import { useQuery } from "@tanstack/react-query";
import { Link, useRoute } from "wouter";
import { ArrowLeft, Play, Clock, Youtube } from "lucide-react";
import Header from "@/components/header";
import Footer from "@/components/footer";
import { PageSideAds, TopBannerAd, MultiplexAd } from "@/components/adsense";
import { Skeleton } from "@/components/ui/skeleton";
import { format } from "date-fns";
import { de } from "date-fns/locale";

export interface YtVideo {
  ytId: string;
  slug: string;
  title: string;
  shortTitle: string;
  rubrik: string;
  publishedAt: string;
  durationS: number;
  teaser: string;
  description: string;
  chapters: { t: string; label: string }[];
  tags: string[];
  previewUrl: string;
  previewS: number;
  posterUrl: string;
  youtubeUrl: string;
}

export function dauer(s: number) {
  const m = Math.floor(s / 60);
  const r = s % 60;
  return `${m}:${String(r).padStart(2, "0")}`;
}

function RelatedCard({ v }: { v: YtVideo }) {
  return (
    <Link href={`/video/${v.slug}`}>
      <article className="group cursor-pointer bg-card rounded-md border border-card-border h-full flex flex-col" data-testid={`card-related-${v.ytId}`}>
        <div className="relative overflow-hidden rounded-t-md">
          <img src={v.posterUrl} alt={v.shortTitle} loading="lazy"
               className="w-full aspect-video object-cover transition-transform duration-500 group-hover:scale-105" />
          <span className="absolute bottom-2 right-2 rounded bg-black/75 px-1.5 py-0.5 text-[11px] font-medium text-white">
            {dauer(v.durationS)}
          </span>
        </div>
        <div className="p-3">
          <h3 className="text-sm font-semibold leading-snug line-clamp-2 text-card-foreground group-hover:text-primary transition-colors">
            {v.shortTitle}
          </h3>
        </div>
      </article>
    </Link>
  );
}

export default function VideoDetailPage() {
  const [, params] = useRoute("/video/:slug");
  const slug = params?.slug || "";
  const { data, isLoading } = useQuery<{ item: YtVideo; related: YtVideo[] }>({
    queryKey: [`/api/yt-videos/${slug}`],
    enabled: !!slug,
  });
  const v = data?.item;

  return (
    <div className="min-h-screen bg-background">
      <Header />
      <PageSideAds />
      <main className="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-4">
        <TopBannerAd />
        <Link href="/videos">
          <button className="flex items-center gap-2 text-muted-foreground hover:text-foreground transition-colors mb-5 text-sm" data-testid="button-back-videos">
            <ArrowLeft className="w-4 h-4" />
            Alle Videos
          </button>
        </Link>

        {isLoading || !v ? (
          <div className="space-y-4">
            <Skeleton className="w-full aspect-video rounded-lg" />
            <Skeleton className="h-7 w-3/4" />
            <Skeleton className="h-4 w-full" />
          </div>
        ) : (
          <>
            <div className="rounded-lg overflow-hidden bg-black">
              <video
                controls
                playsInline
                preload="metadata"
                poster={v.posterUrl}
                src={v.previewUrl}
                className="w-full aspect-video"
                data-testid="video-preview"
              />
            </div>

            <div className="mt-3 flex flex-wrap items-center gap-x-3 gap-y-2 text-xs text-muted-foreground">
              <span className="rounded bg-primary/10 px-2 py-1 font-semibold text-primary">{v.rubrik}</span>
              <span className="flex items-center gap-1"><Clock className="w-3.5 h-3.5" />{dauer(v.durationS)}</span>
              <span>{format(new Date(v.publishedAt), "d. MMMM yyyy", { locale: de })}</span>
              <span className="text-muted-foreground/70">Vorschau {v.previewS} Sek.</span>
            </div>

            <h1 className="mt-3 text-2xl sm:text-3xl font-bold text-foreground leading-tight" data-testid="text-video-title">
              {v.shortTitle}
            </h1>

            {v.teaser && (
              <p className="mt-3 text-base text-card-foreground leading-relaxed" data-testid="text-video-teaser">
                {v.teaser}
              </p>
            )}

            <a
              href={v.youtubeUrl}
              target="_blank"
              rel="noopener"
              className="mt-5 inline-flex w-full sm:w-auto items-center justify-center gap-2 rounded-md bg-primary px-6 py-3 text-base font-semibold text-primary-foreground hover:opacity-90"
              data-testid="link-watch-youtube"
            >
              <Youtube className="w-5 h-5" />
              Ganzes Video auf YouTube ansehen
            </a>

            {v.chapters?.length > 0 && (
              <section className="mt-8">
                <h2 className="text-lg font-bold text-foreground mb-3">Kapitel</h2>
                <ul className="space-y-1.5">
                  {v.chapters.map((c) => (
                    <li key={c.t} className="text-sm">
                      <span className="inline-block w-14 font-mono text-primary">{c.t}</span>
                      <span className="text-card-foreground">{c.label}</span>
                    </li>
                  ))}
                </ul>
              </section>
            )}

            {v.description && (
              <section className="mt-8">
                <h2 className="text-lg font-bold text-foreground mb-2">Zum Video</h2>
                <p className="whitespace-pre-line text-sm text-muted-foreground leading-relaxed">
                  {v.description.replace(/\n{3,}/g, "\n\n")}
                </p>
              </section>
            )}

            <MultiplexAd />

            {data?.related?.length ? (
              <section className="mt-10">
                <h2 className="text-lg font-bold text-foreground mb-4">Mehr aus {v.rubrik}</h2>
                <div className="grid grid-cols-2 md:grid-cols-4 gap-4">
                  {data.related.map((r) => <RelatedCard key={r.ytId} v={r} />)}
                </div>
              </section>
            ) : null}
          </>
        )}
      </main>
      <Footer />
    </div>
  );
}