Added requestPairingCode method and handler

Fixed typo (trimUndefineds)
Added bytesToCrockford
Replaced advSecretKey with advKeyPair
Added pairingCode prop
Fixed formatting
Added pairing code example

src/Utils/generics.ts

@@ -379,7 +379,7 @@ export const isWABusinessPlatform = (platform: string) => {
 	return platform === 'smbi' || platform === 'smba'
 }
 
-export function trimUndefineds(obj: any) {
+export function trimUndefined(obj: any) {
 	for(const key in obj) {
 		if(typeof obj[key] === 'undefined') {
 			delete obj[key]
@@ -388,3 +388,54 @@ export function trimUndefineds(obj: any) {
 
 	return obj
 }
+
+const CROCKFORD_CHARACTERS = '123456789ABCDEFGHJKLMNPQRSTVWXYZ'
+
+export function bytesToCrockford(buffer: Buffer): string {
+	let value = 0
+	let bitCount = 0
+	const crockford: string[] = []
+
+	for(let i = 0; i < buffer.length; i++) {
+		value = (value << 8) | (buffer[i] & 0xff)
+		bitCount += 8
+
+		while(bitCount >= 5) {
+			crockford.push(CROCKFORD_CHARACTERS.charAt((value >>> (bitCount - 5)) & 31))
+			bitCount -= 5
+		}
+	}
+
+	if(bitCount > 0) {
+		crockford.push(CROCKFORD_CHARACTERS.charAt((value << (5 - bitCount)) & 31))
+	}
+
+	return crockford.join('')
+}
+
+export async function derivePairingKey(pairingCode: string, salt: Buffer) {
+	const encoded = new TextEncoder().encode(pairingCode)
+	const cryptoKey = await crypto.subtle.importKey(
+		'raw',
+		encoded,
+		{
+			name: 'PBKDF2'
+		},
+		!1,
+		[
+			'deriveKey'
+		]
+	)
+	return await crypto.subtle.deriveKey({
+		name: 'PBKDF2',
+		hash: 'SHA-256',
+		salt: salt,
+		iterations: 2 << 16
+	}, cryptoKey, {
+		name: 'AES-CTR',
+		length: 256
+	}, false, [
+		'encrypt',
+		'decrypt'
+	])
+}