import { ConversationState } from "./flex-ui-core/src";
import { Call } from "@twilio/voice-sdk";
import { Reservation } from "twilio-taskrouter";
import { ITask } from "./models";
/**
 * @classdesc Helper class for state.
 * @hideconstructor
 * @category State Management
 */
export declare class StateHelper {
    /**
     * Get current call state if one exists.
     * @static
     * @returns {Call| undefined} If it does not exist.
     * @example
     * import { StateHelper } from "@twilio/flex-ui";
     * const activeCall = StateHelper.getCurrentPhoneCallState();
     */
    static getCurrentPhoneCallState(): Call | undefined;
    /**
     * Gets current chat channel state for a task.
     * @static
     * @param {ITask} task Task.
     * @returns {ConversationState.ConversationState | undefined} Chat channel state.
     * @example
     * import { StateHelper } from "@twilio/flex-ui";
     * const conversation = StateHelper.getConversationStateForTask(myConversationTask);
     */
    static getConversationStateForTask(task: ITask): ConversationState.ConversationState | undefined;
    /**
     * @private
     * @deprecated
     * @deprecatedSince 2.0.0
     * @altRecommendation Use `StateHelper.getConversationStateForTask` instead.
     * @altRecommendationExample
     * import { StateHelper } from "@twilio/flex-ui";
     * const conversation = StateHelper.getConversationStateForTask(myConversationTask);
     * @altRecommendationLink https://assets.flex.twilio.com/docs/releases/flex-ui/latest/advanced/state-management/StateHelper/
     */
    static getChatChannelStateForTask(task: ITask): import("./flex-ui-core/src/state/ChannelState").ChannelState;
    /**
     * Gets TaskRouter Reservation object.
     * @static
     * @param {string} reservationSid Reservation sid to retrieve.
     * @returns {Reservation} Reservation instance.
     * @example
     * import { StateHelper } from "@twilio/flex-ui";
     * const reservation = StateHelper.getReservation("WRXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX");
     */
    static getReservation(reservationSid: string): Reservation;
    static getTaskByTaskrouterTaskSid(sid: string): ITask<Record<string, any>>;
    /**
     * Returns true if user has a pending call reservation.
     * @static
     * @returns {boolean} If user has a pending call reservation.
     * @example
     * import { StateHelper } from "@twilio/flex-ui";
     * const isCallWaiting = StateHelper.hasPendingCall();
     */
    static hasPendingCall(): boolean;
}