import { NextRequest } from "next/server";

export const dynamic = "force-dynamic";
export const runtime = "nodejs";

const AGENT_BACKEND_BASE_URL =
  process.env.AGENT_API_INTERNAL_BASE_URL ??
  process.env.NEXT_PUBLIC_AGENT_API_BASE_URL ??
  "http://127.0.0.1:8787";

type RouteContext = {
  params: Promise<{ path?: string[] }>;
};

export async function GET(request: NextRequest, context: RouteContext) {
  return proxyAgentRequest(request, context);
}

export async function POST(request: NextRequest, context: RouteContext) {
  return proxyAgentRequest(request, context);
}

export async function PATCH(request: NextRequest, context: RouteContext) {
  return proxyAgentRequest(request, context);
}

export async function DELETE(request: NextRequest, context: RouteContext) {
  return proxyAgentRequest(request, context);
}

async function proxyAgentRequest(request: NextRequest, context: RouteContext) {
  const { path = [] } = await context.params;
  const upstreamUrl = new URL(`/api/v1/agent/chat/${path.map(encodeURIComponent).join("/")}`, AGENT_BACKEND_BASE_URL);
  upstreamUrl.search = request.nextUrl.search;

  const headers = new Headers(request.headers);
  headers.delete("host");
  headers.delete("content-length");

  const body = request.method === "GET" || request.method === "HEAD" ? undefined : request.body;
  const upstreamResponse = await fetch(upstreamUrl, {
    method: request.method,
    headers,
    body,
    cache: "no-store",
    duplex: body ? "half" : undefined
  } as RequestInit & { duplex?: "half" });

  const responseHeaders = new Headers(upstreamResponse.headers);
  responseHeaders.delete("content-encoding");
  responseHeaders.delete("content-length");

  return new Response(upstreamResponse.body, {
    status: upstreamResponse.status,
    statusText: upstreamResponse.statusText,
    headers: responseHeaders
  });
}