import { NextRequest, NextResponse } from "next/server";
import {
  CLAIM_NAME,
  AUTH_USER_ID,
  PORT,
  PROXY_HOST,
  SERVER_API_URL,
  SITE_ID,
} from "./src/shared/config";

// 환경 변수 설정
const dcServiceUrl =
  process.env.NEXT_PUBLIC_DC_SERVICE_API_URL ?? "http://localhost:3000";

const serverApiUrl =
  process.env.NEXT_PUBLIC_SERVER_API_URL ?? "http://localhost:3000";

const flaskApiUrl =
  process.env.NEXT_PUBLIC_FLASK_API_URL ?? "http://localhost:5000";

const linkBackendApiHost = process.env.NEXT_PUBLIC_LINK_BACKEND_API_HOST ?? "http://localhost:8080";

// CSP 헤더 설정 함수 (img-src만)
function addSecurityHeaders(response: NextResponse): NextResponse {
  response.headers.set("Content-Security-Policy", "img-src 'self' data: https: blob:;");
  return response;
}

export function middleware(req: NextRequest) {
  const pathname = req.nextUrl.pathname;
  const searchParams = req.nextUrl.searchParams;

  const logMessages: string[] = [
    `[Middleware Request] ${new Date().toISOString()}`,
    `[Environment]\n  Mode: ${process.env.NODE_ENV}\n  Port: ${PORT}\n  Proxy Host: ${PROXY_HOST}\n  Server API URL: ${SERVER_API_URL}\n  Site ID: ${SITE_ID}\n  DC Service URL: ${dcServiceUrl}\n  Flask API URL: ${flaskApiUrl}\n  Link Backend API Host: ${linkBackendApiHost}`,
    `[Request]\n  Original Pathname: ${pathname}`,
  ];

  // DC Service 처리 (인증 토큰 포함)
  if (pathname.startsWith("/server/dc-service")) {
    const requestHeaders = new Headers(req.headers);
    const token = req.cookies.get(CLAIM_NAME)?.value;
    const userId = req.cookies.get(AUTH_USER_ID)?.value;
    
    const queryParams = searchParams.toString();
    const newUrl = `${dcServiceUrl}${pathname.replace("/server", "")}${
      queryParams ? `?${queryParams}` : ""
    }`;

    if (token) requestHeaders.set(CLAIM_NAME, token);
    if (userId) requestHeaders.set(AUTH_USER_ID, userId);
    
    // 디버깅을 위한 토큰 정보 로그
    logMessages.push(`  Token Debug: ${token ? 'EXISTS' : 'MISSING'}`);
    logMessages.push(`  UserId Debug: ${userId ? 'EXISTS' : 'MISSING'}`);
    logMessages.push(`  DC Service Rewritten URL: ${newUrl}`);
    logMessages.push("\n--------------------------------\n");
    console.log(logMessages.join("\n"));
    
    const response = NextResponse.rewrite(new URL(newUrl), {
      headers: requestHeaders,
    });
    return addSecurityHeaders(response);
  }

  // Flask Service 처리 (인증 토큰 포함)
  if (pathname.startsWith("/server/flask-service")) {
    const requestHeaders = new Headers(req.headers);
    const token = req.cookies.get(CLAIM_NAME)?.value;
    const userId = req.cookies.get(AUTH_USER_ID)?.value;
    
    const queryParams = searchParams.toString();
    const newUrl = `${flaskApiUrl}${pathname.replace("/server/flask-service", "")}${
      queryParams ? `?${queryParams}` : ""
    }`;

    if (token) requestHeaders.set(CLAIM_NAME, token);
    if (userId) requestHeaders.set(AUTH_USER_ID, userId);
    
    logMessages.push(`  Flask Service Rewritten URL: ${newUrl}`);
    logMessages.push("\n--------------------------------\n");
    console.log(logMessages.join("\n"));
    
    const response = NextResponse.rewrite(new URL(newUrl), {
      headers: requestHeaders,
    });
    return addSecurityHeaders(response);
  }

  // 일반 Server API 처리 (인증 토큰 포함)
  if (pathname.startsWith("/server") && !pathname.startsWith("/server/dc-service") && !pathname.startsWith("/server/flask-service")) {
    const requestHeaders = new Headers(req.headers);
    const token = req.cookies.get(CLAIM_NAME)?.value;
    const userId = req.cookies.get(AUTH_USER_ID)?.value;
    
    const queryParams = searchParams.toString();
    const newUrl = `${serverApiUrl}${pathname.replace("/server", "")}${
      queryParams ? `?${queryParams}` : ""
    }`;

    if (token) requestHeaders.set(CLAIM_NAME, token);
    if (userId) requestHeaders.set(AUTH_USER_ID, userId);
    
    logMessages.push(`  Server API Rewritten URL: ${newUrl}`);
    logMessages.push("\n--------------------------------\n");
    console.log(logMessages.join("\n"));
    
    const response = NextResponse.rewrite(new URL(newUrl), {
      headers: requestHeaders,
    });
    return addSecurityHeaders(response);
  }

  // Attach Service 처리 (인증 토큰 포함)
  if (pathname.startsWith("/attach-service")) {
    const requestHeaders = new Headers(req.headers);
    const token = req.cookies.get(CLAIM_NAME)?.value;
    const userId = req.cookies.get(AUTH_USER_ID)?.value;
    const newUrl = `${serverApiUrl}${pathname}`;

    if (token) requestHeaders.set(CLAIM_NAME, token);
    if (userId) requestHeaders.set(AUTH_USER_ID, userId);

    logMessages.push(`  Attach Service Rewritten URL: ${newUrl}`);
    logMessages.push("\n--------------------------------\n");
    console.log(logMessages.join("\n"));

    const response = NextResponse.rewrite(new URL(newUrl), {
      headers: requestHeaders,
    });
    return addSecurityHeaders(response);
  }

  // Link Backend API 처리 (인증 토큰 포함)
  if (pathname.startsWith("/api/link")) {
    const requestHeaders = new Headers(req.headers);
    const token = req.cookies.get(CLAIM_NAME)?.value;
    const userId = req.cookies.get(AUTH_USER_ID)?.value;
    
    // /api/link 경로를 제거하고 백엔드 API 경로로 변환
    const apiPath = pathname.replace("/api/link", "");
    const queryParams = searchParams.toString();
    const newUrl = `${linkBackendApiHost}${apiPath}${
      queryParams ? `?${queryParams}` : ""
    }`;

    if (token) requestHeaders.set(CLAIM_NAME, token);
    if (userId) requestHeaders.set(AUTH_USER_ID, userId);

    logMessages.push(`  Link API Rewritten URL: ${newUrl}`);
    logMessages.push("\n--------------------------------\n");
    console.log(logMessages.join("\n"));

    const response = NextResponse.rewrite(new URL(newUrl), {
      headers: requestHeaders,
    });
    return addSecurityHeaders(response);
  }

  // 루트 경로 리다이렉트
  if (pathname === "/") {
    const response = NextResponse.redirect(new URL("/category", req.url));
    return addSecurityHeaders(response);
  }

  logMessages.push("\n--------------------------------\n");
  console.log(logMessages.join("\n"));
  
  const response = NextResponse.next();
  return addSecurityHeaders(response);
}

export const config = {
  matcher: ["/server/:path*", "/attach-service/:path*", "/api/link/:path*", "/"],
};