<script setup lang="ts">
import { onBeforeUnmount, onMounted, ref, computed, watch } from 'vue'
import { useRoute } from 'vue-router'
import { useI18n } from 'vue-i18n'
import gsap from 'gsap'
import { ScrollTrigger } from 'gsap/ScrollTrigger'
import { useAppStore } from '~/stores/app'
import AppLogo from '~/components/common/AppLogo.vue'

gsap.registerPlugin(ScrollTrigger)
// gsap.registerPlugin(Observer)

const { t } = useI18n()
const route = useRoute()
const appStore = useAppStore()

// 导航菜单数据配置
const navItems = computed<Array<{ name: string, path: string }>>(() => [
  { name: t('nav.home'), path: '/' },
  { name: t('nav.studio'), path: '/studio' },
  { name: t('nav.work'), path: '/work' },
  { name: t('nav.news'), path: '/news' },
  { name: t('nav.contact'), path: '/contact' }
])

const topHeaderRef = ref<HTMLElement | null>(null)
const bottomHeaderRef = ref<HTMLElement | null>(null)
let topHeaderTween: gsap.core.Tween | null = null
let bottomHeaderScrollTrigger: ReturnType<typeof ScrollTrigger.create> | null = null
let isBottomHeaderVisible = false
let fallbackTimer: ReturnType<typeof setTimeout> | null = null

const setBottomHeaderVisible = (visible: boolean) => {
    if (!bottomHeaderRef.value || isBottomHeaderVisible === visible) {
      return
    }
  
    isBottomHeaderVisible = visible
  
    gsap.to(bottomHeaderRef.value, {
      yPercent: visible ? 0 : 150,
      autoAlpha: visible ? 1 : 0,
      duration: 0.45,
      ease: 'power2.out',
      overwrite: 'auto',
      force3D: true,
    })
  }

// 定义一个供外部或延迟调用的入场动画方法
const playHeaderIntro = () => {
  if (!topHeaderRef.value) return

  // 如果已经触发过，清理可能存在的保底定时器
  if (fallbackTimer) {
    clearTimeout(fallbackTimer)
    fallbackTimer = null
  }

  gsap.fromTo(topHeaderRef.value,
    {
      y: '100vh',
      opacity: 0 // 恢复初始透明度为0，让它在屏幕最底部时是隐形的
    },
    {
      y: 0,
      opacity: 1, // 伴随飞入的过程逐渐完全显示
      duration: 1.4,
      ease: 'power4.out',
      delay: 0,
      clearProps: 'transform',
      onComplete: () => {
        // 动画完成时，强制把 style 的 opacity 移除，防止被内联样式锁死
        if (topHeaderRef.value) {
          topHeaderRef.value.style.opacity = ''
        }
        // 进场动画完毕后，再将滚动消失动画挂载到 ScrollTrigger
        if (topHeaderTween) {
          ScrollTrigger.create({
            animation: topHeaderTween,
            start: 0,
            end: 200,
            scrub: true,
          })
          ScrollTrigger.refresh()
        }
      }
    })
}

// 监听自定义事件，当首页的 Hero 动画完成或到达特定阶段时触发导航栏入场
const handleHeroReady = () => {
  playHeaderIntro()
}

onMounted(() => {
  // 顶部导航在页面刚开始滚动的前 200px 内逐渐上移并隐藏。
  topHeaderTween = gsap.to(topHeaderRef.value, {
    yPercent: -140,
    autoAlpha: 0,
    ease: 'none',
    paused: true, // 初始不执行，等进场动画完毕再绑定到 ScrollTrigger
  })

  // 底部导航默认藏在视口下方，只有滚动到深处并向上滚时才出现。
  gsap.set(bottomHeaderRef.value, {
    xPercent: -50,
    yPercent: 150,
    autoAlpha: 0,
    force3D: true
  })

  bottomHeaderScrollTrigger = ScrollTrigger.create({
    start: 0,
    end: 'max',
    onUpdate: (self) => {
      const scrollY = self.scroll()

      // 深度超过 1000px 后向上滚，显示底部导航。
      if (scrollY > 1000 && self.direction === -1) {
        setBottomHeaderVisible(true)
        return
      }

      // 回到 1000px 以内，或继续向下滚时，底部导航收回。
      if (scrollY <= 1000 || self.direction === 1) {
        setBottomHeaderVisible(false)
      }
    },
  })

  ScrollTrigger.refresh()
})

// 监听全局加载状态，当加载完成后再决定 Header 的进场时机
watch(() => appStore.isAppLoading, (isLoading) => {
  if (!isLoading && typeof window !== 'undefined') {
    if (route.path === '/') {
      // 首页：等待自定义事件
      window.addEventListener('hero-intro-done', handleHeroReady, { once: true })

      // 增加一个保底的 setTimeout，防止首页的动画事件因为某种原因未能触发
      // 从 loading 结束开始算起，首页的 intro 和 hero 动画加起来大约 3~4 秒
      fallbackTimer = setTimeout(() => {
        window.removeEventListener('hero-intro-done', handleHeroReady)
        playHeaderIntro()
      }, 5000)
    } else {
      // 非首页：加载完成后直接进场
      playHeaderIntro()
    }
  }
}, { immediate: true })

onBeforeUnmount(() => {
    if (fallbackTimer) {
      clearTimeout(fallbackTimer)
      fallbackTimer = null
    }
    if (typeof window !== 'undefined') {
      window.removeEventListener('hero-intro-done', handleHeroReady)
    }
    topHeaderTween?.scrollTrigger?.kill()
    topHeaderTween?.kill()
    bottomHeaderScrollTrigger?.kill()
    topHeaderTween = null
    bottomHeaderScrollTrigger = null
    isBottomHeaderVisible = false
    if (topHeaderRef.value && bottomHeaderRef.value) {
      gsap.killTweensOf([topHeaderRef.value, bottomHeaderRef.value])
    }
  })
</script>

<template>
  <header ref="topHeaderRef"
    class="site-header-top fixed left-0 right-0 top-0 z-50 mx-auto flex h-[100px] w-page-container max-w-[calc(100%-2rem)] items-center justify-between px-4 py-5"
    style="opacity: 0; transform: translateY(100vh);">
    <!-- 左侧：Logo 和 标题 -->
    <AppLogo />

    <!-- 中间：导航链接 -->
    <nav class="hidden md:flex items-center gap-10 lg:gap-16">
      <NuxtLink v-for="item in navItems" :key="item.name" :to="item.path"
        class="nav-link-item group flex items-center overflow-hidden font-semibold tracking-[-0.7px] text-black"
        style="font-size: 1rem; justify-content: flex-start; position: relative;">
        <div
          class="flex items-center transition-transform duration-300 group-hover:translate-x-0 -translate-x-[18px] pr-[18px]">
          <span class="mr-2 h-2.5 w-2.5 rounded-full bg-black shrink-0"></span>
          <span>{{ item.name }}</span>
        </div>
      </NuxtLink>
    </nav>

    <!-- 右侧：菜单图标 (使用 div 绘制) -->
    <div class="menu-icon group flex h-12 w-12 cursor-pointer flex-col items-end justify-center gap-[8px]">
      <div class="h-[2px] w-10 bg-black transition-all duration-300 group-hover:translate-y-[2.5px]"></div>
      <div class="h-[2px] w-10 bg-black transition-all duration-300 group-hover:-translate-y-[2.5px]"></div>
    </div>
  </header>

  <header ref="bottomHeaderRef" class="site-header-bottom z-50 bg-white/80 backdrop-blur-md">
    <!-- 左侧菜单 (前两个菜单项) -->
    <nav class="flex items-center">
      <NuxtLink v-for="item in navItems.slice(0, 2)" :key="'bottom-' + item.name" :to="item.path"
        class="group flex items-center overflow-hidden font-semibold tracking-[-0.7px] text-black"
        style="font-size: 1rem; justify-content: flex-start; position: relative;">
        <div
          class="flex items-center transition-transform duration-300 group-hover:translate-x-0 -translate-x-[18px] pr-[18px]">
          <span class="mr-2 h-2.5 w-2.5 rounded-full bg-black shrink-0"></span>
          <span>{{ item.name }}</span>
        </div>
      </NuxtLink>
    </nav>

    <!-- 中间 Logo (组件内部自带跳转和动画) -->
    <div class="flex items-center justify-center">
      <AppLogo compact click-action="top" />
    </div>

    <!-- 右侧菜单 (中间两个菜单项，留最后一个 contact 给右上角按钮) -->
    <nav class="flex items-center justify-self-end">
      <NuxtLink v-for="item in navItems.slice(2, 4)" :key="'bottom-' + item.name" :to="item.path"
        class="group flex items-center overflow-hidden font-semibold tracking-[-0.7px] text-black"
        style="font-size: 1rem; justify-content: flex-start; position: relative;">
        <div
          class="flex items-center transition-transform duration-300 group-hover:translate-x-0 -translate-x-[18px] pr-[18px]">
          <span class="mr-2 h-2.5 w-2.5 rounded-full bg-black shrink-0"></span>
          <span>{{ item.name }}</span>
        </div>
      </NuxtLink>
    </nav>
  </header>
</template>

<style scoped>
.site-header-bottom {
  border: 1px solid #ffffff47;
  border-radius: 12px;
  grid-template-rows: auto;
  grid-template-columns: auto minmax(50px, auto) auto;
  grid-auto-columns: 1fr;
  place-items: center stretch;
  max-width: 570px;
  width: fit-content;
  padding: 15px 20px;
  display: grid;
  position: fixed;
  left: 50%;
  bottom: 15px;
  overflow: hidden;
  visibility: hidden;
  opacity: 0;
  box-shadow: 0 -1px #0000001f, 0 12px 30px #0000001a, inset 0 1px #ffffff96;
}
</style>
