kyber

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// This optional code is used to register a service worker.
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// register() is not called by default.
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// This lets the app load faster on subsequent visits in production, and gives
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// it offline capabilities. However, it also means that developers (and users)
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// will only see deployed updates on subsequent visits to a page, after all the
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// existing tabs open on the page have been closed, since previously cached
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// resources are updated in the background.
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// To learn more about the benefits of this model and instructions on how to
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// opt-in, read https://cra.link/PWA
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const isLocalhost = Boolean(
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  window.location.hostname === 'localhost' ||
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    // [::1] is the IPv6 localhost address.
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    window.location.hostname === '[::1]' ||
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    // 127.0.0.0/8 are considered localhost for IPv4.
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    window.location.hostname.match(/^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/)
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)
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type Config = {
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  onSuccess?: (registration: ServiceWorkerRegistration) => void;
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  onUpdate?: (registration: ServiceWorkerRegistration) => void;
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};
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export function register(config?: Config) {
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  if (process.env.NODE_ENV === 'production' && 'serviceWorker' in navigator) {
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    // The URL constructor is available in all browsers that support SW.
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    const publicUrl = new URL(process.env.PUBLIC_URL, window.location.href)
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    if (publicUrl.origin !== window.location.origin) {
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      // Our service worker won't work if PUBLIC_URL is on a different origin
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      // from what our page is served on. This might happen if a CDN is used to
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      // serve assets; see https://github.com/facebook/create-react-app/issues/2374
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      return
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    }
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    window.addEventListener('load', () => {
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      const swUrl = `${process.env.PUBLIC_URL}/service-worker.js`
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      if (isLocalhost) {
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        // This is running on localhost. Let's check if a service worker still exists or not.
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        checkValidServiceWorker(swUrl, config)
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        // Add some additional logging to localhost, pointing developers to the
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        // service worker/PWA documentation.
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        navigator.serviceWorker.ready.then(() => {
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          console.log(
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            'This web app is being served cache-first by a service ' +
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              'worker. To learn more, visit https://cra.link/PWA'
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          )
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        })
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      } else {
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        // Is not localhost. Just register service worker
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        registerValidSW(swUrl, config)
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      }
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    })
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  }
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}
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function registerValidSW(swUrl: string, config?: Config) {
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  navigator.serviceWorker
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    .register(swUrl)
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    .then((registration) => {
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      registration.onupdatefound = () => {
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        const installingWorker = registration.installing
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        if (installingWorker == null) {
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          return
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        }
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        installingWorker.onstatechange = () => {
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          if (installingWorker.state === 'installed') {
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            if (navigator.serviceWorker.controller) {
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              // At this point, the updated precached content has been fetched,
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              // but the previous service worker will still serve the older
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              // content until all client tabs are closed.
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              console.log(
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                'New content is available and will be used when all ' +
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                  'tabs for this page are closed. See https://cra.link/PWA.'
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              )
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              // Execute callback
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              if (config && config.onUpdate) {
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                config.onUpdate(registration)
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              }
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            } else {
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              // At this point, everything has been precached.
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              // It's the perfect time to display a
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              // "Content is cached for offline use." message.
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              console.log('Content is cached for offline use.')
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              // Execute callback
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              if (config && config.onSuccess) {
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                config.onSuccess(registration)
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              }
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            }
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          }
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        }
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      }
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    })
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    .catch((error) => {
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      console.error('Error during service worker registration:', error)
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    })
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}
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function checkValidServiceWorker(swUrl: string, config?: Config) {
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  // Check if the service worker can be found. If it can't reload the page.
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  fetch(swUrl, {
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    headers: { 'Service-Worker': 'script' },
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  })
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    .then((response) => {
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      // Ensure service worker exists, and that we really are getting a JS file.
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      const contentType = response.headers.get('content-type')
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      if (
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        response.status === 404 ||
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        (contentType != null && contentType.indexOf('javascript') === -1)
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      ) {
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        // No service worker found. Probably a different app. Reload the page.
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        navigator.serviceWorker.ready.then((registration) => {
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          registration.unregister().then(() => {
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            window.location.reload()
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          })
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        })
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      } else {
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        // Service worker found. Proceed as normal.
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        registerValidSW(swUrl, config)
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      }
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    })
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    .catch(() => {
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      console.log('No internet connection found. App is running in offline mode.')
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    })
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}
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export function unregister() {
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  if ('serviceWorker' in navigator) {
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    navigator.serviceWorker.ready
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      .then((registration) => {
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        registration.unregister()
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      })
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      .catch((error) => {
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        console.error(error.message)
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      })
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  }
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}