/**
 * Native app lifecycle polish for the bundled Capacitor app (Phase 1):
 *  - Hardware BACK button: navigate back within the mobile flow; at the mobile home require a
 *    second press within 2s to exit, so a stray gesture can't drop someone out of a half-finished
 *    receipt/return. (Default Capacitor behaviour exits the app on every back press at the root.)
 *  - Status bar: paint it to match the mobile theme (dark canvas by default) and re-apply on resume.
 *  - On resume: nudge the existing token keep-alive (the API plugin also listens to visibilitychange).
 *
 * App-only + fail-soft: early-returns on the web build (__CAP_BUILD__ undefined); also dropped from the
 * web bundle by the nuxt.config app:resolve hook (name 'native-lifecycle'). @capacitor/app and
 * @capacitor/status-bar are DYNAMICALLY imported so the web build never loads them. Any failure is
 * swallowed — the app just keeps the default native behaviour.
 */

// Injected by Vite only in the app build (see nuxt.config.ts).
declare const __CAP_BUILD__: boolean | undefined

export default defineNuxtPlugin(() => {
  if (typeof __CAP_BUILD__ === 'undefined') return // web build → no-op
  if (!process.client) return

  const router = useRouter()

  // ---- hardware back button + double-press-to-exit guard ----
  const HOME = '/mobile'
  let lastBackAt = 0

  const flashExitHint = () => {
    try {
      const el = document.createElement('div')
      el.textContent = 'Zum Beenden erneut „Zurück“ drücken'
      Object.assign(el.style, {
        position: 'fixed', left: '50%', bottom: 'calc(24px + env(safe-area-inset-bottom))',
        transform: 'translateX(-50%)', background: 'rgba(0,0,0,0.85)', color: '#fff',
        padding: '10px 18px', borderRadius: '999px', fontSize: '14px', zIndex: '99999',
        pointerEvents: 'none', maxWidth: '90vw', textAlign: 'center',
      })
      document.body.appendChild(el)
      setTimeout(() => { try { el.remove() } catch { /* gone */ } }, 1900)
    } catch { /* DOM unavailable */ }
  }

  const setupBackButton = async () => {
    try {
      const { App } = await import('@capacitor/app')
      App.addListener('backButton', ({ canGoBack }: any) => {
        const path = router.currentRoute.value.path
        const atHome = path === HOME || path === HOME + '/'
        if (!atHome && (canGoBack || window.history.length > 1)) {
          router.back()
          return
        }
        if (!atHome) {
          navigateTo(HOME)
          return
        }
        // At the mobile home: confirm exit via a quick double-press.
        const now = Date.now()
        if (now - lastBackAt < 2000) {
          App.exitApp()
        } else {
          lastBackAt = now
          flashExitHint()
          try { useFeedback().warning() } catch { /* ignore */ }
        }
      })

      // Keep the session warm when the app returns to the foreground.
      App.addListener('appStateChange', ({ isActive }: any) => {
        if (isActive) window.dispatchEvent(new Event('visibilitychange'))
      })
    } catch (e: any) {
      console.warn('[native-lifecycle] back-button setup failed:', e?.message)
    }
  }

  // ---- status bar theming ----
  const isDark = () => {
    try {
      return document.documentElement.classList.contains('dark')
        || document.documentElement.getAttribute('data-mode') === 'dark'
        || (window.localStorage?.getItem('logship_theme') || '').includes('dark')
    } catch { return true } // mobile canvas is dark by default
  }

  const applyStatusBar = async () => {
    try {
      const { StatusBar, Style } = await import('@capacitor/status-bar')
      const dark = isDark()
      await StatusBar.setOverlaysWebView({ overlay: false })
      // Style.Dark = light icons (for a dark bar); Style.Light = dark icons (for a light bar).
      await StatusBar.setStyle({ style: dark ? Style.Dark : Style.Light })
      await StatusBar.setBackgroundColor({ color: dark ? '#1a1a1a' : '#ffffff' })
    } catch { /* iOS / unsupported / not a native platform */ }
  }

  setupBackButton()
  applyStatusBar()
  // Re-apply after the app resumes (theme may have changed in another surface).
  document.addEventListener('visibilitychange', () => { if (!document.hidden) applyStatusBar() })
})