<template>
  <section class="page-section block">
    <div class="max-w-6xl mx-auto pb-12 md:pb-20">
      <button @click="$router.back()" class="mb-8 text-art-muted hover:text-white 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>
      <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-white/20 rounded-full text-sm text-white 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-white mb-6">{{ video.title }}</h1>

        <div
          v-if="video.videoUrl"
          ref="playerRef"
          class="w-full aspect-video rounded-xl overflow-hidden bg-black mb-6"
        ></div>
        <div
          v-else
          class="w-full aspect-video rounded-xl overflow-hidden bg-black/40 border border-white/10 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-white">{{ video.albumContext.albumName }}</span>
            </p>
            <router-link
              :to="`/videos/albums/${video.albumContext.albumId}`"
              class="text-xs text-art-accent hover:underline"
            >返回专辑</router-link>
          </div>
          <div class="flex gap-3 overflow-x-auto pb-2">
            <!-- 前序视频 -->
            <div
              v-for="pv in video.albumContext.prevVideos"
              :key="'prev-' + pv.id"
              class="shrink-0 w-36 cursor-pointer group"
              @click="router.push(`/videos/${pv.id}`)"
            >
              <div class="aspect-video rounded-lg overflow-hidden border border-white/10 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-white">{{ pv.title }}</p>
            </div>
            <!-- 当前视频高亮 -->
            <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">正在播放</p>
            </div>
            <!-- 后续视频 -->
            <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-white/10 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-white">{{ 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-white/80 leading-relaxed whitespace-pre-wrap">{{ video.description }}</p>
        </div>
      </template>
    </div>
  </section>
</template>

<script setup lang="ts">
import { ref, 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)
const playerRef = ref<HTMLElement | null>(null)
let dp: DPlayer | null = null

/** 销毁 DPlayer 实例 */
const destroyPlayer = () => {
  if (dp) { dp.destroy(); dp = null }
}

/** 创建 DPlayer 播放器 */
const initPlayer = async () => {
  destroyPlayer()
  if (!playerRef.value || !video.value?.videoUrl) return
  await nextTick()
  dp = new DPlayer({
    container: playerRef.value,
    video: { url: video.value.videoUrl, pic: video.value.poster || video.value.cover },
    theme: '#d4b383',
    lang: 'zh-cn',
  })
}

/** 加载视频详情 */
const load = async () => {
  loading.value = true
  error.value = ''
  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
  }
}

watch([video, playerRef, loading], async ([v, el, isLoading]) => {
  if (isLoading || !v?.videoUrl || !el) return
  await nextTick()
  initPlayer()
}, { flush: 'post' })

onMounted(load)
watch(() => route.params.id, load)
onBeforeUnmount(destroyPlayer)
</script>

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