<template>
  <section class="page-section block w-full">
    <div class="max-w-[90rem] mx-auto w-full pt-20 md:pt-32 px-4 md:px-6 pb-12 md:pb-20">
      <button @click="$router.back()" class="mb-8 text-art-muted hover:text-art-text flex items-center gap-2 text-sm">
        <Icon name="arrow-left" :size="16" /> 返回
      </button>

      <div v-if="loading" class="flex justify-center py-20">
        <div class="animate-spin h-10 w-10 border-t-2 border-art-accent rounded-full" />
      </div>
      <div v-else-if="error" class="text-red-400 text-center py-12">
        <p class="mb-4">{{ error }}</p>
        <button
          type="button"
          class="px-4 py-2 border border-art-border rounded-full text-sm text-art-text hover:border-art-accent transition-colors"
          @click="load"
        >
          重试
        </button>
      </div>

      <template v-else-if="video">
        <h1 class="font-serif text-3xl md:text-4xl text-art-text mb-6">{{ video.title }}</h1>

        <!-- 播放区：未挂载前封面；挂载后 DPlayer + 暂停时大按钮遮罩 -->
        <div
          v-if="video.videoUrl"
          class="w-full aspect-video rounded-xl overflow-hidden bg-black mb-6 relative"
        >
          <!-- DPlayer 容器：playerReady 后始终保留，暂停不销毁 -->
          <div
            v-show="playerReady"
            ref="playerRef"
            class="absolute inset-0 w-full h-full"
          />

          <!-- 大播放按钮：初始 / 暂停时显示；点击开始或继续播 -->
          <div
            v-if="showPlayOverlay"
            class="absolute inset-0 z-20 cursor-pointer group"
            role="button"
            tabindex="0"
            aria-label="播放视频"
            @click="onOverlayPlay"
            @keydown.enter.prevent="onOverlayPlay"
            @keydown.space.prevent="onOverlayPlay"
          >
            <img
              v-if="!playerReady && coverSrc"
              :src="coverSrc"
              class="w-full h-full object-cover"
              alt=""
            />
            <div
              v-else-if="!playerReady"
              class="w-full h-full bg-black/60"
            />
            <div
              class="absolute inset-0 transition-colors"
              :class="playerReady ? 'bg-black/40' : 'bg-black/35 group-hover:bg-black/25'"
            />
            <div
              class="absolute top-1/2 left-1/2 -translate-x-1/2 -translate-y-1/2 w-20 h-20 md:w-24 md:h-24 rounded-full border border-white/40 bg-black/40 backdrop-blur-md flex items-center justify-center transition-transform group-hover:scale-105 group-active:scale-95 z-10"
            >
              <Icon name="play" :size="32" class="text-white ml-1" />
            </div>
          </div>
        </div>
        <div
          v-else
          class="w-full aspect-video rounded-xl overflow-hidden bg-black/40 border border-art-border flex items-center justify-center mb-6"
        >
          <p class="text-art-muted text-sm">暂无视频地址</p>
        </div>

        <!-- 专辑内前后导航：前 2 + 后 2 -->
        <div v-if="video.albumContext" class="mb-8">
          <div class="flex items-center justify-between mb-4">
            <p class="text-sm text-art-muted">
              来自专辑 <span class="text-art-text">{{ video.albumContext.albumName }}</span>
            </p>
            <router-link
              :to="`/videos/albums/${video.albumContext.albumId}`"
              class="text-xs text-art-accent hover:underline"
            >
              返回专辑
            </router-link>
          </div>
          <div class="flex gap-3 overflow-x-auto pb-2">
            <div
              v-for="pv in video.albumContext.prevVideos"
              :key="'prev-' + pv.id"
              class="shrink-0 w-36 cursor-pointer group"
              @click="router.push(`/videos/${pv.id}`)"
            >
              <div class="aspect-video rounded-lg overflow-hidden border border-art-border group-hover:border-art-accent/50 transition-colors bg-black/40">
                <img v-if="pv.cover" :src="pv.cover" class="w-full h-full object-cover opacity-80 group-hover:opacity-100" alt="" />
              </div>
              <p class="text-xs text-art-muted mt-1 line-clamp-2 group-hover:text-art-text">{{ pv.title }}</p>
            </div>
            <div class="shrink-0 w-36">
              <div class="aspect-video rounded-lg overflow-hidden border-2 border-art-accent bg-black/40">
                <img v-if="video.cover" :src="video.cover" class="w-full h-full object-cover" alt="" />
              </div>
              <p class="text-xs text-art-accent mt-1 line-clamp-2 font-medium">
                {{ playerReady && !showPlayOverlay ? '正在播放' : '当前视频' }}
              </p>
            </div>
            <div
              v-for="nv in video.albumContext.nextVideos"
              :key="'next-' + nv.id"
              class="shrink-0 w-36 cursor-pointer group"
              @click="router.push(`/videos/${nv.id}`)"
            >
              <div class="aspect-video rounded-lg overflow-hidden border border-art-border group-hover:border-art-accent/50 transition-colors bg-black/40">
                <img v-if="nv.cover" :src="nv.cover" class="w-full h-full object-cover opacity-80 group-hover:opacity-100" alt="" />
              </div>
              <p class="text-xs text-art-muted mt-1 line-clamp-2 group-hover:text-art-text">{{ nv.title }}</p>
            </div>
          </div>
        </div>

        <div class="max-w-3xl">
          <div class="flex gap-4 text-sm text-art-muted mb-4">
            <span v-if="video.categoryName">{{ video.categoryName }}</span>
            <span v-if="video.createdAt">发布于 {{ video.createdAt }}</span>
          </div>
          <p v-if="video.description" class="text-art-text/80 leading-relaxed whitespace-pre-wrap">{{ video.description }}</p>
        </div>
      </template>
    </div>
  </section>
</template>

<script setup lang="ts">
/**
 * 视频详情：封面大按钮点播；暂停时再次显示大按钮（不销毁播放器）。
 * 恢复 rounded-xl / rounded-lg 与 w-full，避免 PC 端观感变窄变生硬。
 */
import { ref, computed, onMounted, onBeforeUnmount, watch, nextTick } from 'vue'
import { useRoute, useRouter } from 'vue-router'
import DPlayer from 'dplayer'
import 'dplayer/dist/DPlayer.min.css'
import { fetchVideo, type VideoDetailItem } from '../services/api'
import Icon from '../components/Icon.vue'

const route = useRoute()
const router = useRouter()
const loading = ref(true)
const error = ref('')
const video = ref<VideoDetailItem | null>(null)
/** 已挂载 DPlayer */
const playerReady = ref(false)
/** 初始或暂停时显示大播放按钮 */
const showPlayOverlay = ref(true)
const playerRef = ref<HTMLElement | null>(null)
let dp: DPlayer | null = null

const coverSrc = computed(() => video.value?.poster || video.value?.cover || '')

/** 销毁 DPlayer，释放资源 */
function destroyPlayer() {
  if (dp) {
    dp.destroy()
    dp = null
  }
  playerReady.value = false
}

/** 绑定 play/pause，驱动大按钮显隐 */
function bindPlayerEvents(player: DPlayer) {
  player.on('play', () => {
    showPlayOverlay.value = false
  })
  player.on('pause', () => {
    showPlayOverlay.value = true
  })
}

/** 首次创建播放器并播放 */
async function initPlayer() {
  destroyPlayer()
  playerReady.value = true
  await nextTick()
  if (!playerRef.value || !video.value?.videoUrl) {
    playerReady.value = false
    return
  }
  dp = new DPlayer({
    container: playerRef.value,
    video: {
      url: video.value.videoUrl,
      pic: video.value.poster || video.value.cover,
    },
    autoplay: false,
    theme: '#d4b383',
    lang: 'zh-cn',
  })
  bindPlayerEvents(dp)
  try {
    dp.play()
    showPlayOverlay.value = false
  } catch {
    showPlayOverlay.value = true
  }
}

/**
 * 点击大按钮：未就绪则初始化；已就绪则继续 play。
 * 用户手势触发，利于移动端绕过自动播限制。
 */
async function onOverlayPlay() {
  if (!video.value?.videoUrl) return
  if (!playerReady.value || !dp) {
    showPlayOverlay.value = false
    await initPlayer()
    return
  }
  try {
    dp.play()
    showPlayOverlay.value = false
  } catch {
    showPlayOverlay.value = true
  }
}

/** 加载视频详情；切换条目时重置播放态 */
async function load() {
  loading.value = true
  error.value = ''
  showPlayOverlay.value = true
  destroyPlayer()
  try {
    video.value = await fetchVideo(route.params.id as string)
  } catch {
    error.value = '加载视频失败'
    video.value = null
  } finally {
    loading.value = false
  }
}

onMounted(load)
watch(() => route.params.id, load)
onBeforeUnmount(() => {
  destroyPlayer()
  showPlayOverlay.value = true
})
</script>

<style scoped>
:deep(.dplayer) {
  width: 100% !important;
  height: 100% !important;
}
</style>
