<template>
  <div class="chat-fullscreen">
    <!-- Close button + connection indicator (desktop: top-right pill) -->
    <div class="chat-mode-pill hidden md:flex">
      <button class="chat-close-btn" :aria-label="t('chat.closeAssistant')" @click="closeChat">
        <svg class="w-4 h-4" aria-hidden="true" fill="none" stroke="currentColor" viewBox="0 0 24 24">
          <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M6 18L18 6M6 6l12 12" />
        </svg>
        <span class="text-xs font-medium">{{ t('chat.close') }}</span>
      </button>
      <div
        v-if="aiuiConnected"
        class="w-2 h-2 rounded-full bg-green-400 ml-2 shadow-[0_0_6px_rgba(74,222,128,0.5)]"
        :title="t('chat.aiuiConnected')"
      />
    </div>

    <!-- Loading indicator while iframe loads. pointer-events:none on the
         wrapper (see <style>) so this never blocks clicks reaching the
         iframe underneath even while shown; the bounded timeout below
         (see aiuiLoadTimedOut) additionally guarantees it disappears
         outright regardless of backend/handshake state, so it can never
         wedge the UI permanently. -->
    <Transition name="fade">
      <div v-if="aiuiUrl && !aiuiConnected && !aiuiLoadTimedOut" class="chat-loading" role="status" aria-live="polite">
        <div class="glass-card p-8 flex flex-col items-center gap-4">
          <div class="chat-loading-spinner" aria-hidden="true" />
          <p class="text-sm text-white/60">{{ t('chat.loadingAssistant') }}</p>
        </div>
      </div>
    </Transition>

    <!-- AIUI iframe — on mobile, leave room for close bar + tab bar at bottom -->
    <iframe
      v-if="aiuiUrl"
      ref="aiuiFrame"
      :src="aiuiUrl"
      :title="t('chat.aiAssistant')"
      class="chat-iframe chat-iframe-mobile"
      allow="microphone"
      style="background: transparent"
    />

    <!-- Fallback when no AIUI URL configured -->
    <div v-else class="chat-placeholder">
      <div class="chat-placeholder-inner">
        <div class="chat-placeholder-icon">
          <svg class="w-8 h-8 text-white/40" aria-hidden="true" fill="none" stroke="currentColor" viewBox="0 0 24 24">
            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M8 12h.01M12 12h.01M16 12h.01M21 12c0 4.418-4.03 8-9 8a9.863 9.863 0 01-4.255-.949L3 20l1.395-3.72C3.512 15.042 3 13.574 3 12c0-4.418 4.03-8 9-8s9 3.582 9 8z" />
          </svg>
        </div>
        <h2 class="text-2xl font-semibold text-white mb-2">{{ t('chat.aiAssistant') }}</h2>
        <p class="text-white/60 mb-4 leading-relaxed">
          {{ t('chat.notConfigured') }}
        </p>
        <p class="text-xs text-white/30">
          {{ t('chat.deployCta') }}
        </p>
      </div>
    </div>

  </div>
</template>

<script setup lang="ts">
import { ref, computed, onActivated, onBeforeUnmount, onDeactivated, onMounted, watch } from 'vue'
import { useRoute, useRouter } from 'vue-router'
import { useI18n } from 'vue-i18n'
import { ContextBroker } from '@/services/contextBroker'
import { IS_DEMO } from '@/composables/useDemoIntro'

const { t } = useI18n()

const router = useRouter()
const route = useRoute()
const aiuiFrame = ref<HTMLIFrameElement | null>(null)
const aiuiConnected = ref(false)
// Belt-and-suspenders backstop (2026-07-30 live-testing follow-up): the
// loading overlay must never be able to wedge the UI permanently regardless
// of AIUI/backend state — a broken handshake, a misconfigured origin, or the
// AI provider being unreachable must not leave the user staring at a
// spinner forever with no way to interact with the panel underneath. This
// timeout dismisses the overlay unconditionally after a bounded wait even if
// 'ready' never arrives; it does not affect aiuiConnected itself (the
// connection indicator dot still reflects the real state).
const AIUI_LOAD_TIMEOUT_MS = 8000
const aiuiLoadTimedOut = ref(false)
let loadTimeout: ReturnType<typeof setTimeout> | null = null
let broker: ContextBroker | null = null

// D-14 presentation flags (Phase 02 Plan 07, 02-AIUI-D14.md): AIUI opens
// already expanded (chatExpanded) and, on a mobile viewport, on its chat view
// rather than its context view (mobileChat). Both are static strings — never
// derived from a reactive viewport read, connection state, or timestamp — so
// the computed below has no reactive dependencies and its value never
// changes after first evaluation, which is exactly what keeps the iframe
// `src` byte-identical across re-renders, resizes, and deactivate/reactivate
// cycles (the load-bearing constraint that lets the AIUI panel survive a tab
// switch without reloading). AIUI decides how to apply mobileChat against its
// own viewport rather than neode-ui's, per 02-AIUI-D14.md's D-14b rationale.
const D14_FLAGS = 'chatExpanded=true&mobileChat=true'

const aiuiUrl = computed(() => {
  // Demo: ?mockArchy makes AIUI use its built-in mock node data (apps, system,
  // network, wallet, bitcoin, files) and &seed pre-loads the example chats.
  const demo = IS_DEMO ? '&mockArchy=1&seed=1' : ''
  const envUrl = import.meta.env.VITE_AIUI_URL
  if (envUrl) return `${envUrl}?embedded=true&hideClose=true&${D14_FLAGS}${demo}`
  if (import.meta.env.PROD || IS_DEMO) return `/aiui/?embedded=true&hideClose=true&${D14_FLAGS}${demo}`
  return ''
})

// ⌘K → "Talk to AIUI about it" hands the typed text over as `?ask=`.
//
// It is delivered by postMessage, NOT by adding a query param to `aiuiUrl`.
// That is deliberate: the comment on D14_FLAGS above explains that aiuiUrl must
// have no reactive dependencies so the iframe `src` stays byte-identical and
// AIUI survives a tab switch. Threading `ask` through the URL would rebuild the
// src on every question and reload AIUI, discarding the conversation — the
// exact opposite of what this feature is for.
//
// The ask is queued rather than sent directly, because the common case is
// arriving from ⌘K on a cold Chat tab where the iframe has not handshaked yet.
// `ready` flushes it.
const pendingAsk = ref('')

function flushAsk() {
  const text = pendingAsk.value
  if (!text || !aiuiConnected.value) return
  const frame = aiuiFrame.value
  if (!frame?.contentWindow || !aiuiUrl.value) return
  let targetOrigin: string
  try {
    targetOrigin = new URL(aiuiUrl.value, window.location.origin).origin
  } catch { return }
  frame.contentWindow.postMessage({ type: 'chat:prefill', text }, targetOrigin)
  pendingAsk.value = ''
  // Drop ask/askedAt from the URL so a refresh or a back-nav does not re-ask.
  const { ask: _a, askedAt: _t, ...rest } = route.query
  router.replace({ path: route.path, query: rest })
}

watch(
  () => route.query.askedAt,
  () => {
    const ask = route.query.ask
    if (!ask) return
    pendingAsk.value = String(ask)
    flushAsk()
  },
  { immediate: true },
)

function closeChat() {
  if (window.history.length > 1) {
    router.back()
  } else {
    router.push('/dashboard')
  }
}

function onAiuiMessage(event: MessageEvent) {
  if (!aiuiUrl.value) return
  // Validate origin — only accept messages from AIUI
  try {
    const expected = new URL(aiuiUrl.value, window.location.origin).origin
    if (event.origin !== expected) return
  } catch { return }
  // Listen for ready messages from AIUI iframe
  if (event.data?.type === 'ready') {
    aiuiConnected.value = true
    if (loadTimeout) { clearTimeout(loadTimeout); loadTimeout = null }
    // A ⌘K ask that arrived before the handshake is waiting — send it now.
    flushAsk()
  }
}

// The window message listener and the ContextBroker are only-while-visible:
// Chat is a main tab that survives a tab switch (KeepAlive), so both follow
// activation rather than mount. Idempotent — remove/stop any existing
// listener/broker before starting a new one, so two consecutive activations
// (Vue fires onActivated on first mount too) never double-arm either.
// `aiuiConnected` is set by a one-time 'ready' message from the iframe; once
// the iframe survives deactivation that message will not be re-sent on
// re-entry, so it must NOT be reset on deactivate.
function armChatLive() {
  window.removeEventListener('message', onAiuiMessage)
  window.addEventListener('message', onAiuiMessage)
  broker?.stop()
  broker = null
  if (aiuiUrl.value) {
    broker = new ContextBroker(aiuiFrame, aiuiUrl.value)
    broker.start()
  }
  if (loadTimeout) clearTimeout(loadTimeout)
  loadTimeout = null
  if (aiuiUrl.value && !aiuiConnected.value) {
    loadTimeout = setTimeout(() => {
      aiuiLoadTimedOut.value = true
      loadTimeout = null
    }, AIUI_LOAD_TIMEOUT_MS)
  }
}
onActivated(() => armChatLive())

onDeactivated(() => {
  window.removeEventListener('message', onAiuiMessage)
  broker?.stop()
  broker = null
  if (loadTimeout) { clearTimeout(loadTimeout); loadTimeout = null }
})

// onActivated is a no-op outside a <KeepAlive> boundary — call it directly
// here too so a bare mount (a unit test, or any future non-KeepAlive usage)
// still gets the listener and the AIUI ContextBroker. Idempotent, so the
// redundant pass this causes on a KeepAlive-wrapped first mount is harmless.
onMounted(() => armChatLive())

onBeforeUnmount(() => {
  window.removeEventListener('message', onAiuiMessage)
  broker?.stop()
  broker = null
  if (loadTimeout) { clearTimeout(loadTimeout); loadTimeout = null }
})
</script>

<style scoped>
.chat-loading {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
  /* Never let the loading state itself block interaction with the iframe
     underneath — it has no interactive content of its own, so there is
     nothing here that needs to capture clicks. */
  pointer-events: none;
}

.chat-loading-spinner {
  width: 32px;
  height: 32px;
  border: 3px solid rgba(255, 255, 255, 0.1);
  border-top-color: #fb923c;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.fade-enter-active,
.fade-leave-active {
  transition: opacity 0.3s ease;
}

.fade-enter-from,
.fade-leave-to {
  opacity: 0;
}

</style>
