import { EventSubscription } from 'react-native';
import { CodeBlockCallback, PropertiesLoadedCallback, TaplyticsFeatureFlags, TaplyticsExperiments, TaplyticsVariableMap } from './experiments.types';
/**
 * `runCodeBlock` takes a callback that can be enabled or disabled depending on the variation.
 * If enabled, the code within the callback will be executed.
 * If disabled, the variation will not get the callback.
 *
 * By default, a code block will not run unless enabled on the Taplytics Dashboard.
 * It must be enabled for a Variation before it will run.
 *
 * @param name The name of the code block variable.
 * @param codeBlock A function that will run if the code block variable is activated.
 */
export declare const runCodeBlock: (name: string, codeBlock: CodeBlockCallback) => void;
/**
 * @deprecated Use the `setTaplyticsNewSessionListener` instead.
 *
 * Use this method to ensure that all the feature flag and experiment variables
 * have been loaded from the server prior to utilizing them. The callback
 * returns back an event subscriber that can be used to cleanup the event
 * listener using the `remove` function.
 *
 * On iOS the callback is also triggered when a new session is generated or
 * if the user's `email` or `user_id` attributes have been updated using the
 * `setUserAttributes` method.
 *
 * @param callback A function that runs once properties have been loaded.
 *
 * @returns An event subscriber object is returned. Use the `remove` function to clean up the event listener.
 */
export declare const propertiesLoadedCallback: (callback: PropertiesLoadedCallback) => EventSubscription;
/**
 * Called to determine which feature flags that are running on a given device.
 *
 * @returns A promise that resolves to an object with running feature flags' names and their associated key.
 */
export declare const getRunningFeatureFlags: () => Promise<TaplyticsFeatureFlags>;
/**
 * Determine if a particular feature flag is enabled.
 *
 * NOTE: The value of featureFlagEnabled will be determined immediately, ie. the SDK
 * will not wait for properties to be loaded from the server. Thus, if you want to ensure
 * that the variables have their correct values based on your experiment segmentation,
 * you must initialize them after the properties have been loaded from the server through
 * the `propertiesLoadedCallback` method.
 *
 * @param key The key of the feature flag.
 *
 * @returns A promise that resolves to a boolean.
 */
export declare const featureFlagEnabled: (key: string) => Promise<boolean>;
/**
 * Called to determine which variations and experiments are running on a given device.
 *
 * @returns A promise that resolves to an object of current experiments and their running variation.
 */
export declare const getRunningExperimentsAndVariations: () => Promise<TaplyticsExperiments>;
/**
 * Use this function to register a listener for whenever an experiments' variable value is changed.
 *
 * @param listener A function that is invoked whenever an experiments' variable is updated.
 */
export declare const registerVariablesChangedListener: (listener: (variables: TaplyticsVariableMap) => void | Promise<void>) => void;
/**
 * This method returns an object with experiment variables' keys and values. It only keeps track of
 * variables that have been fetched by either `newAsyncVariable` or `newSyncVariable`.
 *
 * @returns An object that holds the key's and values of the experiment variables.
 */
export declare const getVariables: () => TaplyticsVariableMap;
/**
 * This function ensures that the experiments have been loaded before returning a value.
 * This removes any danger of tainting the results of experiments with bad data.
 * However, this does mean that the value will not be set immediately. In the case that
 * the experiments fail to load, then the default value will be returned.
 *
 * @param name The name of the dynamic variable.
 * @param defaultValue Default value to be utilized for the dynamic variable.
 * @param callback A function that runs when the dynamic variable has been evaluated or updated,
 * it receives the dynamic variable value as the argument.
 *
 * @returns An event subscriber object is returned. Use the `remove` function to clean up the event listener.
 */
export declare const newAsyncVariable: <T>(name: string, defaultValue: T, callback: (variable: T) => void) => EventSubscription;
/**
 * This function is a synchronous means of retrieving a dynamic variables' value.
 * It guarantees to have the same value for the entire session and will have that
 * value immediately after construction. Ensure that the experiments have been loaded
 * in before utilizing this method via the `propertiesLoadedCallback` or `setTaplyticsNewSessionListener`
 * method, otherwise it will return the default value.
 *
 * @param name The name of the dynamic variable.
 * @param defaultValue Default value to be utilized for the dynamic variable.
 *
 * @returns A promise that resolves to the dynamic variable.
 */
export declare const newSyncVariable: <T>(name: string, defaultValue: T) => Promise<T>;