/**
 * Whether a display line is a form feed line, for --form-feed: the raw
 * `\f` (-r) or its caret rendering.
 */
export declare const isFormFeed: (line: string) => boolean;
/**
 * Caps a forward scroll at less's --form-feed stop: forw() checks each
 * newly printed bottom line (forwback.c:366) and breaks with the \f
 * line as the LAST visible row on screen.
 */
export declare function ffCapForward(content: string[], offset: number): number;
/**
 * How far a backward move may go before a form feed stops it.
 *
 * less's back() prints each newly exposed line at the TOP and breaks
 * after one that starts with \f (forwback.c:444), so the form feed
 * ends up the first visible row. Jumps pass do_stop_on_form_feed
 * FALSE and never stop.
 *
 * @param content - Full content lines.
 * @param offset - Display rows the move wants.
 * @returns The rows it may actually take.
 */
export declare function ffCapBackward(content: string[], offset: number): number;
export declare function lineForward(content: string[], offset: number, ignoreEOF?: boolean, attn?: boolean): void;
/**
 * Scroll backward by the given offset.
 *
 * - Stops and rings bell at BOF, also disables `mode.INIT`.
 * - In chopped mode, moves by whole lines.
 * - In wrapped mode, moves by sub-rows within a line.
 *
 * @param content - Full content lines.
 * @param offset - Lines or sub-rows to scroll backward.
 */
export declare function lineBackward(content: string[], offset: number, attn?: boolean): number;
/**
 * Scrolls backward past the beginning of the file (K, Y, ESC-b), like
 * less's forced back() padding blank lines above the first line.
 *
 * @param content - Full content lines.
 * @param offset - Lines or sub-rows to scroll backward.
 */
export declare function forceLineBackward(content: string[], offset: number, screenful?: boolean): void;
/**
 * Scrolls forward by whole file lines (ESC-j), like less's to_newline
 * forw: wrapped sub-rows always land on a line boundary.
 *
 * @param content - Full content lines.
 * @param offset - File lines to move forward.
 */
export declare function newlineForward(content: string[], offset: number): void;
/**
 * Scrolls backward by whole file lines (ESC-k), like less's to_newline
 * back.
 *
 * @param content - Full content lines.
 * @param offset - File lines to move backward.
 */
export declare function newlineBackward(content: string[], offset: number): void;
/** Registers (or clears) the -e forward-at-EOF handler. */
export declare function onEofForward(fn: (() => boolean) | null): void;
/**
 * Scrolls the view forward by a window size.
 *
 * - If `buffer` is a valid number, it overrides the default window size.
 * - Falls back to the -z scroll window (less's get_swindow) if `buffer`
 *   is invalid.
 * - If `ignoreEOF` is `true`, allows scrolling beyond (END) without clamping.
 *
 * @param content - The full content to paginate.
 * @param buffer - A string array that represents the number of lines to scroll.
 * @param ignoreEOF - Whether to bypass EOF constraints during scrolling.
 */
export declare function windowForward(content: string[], buffer: string[], ignoreEOF?: boolean): void;
/**
 * Moves the view backward by one window.
 *
 * - If `buffer` is a valid number, uses it as the offset.
 * - Otherwise, uses the -z scroll window (less's get_swindow).
 *
 * @param content - The full content as an array of lines.
 * @param buffer - A string array that represents the number of lines to scroll.
 */
export declare function windowBackward(content: string[], buffer: string[]): void;
/**
 * Sets a custom window size using the given `buffer`, and scrolls forward.
 *
 * - If `buffer` is a valid number, updates `config.setWindow` with it.
 * - Then scrolls forward by the -z scroll window (less's get_swindow).
 *
 * @param content - The full content as an array of lines.
 * @param buffer - A string array that represents the number of lines to scroll.
 */
export declare function setWindowForward(content: string[], buffer: string[]): void;
/**
 * Sets a custom window size using the given `buffer`, and scrolls backward.
 *
 * - If `buffer` is a valid number, updates `config.setWindow` with it.
 * - Then scrolls backward by the -z scroll window (less's get_swindow).
 *
 * @param content - The full content as an array of lines.
 * @param buffer - A string array that represents the number of lines to scroll.
 */
export declare function setWindowBackward(content: string[], buffer: string[]): void;
/**
 * Sets a custom half-window size using the given `buffer`, and scrolls forward.
 *
 * - If `buffer` is a valid number, updates `config.setHalfWindow` with it.
 * - Then scrolls forward by `config.setHalfWindow` or falls back to
 *   `config.halfWindow`.
 *
 * @param content - The full content as an array of lines.
 * @param buffer - A string array that represents the number of lines to scroll.
 */
export declare function setHalfWindowForward(content: string[], buffer: string[]): void;
/**
 * Sets a custom half-window size using the given `buffer`, and scrolls
 * backward.
 *
 * - If `buffer` is a valid number, updates `config.setHalfWindow` with it.
 * - Then scrolls backward by `config.setHalfWindow` or falls back to
 *   `config.halfWindow`.
 *
 * @param content - The full content as an array of lines.
 * @param buffer - A string array that represents the number of lines to scroll.
 */
export declare function setHalfWindowBackward(content: string[], buffer: string[]): void;
export declare function setHalfScreenRight(buffer: string[]): void;
/**
 * Scrolls left by buffer value or half screen width.
 *
 * @param buffer - Buffer containing scroll offset.
 */
export declare function setHalfScreenLeft(buffer: string[]): void;
/**
 * Scrolls right to the last column displayed.
 *
 * - Shifts the view so the longest currently displayed line ends at the
 *   right edge of the screen.
 *
 * @param content - Full content lines.
 */
export declare function lastCol(content: string[]): void;
/**
 * Scrolls left to the first column.
 */
export declare function firstCol(): void;