// ABOUTME: Next.js middleware for page route protection.
// ABOUTME: Redirects unauthenticated users to login for protected pages.
import type { NextRequest } from "next/server";
import { NextResponse } from "next/server";

/**
 * Public paths that don't require authentication.
 */
const PUBLIC_PATHS = ["/login"];

/**
 * Paths to skip middleware entirely (API routes, static assets).
 */
const SKIP_PATHS = ["/api", "/_next", "/favicon.ico"];

/**
 * Checks if a request path should skip middleware.
 */
function shouldSkipMiddleware(pathname: string): boolean {
  return SKIP_PATHS.some((path) => pathname.startsWith(path));
}

/**
 * Checks if a request path is public (doesn't require auth).
 */
function isPublicPath(pathname: string): boolean {
  return PUBLIC_PATHS.some((path) => pathname === path);
}

/**
 * Next.js middleware function for page protection.
 * Checks for pb_auth cookie and redirects to login if missing.
 */
export async function middleware(request: NextRequest): Promise<NextResponse> {
  const { pathname } = request.nextUrl;

  // Skip middleware for API routes and static assets
  if (shouldSkipMiddleware(pathname)) {
    return NextResponse.next();
  }

  // Allow public paths without authentication
  if (isPublicPath(pathname)) {
    return NextResponse.next();
  }

  // Check for authentication cookie
  const authCookie = request.cookies.get("pb_auth");

  // If no valid auth cookie, redirect to login
  if (!authCookie || !authCookie.value) {
    const loginUrl = new URL("/login", request.nextUrl.origin);
    return NextResponse.redirect(loginUrl);
  }

  // User has auth cookie, allow through
  return NextResponse.next();
}

/**
 * Matcher configuration for Next.js middleware.
 * Matches all paths except static files and public assets.
 */
export const config = {
  matcher: [
    /*
     * Match all request paths except:
     * - _next/static (static files)
     * - _next/image (image optimization files)
     * - favicon.ico (favicon file)
     * - public folder
     */
    "/((?!_next/static|_next/image|favicon.ico|public).*)",
  ],
};