skald/static/example/example.js

/* Skald client example - audio-only. */

/**
 * The main function.
 *
 * @param {string} url
 */
async function start(url) {
    // fetch the hall information
    let r = await fetch(url + ".status");
    if(!r.ok) {
        throw new Error(`${r.status} ${r.statusText}`);
    }
    let status = await r.json();

    // parse a token in the URL.
    let token = null;
    let parms = new URLSearchParams(window.location.search);
    if(parms.has('token'))
        token = parms.get('token');

    // connect to the server
    if(token) {
        serverConnect(status, token);
    } else if(status.authPortal) {
        window.location.href = status.authPortal
        return;
    } else {
        serverConnect(status, null);
    }
}

/**
 * Display the connection status.
 *
 * @param {string} status
 */
function displayStatus(status) {
    let c = document.getElementById('status');
    c.textContent = status;
}

/**
 * Connect to the server.
 *
 * @param {Object} status
 * @param {string} token
 */
function serverConnect(status, token) {
    let conn = new ServerConnection();
    conn.onconnected = async function() {
        displayStatus('Connected');
        let creds = token ?
            {type: 'token', token: token} :
            {type: 'password', password: ''};
        await this.join("public", "example-user", creds);
    };
    conn.onchat = onChat;
    conn.onusermessage = onUserMessage;
    conn.onclose = function() {
        displayStatus('Disconnected');
    }
    conn.onjoined = onJoined;
    conn.connect(status.endpoint);
}

/**
 * Called whenever we receive a chat message.
 */
function onChat(id, dest, username, time, privileged, history, kind, message) {
    let p = document.createElement('p');
    p.textContent = `${username}${dest ? ' → ' + dest : ''}: ${message}`;
    let container = document.getElementById('chat');
    container.appendChild(p);
}

/**
 * Called whenever we receive a user message.
 */
function onUserMessage(id, dest, username, time, privileged, kind, error, message) {
    switch(kind) {
    case 'kicked':
    case 'error':
    case 'warning':
    case 'info':
        if(!privileged) {
            console.error(`Got unprivileged message of kind ${kind}`);
            return;
        }
        displayError(message);
        break;
    case 'clearchat':
        if(!privileged) {
            console.error(`Got unprivileged message of kind ${kind}`);
            return;
        }
        document.getElementById('chat').textContent = '';
        break;
    }
}

/**
 * Called when we join or leave a hall.
 */
async function onJoined(kind, hall, perms, status, data, error, message) {
    switch(kind) {
    case 'fail':
        displayError(message);
        this.close();
        break;
    case 'redirect':
        this.close();
        document.location.href = message;
        return;
    case 'leave':
        displayStatus('Connected');
        this.close();
        break;
    case 'join':
    case 'change':
        displayStatus(`Connected as ${this.username} in hall ${this.hall}.`);
        // request audio from the server
        this.request({'': ['audio']});
        break;
    default:
        displayError(`Unexpected state ${kind}.`);
        this.close();
        break;
    }
}

/**
 * Display an error message.
 *
 * @param {string} message
 */
function displayError(message) {
    document.getElementById('error').textContent = message;
}

document.getElementById('start').onclick = async function(e) {
    let button = /** @type{HTMLButtonElement} */(this);
    button.hidden = true;
    try {
        await start("/hall/public/");
    } catch(e) {
        displayError(e);
    };
}