/**
 * Copyright 2018 Google Inc.
 *
 * 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 { BatchId, MutationBatchState, TargetId } from '../core/types';
import { FirestoreError } from '../util/error';
import { ClientId } from './shared_client_state';
/** The different states of a watch target. */
export declare type QueryTargetState = 'not-current' | 'current' | 'rejected';
/**
 * An interface that describes the actions the SharedClientState class needs to
 * perform on a cooperating synchronization engine.
 */
export interface SharedClientStateSyncer {
    /** Applies a mutation state to an existing batch.  */
    applyBatchState(batchId: BatchId, state: MutationBatchState, error?: FirestoreError): Promise<void>;
    /** Applies a query target change from a different tab. */
    applyTargetState(targetId: TargetId, state: QueryTargetState, error?: FirestoreError): Promise<void>;
    /** Adds or removes Watch targets for queries from different tabs. */
    applyActiveTargetsChange(added: TargetId[], removed: TargetId[]): Promise<void>;
    /** Returns the IDs of the clients that are currently active. */
    getActiveClients(): Promise<ClientId[]>;
}
