Initial Live Share support

src/services/liveShare.ts

@@ -0,0 +1,45 @@
+import * as vscode from "vscode";
+import * as vsls from "vsls";
+import Config from "./config";
+
+export async function initialize(
+    context: vscode.ExtensionContext,
+    config: Config,
+    activateProfileHandler: (profile: string) => void
+) {
+    const liveShare = await vsls.getApi();
+    if (!liveShare) {
+        return;
+    }
+
+    const liveShareProfile = config.getLiveShareProfile();
+    if (!liveShareProfile) {
+        return;
+    }
+
+    // Check to see whether there was a lingering profile set
+    // (e.g. because the user closed VS Code while in a Live Share
+    // session), and if so, restore the right profile.
+    restorePreviousProfile(config, activateProfileHandler);
+
+    liveShare.onDidChangeSession(e => {
+        if (e.session.id) {
+            activateProfileHandler(liveShareProfile);
+        } else {
+            restorePreviousProfile(config, activateProfileHandler);
+        }
+    })
+}
+
+function restorePreviousProfile(
+    config: Config,
+    activateProfileHandler: (profile: string) => void
+) {
+    const previousProfile = config.getPreviousProfile();
+    if (!previousProfile) {
+        return;
+    }
+
+    config.setPreviousProfile(undefined);
+    activateProfileHandler(previousProfile);
+}