Progressive Web Apps

import type { MetadataRoute } from 'next'

export default function manifest(): MetadataRoute.Manifest {
  return {
    name: 'Next.js PWA',
    short_name: 'NextPWA',
    description: 'A Progressive Web App built with Next.js',
    start_url: '/',
    display: 'standalone',
    background_color: '#ffffff',
    theme_color: '#000000',
    icons: [
      {
        src: '/icon-192x192.png',
        sizes: '192x192',
        type: 'image/png',
      },
      {
        src: '/icon-512x512.png',
        sizes: '512x512',
        type: 'image/png',
      },
    ],
  }
}

'use client'

import { useState, useEffect } from 'react'
import { subscribeUser, unsubscribeUser, sendNotification } from './actions'

function urlBase64ToUint8Array(base64String: string) {
  const padding = '='.repeat((4 - (base64String.length % 4)) % 4)
  const base64 = (base64String + padding).replace(/-/g, '+').replace(/_/g, '/')
  const rawData = window.atob(base64)
  const outputArray = new Uint8Array(rawData.length)
  for (let i = 0; i < rawData.length; ++i) {
    outputArray[i] = rawData.charCodeAt(i)
  }
  return outputArray
}

function PushNotificationManager() {
  const [isSupported, setIsSupported] = useState(false)
  const [subscription, setSubscription] = useState<PushSubscription | null>(null)
  const [message, setMessage] = useState('')

  useEffect(() => {
    if ('serviceWorker' in navigator && 'PushManager' in window) {
      setIsSupported(true)
      registerServiceWorker()
    }
  }, [])

  async function registerServiceWorker() {
    const registration = await navigator.serviceWorker.register('/sw.js', {
      scope: '/',
      updateViaCache: 'none',
    })
    const sub = await registration.pushManager.getSubscription()
    setSubscription(sub)
  }

  async function subscribeToPush() {
    const registration = await navigator.serviceWorker.ready
    const sub = await registration.pushManager.subscribe({
      userVisibleOnly: true,
      applicationServerKey: urlBase64ToUint8Array(
        process.env.NEXT_PUBLIC_VAPID_PUBLIC_KEY!
      ),
    })
    setSubscription(sub)
    const serializedSub = JSON.parse(JSON.stringify(sub))
    await subscribeUser(serializedSub)
  }

  async function unsubscribeFromPush() {
    await subscription?.unsubscribe()
    setSubscription(null)
    await unsubscribeUser()
  }

  if (!isSupported) {
    return <p>Push notifications are not supported in this browser.</p>
  }

  return (
    <div>
      <h3>Push Notifications</h3>
      {subscription ? (
        <>
          <p>You are subscribed to push notifications.</p>
          <button onClick={unsubscribeFromPush}>Unsubscribe</button>
          <input
            type="text"
            placeholder="Enter notification message"
            value={message}
            onChange={(e) => setMessage(e.target.value)}
          />
          <button onClick={() => sendNotification(message)}>Send Test</button>
        </>
      ) : (
        <>
          <p>You are not subscribed to push notifications.</p>
          <button onClick={subscribeToPush}>Subscribe</button>
        </>
      )}
    </div>
  )
}

function InstallPrompt() {
  const [isIOS, setIsIOS] = useState(false)
  const [isStandalone, setIsStandalone] = useState(false)

  useEffect(() => {
    setIsIOS(/iPad|iPhone|iPod/.test(navigator.userAgent))
    setIsStandalone(window.matchMedia('(display-mode: standalone)').matches)
  }, [])

  if (isStandalone) return null

  return (
    <div>
      <h3>Install App</h3>
      {isIOS && (
        <p>Tap the share button and then "Add to Home Screen" to install this app.</p>
      )}
    </div>
  )
}

export default function Page() {
  return (
    <div>
      <PushNotificationManager />
      <InstallPrompt />
    </div>
  )
}

'use server'

import webpush from 'web-push'

webpush.setVapidDetails(
  'mailto:[email protected]',
  process.env.NEXT_PUBLIC_VAPID_PUBLIC_KEY!,
  process.env.VAPID_PRIVATE_KEY!
)

let subscription: PushSubscription | null = null

export async function subscribeUser(sub: PushSubscription) {
  subscription = sub
  // In production: store in database
  return { success: true }
}

export async function unsubscribeUser() {
  subscription = null
  // In production: remove from database
  return { success: true }
}

export async function sendNotification(message: string) {
  if (!subscription) throw new Error('No subscription available')

  try {
    await webpush.sendNotification(
      subscription,
      JSON.stringify({
        title: 'Test Notification',
        body: message,
        icon: '/icon.png',
      })
    )
    return { success: true }
  } catch (error) {
    console.error('Error sending push notification:', error)
    return { success: false, error: 'Failed to send notification' }
  }
}

npm install -g web-push
web-push generate-vapid-keys

NEXT_PUBLIC_VAPID_PUBLIC_KEY=your_public_key_here
VAPID_PRIVATE_KEY=your_private_key_here

self.addEventListener('push', function (event) {
  if (event.data) {
    const data = event.data.json()
    const options = {
      body: data.body,
      icon: data.icon || '/icon.png',
      badge: '/badge.png',
      vibrate: [100, 50, 100],
      data: {
        dateOfArrival: Date.now(),
        primaryKey: '2',
      },
    }
    event.waitUntil(self.registration.showNotification(data.title, options))
  }
})

self.addEventListener('notificationclick', function (event) {
  event.notification.close()
  event.waitUntil(clients.openWindow('https://your-website.com'))
})

module.exports = {
  async headers() {
    return [
      {
        source: '/(.*)',
        headers: [
          { key: 'X-Content-Type-Options', value: 'nosniff' },
          { key: 'X-Frame-Options', value: 'DENY' },
          { key: 'Referrer-Policy', value: 'strict-origin-when-cross-origin' },
        ],
      },
      {
        source: '/sw.js',
        headers: [
          { key: 'Content-Type', value: 'application/javascript; charset=utf-8' },
          { key: 'Cache-Control', value: 'no-cache, no-store, must-revalidate' },
          { key: 'Content-Security-Policy', value: "default-src 'self'; script-src 'self'" },
        ],
      },
    ]
  },
}