<template>
  <BaseModal :show="showUpdatePrompt" title="Update Available" z-index="z-[9999]" @close="dismissUpdate">
          <p class="text-white/80 mb-6">
            A new version of Archipelago is available. Update now to get the latest features and fixes.
          </p>
          <template #footer>
            <div class="flex gap-3 justify-end">
              <button
                @click="dismissUpdate"
                class="px-4 py-2 glass-button rounded-lg text-sm font-medium"
              >
                Later
              </button>
              <button
                @click="handleUpdate"
                class="px-4 py-2 glass-button glass-button-sm rounded-lg text-sm font-medium"
              >
                Update Now
              </button>
            </div>
          </template>
  </BaseModal>
</template>

<script setup lang="ts">
import { ref, onMounted } from 'vue'
import BaseModal from '@/components/BaseModal.vue'

const showUpdatePrompt = ref(false)
let updateCallback: (() => Promise<void>) | null = null

onMounted(() => {
  // Listen for service worker updates
  if ('serviceWorker' in navigator) {
    navigator.serviceWorker.addEventListener('controllerchange', () => {
      // Service worker updated, reload the page
      window.location.reload()
    })

    // Check for updates periodically
    const checkForUpdates = async () => {
      const registration = await navigator.serviceWorker.getRegistration()
      if (registration) {
        await registration.update()
      }
    }

    // Check for updates every 5 minutes
    setInterval(checkForUpdates, 5 * 60 * 1000)

    // Check when user returns to tab (helps with cached PWA)
    document.addEventListener('visibilitychange', () => {
      if (document.visibilityState === 'visible') {
        checkForUpdates()
      }
    })

    // Listen for updatefound event
    navigator.serviceWorker.getRegistration().then((registration) => {
      if (registration) {
        registration.addEventListener('updatefound', () => {
          const newWorker = registration.installing
          if (newWorker) {
            newWorker.addEventListener('statechange', () => {
              if (newWorker.state === 'installed' && navigator.serviceWorker.controller) {
                updateCallback = async () => {
                  if (newWorker.state === 'installed' && registration.waiting) {
                    // Skip waiting and activate the new service worker
                    registration.waiting.postMessage({ type: 'SKIP_WAITING' })
                  }
                }
                // The kiosk is unattended — nobody can click "Update Now",
                // so it kept running stale bundles forever (stale FIPS state,
                // old assets). Auto-apply there; prompt everywhere else.
                if (localStorage.getItem('kiosk')) {
                  updateCallback()
                } else {
                  showUpdatePrompt.value = true
                }
              }
            })
          }
        })
      }
    })
  }
})

function dismissUpdate() {
  showUpdatePrompt.value = false
}

async function handleUpdate() {
  if (updateCallback) {
    await updateCallback()
  }
}
</script>
