13
0
livetrax/share/web_surfaces/shared/channel.js

79 lines
2.2 KiB
JavaScript

/*
* Copyright © 2020 Luciano Iam <lucianito@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
const JSON_INF = 1.0e+128;
export class ArdourMessageChannel {
constructor (host) {
// https://developer.mozilla.org/en-US/docs/Web/API/URL/host
this.host = host;
}
open () {
return new Promise((resolve, reject) => {
this.socket = new WebSocket(`ws://${this.host}`);
this.socket.onclose = () => this.closeCallback();
this.socket.onerror = (error) => this.errorCallback(error);
this.socket.onmessage = (event) => this._onMessage(event);
this.socket.onopen = resolve;
});
}
closeCallback () {
// empty
}
errorCallback (error) {
// empty
}
messageCallback (node, addr, val) {
// empty
}
send (node, addr, val) {
for (const i in val) {
if (val[i] == Infinity) {
val[i] = JSON_INF;
} else if (val[i] == -Infinity) {
val[i] = -JSON_INF;
}
}
const json = JSON.stringify({node: node, addr: addr, val: val});
this.socket.send(json);
}
_onMessage (event) {
const msg = JSON.parse(event.data);
for (const i in msg.val) {
if (msg.val[i] >= JSON_INF) {
msg.val[i] = Infinity;
} else if (msg.val[i] <= -JSON_INF) {
msg.val[i] = -Infinity;
}
}
this.messageCallback(msg.node, msg.addr || [], msg.val);
}
}