/**
 * Option value types, like opttbl.c: BOOL toggles, TRIPLE has lower and
 * upper states, NUMBER and STRING prompt for a parameter, NOVAR runs an
 * action.
 */
/** Content-rebuild hook, set by the pager (onRebuild), the -b
 *  buffer trim hook (onTrimBufSpace), and whether the pager screen
 *  is initialized: less writes mouse/paste modes only from screen
 *  init and TOGGLE handlers, never during the option scan. */
export declare const hook: {
    rebuildContent: () => void;
    /** less's O_HL_REPAINT: re-highlight NOW, under the option's message. */
    hiliteRepaint: () => void;
    /** Rebuilds the compiled pattern, for when the ENGINE changed under
     *  it (--use-js-regexp) rather than the pattern or its case. */
    recompilePattern: () => void;
    hiliteErase: () => void;
    /** Reads the top row's character offset, returning a function that
     *  restores it once the width has changed (less's table[TOP]). */
    topOffset: (content: string[]) => () => void;
    /** Moves a source engine's own top back to its line start, for
     *  less's pos_rehead. */
    reheadSource: null | (() => void);
    /** less's opt_k: load a COMPILED lesskey file named by -k, returning
     *  false when lesskey() would have returned nonzero (unreadable,
     *  shorter than 3 bytes, or blocked by SECURE/LESSNOCONFIG). Set by
     *  features/lesskey to keep the option table free of that import. */
    loadLesskeyFile: (path: string) => boolean;
    trimBufSpace: () => void;
    screenActive: boolean;
    /** --file-size draining a still-unknown pipe (less's opt_filesize). */
    scanFileSize: () => void;
    /** Opens the lesskey syntax page, like the h command opens help. */
    showLesskeyHelp: () => void;
    /** Puts a message on the bottom row NOW, before slow work runs. */
    flashMessage: (text: string) => void;
    viewLesskey: () => void;
    /** Absolute 1-based line number for a source-backed local row. */
    sourceLineNumber: null | ((row: number) => number | null | undefined);
    /** Absolute byte position for a source-backed local row. */
    sourceBytePosition: null | ((row: number) => number | null | undefined);
    /** Total raw line count for a seekable source. */
    sourceLineCount: null | (() => number | null | undefined);
    /** Local materialized row holding the absolute header start. */
    sourceHeaderRow: null | (() => number | undefined);
    /** Moves a seekable source when --header changes its absolute start. */
    sourceHeaderChanged: null | ((start: number) => void);
    /** less's screen_trashed for an O_REPAINT option: the next
     *  make_display repaints through jump_loc, which rebuilds the screen
     *  from the position table rather than from whatever the last
     *  command left standing. */
    sourceRepaint: null | (() => void);
    /** Raw bytes between two absolute file positions, like less's
     *  pipe_data reading ch.c between spos and epos. The pipe needs the
     *  FILE, not the materialized window: session.content holds only the
     *  rows currently spooled. */
    sourceReadRange: null | ((from: number, to: number) => Buffer | null);
    /** less's curr_byte(where): the byte at a SCREEN ROW, read off the
     *  position table. A wrapped line puts several rows in one line, so
     *  this is not the line's byte - which is what makes %bB and %pB
     *  land mid-line on a long line. */
    sourceRowByte: null | ((sindex: number) => number | null);
};
/** Registers the immediate -b pool trim, like less's ch_setbufspace. */
export declare function onTrimBufSpace(fn: () => void): void;
/** Per prompt style --end-prompt strings (short, medium, long). */
export declare const endPrompts: (string | null)[];
/** Default search modifiers set by --search-options. */
declare const defSearchType: {
    pastEof: boolean;
    fromStart: boolean;
    keep: boolean;
    invert: boolean;
    noRegex: boolean;
    wrap: boolean;
    subs: Set<number>;
};
export declare const EMOUSE_HSCROLL = 1;
export declare const EMOUSE_VSCROLL = 2;
export declare const EMOUSE_HDRAG = 4;
export declare const EMOUSE_VDRAG = 8;
export declare const EMOUSE_LCLICK = 16;
export declare const EMOUSE_RCLICK = 32;
/** Fresh-search start mode of -a/-A (less's how_search). */
export declare const optHowSearch: () => number;
/** Match highlighting mode of -g/-G (less's hilite_search). */
export declare const optHiliteSearch: () => number;
/** State 2 of -e/-E etc, read by the pager loop; $LESS_IS_MORE maps
 *  the flag onto more's -e semantics, like less's get_quit_at_eof. */
export declare const optQuitAtEof: () => number;
/** Bell suppression level of -q/-Q. */
export declare const optQuiet: () => number;
/** True when -c forces full repaints instead of scrolling. */
export declare const optClearRepaint: () => boolean;
/** Backward scroll limit of -h, -1 when unlimited. */
export declare const optBackScroll: () => number;
/** Forward scroll limit of -y, -1 when unlimited. */
export declare const optForwScroll: () => number;
/** True when -K makes ctrl-C exit the pager. */
export declare const optQuitOnIntr: () => boolean;
/** True when -F quits a file that fits on the first screen. */
export declare const optQuitIfOneScreen: () => boolean;
/** The prompt style used for display: more mode defaults to medium
 *  and -m selects short, like less's pr_string type mapping. */
export declare const displayPrType: () => number;
/** Line number mode of -n/-N (0 off, 1 on, 2 displayed). */
export declare const optLinenums: () => number;
/** Control char display of -r/-R (0 caret, 1 raw, 2 ANSI through). */
export declare const optCtldisp: () => number;
/** True when -s squeezes runs of blank lines. */
export declare const optSqueeze: () => boolean;
/** Unread-line highlight mode of -w/-W (less's show_attn). */
export declare const optShowAttn: () => number;
/** True when -J displays the status column. */
export declare const optStatusCol: () => boolean;
/** The -" shell quote characters. */
export declare const optQuotes: () => {
    open: string;
    close: string;
};
/** True when tildes pad past end of file (-~ default on). */
export declare const optTildes: () => boolean;
/** True when --no-histdups removes duplicate history entries. */
export declare const optNoHistDups: () => boolean;
/** Mouse mode of --mouse (0 off, 1 on, 2 reverse). */
export declare const optMouse: () => number;
/** True when --rmouse (or --MOUSE) reverses the scroll direction. */
export declare const optMouseReverse: () => boolean;
/** True when --save-marks persists marks in the history file. */
export declare const optPermaMarks: () => boolean;
/** The -N line number field width (--line-num-width). */
export declare const optLinenumWidth: () => number;
/** The -J column width (--status-col-width). */
export declare const optStatusColWidth: () => number;
/** True when --incsearch searches as the pattern is typed. */
export declare const optIncrSearch: () => boolean;
/** The --header state: pinned lines, columns and 0-based start row. */
export declare const optHeader: () => {
    lines: number;
    cols: number;
    start: number;
};
/**
 * Re-anchors the header at the top of a newly opened file, like less's
 * edit_ifile calling set_header(ch_zero()).
 */
export declare function resetHeaderStart(): void;
/** The --no-search-header-* state: exclude header lines/columns. */
export declare const optNoSearchHeaders: () => {
    lines: boolean;
    cols: boolean;
};
/** True when --redraw-on-quit repaints the last screen at exit. */
export declare const optRedrawOnQuit: () => boolean;
/** True when --no-paste ignores bracketed paste input. */
export declare const optNoPaste: () => boolean;
/** True when --hilite-target highlights search/jump targets. */
export declare const optHiliteTarget: () => boolean;
/** True when --autosave includes an action char (or `*`). */
export declare const optAutosaveAction: (act: string) => boolean;
/** The --search-options default modifiers for a fresh search. */
export declare const optDefSearchType: () => typeof defSearchType;
/**
 * The --match-shift columns for the current screen width, like less's
 * calc_match_shift resolving a fraction (parts per million, rounded
 * like less's muldiv; the default fraction is half the width).
 */
export declare function optMatchShift(): number;
/** True when --emouse enables left-click mark setting. */
export declare const optEmouseLclick: () => boolean;
/** True when --emouse enables right-click mark jumping. */
export declare const optEmouseRclick: () => boolean;
/** True when --emouse (or --mouse) enables vertical wheel scrolling. */
export declare const optWheelEnabled: () => boolean;
/** True when --status-line highlights whole marked/attn lines. */
export declare const optStatusLine: () => boolean;
/** True when --form-feed stops scrolling at a \f line. */
export declare const optStopOnFormFeed: () => boolean;
/** True when --past-eof lets forward scrolls continue past (END). */
export declare const optPastEof: () => boolean;
/** The -u/-U backspace mode (0 special, 1 plain, 2 control). */
export declare const optBsMode: () => number;
/** The --proc-backspace state (0 default, 1 overstrike, 2 ^H). */
export declare const optProcBackspace: () => number;
/** The --proc-tab state (0 default, 1 expand, 2 ^I). */
export declare const optProcTab: () => number;
/** The --proc-return state (0 default, 1 delete at EOL, 2 ^M). */
export declare const optProcReturn: () => number;
/** True when --wordwrap breaks wrapped lines at spaces. */
export declare const optWordwrap: () => boolean;
/** True when -X suppresses the terminal init/deinit strings. */
export declare const optNoInit: () => boolean;
/** True when --no-keypad suppresses keypad mode. */
export declare const optNoKeypad: () => boolean;
/** True when --no-vbell suppresses the visual bell flash. */
export declare const optNoVbell: () => boolean;
/** True when --use-color enables the -D color map. */
export declare const optUseColor: () => boolean;
/** True when --use-js-regexp searches with the host RegExp instead of
 *  the POSIX engine less's regcomp would give. */
export declare const optUseJsRegexp: () => boolean;
/** The -T tags file name (or a GTAGS-family name). */
export declare const optTagsFile: () => string;
/** Resets -T to the "tags" default, for -T- once stdin is read. */
export declare const resetTagsFile: () => void;
/** True when -d suppresses the dumb terminal warning. */
export declare const optKnowDumb: () => boolean;
/** The --intr character that leaves the F wait (default ^X). */
export declare const optIntrChar: () => string;
/** True while $LESSOPEN preprocessing is enabled (-L turns it off). */
export declare const optUseLessopen: () => boolean;
/** True when --show-preproc-errors reports preprocessor failures. */
export declare const optShowPreprocError: () => boolean;
/** True when --no-edit-warn skips the LESSOPEN editing warning. */
export declare const optNoEditWarn: () => boolean;
/** True when interactive shell, pipe and editor commands are disabled. */
export declare const optNoShell: () => boolean;
/** less's deliberately terse error for an unavailable process escape. */
export declare const NO_SHELL_MESSAGE = "Command not available";
/** True when --follow-name makes F re-open the file by name. */
export declare const optFollowName: () => boolean;
/** True when --exit-follow-on-close ends F when the input closes. */
export declare const optExitFollowOnClose: () => boolean;
/** The --end-prompt string for the current prompt style, if any. */
export declare const optEndPrompt: () => string | null;
/** True when --old-bot clears the bottom line from lower-left, like
 *  less's clear_bot choosing lower_left over line_left. */
export declare const optOldBot: () => boolean;
/**
 * Scans the first --modelines lines for vim-style modelines, like
 * edit.c's check_modelines: only ts=/tabstop= settings are honored.
 */
export declare function checkModelines(lines: string[]): void;
/**
 * Adjusts a 1-based display line number for --no-number-headers, like
 * linenum.c's vlinenum: the header lines and everything above them get
 * no number (0), lines below the header restart at 1.
 */
export declare function vlinenum(linenum: number): number;
/** Applies --no-number-headers to an already absolute line number. */
export declare function vlinenumAbsolute(absolute: number): number;
export { fullScreenWidth } from "./state";
/** The -j target as a 0-based screen row for the current window. */
export declare function jumpSindex(): number;
/** The -# shift columns, resolving a fraction of the screen width
 *  like less's calc_shift_count; 0 means the half-screen default. */
export declare function optShiftCount(): number;
/**
 * Stores a numeric shift from an ESC-(/ESC-) count, clearing the -#
 * fraction like less's A_LSHIFT with a number.
 */
export declare function setShiftCount(count: number): void;
/**
 * Parses a number or a `.F` fraction, like optfunc.c's toggle_fraction
 * with getfraction: the fraction keeps six digits (parts per million).
 *
 * @returns The parsed value, or null after the less error message.
 */
export declare function parseFraction(text: string, printopt: string, negok: boolean): {
    num: number;
    frac: number;
} | null;
/**
 * Formats a value-or-fraction query, like optfunc.c's query_fraction
 * trimming trailing zeros down to two characters.
 */
export declare function queryFraction(value: number, frac: number, intMsg: string, fracMsg: string): string;
/** Lines per mouse wheel tick (--wheel-lines). */
export declare const optWheelLines: () => number;
/** Truncation marker character (--rscroll), empty when disabled. */
export declare const optRscroll: () => string;
/** The --rscroll fallback attribute codes when -D R sets no color,
 *  like less's rscroll_attr from setfmt's `*x` prefix. */
export declare function optRscrollAttr(): {
    on: string;
    off: string;
};
/**
 * True when displayed lines are truncated at the screen width: -S, or
 * any --header lines/columns, like less's chop_line().
 */
export declare const chopLine: () => boolean;
/**
 * The scroll window size, like less's get_swindow: a positive -z is the
 * size itself; zero or negative is relative to the screen height less
 * the --header lines (the default -1 leaves one line of overlap).
 */
export declare function getSwindow(): number;
/**
 * Returns the next tab stop after a column, like less's tabstops list:
 * explicit stops first, then every tabDefault columns.
 */
export declare function nextTabStop(col: number): number;
/**
 * Columns reserved at the left edge for the -J status column and the
 * -N line number field: less's NOMINAL width (line_pfx_width returns
 * linenum_width + 1, line.c:459) — a wider number overflows the
 * field and its LINE's text area shrinks instead (the line buffer
 * simply fills to sc_width past the actual prefix).
 */
export declare function gutterWidth(): number;
/**
 * Reserves the gutter inside a freshly measured screen width; call
 * right after config.screenWidth is set from the terminal size.
 */
export declare function reserveGutter(): void;
/**
 * Re-applies the gutter after a display option changed its width.
 */
export declare function applyGutter(content: string[]): void;
/** Registers the content pipeline rebuild used by -s, -x and -r. */
export declare function onRebuild(fn: () => void): void;
/**
 * Writes the mouse tracking codes for the current --mouse/--emouse
 * state.
 */
export declare function applyMouse(): void;
/**
 * Turns terminal bracketed paste markers on with --no-paste, so pasted
 * input can be recognized and ignored.
 */
export declare function applyBracketedPaste(): void;
/** Displays a control char like less's prchar (^X, ESC, ^?). */
export declare function prChar(char: string): string;
/**
 * Parses a comma-separated --emouse feature list, like decode.c's
 * parse_csl_bitmap: names prefix-match and combinations expand.
 *
 * Invalid/ambiguous members contribute no bits but do not stop the
 * list, matching csl_bitmap_bit returning zero to parse_csl_bitmap.
 */
export declare function parseEmouse(text: string): number;
/**
 * Builds the --emouse query list, like opt_emouse's QUERY greedily
 * naming combinations before their components.
 */
export declare function emouseNames(): string;
/**
 * Parses a --search-options answer, like opt_search_type: EFKNRW set
 * default modifiers, digits pick sub-patterns, `-` clears.
 */
export declare function setSearchType(text: string): void;
/** Formats the --search-options state, like opt_search_type QUERY. */
export declare function searchTypeNames(): string;
/**
 * Parses a --match-shift answer, like toggle_fraction with the `.d`
 * format: a leading `.` sets a fraction of the screen width, kept in
 * parts per million like less.
 */
export declare function setMatchShift(text: string): void;
export declare const CASELESS_MESSAGES: string[];
/**
 * Sets the header search exclusions, like optfunc.c's
 * do_nosearch_headers: the three options assign both flags rather than
 * toggling. Silent, so $LESS INIT matches less; toggles report through
 * noSearchHeadersMessage.
 */
export declare function setNoSearchHeaders(lines: number, cols: number): void;
export declare function noSearchHeadersMessage(): void;
/**
 * Recomputes the EOF anchor after a display-affecting toggle (-S).
 */
export declare function recalculateEOF(content: string[]): void;
/**
 * Parses the -x tab stop list, like less's set_tabs: a comma-separated
 * ascending list whose last interval repeats. Non-increasing entries
 * are skipped without ending the list, and fewer than two resulting
 * stops (counting the fixed leading 0) leave the old stops unchanged.
 */
export declare function setTabs(text: string): void;
/**
 * Reports a startup scan problem at the first prompt, like less's
 * error() calls before the screen initializes: follow-ups queue behind
 * the first message.
 */
export declare function optScanError(message: string): void;
/** Applies a command-line --header once content exists; the first
 *  display's jump clamps through after_header_pos, so the screen
 *  opens at the header start. */
export declare function applyPendingHeader(content: string[]): void;
export declare function setHeader(text: string, content: string[]): void;