Rewrite locale file updating to be more Vue 3 friendly

_scripts/ProcessLocalesPlugin.js

@@ -40,17 +40,17 @@ class ProcessLocalesPlugin {
     /** @type {(updatedLocales: [string, string][]) => void|null} */
     this.notifyLocaleChange = null
 
-    if (this.hotReload) {
-      this.hotReloadScript = readFileSync(`${__dirname}/_hotReloadLocalesScript.js`, 'utf-8')
-    }
-
     this.loadLocales()
   }
 
   /** @param {import('webpack').Compiler} compiler  */
   apply(compiler) {
     const { CachedSource, RawSource } = compiler.webpack.sources;
-    const { Compilation } = compiler.webpack
+    const { Compilation, DefinePlugin } = compiler.webpack
+
+    new DefinePlugin({
+      'process.env.HOT_RELOAD_LOCALES': this.hotReload
+    }).apply(compiler)
 
     compiler.hooks.thisCompilation.tap(PLUGIN_NAME, (compilation) => {
       const IS_DEV_SERVER = !!compiler.watching
@@ -136,19 +136,6 @@ class ProcessLocalesPlugin {
         compilation.fileDependencies.addAll(this.filePaths)
       }
     })
-
-    compiler.hooks.emit.tap(PLUGIN_NAME, (compilation) => {
-      if (this.hotReload) {
-        // Find generated JavaScript output file (e.g. renderer.js or web.js)
-        // and inject the code snippet that listens for locale updates and replaces vue-i18n's locales
-
-        /** @type {string} */
-        const filename = [...[...compilation.chunks][0].files]
-          .find(file => file.endsWith('.js'))
-
-        compilation.assets[filename]._source._children.push(`\n${this.hotReloadScript}`)
-      }
-    })
   }
 
   loadLocales() {

src/renderer/i18n/index.js

@@ -50,4 +50,24 @@ export async function loadLocale(locale) {
   i18n.setLocaleMessage(locale, data)
 }
 
+// Set by _scripts/ProcessLocalesPlugin.js
+if (process.env.HOT_RELOAD_LOCALES) {
+  const websocket = new WebSocket('ws://localhost:9080/ws')
+
+  websocket.onmessage = (event) => {
+    const message = JSON.parse(event.data)
+
+    if (message.type === 'freetube-locale-update') {
+      for (const [locale, data] of message.data) {
+        // Only update locale data if it was already loaded
+        if (i18n.availableLocales.includes(locale)) {
+          const localeData = JSON.parse(data)
+
+          i18n.setLocaleMessage(locale, localeData)
+        }
+      }
+    }
+  }
+}
+
 export default i18n