// app/api/options/lens/route.ts
import { NextResponse } from "next/server";
import { directusFetch } from "@/lib/directus";

/**
 * For fiber, co2-galvo, uv → f-theta scan lenses
 * For co2-gantry           → focusing lenses
 */
function collectionForTarget(target?: string): { coll: string } | null {
  switch (target) {
    case "settings_fiber":
    case "settings_co2gal":
    case "settings_uv":
      return { coll: "laser_scan_lens" };
    case "settings_co2gan":
      return { coll: "laser_focusing_lens" };
    default:
      return null;
  }
}

function bestLensLabel(it: any): string {
  // Try common fields, then derive something readable
  if (it.name) return String(it.name);
  if (it.model) return String(it.model);
  if (it.focal_length_mm) return `F${it.focal_length_mm} mm`;
  return String(it.submission_id ?? it.id ?? "lens");
}

export async function GET(req: Request) {
  try {
    const { searchParams } = new URL(req.url);
    const q      = searchParams.get("q")?.trim() || "";
    const limit  = Number(searchParams.get("limit") || "500");
    const target = searchParams.get("target") || undefined;

    const cfg = collectionForTarget(target);
    if (!cfg) return NextResponse.json({ error: "missing/invalid target" }, { status: 400 });

    const url = `/items/${cfg.coll}?limit=${limit}${q ? `&search=${encodeURIComponent(q)}` : ""}`;
    const { data } = await directusFetch<{ data: any[] }>(url);

    const out = (data || [])
    .map((it) => ({
      id: String(it.submission_id ?? it.id),
                  label: bestLensLabel(it),
    }))
    .sort((a, b) => a.label.localeCompare(b.label));

    return NextResponse.json({ data: out });
  } catch (e: any) {
    return NextResponse.json({ error: e?.message || "lens error" }, { status: 500 });
  }
}