/*
 * NIS2 Agile — PWA bootstrap
 * Registra il service worker e gestisce l'UI di installazione (Android + iOS).
 * Vanilla JS, nessuna dipendenza. Localizzato IT/EN (chiave i18n: 'nis2_lang').
 */
(function () {
  'use strict';

  // --- i18n minimale, allineato a i18n.js (localStorage 'nis2_lang') ---
  function lang() {
    try { return (localStorage.getItem('nis2_lang') || 'it').slice(0, 2); }
    catch (e) { return 'it'; }
  }
  var STR = {
    it: {
      install: 'Installa app',
      banner: 'Installa NIS2 Agile sul dispositivo per un accesso più rapido.',
      ios: 'Per installare: tocca Condividi e poi "Aggiungi a Home".',
      close: 'Chiudi'
    },
    en: {
      install: 'Install app',
      banner: 'Install NIS2 Agile on your device for faster access.',
      ios: 'To install: tap Share, then "Add to Home Screen".',
      close: 'Close'
    }
  };
  function t(k) { var l = lang(); return (STR[l] && STR[l][k]) || STR.it[k]; }

  function isStandalone() {
    return (window.matchMedia && window.matchMedia('(display-mode: standalone)').matches)
        || window.navigator.standalone === true;
  }

  // --- 1. Registrazione service worker ---
  if ('serviceWorker' in navigator) {
    window.addEventListener('load', function () {
      navigator.serviceWorker.register('/sw.js', { scope: '/' })
        .catch(function (err) { console.warn('[pwa] SW registration failed', err); });
    });
  }

  // Gia' installata (standalone): niente banner di installazione.
  if (isStandalone()) return;

  // --- UI banner sobrio, indipendente dal CSS dell'app ---
  function makeBanner(message, withInstallBtn) {
    var bar = document.createElement('div');
    bar.setAttribute('role', 'region');
    bar.setAttribute('aria-label', t('install'));
    bar.style.cssText = 'position:fixed;left:12px;right:12px;bottom:12px;z-index:9999;'
      + 'background:#0066CC;color:#fff;border-radius:10px;padding:12px 14px;'
      + 'box-shadow:0 6px 24px rgba(0,0,0,.25);display:flex;align-items:center;gap:10px;'
      + 'font-family:system-ui,Arial,sans-serif;font-size:.95rem;max-width:560px;margin:0 auto;';

    var txt = document.createElement('span');
    txt.style.cssText = 'flex:1;line-height:1.35;';
    txt.textContent = message;
    bar.appendChild(txt);

    var btnInstall = null;
    if (withInstallBtn) {
      btnInstall = document.createElement('button');
      btnInstall.type = 'button';
      btnInstall.textContent = t('install');
      btnInstall.style.cssText = 'background:#fff;color:#0066CC;border:0;border-radius:8px;'
        + 'padding:10px 16px;font-weight:600;min-height:44px;cursor:pointer;white-space:nowrap;';
      bar.appendChild(btnInstall);
    }

    var btnClose = document.createElement('button');
    btnClose.type = 'button';
    btnClose.setAttribute('aria-label', t('close'));
    btnClose.textContent = '✕';
    btnClose.style.cssText = 'background:transparent;color:#fff;border:0;font-size:1.1rem;'
      + 'line-height:1;min-width:44px;min-height:44px;cursor:pointer;';
    bar.appendChild(btnClose);

    document.body.appendChild(bar);
    return { bar: bar, btnInstall: btnInstall, btnClose: btnClose };
  }

  // --- 2. Android / Chrome: beforeinstallprompt ---
  var deferred = null;
  var DISMISS_KEY = 'pwa-install-dismissed';
  function dismissed() { try { return localStorage.getItem(DISMISS_KEY) === '1'; } catch (e) { return false; } }
  function setDismissed() { try { localStorage.setItem(DISMISS_KEY, '1'); } catch (e) {} }

  window.addEventListener('beforeinstallprompt', function (e) {
    e.preventDefault();
    deferred = e;
    if (dismissed()) return;
    try {
      var ui = makeBanner(t('banner'), true);
      ui.btnInstall.addEventListener('click', function () {
        ui.bar.remove();
        if (!deferred) return;
        deferred.prompt();
        if (deferred.userChoice && deferred.userChoice.finally) {
          deferred.userChoice.finally(function () { deferred = null; });
        } else { deferred = null; }
      });
      ui.btnClose.addEventListener('click', function () { ui.bar.remove(); setDismissed(); });
    } catch (err) { console.warn('[pwa] banner error', err); }
  });

  window.addEventListener('appinstalled', function () {
    deferred = null;
    setDismissed();
  });

  // --- 3. iOS Safari: nessun beforeinstallprompt -> hint manuale (una volta) ---
  try {
    var ua = navigator.userAgent || '';
    var isIOS = /iphone|ipad|ipod/i.test(ua)
      || (/Macintosh/.test(ua) && 'ontouchend' in document); // iPad iPadOS desktop-mode
    var isSafari = /safari/i.test(ua) && !/crios|fxios|edgios|android/i.test(ua);
    var IOS_KEY = 'pwa-ios-hint-dismissed';
    var iosDismissed = (function () { try { return localStorage.getItem(IOS_KEY) === '1'; } catch (e) { return false; } })();
    if (isIOS && isSafari && !iosDismissed) {
      window.addEventListener('load', function () {
        var ui = makeBanner(t('ios'), false);
        ui.btnClose.addEventListener('click', function () {
          ui.bar.remove();
          try { localStorage.setItem(IOS_KEY, '1'); } catch (e) {}
        });
      });
    }
  } catch (err) { console.warn('[pwa] ios hint error', err); }
})();