Add xterm itegration

* Move to TypeScript from legacy JavaScript
* Add support of xterm.js
* Hterm is still available for backward compatibility

js/src/main.ts

@@ -0,0 +1,30 @@
+import { TermHterm } from "./hterm";
+import { TermXterm } from "./xterm";
+import { Terminal, WebTTY, protocols } from "./webtty";
+import { ConnectionFactory } from "./websocket";
+
+// @TODO remove these
+declare var gotty_auth_token: string;
+declare var gotty_term: string;
+
+const elem = document.getElementById("terminal")
+
+if (elem !== null) {
+    var term: Terminal;
+    if (gotty_term == "hterm") {
+        term = new TermHterm(elem);
+    } else {
+        term = new TermXterm(elem);
+    }
+    const httpsEnabled = window.location.protocol == "https:";
+    const url = (httpsEnabled ? 'wss://' : 'ws://') + window.location.host + window.location.pathname + 'ws';
+    const args = window.location.search;
+    const factory = new ConnectionFactory(url, protocols);
+    const wt = new WebTTY(term, factory, args, gotty_auth_token);
+    const closer = wt.open();
+
+    window.addEventListener("unload", () => {
+        closer();
+        term.close();
+    });
+};