekey()) {
     return false;
   }
 
   const currentDate = new Date();
   const lastPrekeyPublishDate = getLastPrekeyPublishTime(account);
 
   return (
     currentDate.getTime() - lastPrekeyPublishDate.getTime() >= maxOldPrekeyAge
   );
 }
 
 function getLastPrekeyPublishTime(account: OlmAccount): Date {
   const olmLastPrekeyPublishTime = account.last_prekey_publish_time();
 
   // Olm uses seconds, while the Date() constructor expects milliseconds.
   return new Date(olmLastPrekeyPublishTime * 1000);
 }
 
 function getAccountPrekeysSet(account: OlmAccount): {
   +prekey: string,
   +prekeySignature: ?string,
 } {
   const prekey = getPrekeyValueFromBlob(account.prekey());
   const prekeySignature = account.prekey_signature();
   return { prekey, prekeySignature };
 }
 
 function getAccountOneTimeKeys(
   account: OlmAccount,
   numberOfKeys: number = ONE_TIME_KEYS_NUMBER,
 ): $ReadOnlyArray<string> {
   let oneTimeKeys = getOneTimeKeyValuesFromBlob(account.one_time_keys());
   if (oneTimeKeys.length < numberOfKeys) {
     account.generate_one_time_keys(numberOfKeys - oneTimeKeys.length);
     oneTimeKeys = getOneTimeKeyValuesFromBlob(account.one_time_keys());
   }
   return oneTimeKeys;
 }
 
 function retrieveAccountKeysSet(account: OlmAccount): AccountKeysSet {
   const { identityKeys, prekey, prekeySignature } =
     retrieveIdentityKeysAndPrekeys(account);
   const oneTimeKeys = getAccountOneTimeKeys(account, ONE_TIME_KEYS_NUMBER);
   return { identityKeys, oneTimeKeys, prekey, prekeySignature };
 }
 
 function retrieveIdentityKeysAndPrekeys(
   account: OlmAccount,
 ): IdentityKeysAndPrekeys {
   const identityKeys = account.identity_keys();
 
   validateAccountPrekey(account);
   const { prekey, prekeySignature } = getAccountPrekeysSet(account);
 
   if (!prekeySignature || !prekey) {
     throw new Error('invalid_prekey');
   }
 
   return { identityKeys, prekey, prekeySignature };
 }
 
 const olmSessionErrors = Object.freeze({
   // Two clients send the session request to each other at the same time,
   // we choose which session to keep based on `deviceID`.
   raceCondition: 'OLM_SESSION_CREATION_RACE_CONDITION',
   // The client received a session request with a lower session version,
   // this request can be ignored.
   alreadyCreated: 'OLM_SESSION_ALREADY_CREATED',
   // If using sequential decrypt this error means that message was decrypted.
   // Otherwise, it could mean that the receiver chain advance beyond and the key
   // to decrypt that message was discarded.
   messageAlreadyDecrypted: 'OLM_ALREADY_DECRYPTED_OR_KEYS_SKIPPED',
+  // Error thrown when attempting to encrypt/decrypt, indicating that
+  // the session for a given deviceID is not created.
+  // This definition should remain in sync with the value defined in
+  // the corresponding .cpp file
+  // at `native/cpp/CommonCpp/CryptoTools/CryptoModule.cpp`.
+  sessionDoesNotExists: 'SESSION_DOES_NOT_EXISTS',
 });
 
 function hasHigherDeviceID(
   currenDeviceID: string,
   otherDeviceID: string,
 ): boolean {
   const compareResult = currenDeviceID.localeCompare(otherDeviceID);
   if (compareResult === 0) {
     throw new Error('Comparing the same deviceIDs');
   }
   return compareResult === 1;
 }
 
 export {
   retrieveAccountKeysSet,
   getAccountPrekeysSet,
   shouldForgetPrekey,
   shouldRotatePrekey,
   getAccountOneTimeKeys,
   retrieveIdentityKeysAndPrekeys,
   hasHigherDeviceID,
   olmSessionErrors,
 };
diff --git a/native/cpp/CommonCpp/CryptoTools/CryptoModule.cpp b/native/cpp/CommonCpp/CryptoTools/CryptoModule.cpp
index 454cc5881..8fe5fcfbb 100644
--- a/native/cpp/CommonCpp/CryptoTools/CryptoModule.cpp
+++ b/native/cpp/CommonCpp/CryptoTools/CryptoModule.cpp
@@ -1,456 +1,460 @@
 #include "CryptoModule.h"
 #include "Logger.h"
 #include "PlatformSpecificTools.h"
 #include "olm/account.hh"
 #include "olm/session.hh"
 
 #include <folly/dynamic.h>
 #include <folly/json.h>
 #include <ctime>
 #include <stdexcept>
 
 namespace comm {
 namespace crypto {
 
+// This definition should remain in sync with the value defined in
+// the corresponding JavaScript file at `lib/utils/olm-utils.js`.
+const std::string SESSION_DOES_NOT_EXISTS_ERROR{"SESSION_DOES_NOT_EXISTS"};
+
 CryptoModule::CryptoModule(std::string id) : id{id} {
   this->createAccount();
 }
 
 CryptoModule::CryptoModule(
     std::string id,
     std::string secretKey,
     Persist persist)
     : id{id} {
   if (persist.isEmpty()) {
     this->createAccount();
   } else {
     this->restoreFromB64(secretKey, persist);
   }
 }
 
 OlmAccount *CryptoModule::getOlmAccount() {
   return reinterpret_cast<OlmAccount *>(this->accountBuffer.data());
 }
 
 void CryptoModule::createAccount() {
   this->accountBuffer.resize(::olm_account_size());
   ::olm_account(this->accountBuffer.data());
 
   size_t randomSize = ::olm_create_account_random_length(this->getOlmAccount());
   OlmBuffer randomBuffer;
   PlatformSpecificTools::generateSecureRandomBytes(randomBuffer, randomSize);
 
   if (-1 ==
       ::olm_create_account(
           this->getOlmAccount(), randomBuffer.data(), randomSize)) {
     throw std::runtime_error{
         "error createAccount => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   };
 }
 
 void CryptoModule::exposePublicIdentityKeys() {
   size_t identityKeysSize =
       ::olm_account_identity_keys_length(this->getOlmAccount());
   if (this->keys.identityKeys.size() == identityKeysSize) {
     return;
   }
   this->keys.identityKeys.resize(
       ::olm_account_identity_keys_length(this->getOlmAccount()));
   if (-1 ==
       ::olm_account_identity_keys(
           this->getOlmAccount(),
           this->keys.identityKeys.data(),
           this->keys.identityKeys.size())) {
     throw std::runtime_error{
         "error generateIdentityKeys => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
 }
 
 void CryptoModule::generateOneTimeKeys(size_t oneTimeKeysAmount) {
   size_t numRandomBytesRequired =
       ::olm_account_generate_one_time_keys_random_length(
           this->getOlmAccount(), oneTimeKeysAmount);
   OlmBuffer random;
   PlatformSpecificTools::generateSecureRandomBytes(
       random, numRandomBytesRequired);
 
   if (-1 ==
       ::olm_account_generate_one_time_keys(
           this->getOlmAccount(),
           oneTimeKeysAmount,
           random.data(),
           random.size())) {
     throw std::runtime_error{
         "error generateOneTimeKeys => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
 }
 
 // returns number of published keys
 size_t CryptoModule::publishOneTimeKeys() {
   this->keys.oneTimeKeys.resize(
       ::olm_account_one_time_keys_length(this->getOlmAccount()));
   if (-1 ==
       ::olm_account_one_time_keys(
           this->getOlmAccount(),
           this->keys.oneTimeKeys.data(),
           this->keys.oneTimeKeys.size())) {
     throw std::runtime_error{
         "error publishOneTimeKeys => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
   return ::olm_account_mark_keys_as_published(this->getOlmAccount());
 }
 
 bool CryptoModule::prekeyExistsAndOlderThan(uint64_t threshold) {
   // Our fork of Olm only remembers two prekeys at a time.
   // If the new one hasn't been published, then the old one is still active.
   // In that scenario, we need to avoid rotating the prekey because it will
   // result in the old active prekey being discarded.
   if (this->getUnpublishedPrekey().has_value()) {
     return false;
   }
 
   uint64_t currentTime = std::time(nullptr);
   uint64_t lastPrekeyPublishTime =
       ::olm_account_get_last_prekey_publish_time(this->getOlmAccount());
 
   return currentTime - lastPrekeyPublishTime >= threshold;
 }
 
 Keys CryptoModule::keysFromStrings(
     const std::string &identityKeys,
     const std::string &oneTimeKeys) {
   return {
       OlmBuffer(identityKeys.begin(), identityKeys.end()),
       OlmBuffer(oneTimeKeys.begin(), oneTimeKeys.end())};
 }
 
 std::string CryptoModule::getIdentityKeys() {
   this->exposePublicIdentityKeys();
   return std::string{
       this->keys.identityKeys.begin(), this->keys.identityKeys.end()};
 }
 
 std::string
 CryptoModule::getOneTimeKeysForPublishing(size_t oneTimeKeysAmount) {
   OlmBuffer unpublishedOneTimeKeys;
   unpublishedOneTimeKeys.resize(
       ::olm_account_one_time_keys_length(this->getOlmAccount()));
   if (-1 ==
       ::olm_account_one_time_keys(
           this->getOlmAccount(),
           unpublishedOneTimeKeys.data(),
           unpublishedOneTimeKeys.size())) {
     throw std::runtime_error{
         "error getOneTimeKeysForPublishing => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
   std::string unpublishedKeysString =
       std::string{unpublishedOneTimeKeys.begin(), unpublishedOneTimeKeys.end()};
 
   folly::dynamic parsedUnpublishedKeys =
       folly::parseJson(unpublishedKeysString);
 
   size_t numUnpublishedKeys = parsedUnpublishedKeys["curve25519"].size();
 
   if (numUnpublishedKeys < oneTimeKeysAmount) {
     this->generateOneTimeKeys(oneTimeKeysAmount - numUnpublishedKeys);
   }
 
   this->publishOneTimeKeys();
 
   return std::string{
       this->keys.oneTimeKeys.begin(), this->keys.oneTimeKeys.end()};
 }
 
 std::uint8_t CryptoModule::getNumPrekeys() {
   return reinterpret_cast<olm::Account *>(this->getOlmAccount())->num_prekeys;
 }
 
 std::string CryptoModule::getPrekey() {
   OlmBuffer prekey;
   prekey.resize(::olm_account_prekey_length(this->getOlmAccount()));
 
   if (-1 ==
       ::olm_account_prekey(
           this->getOlmAccount(), prekey.data(), prekey.size())) {
     throw std::runtime_error{
         "error getPrekey => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
 
   return std::string{std::string{prekey.begin(), prekey.end()}};
 }
 
 std::string CryptoModule::getPrekeySignature() {
   size_t signatureSize = ::olm_account_signature_length(this->getOlmAccount());
 
   OlmBuffer signatureBuffer;
   signatureBuffer.resize(signatureSize);
 
   if (-1 ==
       ::olm_account_prekey_signature(
           this->getOlmAccount(), signatureBuffer.data())) {
     throw std::runtime_error{
         "error getPrekeySignature => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
 
   return std::string{signatureBuffer.begin(), signatureBuffer.end()};
 }
 
 std::optional<std::string> CryptoModule::getUnpublishedPrekey() {
   OlmBuffer prekey;
   prekey.resize(::olm_account_prekey_length(this->getOlmAccount()));
 
   std::size_t retval = ::olm_account_unpublished_prekey(
       this->getOlmAccount(), prekey.data(), prekey.size());
 
   if (0 == retval) {
     return std::nullopt;
   } else if (-1 == retval) {
     throw std::runtime_error{
         "error getUnpublishedPrekey => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
 
   return std::string{prekey.begin(), prekey.end()};
 }
 
 std::string CryptoModule::generateAndGetPrekey() {
   size_t prekeySize =
       ::olm_account_generate_prekey_random_length(this->getOlmAccount());
 
   OlmBuffer random;
   PlatformSpecificTools::generateSecureRandomBytes(random, prekeySize);
 
   if (-1 ==
       ::olm_account_generate_prekey(
           this->getOlmAccount(), random.data(), random.size())) {
     throw std::runtime_error{
         "error generateAndGetPrekey => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
 
   OlmBuffer prekey;
   prekey.resize(::olm_account_prekey_length(this->getOlmAccount()));
 
   if (-1 ==
       ::olm_account_prekey(
           this->getOlmAccount(), prekey.data(), prekey.size())) {
     throw std::runtime_error{
         "error generateAndGetPrekey => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
 
   return std::string{prekey.begin(), prekey.end()};
 }
 
 void CryptoModule::markPrekeyAsPublished() {
   ::olm_account_mark_prekey_as_published(this->getOlmAccount());
 }
 
 void CryptoModule::forgetOldPrekey() {
   ::olm_account_forget_old_prekey(this->getOlmAccount());
 }
 
 void CryptoModule::initializeInboundForReceivingSession(
     const std::string &targetDeviceId,
     const OlmBuffer &encryptedMessage,
     const OlmBuffer &idKeys,
     int sessionVersion,
     const bool overwrite) {
   if (this->hasSessionFor(targetDeviceId)) {
     std::shared_ptr<Session> existingSession =
         getSessionByDeviceId(targetDeviceId);
     if (existingSession->getVersion() > sessionVersion) {
       throw std::runtime_error{"OLM_SESSION_ALREADY_CREATED"};
     } else if (existingSession->getVersion() == sessionVersion) {
       throw std::runtime_error{"OLM_SESSION_CREATION_RACE_CONDITION"};
     }
 
     this->sessions.erase(this->sessions.find(targetDeviceId));
   }
   std::unique_ptr<Session> newSession = Session::createSessionAsResponder(
       this->getOlmAccount(),
       this->keys.identityKeys.data(),
       encryptedMessage,
       idKeys);
   newSession->setVersion(sessionVersion);
   this->sessions.insert(make_pair(targetDeviceId, std::move(newSession)));
 }
 
 int CryptoModule::initializeOutboundForSendingSession(
     const std::string &targetDeviceId,
     const OlmBuffer &idKeys,
     const OlmBuffer &preKeys,
     const OlmBuffer &preKeySignature,
     const std::optional<OlmBuffer> &oneTimeKey) {
   int newSessionVersion = 1;
   if (this->hasSessionFor(targetDeviceId)) {
     std::shared_ptr<Session> existingSession =
         getSessionByDeviceId(targetDeviceId);
     newSessionVersion = existingSession->getVersion() + 1;
     Logger::log(
         "olm session overwritten for the device with id: " + targetDeviceId);
     this->sessions.erase(this->sessions.find(targetDeviceId));
   }
   std::unique_ptr<Session> newSession = Session::createSessionAsInitializer(
       this->getOlmAccount(),
       this->keys.identityKeys.data(),
       idKeys,
       preKeys,
       preKeySignature,
       oneTimeKey);
   newSession->setVersion(newSessionVersion);
   this->sessions.insert(make_pair(targetDeviceId, std::move(newSession)));
   return newSessionVersion;
 }
 
 bool CryptoModule::hasSessionFor(const std::string &targetDeviceId) {
   return (this->sessions.find(targetDeviceId) != this->sessions.end());
 }
 
 std::shared_ptr<Session>
 CryptoModule::getSessionByDeviceId(const std::string &deviceId) {
   return this->sessions.at(deviceId);
 }
 
 void CryptoModule::removeSessionByDeviceId(const std::string &deviceId) {
   this->sessions.erase(deviceId);
 }
 
 Persist CryptoModule::storeAsB64(const std::string &secretKey) {
   Persist persist;
   size_t accountPickleLength =
       ::olm_pickle_account_length(this->getOlmAccount());
   OlmBuffer accountPickleBuffer(accountPickleLength);
   if (accountPickleLength !=
       ::olm_pickle_account(
           this->getOlmAccount(),
           secretKey.data(),
           secretKey.size(),
           accountPickleBuffer.data(),
           accountPickleLength)) {
     throw std::runtime_error{
         "error storeAsB64 => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
   persist.account = accountPickleBuffer;
 
   std::unordered_map<std::string, std::shared_ptr<Session>>::iterator it;
   for (it = this->sessions.begin(); it != this->sessions.end(); ++it) {
     OlmBuffer buffer = it->second->storeAsB64(secretKey);
     SessionPersist sessionPersist{buffer, it->second->getVersion()};
     persist.sessions.insert(make_pair(it->first, sessionPersist));
   }
 
   return persist;
 }
 
 void CryptoModule::restoreFromB64(
     const std::string &secretKey,
     Persist persist) {
   this->accountBuffer.resize(::olm_account_size());
   ::olm_account(this->accountBuffer.data());
   if (-1 ==
       ::olm_unpickle_account(
           this->getOlmAccount(),
           secretKey.data(),
           secretKey.size(),
           persist.account.data(),
           persist.account.size())) {
     throw std::runtime_error{
         "error restoreFromB64 => " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
 
   std::unordered_map<std::string, SessionPersist>::iterator it;
   for (it = persist.sessions.begin(); it != persist.sessions.end(); ++it) {
     std::unique_ptr<Session> session =
         session->restoreFromB64(secretKey, it->second.buffer);
     session->setVersion(it->second.version);
     this->sessions.insert(make_pair(it->first, move(session)));
   }
 }
 
 EncryptedData CryptoModule::encrypt(
     const std::string &targetDeviceId,
     const std::string &content) {
   if (!this->hasSessionFor(targetDeviceId)) {
-    throw std::runtime_error{"error encrypt => uninitialized session"};
+    throw std::runtime_error{SESSION_DOES_NOT_EXISTS_ERROR};
   }
   return this->sessions.at(targetDeviceId)->encrypt(content);
 }
 
 std::string CryptoModule::decrypt(
     const std::string &targetDeviceId,
     EncryptedData &encryptedData) {
   if (!this->hasSessionFor(targetDeviceId)) {
-    throw std::runtime_error{"error decrypt => uninitialized session"};
+    throw std::runtime_error{SESSION_DOES_NOT_EXISTS_ERROR};
   }
   return this->sessions.at(targetDeviceId)->decrypt(encryptedData);
 }
 
 std::string CryptoModule::signMessage(const std::string &message) {
   OlmBuffer signature;
   signature.resize(::olm_account_signature_length(this->getOlmAccount()));
   size_t signatureLength = ::olm_account_sign(
       this->getOlmAccount(),
       (uint8_t *)message.data(),
       message.length(),
       signature.data(),
       signature.size());
   if (signatureLength == -1) {
     throw std::runtime_error{
         "olm error: " +
         std::string{::olm_account_last_error(this->getOlmAccount())}};
   }
   return std::string{(char *)signature.data(), signatureLength};
 }
 
 void CryptoModule::verifySignature(
     const std::string &publicKey,
     const std::string &message,
     const std::string &signature) {
   OlmBuffer utilityBuffer;
   utilityBuffer.resize(::olm_utility_size());
   OlmUtility *olmUtility = ::olm_utility(utilityBuffer.data());
   ssize_t verificationResult = ::olm_ed25519_verify(
       olmUtility,
       (uint8_t *)publicKey.data(),
       publicKey.length(),
       (uint8_t *)message.data(),
       message.length(),
       (uint8_t *)signature.data(),
       signature.length());
   if (verificationResult == -1) {
     throw std::runtime_error{
         "olm error: " + std::string{::olm_utility_last_error(olmUtility)}};
   }
 }
 
 std::optional<std::string> CryptoModule::validatePrekey() {
   static const uint64_t maxPrekeyPublishTime = 10 * 60;
   static const uint64_t maxOldPrekeyAge = 2 * 60;
   std::optional<std::string> maybeNewPrekey;
 
   bool shouldRotatePrekey =
       this->prekeyExistsAndOlderThan(maxPrekeyPublishTime);
   if (shouldRotatePrekey) {
     maybeNewPrekey = this->generateAndGetPrekey();
   }
 
   bool shouldForgetPrekey = this->prekeyExistsAndOlderThan(maxOldPrekeyAge);
   if (shouldForgetPrekey) {
     this->forgetOldPrekey();
   }
 
   return maybeNewPrekey;
 }
 
 } // namespace crypto
 } // namespace comm
diff --git a/web/shared-worker/worker/worker-crypto.js b/web/shared-worker/worker/worker-crypto.js
index 6e11c7bd9..9bdee7df3 100644
--- a/web/shared-worker/worker/worker-crypto.js
+++ b/web/shared-worker/worker/worker-crypto.js
@@ -1,1011 +1,1011 @@
 // @flow
 
 import olm, { type Utility } from '@commapp/olm';
 import localforage from 'localforage';
 import uuid from 'uuid';
 
 import { initialEncryptedMessageContent } from 'lib/shared/crypto-utils.js';
 import { hasMinCodeVersion } from 'lib/shared/version-utils.js';
 import {
   type OLMIdentityKeys,
   type PickledOLMAccount,
   type IdentityKeysBlob,
   type SignedIdentityKeysBlob,
   type OlmAPI,
   type OneTimeKeysResultValues,
   type ClientPublicKeys,
   type NotificationsOlmDataType,
   type EncryptedData,
   type OutboundSessionCreationResult,
 } from 'lib/types/crypto-types.js';
 import type { PlatformDetails } from 'lib/types/device-types.js';
 import type {
   IdentityNewDeviceKeyUpload,
   IdentityExistingDeviceKeyUpload,
 } from 'lib/types/identity-service-types.js';
 import type { OlmSessionInitializationInfo } from 'lib/types/request-types.js';
 import type { InboundP2PMessage } from 'lib/types/sqlite-types.js';
 import { getMessageForException } from 'lib/utils/errors.js';
 import { entries } from 'lib/utils/objects.js';
 import {
   retrieveAccountKeysSet,
   getAccountOneTimeKeys,
   getAccountPrekeysSet,
   shouldForgetPrekey,
   shouldRotatePrekey,
   retrieveIdentityKeysAndPrekeys,
   olmSessionErrors,
 } from 'lib/utils/olm-utils.js';
 
 import { getIdentityClient } from './identity-client.js';
 import { getProcessingStoreOpsExceptionMessage } from './process-operations.js';
 import {
   getDBModule,
   getSQLiteQueryExecutor,
   getPlatformDetails,
 } from './worker-database.js';
 import {
   getOlmDataKeyForCookie,
   getOlmEncryptionKeyDBLabelForCookie,
   getOlmDataKeyForDeviceID,
   getOlmEncryptionKeyDBLabelForDeviceID,
   encryptNotification,
   type NotificationAccountWithPicklingKey,
   getNotifsCryptoAccount,
   persistNotifsAccountWithOlmData,
 } from '../../push-notif/notif-crypto-utils.js';
 import {
   type WorkerRequestMessage,
   type WorkerResponseMessage,
   workerRequestMessageTypes,
   workerResponseMessageTypes,
   type LegacyCryptoStore,
 } from '../../types/worker-types.js';
 import type { OlmPersistSession } from '../types/sqlite-query-executor.js';
 
 type OlmSession = { +session: olm.Session, +version: number };
 type OlmSessions = {
   [deviceID: string]: OlmSession,
 };
 
 type WorkerCryptoStore = {
   +contentAccountPickleKey: string,
   +contentAccount: olm.Account,
   +contentSessions: OlmSessions,
 };
 
 let cryptoStore: ?WorkerCryptoStore = null;
 let olmUtility: ?Utility = null;
 
 function clearCryptoStore() {
   cryptoStore = null;
 }
 
 async function persistCryptoStore(
   notifsCryptoAccount?: NotificationAccountWithPicklingKey,
   withoutTransaction: boolean = false,
 ) {
   const sqliteQueryExecutor = getSQLiteQueryExecutor();
   const dbModule = getDBModule();
   if (!sqliteQueryExecutor || !dbModule) {
     throw new Error(
       "Couldn't persist crypto store because database is not initialized",
     );
   }
   if (!cryptoStore) {
     throw new Error("Couldn't persist crypto store because it doesn't exist");
   }
 
   const { contentAccountPickleKey, contentAccount, contentSessions } =
     cryptoStore;
 
   const pickledContentAccount: PickledOLMAccount = {
     picklingKey: contentAccountPickleKey,
     pickledAccount: contentAccount.pickle(contentAccountPickleKey),
   };
 
   const pickledContentSessions: OlmPersistSession[] = entries(
     contentSessions,
   ).map(([targetDeviceID, sessionData]) => ({
     targetDeviceID,
     sessionData: sessionData.session.pickle(contentAccountPickleKey),
     version: sessionData.version,
   }));
 
   try {
     if (!withoutTransaction) {
       sqliteQueryExecutor.beginTransaction();
     }
     sqliteQueryExecutor.storeOlmPersistAccount(
       sqliteQueryExecutor.getContentAccountID(),
       JSON.stringify(pickledContentAccount),
     );
     for (const pickledSession of pickledContentSessions) {
       sqliteQueryExecutor.storeOlmPersistSession(pickledSession);
     }
     if (notifsCryptoAccount) {
       const {
         notificationAccount,
         picklingKey,
         synchronizationValue,
         accountEncryptionKey,
       } = notifsCryptoAccount;
 
       const pickledAccount = notificationAccount.pickle(picklingKey);
       const accountWithPicklingKey: PickledOLMAccount = {
         pickledAccount,
         picklingKey,
       };
 
       await persistNotifsAccountWithOlmData({
         accountEncryptionKey,
         accountWithPicklingKey,
         synchronizationValue,
         forceWrite: true,
       });
     }
     if (!withoutTransaction) {
       sqliteQueryExecutor.commitTransaction();
     }
   } catch (err) {
     if (!withoutTransaction) {
       sqliteQueryExecutor.rollbackTransaction();
     }
     throw new Error(getProcessingStoreOpsExceptionMessage(err, dbModule));
   }
 }
 
 async function createAndPersistNotificationsOutboundSession(
   notificationsIdentityKeys: OLMIdentityKeys,
   notificationsInitializationInfo: OlmSessionInitializationInfo,
   dataPersistenceKey: string,
   dataEncryptionKeyDBLabel: string,
 ): Promise<EncryptedData> {
   if (!cryptoStore) {
     throw new Error('Crypto account not initialized');
   }
 
   const notificationAccountWithPicklingKey = await getNotifsCryptoAccount();
   const {
     notificationAccount,
     picklingKey,
     synchronizationValue,
     accountEncryptionKey,
   } = notificationAccountWithPicklingKey;
 
   const notificationsPrekey = notificationsInitializationInfo.prekey;
   const session = new olm.Session();
   if (notificationsInitializationInfo.oneTimeKey) {
     session.create_outbound(
       notificationAccount,
       notificationsIdentityKeys.curve25519,
       notificationsIdentityKeys.ed25519,
       notificationsPrekey,
       notificationsInitializationInfo.prekeySignature,
       notificationsInitializationInfo.oneTimeKey,
     );
   } else {
     session.create_outbound_without_otk(
       notificationAccount,
       notificationsIdentityKeys.curve25519,
       notificationsIdentityKeys.ed25519,
       notificationsPrekey,
       notificationsInitializationInfo.prekeySignature,
     );
   }
   const { body: message, type: messageType } = session.encrypt(
     JSON.stringify(initialEncryptedMessageContent),
   );
 
   const mainSession = session.pickle(
     notificationAccountWithPicklingKey.picklingKey,
   );
   const notificationsOlmData: NotificationsOlmDataType = {
     mainSession,
     pendingSessionUpdate: mainSession,
     updateCreationTimestamp: Date.now(),
     picklingKey,
   };
 
   const pickledAccount = notificationAccount.pickle(picklingKey);
   const accountWithPicklingKey: PickledOLMAccount = {
     pickledAccount,
     picklingKey,
   };
 
   await persistNotifsAccountWithOlmData({
     accountEncryptionKey,
     accountWithPicklingKey,
     olmDataKey: dataPersistenceKey,
     olmData: notificationsOlmData,
     olmEncryptionKeyDBLabel: dataEncryptionKeyDBLabel,
     synchronizationValue,
     forceWrite: true,
   });
 
   return { message, messageType };
 }
 
 async function getOrCreateOlmAccount(accountIDInDB: number): Promise<{
   +picklingKey: string,
   +account: olm.Account,
   +synchronizationValue?: ?string,
 }> {
   const sqliteQueryExecutor = getSQLiteQueryExecutor();
   const dbModule = getDBModule();
   if (!sqliteQueryExecutor || !dbModule) {
     throw new Error('Database not initialized');
   }
 
   const account = new olm.Account();
   let picklingKey;
 
   let accountDBString;
   try {
     accountDBString =
       sqliteQueryExecutor.getOlmPersistAccountDataWeb(accountIDInDB);
   } catch (err) {
     throw new Error(getProcessingStoreOpsExceptionMessage(err, dbModule));
   }
 
   const maybeNotifsCryptoAccount: ?NotificationAccountWithPicklingKey =
     await (async () => {
       if (accountIDInDB !== sqliteQueryExecutor.getNotifsAccountID()) {
         return undefined;
       }
       try {
         return await getNotifsCryptoAccount();
       } catch (e) {
         return undefined;
       }
     })();
 
   if (maybeNotifsCryptoAccount) {
     const {
       notificationAccount,
       picklingKey: notificationAccountPicklingKey,
       synchronizationValue,
     } = maybeNotifsCryptoAccount;
     return {
       account: notificationAccount,
       picklingKey: notificationAccountPicklingKey,
       synchronizationValue,
     };
   }
 
   if (accountDBString.isNull) {
     picklingKey = uuid.v4();
     account.create();
   } else {
     const dbAccount: PickledOLMAccount = JSON.parse(accountDBString.value);
     picklingKey = dbAccount.picklingKey;
     account.unpickle(picklingKey, dbAccount.pickledAccount);
   }
 
   if (accountIDInDB === sqliteQueryExecutor.getNotifsAccountID()) {
     return { picklingKey, account, synchronizationValue: uuid.v4() };
   }
 
   return { picklingKey, account };
 }
 
 function getOlmSessions(picklingKey: string): OlmSessions {
   const sqliteQueryExecutor = getSQLiteQueryExecutor();
   const dbModule = getDBModule();
   if (!sqliteQueryExecutor || !dbModule) {
     throw new Error(
       "Couldn't get olm sessions because database is not initialized",
     );
   }
 
   let dbSessionsData;
   try {
     dbSessionsData = sqliteQueryExecutor.getOlmPersistSessionsData();
   } catch (err) {
     throw new Error(getProcessingStoreOpsExceptionMessage(err, dbModule));
   }
 
   const sessionsData: OlmSessions = {};
   for (const persistedSession: OlmPersistSession of dbSessionsData) {
     const { sessionData, version } = persistedSession;
     const session = new olm.Session();
     session.unpickle(picklingKey, sessionData);
     sessionsData[persistedSession.targetDeviceID] = {
       session,
       version,
     };
   }
 
   return sessionsData;
 }
 
 function unpickleInitialCryptoStoreAccount(
   account: PickledOLMAccount,
 ): olm.Account {
   const { picklingKey, pickledAccount } = account;
   const olmAccount = new olm.Account();
   olmAccount.unpickle(picklingKey, pickledAccount);
   return olmAccount;
 }
 
 async function initializeCryptoAccount(
   olmWasmPath: string,
   initialCryptoStore: ?LegacyCryptoStore,
 ) {
   const sqliteQueryExecutor = getSQLiteQueryExecutor();
   if (!sqliteQueryExecutor) {
     throw new Error('Database not initialized');
   }
 
   await olm.init({ locateFile: () => olmWasmPath });
   olmUtility = new olm.Utility();
 
   if (initialCryptoStore) {
     cryptoStore = {
       contentAccountPickleKey: initialCryptoStore.primaryAccount.picklingKey,
       contentAccount: unpickleInitialCryptoStoreAccount(
         initialCryptoStore.primaryAccount,
       ),
       contentSessions: {},
     };
     const notifsCryptoAccount = {
       picklingKey: initialCryptoStore.notificationAccount.picklingKey,
       notificationAccount: unpickleInitialCryptoStoreAccount(
         initialCryptoStore.notificationAccount,
       ),
       synchronizationValue: uuid.v4(),
     };
     await persistCryptoStore(notifsCryptoAccount);
     return;
   }
 
   await olmAPI.initializeCryptoAccount();
 }
 
 async function processAppOlmApiRequest(
   message: WorkerRequestMessage,
 ): Promise<?WorkerResponseMessage> {
   if (message.type === workerRequestMessageTypes.INITIALIZE_CRYPTO_ACCOUNT) {
     await initializeCryptoAccount(
       message.olmWasmPath,
       message.initialCryptoStore,
     );
   } else if (message.type === workerRequestMessageTypes.CALL_OLM_API_METHOD) {
     const method: (...$ReadOnlyArray<mixed>) => mixed = (olmAPI[
       message.method
     ]: any);
     // Flow doesn't allow us to bind the (stringified) method name with
     // the argument types so we need to pass the args as mixed.
     const result = await method(...message.args);
     return {
       type: workerResponseMessageTypes.CALL_OLM_API_METHOD,
       result,
     };
   }
   return undefined;
 }
 
 async function getSignedIdentityKeysBlob(): Promise<SignedIdentityKeysBlob> {
   if (!cryptoStore) {
     throw new Error('Crypto account not initialized');
   }
 
   const { contentAccount } = cryptoStore;
   const { notificationAccount } = await getNotifsCryptoAccount();
 
   const identityKeysBlob: IdentityKeysBlob = {
     notificationIdentityPublicKeys: JSON.parse(
       notificationAccount.identity_keys(),
     ),
     primaryIdentityPublicKeys: JSON.parse(contentAccount.identity_keys()),
   };
 
   const payloadToBeSigned: string = JSON.stringify(identityKeysBlob);
   const signedIdentityKeysBlob: SignedIdentityKeysBlob = {
     payload: payloadToBeSigned,
     signature: contentAccount.sign(payloadToBeSigned),
   };
 
   return signedIdentityKeysBlob;
 }
 
 async function getNewDeviceKeyUpload(): Promise<IdentityNewDeviceKeyUpload> {
   if (!cryptoStore) {
     throw new Error('Crypto account not initialized');
   }
   const { contentAccount } = cryptoStore;
   const [notifsCryptoAccount, signedIdentityKeysBlob] = await Promise.all([
     getNotifsCryptoAccount(),
     getSignedIdentityKeysBlob(),
   ]);
 
   const primaryAccountKeysSet = retrieveAccountKeysSet(contentAccount);
   const notificationAccountKeysSet = retrieveAccountKeysSet(
     notifsCryptoAccount.notificationAccount,
   );
 
   contentAccount.mark_keys_as_published();
   notifsCryptoAccount.notificationAccount.mark_keys_as_published();
 
   await persistCryptoStore(notifsCryptoAccount);
 
   return {
     keyPayload: signedIdentityKeysBlob.payload,
     keyPayloadSignature: signedIdentityKeysBlob.signature,
     contentPrekey: primaryAccountKeysSet.prekey,
     contentPrekeySignature: primaryAccountKeysSet.prekeySignature,
     notifPrekey: notificationAccountKeysSet.prekey,
     notifPrekeySignature: notificationAccountKeysSet.prekeySignature,
     contentOneTimeKeys: primaryAccountKeysSet.oneTimeKeys,
     notifOneTimeKeys: notificationAccountKeysSet.oneTimeKeys,
   };
 }
 
 async function getExistingDeviceKeyUpload(): Promise<IdentityExistingDeviceKeyUpload> {
   if (!cryptoStore) {
     throw new Error('Crypto account not initialized');
   }
   const { contentAccount } = cryptoStore;
   const [notifsCryptoAccount, signedIdentityKeysBlob] = await Promise.all([
     getNotifsCryptoAccount(),
     getSignedIdentityKeysBlob(),
   ]);
 
   const { prekey: contentPrekey, prekeySignature: contentPrekeySignature } =
     retrieveIdentityKeysAndPrekeys(contentAccount);
   const { prekey: notifPrekey, prekeySignature: notifPrekeySignature } =
     retrieveIdentityKeysAndPrekeys(notifsCryptoAccount.notificationAccount);
 
   await persistCryptoStore(notifsCryptoAccount);
 
   return {
     keyPayload: signedIdentityKeysBlob.payload,
     keyPayloadSignature: signedIdentityKeysBlob.signature,
     contentPrekey,
     contentPrekeySignature,
     notifPrekey,
     notifPrekeySignature,
   };
 }
 
 function getNotifsPersistenceKeys(
   cookie: ?string,
   keyserverID: string,
   platformDetails: PlatformDetails,
 ) {
   if (hasMinCodeVersion(platformDetails, { majorDesktop: 12 })) {
     return {
       notifsOlmDataEncryptionKeyDBLabel: getOlmEncryptionKeyDBLabelForCookie(
         cookie,
         keyserverID,
       ),
       notifsOlmDataContentKey: getOlmDataKeyForCookie(cookie, keyserverID),
     };
   } else {
     return {
       notifsOlmDataEncryptionKeyDBLabel:
         getOlmEncryptionKeyDBLabelForCookie(cookie),
       notifsOlmDataContentKey: getOlmDataKeyForCookie(cookie),
     };
   }
 }
 
 async function reassignLocalForageItem(source: string, destination: string) {
   const value = await localforage.getItem<mixed>(source);
   if (!value) {
     return;
   }
   const valueAtDestination = await localforage.getItem<mixed>(destination);
   if (!valueAtDestination) {
     await localforage.setItem(destination, value);
   }
   await localforage.removeItem(source);
 }
 
 const olmAPI: OlmAPI = {
   async initializeCryptoAccount(): Promise<void> {
     const sqliteQueryExecutor = getSQLiteQueryExecutor();
     if (!sqliteQueryExecutor) {
       throw new Error('Database not initialized');
     }
 
     const [contentAccountResult, notificationAccountResult] = await Promise.all(
       [
         getOrCreateOlmAccount(sqliteQueryExecutor.getContentAccountID()),
         getOrCreateOlmAccount(sqliteQueryExecutor.getNotifsAccountID()),
       ],
     );
 
     const contentSessions = getOlmSessions(contentAccountResult.picklingKey);
 
     cryptoStore = {
       contentAccountPickleKey: contentAccountResult.picklingKey,
       contentAccount: contentAccountResult.account,
       contentSessions,
     };
     const notifsCryptoAccount = {
       picklingKey: notificationAccountResult.picklingKey,
       notificationAccount: notificationAccountResult.account,
       synchronizationValue: notificationAccountResult.synchronizationValue,
     };
 
     await persistCryptoStore(notifsCryptoAccount);
   },
   async getUserPublicKey(): Promise<ClientPublicKeys> {
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
     const { contentAccount } = cryptoStore;
     const [{ notificationAccount }, { payload, signature }] = await Promise.all(
       [getNotifsCryptoAccount(), getSignedIdentityKeysBlob()],
     );
 
     return {
       primaryIdentityPublicKeys: JSON.parse(contentAccount.identity_keys()),
       notificationIdentityPublicKeys: JSON.parse(
         notificationAccount.identity_keys(),
       ),
       blobPayload: payload,
       signature,
     };
   },
   async encrypt(content: string, deviceID: string): Promise<EncryptedData> {
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
     const olmSession = cryptoStore.contentSessions[deviceID];
     if (!olmSession) {
-      throw new Error(`No session for deviceID: ${deviceID}`);
+      throw new Error(olmSessionErrors.sessionDoesNotExists);
     }
     const encryptedContent = olmSession.session.encrypt(content);
 
     await persistCryptoStore();
 
     return {
       message: encryptedContent.body,
       messageType: encryptedContent.type,
     };
   },
   async encryptAndPersist(
     content: string,
     deviceID: string,
     messageID: string,
   ): Promise<EncryptedData> {
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
     const olmSession = cryptoStore.contentSessions[deviceID];
     if (!olmSession) {
-      throw new Error(`No session for deviceID: ${deviceID}`);
+      throw new Error(olmSessionErrors.sessionDoesNotExists);
     }
 
     const encryptedContent = olmSession.session.encrypt(content);
 
     const sqliteQueryExecutor = getSQLiteQueryExecutor();
     const dbModule = getDBModule();
     if (!sqliteQueryExecutor || !dbModule) {
       throw new Error(
         "Couldn't persist crypto store because database is not initialized",
       );
     }
 
     const result: EncryptedData = {
       message: encryptedContent.body,
       messageType: encryptedContent.type,
     };
 
     sqliteQueryExecutor.beginTransaction();
     try {
       sqliteQueryExecutor.setCiphertextForOutboundP2PMessage(
         messageID,
         deviceID,
         JSON.stringify(result),
       );
       await persistCryptoStore(undefined, true);
       sqliteQueryExecutor.commitTransaction();
     } catch (e) {
       sqliteQueryExecutor.rollbackTransaction();
       throw e;
     }
 
     return result;
   },
   async encryptNotification(
     payload: string,
     deviceID: string,
   ): Promise<EncryptedData> {
     const { body: message, type: messageType } = await encryptNotification(
       payload,
       deviceID,
     );
     return { message, messageType };
   },
   async decrypt(
     encryptedData: EncryptedData,
     deviceID: string,
   ): Promise<string> {
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
 
     const olmSession = cryptoStore.contentSessions[deviceID];
     if (!olmSession) {
-      throw new Error(`No session for deviceID: ${deviceID}`);
+      throw new Error(olmSessionErrors.sessionDoesNotExists);
     }
 
     const result = olmSession.session.decrypt(
       encryptedData.messageType,
       encryptedData.message,
     );
 
     await persistCryptoStore();
 
     return result;
   },
   async decryptAndPersist(
     encryptedData: EncryptedData,
     deviceID: string,
     messageID: string,
   ): Promise<string> {
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
 
     const olmSession = cryptoStore.contentSessions[deviceID];
     if (!olmSession) {
-      throw new Error(`No session for deviceID: ${deviceID}`);
+      throw new Error(olmSessionErrors.sessionDoesNotExists);
     }
 
     const result = olmSession.session.decrypt(
       encryptedData.messageType,
       encryptedData.message,
     );
 
     const sqliteQueryExecutor = getSQLiteQueryExecutor();
     const dbModule = getDBModule();
     if (!sqliteQueryExecutor || !dbModule) {
       throw new Error(
         "Couldn't persist crypto store because database is not initialized",
       );
     }
 
     const receivedMessage: InboundP2PMessage = {
       messageID,
       senderDeviceID: deviceID,
       plaintext: result,
       status: 'decrypted',
     };
 
     sqliteQueryExecutor.beginTransaction();
     try {
       sqliteQueryExecutor.addInboundP2PMessage(receivedMessage);
       await persistCryptoStore(undefined, true);
       sqliteQueryExecutor.commitTransaction();
     } catch (e) {
       sqliteQueryExecutor.rollbackTransaction();
       throw e;
     }
 
     return result;
   },
   async contentInboundSessionCreator(
     contentIdentityKeys: OLMIdentityKeys,
     initialEncryptedData: EncryptedData,
     sessionVersion: number,
     overwrite: boolean,
   ): Promise<string> {
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
     const { contentAccount, contentSessions } = cryptoStore;
 
     const existingSession = contentSessions[contentIdentityKeys.ed25519];
     if (existingSession) {
       if (!overwrite && existingSession.version > sessionVersion) {
         throw new Error(olmSessionErrors.alreadyCreated);
       } else if (!overwrite && existingSession.version === sessionVersion) {
         throw new Error(olmSessionErrors.raceCondition);
       }
     }
 
     const session = new olm.Session();
     session.create_inbound_from(
       contentAccount,
       contentIdentityKeys.curve25519,
       initialEncryptedData.message,
     );
 
     contentAccount.remove_one_time_keys(session);
     const initialEncryptedMessage = session.decrypt(
       initialEncryptedData.messageType,
       initialEncryptedData.message,
     );
 
     contentSessions[contentIdentityKeys.ed25519] = {
       session,
       version: sessionVersion,
     };
     await persistCryptoStore();
 
     return initialEncryptedMessage;
   },
   async contentOutboundSessionCreator(
     contentIdentityKeys: OLMIdentityKeys,
     contentInitializationInfo: OlmSessionInitializationInfo,
   ): Promise<OutboundSessionCreationResult> {
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
     const { contentAccount, contentSessions } = cryptoStore;
     const existingSession = contentSessions[contentIdentityKeys.ed25519];
 
     const session = new olm.Session();
     if (contentInitializationInfo.oneTimeKey) {
       session.create_outbound(
         contentAccount,
         contentIdentityKeys.curve25519,
         contentIdentityKeys.ed25519,
         contentInitializationInfo.prekey,
         contentInitializationInfo.prekeySignature,
         contentInitializationInfo.oneTimeKey,
       );
     } else {
       session.create_outbound_without_otk(
         contentAccount,
         contentIdentityKeys.curve25519,
         contentIdentityKeys.ed25519,
         contentInitializationInfo.prekey,
         contentInitializationInfo.prekeySignature,
       );
     }
     const initialEncryptedData = session.encrypt(
       JSON.stringify(initialEncryptedMessageContent),
     );
 
     const newSessionVersion = existingSession ? existingSession.version + 1 : 1;
     contentSessions[contentIdentityKeys.ed25519] = {
       session,
       version: newSessionVersion,
     };
     await persistCryptoStore();
 
     const encryptedData: EncryptedData = {
       message: initialEncryptedData.body,
       messageType: initialEncryptedData.type,
     };
 
     return { encryptedData, sessionVersion: newSessionVersion };
   },
   async isContentSessionInitialized(deviceID: string) {
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
     return !!cryptoStore.contentSessions[deviceID];
   },
   async notificationsOutboundSessionCreator(
     deviceID: string,
     notificationsIdentityKeys: OLMIdentityKeys,
     notificationsInitializationInfo: OlmSessionInitializationInfo,
   ): Promise<EncryptedData> {
     const dataPersistenceKey = getOlmDataKeyForDeviceID(deviceID);
     const dataEncryptionKeyDBLabel =
       getOlmEncryptionKeyDBLabelForDeviceID(deviceID);
 
     return createAndPersistNotificationsOutboundSession(
       notificationsIdentityKeys,
       notificationsInitializationInfo,
       dataPersistenceKey,
       dataEncryptionKeyDBLabel,
     );
   },
   async isDeviceNotificationsSessionInitialized(deviceID: string) {
     const dataPersistenceKey = getOlmDataKeyForDeviceID(deviceID);
     const dataEncryptionKeyDBLabel =
       getOlmEncryptionKeyDBLabelForDeviceID(deviceID);
 
     const allKeys = await localforage.keys();
     const allKeysSet = new Set(allKeys);
     return (
       allKeysSet.has(dataPersistenceKey) &&
       allKeysSet.has(dataEncryptionKeyDBLabel)
     );
   },
   async isNotificationsSessionInitializedWithDevices(
     deviceIDs: $ReadOnlyArray<string>,
   ) {
     const allKeys = await localforage.keys();
     const allKeysSet = new Set(allKeys);
 
     const deviceInfoPairs = deviceIDs.map(deviceID => {
       const dataPersistenceKey = getOlmDataKeyForDeviceID(deviceID);
       const dataEncryptionKeyDBLabel =
         getOlmEncryptionKeyDBLabelForDeviceID(deviceID);
       return [
         deviceID,
         allKeysSet.has(dataPersistenceKey) &&
           allKeysSet.has(dataEncryptionKeyDBLabel),
       ];
     });
 
     return Object.fromEntries(deviceInfoPairs);
   },
   async keyserverNotificationsSessionCreator(
     cookie: ?string,
     notificationsIdentityKeys: OLMIdentityKeys,
     notificationsInitializationInfo: OlmSessionInitializationInfo,
     keyserverID: string,
   ): Promise<string> {
     const platformDetails = getPlatformDetails();
     if (!platformDetails) {
       throw new Error('Worker not initialized');
     }
 
     const { notifsOlmDataContentKey, notifsOlmDataEncryptionKeyDBLabel } =
       getNotifsPersistenceKeys(cookie, keyserverID, platformDetails);
 
     const { message } = await createAndPersistNotificationsOutboundSession(
       notificationsIdentityKeys,
       notificationsInitializationInfo,
       notifsOlmDataContentKey,
       notifsOlmDataEncryptionKeyDBLabel,
     );
 
     return message;
   },
   async reassignNotificationsSession(
     prevCookie: ?string,
     newCookie: ?string,
     keyserverID: string,
   ): Promise<void> {
     const platformDetails = getPlatformDetails();
     if (!platformDetails) {
       throw new Error('Worker not initialized');
     }
 
     const prevPersistenceKeys = getNotifsPersistenceKeys(
       prevCookie,
       keyserverID,
       platformDetails,
     );
 
     const newPersistenceKeys = getNotifsPersistenceKeys(
       newCookie,
       keyserverID,
       platformDetails,
     );
 
     await Promise.all([
       reassignLocalForageItem(
         prevPersistenceKeys.notifsOlmDataContentKey,
         newPersistenceKeys.notifsOlmDataContentKey,
       ),
       reassignLocalForageItem(
         prevPersistenceKeys.notifsOlmDataEncryptionKeyDBLabel,
         newPersistenceKeys.notifsOlmDataEncryptionKeyDBLabel,
       ),
     ]);
   },
   async getOneTimeKeys(numberOfKeys: number): Promise<OneTimeKeysResultValues> {
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
     const { contentAccount } = cryptoStore;
     const notifsCryptoAccount = await getNotifsCryptoAccount();
 
     const contentOneTimeKeys = getAccountOneTimeKeys(
       contentAccount,
       numberOfKeys,
     );
     contentAccount.mark_keys_as_published();
 
     const notificationsOneTimeKeys = getAccountOneTimeKeys(
       notifsCryptoAccount.notificationAccount,
       numberOfKeys,
     );
     notifsCryptoAccount.notificationAccount.mark_keys_as_published();
 
     await persistCryptoStore(notifsCryptoAccount);
 
     return { contentOneTimeKeys, notificationsOneTimeKeys };
   },
   async validateAndUploadPrekeys(authMetadata): Promise<void> {
     const { userID, deviceID, accessToken } = authMetadata;
     if (!userID || !deviceID || !accessToken) {
       return;
     }
     const identityClient = getIdentityClient();
 
     if (!identityClient) {
       throw new Error('Identity client not initialized');
     }
 
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
     const { contentAccount } = cryptoStore;
     const notifsCryptoAccount = await getNotifsCryptoAccount();
 
     // Content and notification accounts' keys are always rotated at the same
     // time so we only need to check one of them.
     if (shouldRotatePrekey(contentAccount)) {
       contentAccount.generate_prekey();
       notifsCryptoAccount.notificationAccount.generate_prekey();
     }
     if (shouldForgetPrekey(contentAccount)) {
       contentAccount.forget_old_prekey();
       notifsCryptoAccount.notificationAccount.forget_old_prekey();
     }
     await persistCryptoStore(notifsCryptoAccount);
 
     if (!contentAccount.unpublished_prekey()) {
       return;
     }
 
     const { prekey: notifPrekey, prekeySignature: notifPrekeySignature } =
       getAccountPrekeysSet(notifsCryptoAccount.notificationAccount);
     const { prekey: contentPrekey, prekeySignature: contentPrekeySignature } =
       getAccountPrekeysSet(contentAccount);
 
     if (!notifPrekeySignature || !contentPrekeySignature) {
       throw new Error('Prekey signature is missing');
     }
 
     await identityClient.publishWebPrekeys({
       contentPrekey,
       contentPrekeySignature,
       notifPrekey,
       notifPrekeySignature,
     });
     contentAccount.mark_prekey_as_published();
     notifsCryptoAccount.notificationAccount.mark_prekey_as_published();
 
     await persistCryptoStore(notifsCryptoAccount);
   },
   async signMessage(message: string): Promise<string> {
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
     const { contentAccount } = cryptoStore;
     return contentAccount.sign(message);
   },
   async verifyMessage(
     message: string,
     signature: string,
     signingPublicKey: string,
   ): Promise<boolean> {
     if (!olmUtility) {
       throw new Error('Crypto account not initialized');
     }
     try {
       olmUtility.ed25519_verify(signingPublicKey, message, signature);
       return true;
     } catch (err) {
       const isSignatureInvalid =
         getMessageForException(err)?.includes('BAD_MESSAGE_MAC');
       if (isSignatureInvalid) {
         return false;
       }
       throw err;
     }
   },
   async markPrekeysAsPublished(): Promise<void> {
     if (!cryptoStore) {
       throw new Error('Crypto account not initialized');
     }
     const { contentAccount } = cryptoStore;
     const notifsCryptoAccount = await getNotifsCryptoAccount();
 
     contentAccount.mark_prekey_as_published();
     notifsCryptoAccount.notificationAccount.mark_prekey_as_published();
 
     await persistCryptoStore(notifsCryptoAccount);
   },
 };
 
 export {
   clearCryptoStore,
   processAppOlmApiRequest,
   getSignedIdentityKeysBlob,
   getNewDeviceKeyUpload,
   getExistingDeviceKeyUpload,
 };