added build-time information

vite.config.js

@@ -1,10 +1,52 @@
-import { defineConfig } from 'vite'
-import vue from '@vitejs/plugin-vue'
+import { defineConfig } from 'vite';
+import vue from '@vitejs/plugin-vue';
+import fs from 'fs';
+import { resolve } from 'path';
+
+const packageJson = JSON.parse(fs.readFileSync('./package.json', 'utf8'));
+const appVersion = packageJson.version;
+
+// Options for date formatting
+const dateTimeFormatOptions = {
+  year: 'numeric', month: '2-digit', day: '2-digit',
+  hour: '2-digit', minute: '2-digit', second: '2-digit',
+  hour12: false // Use 24-hour format
+};
+// Generate build time string using Slovak locale
+const appBuildTime = new Date().toLocaleString('sk-SK', dateTimeFormatOptions);
+
 
-// https://vitejs.dev/config/
 export default defineConfig({
   plugins: [vue()],
   server: {
     port: 8080
+   },
+  define: {
+    'import.meta.env.VITE_APP_BUILD_TIME': JSON.stringify(appBuildTime),
+    '__APP_CACHE_VERSION__': JSON.stringify(`nexus-timer-cache-v${appVersion}-${Date.now()}`)
+  },
+  build: {
+    rollupOptions: {
+      input: {
+        main: resolve(__dirname, 'index.html'),
+        sw: resolve(__dirname, 'src/sw.js') // Assuming sw.js is now in src
+      },
+      output: {
+        entryFileNames: assetInfo => {
+          // Output service-worker.js to the root of the dist directory
+          if (assetInfo.name === 'sw') {
+            return 'service-worker.js'; // Ensure consistent name
+          }
+          // Default naming for other entry points/chunks
+          return 'assets/[name]-[hash].js';
+        },
+        // For chunks, if any are generated from sw.js (unlikely for simple SW)
+        chunkFileNames: 'assets/[name]-[hash].js',
+        assetFileNames: 'assets/[name]-[hash].[ext]',
+      }
+    },
+    // Set to false if you don't want to empty the dist dir on each build
+    // but usually true is good for clean builds.
+    emptyOutDir: true, 
   }
-})
+});