import 'server-only';
import { notFound } from 'next/navigation';

/**
 * Server-side API client. Server components talk to the FastAPI service directly (internal URL), never through the
 * browser rewrite. Every call is `no-store`: pages are dynamic and render the live state at request time.
 */
const BASE = process.env.API_URL_INTERNAL ?? process.env.API_URL ?? 'http://127.0.0.1:8352';

export class ApiError extends Error {
  constructor(
    public status: number,
    public path: string,
  ) {
    super(`API ${status} for ${path}`);
  }
}

export async function apiGet<T>(path: string, init?: { timeoutMs?: number }): Promise<T> {
  const ctrl = new AbortController();
  const timer = setTimeout(() => ctrl.abort(), init?.timeoutMs ?? 8000);
  try {
    const res = await fetch(BASE + path, { cache: 'no-store', signal: ctrl.signal, headers: { accept: 'application/json' } });
    if (res.status === 404) notFound();
    if (!res.ok) throw new ApiError(res.status, path);
    return (await res.json()) as T;
  } finally {
    clearTimeout(timer);
  }
}

/** Like apiGet but returns null instead of throwing when the API is unreachable/erroring (used for optional panels). */
export async function apiTry<T>(path: string): Promise<T | null> {
  try {
    return await apiGet<T>(path);
  } catch (e) {
    if (e && typeof e === 'object' && 'digest' in e && String((e as { digest?: string }).digest).startsWith('NEXT_HTTP_ERROR_FALLBACK')) throw e;
    return null;
  }
}