import arrayifyStream from 'arrayify-stream';
import streamifyArray from 'streamify-array';
import { HeadOperationHandler } from '../../../../src/ldp/operations/HeadOperationHandler';
import type { Operation } from '../../../../src/ldp/operations/Operation';
import type { Representation } from '../../../../src/ldp/representation/Representation';
import type { ResourceStore } from '../../../../src/storage/ResourceStore';
import { UnsupportedHttpError } from '../../../../src/util/errors/UnsupportedHttpError';

describe('A HeadOperationHandler', (): void => {
  const store = {
    getRepresentation: async(): Promise<Representation> => ({ binary: false, data: streamifyArray([ 1, 2, 3 ]) } as
      Representation),
  } as unknown as ResourceStore;
  const handler = new HeadOperationHandler(store);

  it('only supports HEAD operations.', async(): Promise<void> => {
    await expect(handler.canHandle({ method: 'HEAD' } as Operation)).resolves.toBeUndefined();
    await expect(handler.canHandle({ method: 'GET' } as Operation)).rejects.toThrow(UnsupportedHttpError);
    await expect(handler.canHandle({ method: 'POST' } as Operation)).rejects.toThrow(UnsupportedHttpError);
  });

  it('returns the representation from the store with the input identifier and empty data.', async(): Promise<void> => {
    const result = await handler.handle({ target: { path: 'url' }} as Operation);
    expect(result.identifier.path).toBe('url');
    expect(result.body?.binary).toBe(false);
    await expect(arrayifyStream(result.body!.data)).resolves.toEqual([]);
  });
});