feat: add "multi file auth state" implementation

1. add multi file auth state since it's far more efficient than single state
2. deprecate single file auth state (please don't use it anymore)

src/Utils/auth-utils.ts

@@ -1,10 +1,9 @@
 import { Boom } from '@hapi/boom'
 import { randomBytes } from 'crypto'
 import type { Logger } from 'pino'
-import { proto } from '../../WAProto'
-import type { AuthenticationCreds, AuthenticationState, SignalDataSet, SignalDataTypeMap, SignalKeyStore, SignalKeyStoreWithTransaction, TransactionCapabilityOptions } from '../Types'
+import type { AuthenticationCreds, SignalDataSet, SignalDataTypeMap, SignalKeyStore, SignalKeyStoreWithTransaction, TransactionCapabilityOptions } from '../Types'
 import { Curve, signedKeyPair } from './crypto'
-import { BufferJSON, delay, generateRegistrationId } from './generics'
+import { delay, generateRegistrationId } from './generics'
 
 /**
  * Adds DB like transaction capability (https://en.wikipedia.org/wiki/Database_transaction) to the SignalKeyStore,
@@ -126,79 +125,4 @@ export const initAuthCreds = (): AuthenticationCreds => {
 			unarchiveChats: false
 		}
 	}
-}
-
-// useless key map only there to maintain backwards compatibility
-// do not use in your own systems please
-const KEY_MAP: { [T in keyof SignalDataTypeMap]: string } = {
-	'pre-key': 'preKeys',
-	'session': 'sessions',
-	'sender-key': 'senderKeys',
-	'app-state-sync-key': 'appStateSyncKeys',
-	'app-state-sync-version': 'appStateVersions',
-	'sender-key-memory': 'senderKeyMemory'
-}
-/** stores the full authentication state in a single JSON file */
-export const useSingleFileAuthState = (filename: string, logger?: Logger): { state: AuthenticationState, saveState: () => void } => {
-	// require fs here so that in case "fs" is not available -- the app does not crash
-	const { readFileSync, writeFileSync, existsSync } = require('fs')
-	let creds: AuthenticationCreds
-	let keys: any = { }
-
-	// save the authentication state to a file
-	const saveState = () => {
-		logger && logger.trace('saving auth state')
-		writeFileSync(
-			filename,
-			// BufferJSON replacer utility saves buffers nicely
-			JSON.stringify({ creds, keys }, BufferJSON.replacer, 2)
-		)
-	}
-
-	if(existsSync(filename)) {
-		const result = JSON.parse(
-			readFileSync(filename, { encoding: 'utf-8' }),
-			BufferJSON.reviver
-		)
-		creds = result.creds
-		keys = result.keys
-	} else {
-		creds = initAuthCreds()
-		keys = { }
-	}
-
-	return {
-		state: {
-			creds,
-			keys: {
-				get: (type, ids) => {
-					const key = KEY_MAP[type]
-					return ids.reduce(
-						(dict, id) => {
-							let value = keys[key]?.[id]
-							if(value) {
-								if(type === 'app-state-sync-key') {
-									value = proto.AppStateSyncKeyData.fromObject(value)
-								}
-
-								dict[id] = value
-							}
-
-							return dict
-						}, { }
-					)
-				},
-				set: (data) => {
-					for(const _key in data) {
-						const key = KEY_MAP[_key as keyof SignalDataTypeMap]
-						keys[key] = keys[key] || { }
-						Object.assign(keys[key], data[_key])
-					}
-
-					saveState()
-				}
-			}
-		},
-		saveState
-	}
 }