js-waku/examples/eth-pm/src/waku.ts

import { Dispatch, SetStateAction } from 'react';
import { Waku, WakuMessage } from 'js-waku';
import { PrivateMessage, PublicKeyMessage } from './messaging/wire';
import { validatePublicKeyMessage } from './crypto';
import { Message } from './messaging/Messages';
import { bufToHex, equalByteArrays } from 'js-waku/lib/utils';

export const PublicKeyContentTopic = '/eth-pm/1/public-key/proto';
export const PrivateMessageContentTopic = '/eth-pm/1/private-message/proto';

export async function initWaku(): Promise<Waku> {
  const waku = await Waku.create({ bootstrap: true });

  // Wait to be connected to at least one peer
  await new Promise((resolve, reject) => {
    // If we are not connected to any peer within 10sec let's just reject
    // As we are not implementing connection management in this example

    setTimeout(reject, 10000);
    waku.libp2p.connectionManager.on('peer:connect', () => {
      resolve(null);
    });
  });

  return waku;
}

export function handlePublicKeyMessage(
  myAddress: string | undefined,
  setter: Dispatch<SetStateAction<Map<string, Uint8Array>>>,
  msg: WakuMessage
) {
  console.log('Public Key Message received:', msg);
  if (!msg.payload) return;
  const publicKeyMsg = PublicKeyMessage.decode(msg.payload);
  if (!publicKeyMsg) return;
  if (myAddress && equalByteArrays(publicKeyMsg.ethAddress, myAddress)) return;

  const res = validatePublicKeyMessage(publicKeyMsg);
  console.log('Is Public Key Message valid?', res);

  if (res) {
    setter((prevPks: Map<string, Uint8Array>) => {
      prevPks.set(
        bufToHex(publicKeyMsg.ethAddress),
        publicKeyMsg.encryptionPublicKey
      );
      return new Map(prevPks);
    });
  }
}

export async function handlePrivateMessage(
  setter: Dispatch<SetStateAction<Message[]>>,
  address: string,
  wakuMsg: WakuMessage
) {
  console.log('Private Message received:', wakuMsg);
  if (!wakuMsg.payload) return;
  const privateMessage = PrivateMessage.decode(wakuMsg.payload);
  if (!privateMessage) {
    console.log('Failed to decode Private Message');
    return;
  }
  if (!equalByteArrays(privateMessage.toAddress, address)) return;

  const timestamp = wakuMsg.timestamp ? wakuMsg.timestamp : new Date();

  console.log('Message decrypted:', privateMessage.message);
  setter((prevMsgs: Message[]) => {
    const copy = prevMsgs.slice();
    copy.push({
      text: privateMessage.message,
      timestamp: timestamp,
    });
    return copy;
  });
}