import org.codelibs.fess.suggest.request.Response;

/**
 * <p>
 *   Deferred is a class that represents a deferred computation.
 *   It is similar to a Promise in JavaScript.
 *   It allows you to register callbacks that will be executed when the computation is complete,
 *   either successfully (resolve) or with an error (reject).
 * </p>
 *
 * <p>
 *   The Deferred class has a Promise inner class that allows you to register callbacks

    @Test
    public void test_promiseChaining_returnsSamePromise() throws Exception {
        final Deferred<SuggestResponse> deferred = new Deferred<>();

        Deferred<SuggestResponse>.Promise promise1 = deferred.promise();
        Deferred<SuggestResponse>.Promise promise2 = promise1.then(response -> {});
        Deferred<SuggestResponse>.Promise promise3 = promise2.error(error -> {});

     */
    public Deferred<T>.Promise execute(final Client client) {
        final String error = getValidationError();
        if (!Strings.isNullOrEmpty(error)) {
            throw new IllegalArgumentException(error);
        }

        final Deferred<T> deferred = new Deferred<>();
        try {
            processRequest(client, deferred);
        } catch (final Exception e) {

     * @return A Promise that will be resolved with the SuggestIndexResponse
     */
    public Deferred<SuggestIndexResponse>.Promise indexFromQueryLog(final ContentIndexingContext ctx, final QueryLogReader queryLogReader,
            final int docPerReq, final long requestInterval) {
        final Deferred<SuggestIndexResponse> deferred = new Deferred<>();
        threadPool.execute(() -> {
            final long start = System.currentTimeMillis();

            // Create a real NdrBuffer mock that can handle the deferred field access
            // But only test the non-deferred parts to avoid field mocking issues

            // When: Trying to encode (may throw exception due to deferred buffer)
            // Then: Should at least call the basic encoding methods before hitting deferred
            assertThrows(Exception.class, () -> {

        nb.index = idx;
        nb.deferred = deferred;
        return nb;
    }

    /**
     * Resets the buffer position to the start.
     */
    public void reset() {
        this.index = start;
        length = 0;
        deferred = this;
    }

    /**
     * Returns the current index position in the buffer.
     *
     * @return the current index
     */

    @Mock
    private NdrBuffer mockDeferredBuffer;

    @BeforeEach
    void setUp() {
        MockitoAnnotations.openMocks(this);
        // Set the deferred field directly since it's a public field, not a method
        mockNdrBuffer.deferred = mockDeferredBuffer;
        lenient().when(mockNdrBuffer.derive(anyInt())).thenReturn(mockDeferredBuffer);

                    deferred.reject(new SuggesterException("Search failure. Failed shards num:" + searchResponse.getFailedShards()));
                } else {
                    deferred.resolve(createResponse(searchResponse));
                }
            }

            @Override
            public void onFailure(final Exception e) {
                deferred.reject(e);
            }
        });
    }

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.suggest.request;

import org.codelibs.fess.suggest.concurrent.Deferred;
import org.opensearch.transport.client.Client;

/**
 * An abstract class that serves as a builder for creating and executing requests.
 *
 * @param <Req> the type of the request

        final NdrBuffer nb = new NdrBuffer(this.buf, this.start);
        nb.index = idx;
        nb.deferred = this.deferred;
        return nb;
    }

    /**
     * Resets the buffer position to the start.
     */
    public void reset() {
        this.index = this.start;
        this.length = 0;
        this.deferred = this;
    }

    /**
     * Returns the current index position in the buffer.
     *