import { NextRequest, NextResponse } from "next/server";
import { z } from "zod";
import { tmdbFetch, filterAdultMovies } from "@/lib/tmdb/client";
import { DISCOVER_CERT_PARAMS } from "@/lib/tmdb/certification";
import type { TMDBSearchResponse } from "@/types/tmdb";

const popularParamsSchema = z.object({
  page: z.coerce.number().int().min(1).max(500).optional().default(1),
});

export async function GET(request: NextRequest) {
  const rawParams = Object.fromEntries(request.nextUrl.searchParams);
  const parsed = popularParamsSchema.safeParse(rawParams);

  if (!parsed.success) {
    return NextResponse.json(
      { error: "Invalid parameters", details: parsed.error.flatten().fieldErrors },
      { status: 400 },
    );
  }

  const { page } = parsed.data;

  try {
    // Use /discover with sort_by=popularity.desc + cert filter so TMDB
    // pre-filters server-side; we still post-filter adult flags defensively.
    const data = await tmdbFetch<TMDBSearchResponse>("/discover/movie", {
      ...DISCOVER_CERT_PARAMS,
      sort_by: "popularity.desc",
      page: String(page),
    });

    return NextResponse.json(filterAdultMovies(data), {
      headers: { "Cache-Control": "public, s-maxage=300, stale-while-revalidate=60" },
    });
  } catch (error) {
    console.error("TMDB popular error:", error);
    return NextResponse.json({ error: "Failed to fetch popular movies" }, { status: 500 });
  }
}