/**
 * @module prompt
 */
export interface InputFilterMeta {
    input: string;
    original: string;
    type: "line" | "char";
    userAction: boolean;
    silent: boolean;
}
export declare type InputFilter = (input: string, meta: InputFilterMeta) => boolean;
/**
 * Registers a new input filter.
 *
 * @see https://vorple-if.com/docs/filters.html#input-filters
 * @since 3.2.0
 *
 * @param filter  The input filter to register
 * @returns Returns a function that can be called to remove the filter.
 */
export declare function addInputFilter(filter: InputFilter): () => void;
/**
 * Runs input through all input filters.
 *
 * @since 3.2.0
 * @internal
 * @param originalInput  The original input
 * @param meta  Associated input meta
 */
export declare function applyInputFilters(originalInput: string, meta: InputFilterMeta): Promise<string | false>;
/**
 * Clear the command queue.
 *
 * @since 3.2.0
 */
export declare function clearCommandQueue(): void;
/**
 * Clear the keypress queue.
 *
 * @since 3.2.0
 */
export declare function clearKeyQueue(): void;
/**
 * Manually hide the prompt. It won't be shown until unhide() is called.
 */
export declare function hide(): void;
/**
 * Haven's history API.
 */
export { history } from "../haven/prompt";
/**
 * Hook into Haven's input listeners.
 */
export declare function init(): void;
/**
 * Add a command to the command queue. If the line input is ready, execute
 * the command immediately.
 *
 * @param cmd  Command to add
 * @param silent  If true, the command isn't shown on the screen.
 *      The result of the command will still print normally.
 */
export declare function queueCommand(cmd: string, silent?: boolean): void;
/**
 * Add a keypress to the command queue. If the engine is waiting for a keypress,
 * send it immediately.
 *
 * @param key A one-character string containing the pressed character
 * @since 3.2.0
 */
export declare function queueKeypress(key: string): void;
/**
 * Removes a filter from registered input filters.
 *
 * @param filter  The filter to remove
 * @returns Returns true if the filter was removed, false if the filter wasn't registered.
 * @since 3.2.0
 */
export declare function removeInputFilter(filter: InputFilter): boolean;
/**
 * Set the prefix of the command prompt. The prefix is usually a greater-than
 * character (>) at the start of the command prompt.
 *
 * The currently active command prompt is changed, and the new prefix is used
 * for all future command prompts until changed again.
 *
 * Note that calling this function directly with JavaScript changes the prompt
 * in the interpreter, but doesn't pass the information to the story file.
 * Therefore checking what the prefix is in the Inform story might not return
 * correct values because the variable that the story uses to track the prefix
 * content hasn't been changed. In most cases it's recommended to use the Vorple
 * extensions/libraries in Inform to change the prefix.
 *
 * @param prefix  The new prefix
 * @param isHtml  If true, the prefix is inserted into the DOM as HTML.
 *      Otherwise HTML is escaped and shown as-is.
 *
 *  @returns Returns the new prefix.
 */
export declare function setPrefix(prefix: string, isHtml?: boolean): string;
/**
 * Set the lineinput's value.
 *
 * @param value  The new value
 */
export declare function setValue(value: string): void;
/**
 * Trigger the submit event of the lineinput.
 *
 * @param command  The command to send, if null or left out the lineinput field's current value is used.
 * @param silent  If true, the command isn't shown on the screen.
 *      The result of the command will still print normally.
 */
export declare function submit(command?: string | null, silent?: boolean): void;
/**
 * Remove manual hiding of the prompt. It's called rather clumsily "unhide"
 * instead of "show" to stress that it only undoes what the [[hide]] method did,
 * and it doesn't force the prompt to appear if it has been hidden or removed
 * by some other means.
 */
export declare function unhide(): void;