Pre-phrase signal (#10)

* Touch file hat snapshots

* Add support for signals

Author: pokey

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2021 Brandon Virgil Rule
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

src/extension.ts

@@ -2,6 +2,7 @@ import * as vscode from "vscode";
 
 import { initializeCommunicationDir } from "./initializeCommunicationDir";
 import CommandRunner from "./commandRunner";
+import { getInboundSignal } from "./signal";
 
 export function activate(context: vscode.ExtensionContext) {
   initializeCommunicationDir();
@@ -14,6 +15,20 @@ export function activate(context: vscode.ExtensionContext) {
       commandRunner.runCommand
     )
   );
+
+  return {
+    /**
+     * These signals can be used as a form of IPC to indicate that an event has
+     * occurred.
+     */
+    signals: {
+      /**
+       * This signal is emitted by the voice engine to indicate that a phrase has
+       * just begun execution.
+       */
+      prePhrase: getInboundSignal("prePhrase"),
+    },
+  };
 }
 
 // this method is called when your extension is deactivated

src/paths.ts

@@ -11,6 +11,10 @@ export function getCommunicationDirPath() {
   return join(tmpdir(), `vscode-command-server${suffix}`);
 }
 
+export function getSignalDirPath(): string {
+  return join(getCommunicationDirPath(), "signals");
+}
+
 export function getRequestPath() {
   return join(getCommunicationDirPath(), "request.json");
 }

src/signal.ts

@@ -0,0 +1,33 @@
+import { stat } from "fs/promises";
+import { join } from "path";
+import { getSignalDirPath } from "./paths";
+
+class InboundSignal {
+  constructor(private path: string) {}
+
+  /**
+   * Gets the current version of the signal. This version string changes every
+   * time the signal is emitted, and can be used to detect whether signal has
+   * been emitted between two timepoints.
+   * @returns The current signal version or null if the signal file could not be
+   * found
+   */
+  async getVersion() {
+    try {
+      return (await stat(this.path)).mtimeMs.toString();
+    } catch (err) {
+      if ((err as NodeJS.ErrnoException).code !== "ENOENT") {
+        throw err;
+      }
+
+      return null;
+    }
+  }
+}
+
+export function getInboundSignal(name: string) {
+  const signalDir = getSignalDirPath();
+  const path = join(signalDir, name);
+
+  return new InboundSignal(path);
+}