sdk_client/src/websockets.ts

import Services from "./services";
import { AnkFlag, AnkNetworkMsg, CachedMessage } from "../dist/pkg/sdk_client";

class WebSocketClient {
    private ws: WebSocket;
    private messageQueue: string[] = [];

    constructor(url: string, private services: Services) {
        this.ws = new WebSocket(url);

        this.ws.addEventListener('open', (event) => {
            console.log('WebSocket connection established');
            // Once the connection is open, send all messages in the queue
            while (this.messageQueue.length > 0) {
                const message = this.messageQueue.shift();
                if (message) {
                    this.ws.send(message);
                }
            }
        });

        // Listen for messages
        this.ws.addEventListener('message', (event) => {
            const msgData = event.data;

            (async () => {
                if (typeof(msgData) === 'string') {
                    console.log("Received text message: "+msgData);
                    try {
                        const feeRate = 1;
                        // By parsing the message, we can link it with existing cached message and return the updated version of the message
                        let res: CachedMessage = await services.parseNetworkMessage(msgData, feeRate);
                        console.debug(res);
                        if (res.status === 'FaucetComplete') { 
                            // we received a faucet tx, there's nothing else to do
                            window.alert(`New faucet output\n${res.commited_in}`);
                            await services.updateMessages(res);
                            await services.updateOwnedOutputsForUser();
                        } else if (res.status === 'TxWaitingCipher') {
                            // we received a tx but we don't have the cipher
                            console.debug(`received notification in output ${res.commited_in}, waiting for cipher message`);
                            await services.updateMessages(res);
                            await services.updateOwnedOutputsForUser();
                        } else if (res.status === 'CipherWaitingTx') {
                            // we received a cipher but we don't have the key
                            console.debug(`received a cipher`); 
                            await services.updateMessages(res);
                        } else if (res.status === 'SentWaitingConfirmation') {
                            // We are sender and we're waiting for the challenge that will confirm recipient got the transaction and the message
                            await services.updateMessages(res);
                            await services.updateOwnedOutputsForUser();
                        } else if (res.status === 'MustSpendConfirmation') {
                            // we received a challenge for a notification we made
                            // that means we can stop rebroadcasting the tx and we must spend the challenge to confirm
                            window.alert(`Spending ${res.confirmed_by} to prove our identity`);
                            console.debug(`sending confirm message to ${res.recipient}`);
                            await services.updateMessages(res);
                            await services.answer_confirmation_message(res);
                        } else if (res.status === 'ReceivedMustConfirm') {
                            // we found a notification and decrypted the cipher
                            window.alert(`Received message from ${res.sender}\n${res.plaintext}`);
                            // we must spend the commited_in output to sender
                            await services.updateMessages(res);
                            await services.confirm_sender_address(res);
                        } else if (res.status === 'Complete') {
                            window.alert(`Received confirmation that ${res.sender} is the author of message ${res.plaintext}`)
                            await services.updateMessages(res);
                            await services.updateOwnedOutputsForUser();
                        } else {
                            console.debug('Received an unimplemented valid message');
                        }
                    } catch (error) {
                        console.error('Received an invalid message:', error);
                    }
                } else {
                    console.error('Received a non-string message');
                }
            })();
        });

        // Listen for possible errors
        this.ws.addEventListener('error', (event) => {
            console.error('WebSocket error:', event);
        });

        // Listen for when the connection is closed
        this.ws.addEventListener('close', (event) => {
            console.log('WebSocket is closed now.');
        });
    }

    // Method to send messages
    public sendMessage(flag: AnkFlag, message: string): void {
        if (this.ws.readyState === WebSocket.OPEN) {
            const networkMessage: AnkNetworkMsg = {
                'flag': flag,
                'content': message
            }
            // console.debug("Sending message:", JSON.stringify(networkMessage));
            this.ws.send(JSON.stringify(networkMessage));
        } else {
            console.warn('WebSocket is not open. ReadyState:', this.ws.readyState);
            this.messageQueue.push(message);
        }
    }

    public getUrl(): string {
        return this.ws.url;
    }

    // Method to close the WebSocket connection
    public close(): void {
        this.ws.close();
    }
}

export { WebSocketClient };