fix: update jar file with confirmation on configuration change

fixes #15

src/ExtensionConfiguration.ts

@@ -1,22 +1,33 @@
+import { Uri } from "vscode";
 import { getJavaConfiguration } from "./utils";
 
+export type GoogleJavaFormatVersion =
+    | `${number}.${number}.${number}`
+    | "latest";
+
 export interface GoogleJavaFormatConfiguration {
     executable?: string;
-    version?: string;
+    version?: GoogleJavaFormatVersion;
     extra?: string;
+    jarUri: Uri;
 }
 
 export class ExtensionConfiguration implements GoogleJavaFormatConfiguration {
     readonly executable?: string;
-    readonly version?: string;
+    readonly version?: GoogleJavaFormatVersion;
     readonly extra?: string;
+    jarUri: Uri = null!;
 
     constructor() {
         return new Proxy(this, this.handler);
     }
 
     private handler: ProxyHandler<ExtensionConfiguration> = {
         get(target, prop) {
+            if (prop === "jarUri") {
+                return target[prop];
+            }
+
             return getJavaConfiguration().get(
                 `format.settings.google.${String(prop)}`,
             );

src/GoogleJavaFormatterSync.ts

@@ -5,7 +5,6 @@ import { GoogleJavaFormatConfiguration } from "./ExtensionConfiguration";
 
 export default class GoogleJavaFormatterSync implements IGoogleJavaFormatter {
     constructor(
-        private executable: string,
         private config: GoogleJavaFormatConfiguration,
         private log: LogOutputChannel,
     ) {}
@@ -21,7 +20,7 @@ export default class GoogleJavaFormatterSync implements IGoogleJavaFormatter {
     public format(text: string, range?: [number, number]): Promise<string> {
         return new Promise<string>((resolve, reject) => {
             try {
-                let command = `java -jar ${this.executable}`;
+                let command = `java -jar ${this.config.jarUri.fsPath}`;
 
                 if (this.config.extra) {
                     command += ` ${this.config.extra}`;

src/extension.ts

@@ -1,11 +1,16 @@
-import { ExtensionContext, window } from "vscode";
-import getExtensionCacheFolder from "./getExtensionCacheFolder";
+import {
+    ConfigurationChangeEvent,
+    ExtensionContext,
+    ProgressLocation,
+    window,
+    workspace,
+} from "vscode";
 import { ExtensionConfiguration } from "./ExtensionConfiguration";
-import getJarLocalPathFromConfig from "./getJarLocalPathFromConfig";
 import GoogleJavaFormatEditProvider from "./GoogleJavaFormatEditProvider";
 import GoogleJavaFormatEditService from "./GoogleJavaFormatEditService";
 import GoogleJavaFormatterSync from "./GoogleJavaFormatterSync";
-import { IGoogleJavaFormatter } from "./IGoogleJavaFormatter";
+import getExtensionCacheFolder from "./getExtensionCacheFolder";
+import getJarLocalPathFromConfig from "./getJarLocalPathFromConfig";
 
 export async function activate(context: ExtensionContext) {
     const log = window.createOutputChannel("Google Java Format for VS Code", {
@@ -16,17 +21,53 @@ export async function activate(context: ExtensionContext) {
     const config = new ExtensionConfiguration();
     const cacheDir = getExtensionCacheFolder(context);
 
-    const jarLocalPath = await getJarLocalPathFromConfig({
-        cacheDir,
-        log,
-        config,
-    }).then((uri) => uri.fsPath);
+    const configureJarFile = async () => {
+        config.jarUri = await getJarLocalPathFromConfig({
+            cacheDir,
+            log,
+            config,
+        });
+    };
+    await configureJarFile();
 
-    const formatter: IGoogleJavaFormatter = new GoogleJavaFormatterSync(
-        jarLocalPath,
-        config,
-        log,
+    const configurationChangeListener = async (
+        event: ConfigurationChangeEvent,
+    ) => {
+        if (
+            // check if configuration updated
+            !event.affectsConfiguration("java.format.settings.google")
+        ) {
+            // jar update not needed
+            return;
+        }
+
+        log.info("Configuration change detected.");
+        const action = await window.showInformationMessage(
+            "Configuration change detected. Update jar file?",
+            "Update",
+            "Ignore",
+        );
+
+        if (action !== "Update") {
+            log.debug("Change ignored.");
+            return;
+        }
+
+        log.debug("Updating jar file...");
+        window.withProgress(
+            {
+                location: ProgressLocation.Notification,
+                title: "Updating jar file...",
+                cancellable: false,
+            },
+            configureJarFile,
+        );
+    };
+    context.subscriptions.push(
+        workspace.onDidChangeConfiguration(configurationChangeListener),
     );
+
+    const formatter = new GoogleJavaFormatterSync(config, log);
     context.subscriptions.push(formatter.init());
 
     const editProvider = new GoogleJavaFormatEditProvider(formatter, log);