import { cookies } from "next/headers";
import { NextResponse } from "next/server";

import {
  ACCESS_TOKEN,
  AUTH_USER_ID,
  CLAIM_NAME,
  COOKIE_DOMAIN,
  REFRESH_TOKEN,
  SERVER_API_URL,
  SITE_ID,
} from "@/shared/config";

async function handler(
  request: Request,
  params: { url: string[] },
  method: "GET" | "POST" | "PUT" | "DELETE",
) {
  const cookieStore = await cookies();
  const headers: Record<string, string> = {
    "Content-Type": "application/json",
    "X-Site-Id": SITE_ID,
  };
  const deviceId = request.headers.get("X-Device-Id");
  if (deviceId) {
    headers["X-Device-Id"] = deviceId;
  }
  let body = {};
  const isRefreshHandler = params.url.includes("refresh");

  // silent refresh
  if (isRefreshHandler) {
    const refreshToken = cookieStore.get(REFRESH_TOKEN);
    headers[CLAIM_NAME] = refreshToken?.value ?? "";

    if (!headers[CLAIM_NAME]) {
      return NextResponse.json({ message: "Can't refresh" }, { status: 401 });
    }
  }

  try {
    if (!isRefreshHandler) {
      body = await request.json();
    }

    const targetUrl = `${SERVER_API_URL}/${params.url.join("/")}`;
    const result = await fetch(targetUrl, {
      method,
      headers,
      body: JSON.stringify(body),
    });

    if (!result.ok) {
      return NextResponse.json({ message: "Invalid Credentials" }, { status: 401 });
    }

    const accessToken = result.headers.get(ACCESS_TOKEN);
    const refreshToken = result.headers.get(REFRESH_TOKEN);
    const userId = result.headers.get(AUTH_USER_ID);

    if (accessToken && userId) {
      const response = NextResponse.json({
        [ACCESS_TOKEN]: accessToken,
        [AUTH_USER_ID]: userId,
      });

      if (refreshToken) {
        cookieStore.set(REFRESH_TOKEN, refreshToken, {
          httpOnly: true,
          sameSite: "strict",
          domain: COOKIE_DOMAIN,
          path: "/",
        });
      }

      return response;
    }

    return NextResponse.json({ message: "Invalid Credentials" }, { status: 401 });
  } catch (error) {
    console.error(`[Proxy API] Error caught in handler:`, error);
    return NextResponse.json({ message: "Server Error", error }, { status: 500 });
  }
}

export async function POST(request: Request, props: { params: Promise<{ url: string[] }> }) {
  const params = await props.params;
  return handler(request, params, "POST");
}

export async function PUT(request: Request, props: { params: Promise<{ url: string[] }> }) {
  const params = await props.params;
  return handler(request, params, "PUT");
}