const rawApiBase = (import.meta.env.VITE_API_BASE ?? '').trim();

export const API_BASE = rawApiBase.replace(/\/+$/, '');

export function apiUrl(path: string) {
  if (!path) return API_BASE || '';
  if (/^https?:\/\//i.test(path) || path.startsWith('data:') || path.startsWith('blob:')) {
    return path;
  }
  const normalizedPath = path.startsWith('/') ? path : `/${path}`;
  return `${API_BASE}${normalizedPath}`;
}

export function apiEventSource(path: string) {
  return new EventSource(apiUrl(path));
}

export async function readApiError(res: Response) {
  const text = await res.text().catch(() => '');
  if (!text) return `${res.status} ${res.statusText}`.trim();
  try {
    const parsed = JSON.parse(text);
    return parsed.detail || parsed.message || text;
  } catch {
    return text;
  }
}

export async function ensureOk(res: Response, fallback: string) {
  if (res.ok) return res;
  const detail = await readApiError(res);
  throw new Error(`${fallback} (${res.status})${detail ? `: ${detail}` : ''}`);
}