import { NextRequest, NextResponse } from "next/server";
import { PUBLIC_TO_UPSTREAM } from "@/lib/api-paths";

const API_BASE_URL = process.env.API_BASE_URL ?? "http://api-server:3000";

async function forward(
  request: NextRequest,
  path: string[],
): Promise<NextResponse> {
  const hash = path[0];
  const route = PUBLIC_TO_UPSTREAM[hash];
  if (!route) {
    return NextResponse.json({ error: "Not Found" }, { status: 404 });
  }
  const target = `${API_BASE_URL}/${route.upstream}${route.trailingSlash ? "/" : ""}`;

  const init: RequestInit = {
    method: request.method,
    headers: {
      "content-type":
        request.headers.get("content-type") ?? "application/json",
    },
  };
  if (request.method !== "GET" && request.method !== "HEAD") {
    init.body = await request.text();
  }

  try {
    const upstream = await fetch(target, init);
    const body = await upstream.text();
    return new NextResponse(body, {
      status: upstream.status,
      headers: {
        "content-type":
          upstream.headers.get("content-type") ?? "application/json",
      },
    });
  } catch (err) {
    return NextResponse.json({ error: String(err) }, { status: 500 });
  }
}

export async function GET(
  request: NextRequest,
  ctx: { params: Promise<{ path: string[] }> },
): Promise<NextResponse> {
  return forward(request, (await ctx.params).path);
}

export async function POST(
  request: NextRequest,
  ctx: { params: Promise<{ path: string[] }> },
): Promise<NextResponse> {
  return forward(request, (await ctx.params).path);
}