import { NextResponse } from "next/server";

export const runtime = "nodejs";

// RAG never goes through api-gateway. The gateway proxies `/auth/*` only --
// apps/api-gateway/src/proxy/ holds a single AuthProxyController -- so
// preferring AI_SERVICE_URL here pointed every RAG call at a service with no
// such route the moment apiGateway was enabled, breaking chat, suggest,
// history, sections, section-text and feedback at once. Resolve ai-service
// directly and let AI_SERVICE_URL mean what its name says: auth only.
const AI_SERVICE_URL = process.env.AI_SERVICE_URL ?? "http://localhost:8000";

export async function GET(request: Request) {
  const { searchParams } = new URL(request.url);
  const q = searchParams.get("q")?.trim() || "";

  if (!q) {
    return NextResponse.json({ suggestions: [] });
  }

  try {
    const targetUrl = AI_SERVICE_URL.includes("/v1/rag")
      ? `${AI_SERVICE_URL.replace(/\/query$/, "/suggest")}?q=${encodeURIComponent(q)}`
      : `${AI_SERVICE_URL}/v1/rag/suggest?q=${encodeURIComponent(q)}`;

    const upstream = await fetch(targetUrl, {
      method: "GET",
      headers: {
        "X-Client-Version": "1.0.0",
      },
      cache: "no-store",
    });

    if (!upstream.ok) {
      return NextResponse.json({ suggestions: [] });
    }

    const data = await upstream.json();
    return NextResponse.json(data);
  } catch {
    return NextResponse.json({ suggestions: [] });
  }
}