import { NextResponse } from "next/server";

const IMGW_HYBRID_URL = "https://meteo.imgw.pl/api/v1/forecast/fcapi";
// This browser token is published by the official meteo.imgw.pl frontend.
const IMGW_HYBRID_TOKEN = "p4DXKjsYadfBV21TYrDk";

function parseCoordinate(value: string | null, min: number, max: number) {
  if (!value?.trim()) return null;
  const coordinate = Number(value);
  return Number.isFinite(coordinate) && coordinate >= min && coordinate <= max ? coordinate : null;
}

export async function GET(request: Request) {
  const { searchParams } = new URL(request.url);
  const latitude = parseCoordinate(searchParams.get("latitude"), -90, 90);
  const longitude = parseCoordinate(searchParams.get("longitude"), -180, 180);
  if (latitude === null || longitude === null) {
    return NextResponse.json({ error: "Invalid coordinates." }, { status: 400 });
  }

  const params = new URLSearchParams({
    token: IMGW_HYBRID_TOKEN,
    lat: String(latitude),
    lon: String(longitude),
    m: "hybrid",
  });

  try {
    const response = await fetch(`${IMGW_HYBRID_URL}?${params}`, { next: { revalidate: 120 } });
    if (!response.ok) return NextResponse.json({ error: "IMGW Hybrid service is unavailable." }, { status: 502 });
    return NextResponse.json(await response.json(), {
      headers: { "Cache-Control": "public, s-maxage=120, stale-while-revalidate=300" },
    });
  } catch {
    return NextResponse.json({ error: "IMGW Hybrid service is unavailable." }, { status: 502 });
  }
}