import type { ApiResult, HealthResponse, SessionDetailResponse } from './types';

export interface ApiClient {
  health(): Promise<ApiResult<HealthResponse>>;
  getSession(code: string): Promise<ApiResult<SessionDetailResponse>>;
}

export function createApiClient(baseUrl = '', fetchImpl: typeof fetch = fetch): ApiClient {
  async function request<T>(path: string): Promise<ApiResult<T>> {
    let response: Response;
    try {
      response = await fetchImpl(`${baseUrl}${path}`, {
        method: 'GET',
        headers: { Accept: 'application/json' }
      });
    } catch {
      return {
        ok: false,
        status: 0,
        error: { kind: 'network', status: 0, message: 'Network error while contacting API' }
      };
    }

    let payload: unknown;
    try {
      payload = await response.json();
    } catch {
      return {
        ok: false,
        status: response.status,
        error: { kind: 'parse', status: response.status, message: 'Invalid JSON response from API' }
      };
    }

    if (!response.ok) {
      return {
        ok: false,
        status: response.status,
        error: {
          kind: 'http',
          status: response.status,
          message: `HTTP ${response.status}`,
          payload
        }
      };
    }

    return { ok: true, status: response.status, data: payload as T };
  }

  return {
    health: () => request<HealthResponse>('/healthz'),
    getSession: (code: string) =>
      request<SessionDetailResponse>(`/lobby/sessions/${encodeURIComponent(code.trim().toUpperCase())}`)
  };
}