/**
 * @license
 * Copyright 2022 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
import { AggregateField, AggregateQuerySnapshot, AggregateSpec } from '../lite-api/aggregate_types';
import { DocumentData, Query } from '../lite-api/reference';
export { aggregateQuerySnapshotEqual, count, sum, average, aggregateFieldEqual } from '../lite-api/aggregate';
/**
 * Calculates the number of documents in the result set of the given query
 * without actually downloading the documents.
 *
 * Using this function to count the documents is efficient because only the
 * final count, not the documents' data, is downloaded. This function can
 * count the documents in cases where the result set is prohibitively large to
 * download entirely (thousands of documents).
 *
 * The result received from the server is presented, unaltered, without
 * considering any local state. That is, documents in the local cache are not
 * taken into consideration, neither are local modifications not yet
 * synchronized with the server. Previously-downloaded results, if any, are not
 * used. Every invocation of this function necessarily involves a round trip to
 * the server.
 *
 * @param query - The query whose result set size is calculated.
 * @returns A Promise that will be resolved with the count; the count can be
 * retrieved from `snapshot.data().count`, where `snapshot` is the
 * `AggregateQuerySnapshot` to which the returned Promise resolves.
 */
export declare function getCountFromServer<AppModelType, DbModelType extends DocumentData>(query: Query<AppModelType, DbModelType>): Promise<AggregateQuerySnapshot<{
    count: AggregateField<number>;
}, AppModelType, DbModelType>>;
/**
 * Calculates the specified aggregations over the documents in the result
 * set of the given query without actually downloading the documents.
 *
 * Using this function to perform aggregations is efficient because only the
 * final aggregation values, not the documents' data, are downloaded. This
 * function can perform aggregations of the documents in cases where the result
 * set is prohibitively large to download entirely (thousands of documents).
 *
 * The result received from the server is presented, unaltered, without
 * considering any local state. That is, documents in the local cache are not
 * taken into consideration, neither are local modifications not yet
 * synchronized with the server. Previously-downloaded results, if any, are not
 * used. Every invocation of this function necessarily involves a round trip to
 * the server.
 *
 * @param query - The query whose result set is aggregated over.
 * @param aggregateSpec - An `AggregateSpec` object that specifies the aggregates
 * to perform over the result set. The AggregateSpec specifies aliases for each
 * aggregate, which can be used to retrieve the aggregate result.
 * @example
 * ```typescript
 * const aggregateSnapshot = await getAggregateFromServer(query, {
 *   countOfDocs: count(),
 *   totalHours: sum('hours'),
 *   averageScore: average('score')
 * });
 *
 * const countOfDocs: number = aggregateSnapshot.data().countOfDocs;
 * const totalHours: number = aggregateSnapshot.data().totalHours;
 * const averageScore: number | null = aggregateSnapshot.data().averageScore;
 * ```
 */
export declare function getAggregateFromServer<AggregateSpecType extends AggregateSpec, AppModelType, DbModelType extends DocumentData>(query: Query<AppModelType, DbModelType>, aggregateSpec: AggregateSpecType): Promise<AggregateQuerySnapshot<AggregateSpecType, AppModelType, DbModelType>>;