import { type NextRequest, NextResponse } from "next/server";
import {
  getPublicChangelogEvents,
  getEnabledAiModelsWithProvider,
  getNavLinks,
  getPublicFeaturedImages,
  getPublicFeaturedRanking,
  getSiteSettings,
  getTutorialVideos,
} from "@/lib/db/queries";

function formatProviderStats(models: Awaited<ReturnType<typeof getEnabledAiModelsWithProvider>>) {
  const providerMap = new Map<string, number>();

  for (const item of models) {
    const providerName = item.provider.name;
    providerMap.set(providerName, (providerMap.get(providerName) ?? 0) + 1);
  }

  return Array.from(providerMap.entries()).map(([name, count]) => ({ name, count }));
}

export async function GET(request: NextRequest) {
  try {
    const view = request.nextUrl.searchParams.get("view") || "home";

    const [settings, navLinks, models, videos] = await Promise.all([
      getSiteSettings(),
      getNavLinks(),
      getEnabledAiModelsWithProvider(),
      getTutorialVideos(),
    ]);

    if (view === "pricing") {
      const featuredImages = await getPublicFeaturedImages(8);

      const response = NextResponse.json({
        view,
        settings,
        pricing: {
          models: models.length,
          tutorials: videos.length,
          featuredSamples: featuredImages,
        },
      });

      response.headers.set("Cache-Control", "public, s-maxage=60, stale-while-revalidate=300");
      return response;
    }

    if (view === "news") {
      const [featuredImages, ranking] = await Promise.all([
        getPublicFeaturedImages(12),
        settings.rankingEnabled ? getPublicFeaturedRanking(6) : Promise.resolve([]),
      ]);

      const response = NextResponse.json({
        view,
        settings,
        news: {
          videos,
          featuredImages,
          ranking,
        },
      });

      response.headers.set("Cache-Control", "public, s-maxage=60, stale-while-revalidate=300");
      return response;
    }

    if (view === "blog") {
      const featuredImages = await getPublicFeaturedImages(8);

      const response = NextResponse.json({
        view,
        settings,
        blog: {
          videos,
          featuredImages,
        },
      });

      response.headers.set("Cache-Control", "public, s-maxage=60, stale-while-revalidate=300");
      return response;
    }

    if (view === "changelog") {
      const [events, ranking] = await Promise.all([
        getPublicChangelogEvents(18),
        settings.rankingEnabled ? getPublicFeaturedRanking(6) : Promise.resolve([]),
      ]);

      const response = NextResponse.json({
        view,
        settings,
        changelog: {
          events,
          ranking,
        },
      });

      response.headers.set("Cache-Control", "public, s-maxage=60, stale-while-revalidate=300");
      return response;
    }

    const [featuredImages, ranking] = await Promise.all([
      getPublicFeaturedImages(12),
      settings.rankingEnabled ? getPublicFeaturedRanking(5) : Promise.resolve([]),
    ]);

    const response = NextResponse.json({
      view: "home",
      settings,
      navLinks,
      providers: formatProviderStats(models),
      stats: {
        modelCount: models.length,
        tutorialCount: videos.length,
        featuredCount: featuredImages.length,
      },
      featuredImages,
      ranking,
      videos: settings.tutorialEnabled ? videos : [],
    });

    response.headers.set("Cache-Control", "public, s-maxage=60, stale-while-revalidate=300");
    return response;
  } catch (error) {
    console.error("[Public Lovart API] Error:", error);
    return NextResponse.json({ error: "Failed to fetch Lovart public payload" }, { status: 500 });
  }
}