import { prisma } from "@/lib/prisma";
import BackButton from "@/app/components/BackButton";
import AwemeDetailClient from "./Client";
import type { Metadata } from "next";
import { getFileUrl } from "@/lib/minio";
import { AwemeData } from "./types";

export async function generateMetadata({ params }: { params: Promise<{ awemeId: string }> }): Promise<Metadata> {
  const id = (await params).awemeId;

  const [video, post] = await Promise.all([
    prisma.video.findUnique({
      where: { aweme_id: id },
      select: { desc: true, author: { select: { nickname: true } } },
    }),
    prisma.imagePost.findUnique({
      where: { aweme_id: id },
      select: { desc: true, author: { select: { nickname: true } } },
    })
  ]);

  const data = video || post;
  if (!data) {
    return {
      title: "作品不存在",
    };
  }

  const desc = data.desc || "查看作品详情";
  const author = data.author.nickname;
  const title = desc.length > 50 ? `${desc.slice(0, 50)}... - ${author}` : `${desc} - ${author}`;

  return {
    title,
    description: desc,
  };
}

export default async function AwemeDetail({ params }: { params: Promise<{ awemeId: string }> }) {
  const id = (await params).awemeId;

  const [video, post] = await Promise.all([
    prisma.video.findUnique({
      where: { aweme_id: id },
      include: { author: true },
    }),
    prisma.imagePost.findUnique({
      where: { aweme_id: id },
      include: { author: true, images: { orderBy: { order: "asc" } } },
    })
  ]);

  if (!video && !post) return <main className="p-8">找不到该作品</main>;

  const isVideo = !!video;

  // 获取评论总数
  const commentsCount = await prisma.comment.count({
    where: isVideo ? { videoId: id } : { imagePostId: id },
  });

  const aweme = isVideo ? video : post;

  const data: AwemeData = {
    aweme_id: aweme!.aweme_id,
    desc: aweme!.desc,
    created_at: aweme!.created_at,
    likesCount: Number(aweme!.digg_count),
    commentsCount,
    author: { nickname: aweme!.author.nickname, avatar_url: getFileUrl(aweme!.author.avatar_url || 'default-avatar.png') },
    ...(() => {
      if (isVideo) {
        const aweme = video!
        return {
          type: "video" as const,
          duration_ms: aweme!.duration_ms,
          video_url: aweme!.video_url,
          width: aweme!.width ?? null,
          height: aweme!.height ?? null,
        }
      } else {
        const aweme = post!
        return {
          type: "image" as const,
          images: aweme!.images.map(img => ({ ...img, url: getFileUrl(img.url) })),
          music_url: aweme!.music_url,
        };
      }
    })()
  }


  // Compute prev/next neighbors by created_at across videos and image posts
  const currentCreatedAt = (isVideo ? video!.created_at : post!.created_at);
  const [newerVideo, newerPost, olderVideo, olderPost] = await Promise.all([
    prisma.video.findFirst({ where: { created_at: { gt: currentCreatedAt } }, orderBy: { created_at: "asc" }, select: { aweme_id: true, created_at: true } }),
    prisma.imagePost.findFirst({ where: { created_at: { gt: currentCreatedAt } }, orderBy: { created_at: "asc" }, select: { aweme_id: true, created_at: true } }),
    prisma.video.findFirst({ where: { created_at: { lt: currentCreatedAt } }, orderBy: { created_at: "desc" }, select: { aweme_id: true, created_at: true } }),
    prisma.imagePost.findFirst({ where: { created_at: { lt: currentCreatedAt } }, orderBy: { created_at: "desc" }, select: { aweme_id: true, created_at: true } }),
  ]);
  const pickPrev = (() => {
    const cands: { aweme_id: string; created_at: Date }[] = [];
    if (newerVideo) cands.push({ aweme_id: newerVideo.aweme_id, created_at: newerVideo.created_at });
    if (newerPost) cands.push({ aweme_id: newerPost.aweme_id, created_at: newerPost.created_at });
    if (cands.length === 0) return null;
    cands.sort((a, b) => +a.created_at - +b.created_at);
    return { aweme_id: cands[0].aweme_id };
  })();
  const pickNext = (() => {
    const cands: { aweme_id: string; created_at: Date }[] = [];
    if (olderVideo) cands.push({ aweme_id: olderVideo.aweme_id, created_at: olderVideo.created_at });
    if (olderPost) cands.push({ aweme_id: olderPost.aweme_id, created_at: olderPost.created_at });
    if (cands.length === 0) return null;
    cands.sort((a, b) => +b.created_at - +a.created_at);
    return { aweme_id: cands[0].aweme_id };
  })();
  const neighbors: { prev: { aweme_id: string } | null; next: { aweme_id: string } | null } = { prev: pickPrev, next: pickNext };

  return (
    <main className="min-h-screen w-full overflow-hidden">
      {/* 顶部条改为悬浮在媒体区域之上，避免 sticky 造成 Y 方向滚动条 */}
      <div className="fixed left-3 top-3 z-30">
        <BackButton
          hrefFallback="/"
          className="inline-flex items-center justify-center w-9 h-9 rounded-full bg-white/15 text-white border border-white/20 backdrop-blur hover:bg-white/25"
        />
      </div>
      <AwemeDetailClient data={data} neighbors={neighbors} />
    </main>
  );
}

export const dynamic = "force-dynamic";
