Revert "Revert "Migrate Postwoman to Nuxt.js (full Vue and SCSS support)""

assets/js/pwa.js

@@ -0,0 +1,54 @@
+export default () => {
+  //*** Determine whether or not the PWA has been installed. ***//
+
+  // Step 1: Check local storage
+  let pwaInstalled = localStorage.getItem('pwaInstalled') === 'yes';
+
+  // Step 2: Check if the display-mode is standalone. (Only permitted for PWAs.)
+  if (!pwaInstalled && window.matchMedia('(display-mode: standalone)').matches) {
+    localStorage.setItem('pwaInstalled', 'yes');
+    pwaInstalled = true;
+  }
+
+  // Step 3: Check if the navigator is in standalone mode. (Again, only permitted for PWAs.)
+  if (!pwaInstalled && window.navigator.standalone === true) {
+    localStorage.setItem('pwaInstalled', 'yes');
+    pwaInstalled = true;
+  }
+
+  //*** If the PWA has not been installed, show the install PWA prompt.. ***//
+  let deferredPrompt = null;
+  window.addEventListener('beforeinstallprompt', (event) => {
+    deferredPrompt = event;
+
+    // Show the install button if the prompt appeared.
+    if (!pwaInstalled) {
+      document.querySelector('#installPWA').style.display = 'block';
+    }
+  });
+
+  // When the app is installed, remove install prompts.
+  window.addEventListener('appinstalled', (event) => {
+    localStorage.setItem('pwaInstalled', 'yes');
+    pwaInstalled = true;
+    document.getElementById('installPWA').style.display = 'none';
+  });
+
+  // When the app is uninstalled, add the prompts back
+
+
+  return async () => {
+    if (deferredPrompt) {
+      deferredPrompt.prompt();
+      let outcome = await deferredPrompt.userChoice;
+
+      if (outcome === 'accepted') {
+        console.log('Postwoman was installed successfully.')
+      } else {
+        console.log('Postwoman could not be installed. (Installation rejected by user.)')
+      }
+      deferredPrompt = null;
+    }
+  };
+
+};