import type { Metadata } from "next";
import { isCitedSite } from "yt-dlp-transcript-common/lib/siteSchema";
import { currentSite } from "../lib/site";
import { instanceMode } from "../lib/mode";
import { onlyReportView, readReportIndex, reportMetadata } from "../lib/reports";
import NewSinceLastVisit from "../components/NewSinceLastVisit";
import HubHome from "../components/hub/HubHome";
import ReportIndex from "../components/reports/ReportIndex";
import ReportArticle from "../components/reports/ReportArticle";

// A cited site with one report: the home page IS the report, so its tab names
// the report as the report's own page does. Every other home keeps the
// layout's default title (the site's).
export function generateMetadata(): Metadata {
  if (instanceMode() === "hub" || !isCitedSite(currentSite())) return {};
  const only = onlyReportView();
  return only ? reportMetadata(only) : {};
}

export default async function Home() {
  // Hub mode renders the federated shelf + cross-site search and reads no local
  // summaries manifest (there is none), so branch before countTranscripts().
  // The workspace layout passes hub children straight through, so <HubHome/>
  // stays fully self-contained (its own PlayerProvider + MultiSiteDataProvider).
  if (instanceMode() === "hub") {
    return <HubHome transcriptDownloads={currentSite().transcriptDownloads !== false} />;
  }

  const settings = currentSite();
  // A cited site publishes only its reports and their moments: its home is the
  // report index (a static export has no redirect to send it there), and it
  // has no summaries manifest, so countTranscripts() — which throws without
  // one — is never reached: its module is not even loaded on this path.
  //
  // With ONE published report the home page IS that report (the header then
  // links nothing: there is nowhere else to go). With more, the index -- no
  // heading of its own: the header already names the site.
  if (isCitedSite(settings)) {
    const only = onlyReportView();
    if (only) return <ReportArticle view={only} />;
    return <ReportIndex index={readReportIndex()} heading={null} tagline={settings.homeTagline} />;
  }
  const { countTranscripts } = await import("yt-dlp-transcript-common/lib/transcripts");
  const count = await countTranscripts();

  // The corpus data source, SearchSession, the persistent search bar, AND the
  // results pane all live in the workspace shell (layout → WorkspaceView). This
  // page renders only the results pane's INTRO chrome — the transcript-count
  // header — which the shell slots above the results.
  return (
    <div className="flex flex-col gap-6">
      <div className="flex flex-col gap-1">
        <h1 className="font-display text-3xl font-semibold tracking-tight text-foreground">
          <span className="tabular-nums">{count.toLocaleString()}</span>{" "}
          <span className="font-normal text-muted-foreground">transcripts</span>
        </h1>
        {settings.homeTagline && (
          <p className="text-sm text-muted-foreground">{settings.homeTagline}</p>
        )}
      </div>
      <NewSinceLastVisit siteId={settings.siteId} count={count} />
    </div>
  );
}