import type { ApiCtx, Next, ApiRequest } from './types';
import { createPipe } from './pipe';
import type { SagaApi } from './pipe';
import type { ApiName, SagaQueryApi } from './api-types';

/**
 * Creates a middleware pipeline for HTTP requests.
 *
 * @remarks
 * It uses {@link createPipe} under the hood.
 *
 * @example
 * ```ts
 * import { createApi, requestMonitor, fetcher } from 'saga-query';
 *
 * const api = createApi();
 * api.use(requestMonitor());
 * api.use(api.routes());
 * api.use(fetcher({ baseUrl: 'https://api.com' }));
 *
 * const fetchUsers = api.get('/users', function*(ctx, next) {
 *   yield next();
 * });
 *
 * store.dispatch(fetchUsers());
 * ```
 */
export function createApi<Ctx extends ApiCtx = ApiCtx>(
  basePipe?: SagaApi<Ctx>,
): SagaQueryApi<Ctx> {
  const pipe = basePipe || createPipe<Ctx>();
  const uri = (prename: ApiName) => {
    const create = pipe.create as any;

    let name = prename;
    let remainder = '';
    if (Array.isArray(name)) {
      if (name.length === 0) {
        throw new Error(
          'createApi requires a non-empty array for the name of the endpoint',
        );
      }
      name = prename[0];
      if (name.length > 1) {
        const [_, ...other] = prename;
        remainder = ` ${other.join('|')}`;
      }
    }
    const tmpl = (method: string) => `${name} [${method}]${remainder}`;

    return {
      get: (...args: any[]) => create(tmpl('GET'), ...args),
      post: (...args: any[]) => create(tmpl('POST'), ...args),
      put: (...args: any[]) => create(tmpl('PUT'), ...args),
      patch: (...args: any[]) => create(tmpl('PATCH'), ...args),
      delete: (...args: any[]) => create(tmpl('DELETE'), ...args),
      options: (...args: any[]) => create(tmpl('OPTIONS'), ...args),
      head: (...args: any[]) => create(tmpl('HEAD'), ...args),
      connect: (...args: any[]) => create(tmpl('CONNECT'), ...args),
      trace: (...args: any[]) => create(tmpl('TRACE'), ...args),
    };
  };

  return {
    use: pipe.use,
    saga: pipe.saga,
    create: pipe.create,
    routes: pipe.routes,
    cache: () => {
      return function* onCache(ctx: Ctx, next: Next) {
        ctx.cache = true;
        yield next();
      };
    },
    request: (req: ApiRequest) => {
      return function* onRequest(ctx: Ctx, next: Next) {
        ctx.request = ctx.req(req);
        yield next();
      };
    },
    uri,
    get: (name: ApiName, ...args: any[]) => uri(name).get(...args),
    post: (name: ApiName, ...args: any[]) => uri(name).post(...args),
    put: (name: ApiName, ...args: any[]) => uri(name).put(...args),
    patch: (name: ApiName, ...args: any[]) => uri(name).patch(...args),
    delete: (name: ApiName, ...args: any[]) => uri(name).delete(...args),
    options: (name: ApiName, ...args: any[]) => uri(name).options(...args),
    head: (name: ApiName, ...args: any[]) => uri(name).head(...args),
    connect: (name: ApiName, ...args: any[]) => uri(name).connect(...args),
    trace: (name: ApiName, ...args: any[]) => uri(name).trace(...args),
  };
}