'use client';
import type { DNAResponse, SearchResponse, SeriesResponse, SimilarResponse } from './types';

/**
 * Browser-side fetch helpers: same-origin `/api/v1/*` (rewritten by next.config.ts to the FastAPI service).
 * Kept deliberately small — server components should do the heavy lifting.
 */
export class ClientApiError extends Error {
  constructor(
    readonly status: number,
    message: string,
  ) {
    super(message);
    this.name = 'ClientApiError';
  }
}

async function get<T>(path: string, signal?: AbortSignal): Promise<T> {
  const res = await fetch(`/api/v1${path}`, { headers: { accept: 'application/json' }, signal });
  if (!res.ok) throw new ClientApiError(res.status, `API ${res.status}`);
  return (await res.json()) as T;
}

export const clientApi = {
  search: (q: string, limit = 12, signal?: AbortSignal) =>
    get<SearchResponse>(`/search?q=${encodeURIComponent(q)}&limit=${limit}`, signal),
  countrySeries: (id: string, indicator: string, signal?: AbortSignal) =>
    get<SeriesResponse>(`/countries/${encodeURIComponent(id)}/series/${encodeURIComponent(indicator)}`, signal),
  countrySimilar: (id: string, mode: string, signal?: AbortSignal) =>
    get<SimilarResponse>(`/countries/${encodeURIComponent(id)}/similar?mode=${encodeURIComponent(mode)}`, signal),
  countryDna: (id: string, reference: string, signal?: AbortSignal) =>
    get<DNAResponse>(`/countries/${encodeURIComponent(id)}/dna?reference=${encodeURIComponent(reference)}`, signal),
};