import type { PluginListenerHandle } from '@capacitor/core';
declare module '@capacitor/cli' {
    interface PluginsConfig {
        LiveUpdate?: {
            /**
             * The app ID is used to identify the app when using [Capawesome Cloud](https://capawesome.io/cloud/).
             *
             * This is **NOT** the same as the app identifier (e.g. `com.example.app`).
             * This is a unique identifier generated by Capawesome Cloud (e.g. `6e351b4f-69a7-415e-a057-4567df7ffe94`).
             *
             * @since 5.0.0
             * @example '6e351b4f-69a7-415e-a057-4567df7ffe94'
             */
            appId?: string;
            /**
             * Whether or not to automatically block bundles that have been rolled back.
             *
             * When enabled, the plugin will automatically block bundles that caused a rollback
             * (up to 100 bundles). When the limit is reached, the oldest blocked bundle is unblocked.
             * Blocked bundles will be skipped in future sync operations.
             *
             * **Attention**: This option has no effect if `readyTimeout` is set to `0`.
             *
             * Only available on Android and iOS.
             *
             * @since 7.3.0
             * @default false
             */
            autoBlockRolledBackBundles?: boolean;
            /**
             * Whether or not to automatically delete unused bundles.
             *
             * When enabled, the plugin will automatically delete unused bundles after calling `ready()`.
             *
             * @since 5.0.0
             * @default false
             */
            autoDeleteBundles?: boolean;
            /**
             * The auto-update strategy for live updates.
             *
             * - `none`: Live updates will not be applied automatically.
             * - `background`: Live updates will be automatically downloaded
             * and applied in the background at app startup and when the app resumes
             * (if the last check was more than 15 minutes ago).
             *
             * Only available on Android and iOS.
             *
             * @since 7.3.0
             * @default 'none'
             * @example 'background'
             */
            autoUpdateStrategy?: 'none' | 'background';
            /**
             * The default channel of the app.
             *
             * This can be overridden by `setChannel()`, the `channel` parameter of `sync()`,
             * or the native channel configuration
             * (`CapawesomeLiveUpdateDefaultChannel` in `Info.plist` on iOS or `capawesome_live_update_default_channel`
             * in `strings.xml` on Android).
             *
             * @since 6.3.0
             * @example 'production'
             */
            defaultChannel?: string;
            /**
             * The timeout in milliseconds for HTTP requests.
             *
             * @since 6.4.0
             * @default 60000
             */
            httpTimeout?: number;
            /**
             * The public key to verify the integrity of the bundle.
             *
             * The public key must be a PEM-encoded RSA public key.
             *
             * @since 6.1.0
             * @example '-----BEGIN PUBLIC KEY-----MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDDodf1SD0OOn6hIlDuKBza0Ed0OqtwyVJwiyjmE9BJaZ7y8ZUfcF+SKmd0l2cDPM45XIg2tAFux5n29uoKyHwSt+6tCi5CJA5Z1/1eZruRRqABLonV77KS3HUtvOgqRLDnKSV89dYZkM++NwmzOPgIF422mvc+VukcVOBfc8/AHQIDAQAB-----END PUBLIC KEY-----'
             */
            publicKey?: string;
            /**
             * The timeout in milliseconds to wait for the app to be ready
             * before resetting to the default bundle.
             *
             * It is strongly **recommended** to configure this option (e.g. `10000` ms)
             * so that the plugin can roll back to the default bundle in case of problems.
             * If configured, the plugin will wait for the app to call the `ready()`
             * method before resetting to the default bundle.
             *
             * Set to `0` to disable the timeout.
             *
             * @since 5.0.0
             * @default 0
             * @example 10000
             */
            readyTimeout?: number;
            /**
             * The API domain of the [Capawesome Cloud](https://cloud.capawesome.io) server **without** scheme or path.
             *
             * @since 7.0.0
             * @default 'api.cloud.capawesome.io'
             * @example 'api.cloud.capawesome.eu'
             */
            serverDomain?: string;
        };
    }
}
export interface LiveUpdatePlugin {
    /**
     * Clear all blocked bundles from the blocked list.
     *
     * This removes all bundle identifiers that were automatically blocked
     * due to rollbacks when `autoBlockRolledBackBundles` is enabled.
     *
     * Only available on Android and iOS.
     *
     * @since 7.4.0
     */
    clearBlockedBundles(): Promise<void>;
    /**
     * Delete a bundle from the app.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    deleteBundle(options: DeleteBundleOptions): Promise<void>;
    /**
     * Download a bundle.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    downloadBundle(options: DownloadBundleOptions): Promise<void>;
    /**
     * Fetch channels from [Capawesome Cloud](https://capawesome.io/cloud/).
     *
     * This is primarily intended for development and QA purposes.
     * It allows you to retrieve a list of available channels so you can
     * dynamically switch between them using `setChannel(...)`.
     *
     * **Attention**: Only works for apps with public channels enabled.
     * If channels are private, they can still be set using `setChannel(...)`
     * but won't be returned by this method.
     *
     * Only available on Android and iOS.
     *
     * @since 8.2.0
     */
    fetchChannels(options?: FetchChannelsOptions): Promise<FetchChannelsResult>;
    /**
     * Fetch the latest bundle using the [Capawesome Cloud](https://capawesome.io/cloud/).
     *
     * Only available on Android and iOS.
     *
     * @since 6.6.0
     */
    fetchLatestBundle(options?: FetchLatestBundleOptions): Promise<FetchLatestBundleResult>;
    /**
     * Get all blocked bundle identifiers.
     *
     * Returns the list of bundle identifiers that were automatically blocked
     * due to rollbacks when `autoBlockRolledBackBundles` is enabled.
     *
     * Only available on Android and iOS.
     *
     * @since 7.4.0
     */
    getBlockedBundles(): Promise<GetBlockedBundlesResult>;
    /**
     * Get all identifiers of bundles that have been downloaded.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     * @deprecated Use `getDownloadedBundles()` instead.
     */
    getBundles(): Promise<GetBundlesResult>;
    /**
     * Get the channel that is used for the update.
     *
     * The channel is resolved in the following order (highest priority first):
     * 1. `setChannel()` (SharedPreferences on Android / UserDefaults on iOS)
     * 2. Native config (`CapawesomeLiveUpdateDefaultChannel` in `Info.plist` on iOS or
     *    `capawesome_live_update_default_channel` in `strings.xml` on Android)
     * 3. Capacitor config `defaultChannel`
     *
     * **Note**: The `channel` parameter of `sync()` takes the highest priority
     * but is not persisted and therefore not returned by this method.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    getChannel(): Promise<GetChannelResult>;
    /**
     * Get the runtime configuration.
     *
     * Returns the current plugin configuration including any runtime
     * overrides set via `setConfig()`.
     *
     * Only available on Android and iOS.
     *
     * @since 7.4.0
     */
    getConfig(): Promise<GetConfigResult>;
    /**
     * Get all identifiers of bundles that have been downloaded.
     *
     * Only available on Android and iOS.
     *
     * @since 7.4.0
     */
    getDownloadedBundles(): Promise<GetDownloadedBundlesResult>;
    /**
     * Get the bundle identifier of the current bundle.
     * The current bundle is the bundle that is currently used by the app.
     *
     * Only available on Android and iOS.
     *
     * @since 6.7.0
     */
    getCurrentBundle(): Promise<GetCurrentBundleResult>;
    /**
     * Get the custom identifier of the device.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    getCustomId(): Promise<GetCustomIdResult>;
    /**
     * Get the unique device identifier.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    getDeviceId(): Promise<GetDeviceIdResult>;
    /**
     * Check whether a sync operation is currently in progress.
     *
     * Only available on Android and iOS.
     *
     * @since 7.4.0
     */
    isSyncing(): Promise<IsSyncingResult>;
    /**
     * Get the bundle identifier of the next bundle.
     * The next bundle is the bundle that will be used after calling `reload()`
     * or restarting the app.
     *
     * Only available on Android and iOS.
     *
     * @since 6.7.0
     */
    getNextBundle(): Promise<GetNextBundleResult>;
    /**
     * Get the version code of the app.
     *
     * On **Android**, this is the `versionCode` from the `android/app/build.gradle` file.
     * On **iOS**, this is the `CFBundleVersion` from the `Info.plist` file.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    getVersionCode(): Promise<GetVersionCodeResult>;
    /**
     * Get the version name of the app.
     *
     * On **Android**, this is the `versionName` from the `android/app/build.gradle` file.
     * On **iOS**, this is the `CFBundleShortVersionString` from the `Info.plist` file.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    getVersionName(): Promise<GetVersionNameResult>;
    /**
     * Notify the plugin that the app is ready to use and no rollback is needed.
     *
     * **Attention**: This method should be called as soon as the app is ready to use
     * to prevent the app from being reset to the default bundle.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    ready(): Promise<ReadyResult>;
    /**
     * Reload the app to apply the new bundle.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    reload(): Promise<void>;
    /**
     * Reset the app to the default bundle.
     *
     * Call `reload()` or restart the app to apply the changes.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    reset(): Promise<void>;
    /**
     * Reset the runtime configuration to the values from the Capacitor config file.
     *
     * This clears any runtime configuration set via `setConfig()`.
     * The changes take effect immediately.
     *
     * Only available on Android and iOS.
     *
     * @since 7.4.0
     */
    resetConfig(): Promise<void>;
    /**
     * Set the channel to use for the update.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    setChannel(options: SetChannelOptions): Promise<void>;
    /**
     * Set the runtime configuration.
     *
     * This allows updating plugin configuration options at runtime.
     * The changes are persisted across app restarts and take effect immediately.
     *
     * **Important:** Runtime configuration is automatically reset to default values
     * whenever the native app is updated to a new version. This ensures that
     * configuration from previous versions doesn't persist after an app update.
     *
     * Only available on Android and iOS.
     *
     * @since 7.4.0
     */
    setConfig(options: SetConfigOptions): Promise<void>;
    /**
     * Set the custom identifier of the device.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    setCustomId(options: SetCustomIdOptions): Promise<void>;
    /**
     * Set the next bundle to use for the app.
     *
     * Call `reload()` or restart the app to apply the changes.
     *
     * Only available on Android and iOS.
     *
     * @since 6.7.0
     */
    setNextBundle(options: SetNextBundleOptions): Promise<void>;
    /**
     * Automatically download and set the latest bundle for the app using the [Capawesome Cloud](https://capawesome.io/cloud/).
     *
     * Call `reload()` or restart the app to apply the changes.
     *
     * Only available on Android and iOS.
     *
     * @since 5.0.0
     */
    sync(options?: SyncOptions): Promise<SyncResult>;
    /**
     * Listen for the download progress of a bundle.
     *
     * Only available on Android and iOS.
     *
     * @since 7.0.0
     */
    addListener(eventName: 'downloadBundleProgress', listenerFunc: DownloadBundleProgressListener): Promise<PluginListenerHandle>;
    /**
     * Listen for when a bundle is set as the next bundle.
     *
     * This event is triggered whenever a bundle is set to be used on the next app restart,
     * either through automatic updates or manual calls to `setNextBundle()`.
     *
     * Only available on Android and iOS.
     *
     * @since 7.3.0
     */
    addListener(eventName: 'nextBundleSet', listenerFunc: NextBundleSetListener): Promise<PluginListenerHandle>;
    /**
     * Listen for when the app is reloaded.
     *
     * This event is triggered after the `reload()` method is called
     * and the app has been reloaded.
     *
     * **Note:** To verify whether an update was successfully applied after a reload,
     * use the `ready()` method instead. The `ready()` method provides detailed information
     * about the current bundle, previous bundle, and whether a rollback occurred.
     *
     * Only available on Android and iOS.
     *
     * @since 7.4.0
     */
    addListener(eventName: 'reloaded', listenerFunc: ReloadedListener): Promise<PluginListenerHandle>;
    /**
     * Remove all listeners for this plugin.
     *
     * @since 7.2.0
     */
    removeAllListeners(): Promise<void>;
}
/**
 * @since 5.0.0
 */
export interface DeleteBundleOptions {
    /**
     * The unique identifier of the bundle to delete.
     *
     * @since 5.0.0
     * @example '1.0.0'
     */
    bundleId: string;
}
export interface DownloadBundleOptions {
    /**
     * The artifact type of the bundle.
     *
     * @since 6.6.0
     * @default 'zip'
     * @example 'manifest'
     */
    artifactType?: 'manifest' | 'zip';
    /**
     * The unique identifier of the bundle.
     *
     * **Attention**: The value `public` is reserved and cannot be used as a bundle identifier.
     *
     * @since 5.0.0
     * @example '1.0.0'
     */
    bundleId: string;
    /**
     * The checksum of the self-hosted bundle as a SHA-256 hash
     * in hex format to verify the integrity of the bundle.
     *
     * **Attention**: Only supported for the `zip` artifact type.
     *
     * @since 7.1.0
     */
    checksum?: string;
    /**
     * The signature of the self-hosted bundle as a signed SHA-256 hash
     * in base64 format to verify the integrity of the bundle.
     *
     * **Attention**: Only supported for the `zip` artifact type.
     *
     * @since 7.1.0
     */
    signature?: string;
    /**
     * The URL of the bundle to download.
     *
     * For the `zip` artifact type, the URL must point to a ZIP file.
     * For the `manifest` artifact type, the URL serves as the base URL
     * to download the individual files. For example, if the URL is
     * `https://example.com/download`, the plugin will download the file
     * with the href `index.html` from `https://example.com/download?href=index.html`.
     *
     * To **verify the integrity** of the file, the server should return
     * a `X-Checksum` header with the SHA-256 hash in hex format.
     *
     * To **verify the signature** of the file, the server should return
     * a `X-Signature` header with the signed SHA-256 hash in base64 format.
     *
     * @since 5.0.0
     * @example 'https://example.com/bundle.zip'
     */
    url: string;
}
/**
 * @since 8.2.0
 */
export interface FetchChannelsOptions {
    /**
     * The maximum number of channels to return.
     *
     * @since 8.2.0
     * @default 50
     */
    limit?: number;
    /**
     * The number of channels to skip.
     *
     * @since 8.2.0
     * @default 0
     */
    offset?: number;
    /**
     * The query to filter channels by name.
     *
     * @since 8.2.0
     */
    query?: string;
}
/**
 * @since 8.2.0
 */
export interface FetchChannelsResult {
    /**
     * The list of channels.
     *
     * @since 8.2.0
     */
    channels: Channel[];
}
/**
 * @since 8.2.0
 */
export interface Channel {
    /**
     * The unique identifier of the channel.
     *
     * @since 8.2.0
     */
    id: string;
    /**
     * The name of the channel.
     *
     * @since 8.2.0
     */
    name: string;
}
/**
 * @since 6.7.0
 */
export interface FetchLatestBundleOptions {
    /**
     * The name of the channel where the latest bundle is fetched from.
     *
     * @since 6.7.0
     */
    channel?: string;
}
/**
 * @since 6.6.0
 */
export interface FetchLatestBundleResult {
    /**
     * The artifact type of the bundle.
     *
     * @since 6.7.0
     */
    artifactType?: 'manifest' | 'zip';
    /**
     * The unique identifier of the latest bundle.
     *
     * On Capawesome Cloud, this is the ID of the app build artifact.
     *
     * If `null`, no bundle is available.
     *
     * @since 6.6.0
     */
    bundleId: string | null;
    /**
     * The checksum of the latest bundle if the bundle is self-hosted.
     *
     * If the bundle is hosted on Capawesome Cloud, the checksum will be
     * returned as response header when downloading the bundle.
     *
     * @since 7.1.0
     */
    checksum?: string;
    /**
     * Custom properties that are associated with the latest bundle.
     *
     * @since 7.0.0
     * @example { "key": "value" }
     */
    customProperties?: {
        [key: string]: string;
    };
    /**
     * The URL of the latest bundle to download.
     * Pass this URL to the `downloadBundle(...)` method to download the bundle.
     *
     * @since 6.7.0
     */
    downloadUrl?: string;
    /**
     * The signature of the latest bundle if the bundle is self-hosted.
     *
     * If the bundle is hosted on Capawesome Cloud, the signature will be
     * returned as response header when downloading the bundle.
     *
     * @since 7.1.0
     */
    signature?: string;
}
/**
 * @since 5.0.0
 */
export interface GetBundleResult {
    /**
     * The unique identifier of the active bundle.
     *
     * If `null`, the default bundle is being used.
     *
     * @since 5.0.0
     * @example '1.0.0'
     */
    bundleId: string | null;
}
/**
 * @since 7.4.0
 */
export interface GetBlockedBundlesResult {
    /**
     * An array of unique identifiers of all blocked bundles.
     *
     * @since 7.4.0
     */
    bundleIds: string[];
}
/**
 * @since 5.0.0
 */
export interface GetBundlesResult {
    /**
     * An array of unique identifiers of all available bundles.
     *
     * @since 5.0.0
     */
    bundleIds: string[];
}
/**
 * @since 7.4.0
 */
export interface GetDownloadedBundlesResult {
    /**
     * An array of unique identifiers of all downloaded bundles.
     *
     * @since 7.4.0
     */
    bundleIds: string[];
}
/**
 * @since 5.0.0
 */
export interface GetChannelResult {
    /**
     * The channel name.
     *
     * If `null`, the app is using the default channel.
     *
     * @since 5.0.0
     * @example 'production'
     */
    channel: string | null;
}
/**
 * @since 7.4.0
 */
export interface GetConfigResult {
    /**
     * The app ID used to identify the app.
     *
     * If `null`, no app ID is configured.
     *
     * @since 7.4.0
     * @example '6e351b4f-69a7-415e-a057-4567df7ffe94'
     */
    appId: string | null;
    /**
     * The auto-update strategy for live updates.
     *
     * @since 7.4.0
     * @example 'background'
     */
    autoUpdateStrategy: 'none' | 'background';
}
/**
 * @since 6.7.0
 */
export interface GetCurrentBundleResult {
    /**
     * The unique identifier of the current bundle.
     *
     * If `null`, the default bundle is being used.
     *
     * @since 6.7.0
     */
    bundleId: string | null;
}
/**
 * @since 5.0.0
 */
export interface GetDeviceIdResult {
    /**
     * The unique identifier of the device.
     *
     * On iOS, [`identifierForVendor`](https://developer.apple.com/documentation/uikit/uidevice/1620059-identifierforvendor) is used.
     * The value of this property is the same for apps that come from the same vendor running on the same device.
     *
     * @since 5.0.0
     *
     * @example '50d2a548-80b7-4dad-adc7-97c0e79d8a89'
     */
    deviceId: string;
}
/**
 * @since 7.4.0
 */
export interface IsSyncingResult {
    /**
     * Whether a sync operation is currently in progress.
     *
     * @since 7.4.0
     */
    syncing: boolean;
}
/**
 * @since 6.7.0
 */
export interface GetNextBundleResult {
    /**
     * The unique identifier of the next bundle.
     *
     * If `null`, the default bundle is being used.
     *
     * @since 6.7.0
     */
    bundleId: string | null;
}
/**
 * @since 5.0.0
 */
export interface GetVersionCodeResult {
    /**
     * The version code of the app.
     *
     * On **Android**, this is the `versionCode` from the `android/app/build.gradle` file.
     * On **iOS**, this is the `CFBundleVersion` from the `Info.plist` file.
     *
     * @since 5.0.0
     * @example "1"
     */
    versionCode: string;
}
/**
 * @since 5.0.0
 */
export interface GetVersionNameResult {
    /**
     * The version name of the app.
     *
     * On **Android**, this is the `versionName` from the `android/app/build.gradle` file.
     * On **iOS**, this is the `CFBundleShortVersionString` from the `Info.plist` file.
     *
     * @since 5.0.0
     * @example "1.0.0"
     */
    versionName: string;
}
/**
 * @since 5.0.0
 */
export interface GetCustomIdResult {
    /**
     * The custom identifier of the device.
     *
     * If `null`, no custom identifier is set.
     *
     * @since 5.0.0
     * @example '50d2a548-80b7-4dad-adc7-97c0e79d8a89'
     */
    customId: string | null;
}
/**
 * @since 7.0.0
 */
export interface ReadyResult {
    /**
     * The identifier of the previous bundle used.
     *
     * If `null`, the default bundle was used.
     *
     * @since 7.0.0
     */
    previousBundleId: string | null;
    /**
     * The identifier of the current bundle used.
     *
     * If `null`, the default bundle is being used.
     *
     * @since 7.0.0
     */
    currentBundleId: string | null;
    /**
     * Whether or not the app was reset to the default bundle.
     *
     * @since 7.0.0
     */
    rollback: boolean;
}
/**
 * @since 5.0.0
 */
export interface SetBundleOptions {
    /**
     * The unique identifier of the bundle to use.
     *
     * @since 5.0.0
     * @example '1.0.0'
     */
    bundleId: string;
}
/**
 * @since 5.0.0
 */
export interface SetChannelOptions {
    /**
     * The channel name.
     *
     * Set `null` to remove the channel.
     *
     * @since 5.0.0
     */
    channel: string | null;
}
/**
 * @since 7.4.0
 */
export interface SetConfigOptions {
    /**
     * The app ID used to identify the app.
     *
     * Set `null` to reset to the value from the Capacitor config file.
     *
     * @since 7.4.0
     * @example '6e351b4f-69a7-415e-a057-4567df7ffe94'
     */
    appId?: string | null;
}
/**
 * @since 5.0.0
 */
export interface SetCustomIdOptions {
    /**
     * The custom identifier of the device.
     *
     * Set `null` to remove the custom identifier.
     *
     * @since 5.0.0
     */
    customId: string | null;
}
/**
 * @since 6.7.0
 */
export interface SetNextBundleOptions {
    /**
     * The unique identifier of the bundle to use.
     *
     * Set `null` to use the default bundle (same as calling `reset()`).
     *
     * @since 6.7.0
     * @example '1.0.0'
     */
    bundleId: string | null;
}
/**
 * @since 6.7.0
 */
export interface SyncOptions {
    /**
     * The name of the channel where the latest bundle is fetched from.
     *
     * @since 6.7.0
     */
    channel?: string;
}
/**
 * @since 5.0.0
 */
export interface SyncResult {
    /**
     * The identifier of the next bundle to use.
     *
     * If `null`, the app is up-to-date and no new bundle is available.
     *
     * @since 5.0.0
     */
    nextBundleId: string | null;
}
/**
 * Listener for the download progress of a bundle.
 *
 * @since 7.0.0
 */
export type DownloadBundleProgressListener = (event: DownloadBundleProgressEvent) => void;
/**
 * Event that is triggered when the download progress of a bundle changes.
 *
 * @since 7.0.0
 */
export interface DownloadBundleProgressEvent {
    /**
     * The unique identifier of the bundle that is being downloaded.
     *
     * @since 7.0.0
     */
    bundleId: string;
    /**
     * The number of bytes that have been downloaded.
     *
     * @since 7.0.0
     */
    downloadedBytes: number;
    /**
     * The progress of the download in percent as a value between `0` and `1`.
     *
     * @since 7.0.0
     * @example 0.5
     */
    progress: number;
    /**
     * The total number of bytes to download.
     *
     * @since 7.0.0
     */
    totalBytes: number;
}
/**
 * Listener for when a bundle is set as the next bundle.
 *
 * @since 7.3.0
 */
export type NextBundleSetListener = (event: NextBundleSetEvent) => void;
/**
 * Event that is triggered when a bundle is set as the next bundle.
 *
 * @since 7.3.0
 */
export interface NextBundleSetEvent {
    /**
     * The unique identifier of the bundle that is set as the next bundle.
     *
     * If `null`, the default bundle will be used.
     *
     * @since 7.3.0
     * @example '1.0.0'
     */
    bundleId: string | null;
}
/**
 * Listener for when the app is reloaded.
 *
 * @since 7.4.0
 */
export type ReloadedListener = () => void;