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const std = @import("std");
const vaxis = @import("vaxis");
const pardes = @import("pardes.zig");
const layout = @import("layout.zig");
const config = @import("config.zig");
const Pardes = pardes.Pardes;
const modal = @import("modal.zig");
const filesystem = @import("fs.zig");
const syntax = @import("syntax.zig");
const tracy = @import("tracy.zig");
const dump = @import("dump.zig");
const limits = @import("memory.zig").limits;
const builtins = @import("builtins.zig");
const effect_sources = @import("effect_sources.zig");
const build_options = @import("pardes_config");
const lsp = @import("lsp/lsp.zig");
const image = @import("image.zig");
const look = @import("look.zig");
const locations = @import("locations.zig");
const Key = pardes.Key;

/// An owned editable buffer and the absolute surface row of its first line.
/// Files use row zero; terminal overlays may begin anywhere in scrollback.
pub const EditText = struct { text: []u8, row0: i32 };

pub const Pane = struct {
    pub const Mode = enum { normal, insert, tty };

    /// One mouse selection (block-shaped), per button. c/r are text-area relative;
    /// r counts from the tag row (body starts at BOX_H).
    pub const Sel = struct {
        state: enum { none, dragging, done } = .none,
        source_id: u64 = 0,
        c0: i32 = 0,
        c1: i32 = 0,
        r0: i32 = 0,
        r1: i32 = 0,
    };

    /// A rectangle keeps one source span per rendered row. Wrapped segments
    /// remain separate rows when copied, even when they share a source line.
    pub const PointerRow = struct {
        row: i32,
        lo: usize,
        hi: usize,
        prefix: [32]u8 = @splat(0),
        prefix_len: u8 = 0,
        raw_terminal: bool = false,
        prompt_bytes: usize = 0,
    };
    pub const PointerSelection = struct {
        gesture: Sel,
        rows: []PointerRow,
        raw_text: ?[]u8 = null,
    };

    /// A modal line selection (helix `x`): whole rows [r0, r1], absolute.
    pub const LineSel = struct {
        active: bool = false,
        r0: i32 = 0,
        r1: i32 = 0,
    };

    pub const CharSel = struct {
        active: bool = false,
        row: i32 = 0,
        col: i32 = 0,
        explicit: bool = false,
    };

    pub const LookSpot = struct {
        row: i32,
        col0: i32,
        col1: i32,
    };

    pub const max_selections = 64;

    pub const SelRange = struct {
        row: i32,
        col: i32,
        arow: i32,
        acol: i32,
        /// this range's own j/k goal column (helix Range::old_visual_position);
        /// the PRIMARY's copy is Pane.sticky_col
        sticky: i32 = -1,
    };

    const PdfSlot = if (Pdf.enabled) ?Pdf.State else void;

    pub const Prompt = union(enum) {
        none,
        search: u16,
        pipe: struct { at: u16, how: modal.Normal.PipeBehavior },
        /// Save on a scratch buffer or a terminal: the tail is a path to write to.
        save: u16,
        /// Del from the keyboard with open panes both above and below: which
        /// one takes the rows. Nothing is typed; one key answers.
        del_side,
    };

    pub const Cwd = union(enum) { none, inherited: *Pane, owned: []u8 };
    terminal: ?*Terminal.State = null,
    gpa: std.mem.Allocator,
    serial: u32 = 0,
    /// What the control filesystem keeps of this pane -- addr and limit, the
    /// event queue and its readers, a run waiting on the shell -- lives and
    /// dies with it, as acme keeps the same on its Window
    /// (editors/acme/dat.h:226-266).
    fs: pardes.ctlfs.pane.State = .{},
    mode: Mode = .normal,
    vweight: f32 = 1,
    /// A folded pane keeps its expansion weight, but occupies only its tag row.
    collapsed: bool = false,
    cols: u16,
    rows: u16,
    greet: bool = false,
    pending_command: Terminal.PendingCommand = .{},
    /// Native host queues the Linux v9fs launcher in this pane's initial shell.
    v9fs_on_spawn: bool = false,
    file: ?File.State = null,
    image: ?Image.State = null,
    pdf: PdfSlot = if (Pdf.enabled) null else {},
    msel: LineSel = .{},
    vsel: CharSel = .{},
    sels: [max_selections - 1]SelRange = undefined,
    nsel: u8 = 0,
    select: bool = false,
    /// sticky goal column for j/k runs (helix old_visual_position): any
    /// non-vertical range write resets it to -1.
    sticky_col: i32 = -1,
    append_at: ?struct { row: i32, col: i32 } = null,
    normal: modal.Normal.State = .{},
    /// last f/F/t/T motion, for Alt-. repeat
    find_op: u8 = 0,
    find_ch: u21 = 0,
    /// Tag-tail input state. The tag text is presentation; this tag carries
    /// which operation owns it and the tail offset restored on submit/cancel.
    prompt: Prompt = .none,
    search_pane: ?usize = null,
    search_row: ?usize = null,
    look_at: ?LookSpot = null,
    sel_snap: [max_selections]modal.Selection = undefined,
    nsel_snap: u8 = 0,
    sel_snap_pri: u8 = 0,
    sel_snap_expl: bool = false,
    /// the editable tag tail: a bounded one-line command buffer. Input that
    /// does not fit is refused atomically.
    tag_tail: [limits.max_tag_tail]u8 = undefined,
    tag_tail_len: usize = 0,
    tag_init: bool = false,
    tag_edit: bool = false,
    tag_sel: bool = false,
    /// the body mode a tag edit hijacked (tags are always insert); terminals
    /// restore it on exit so clicking the tag never changes the pane's mode
    tag_mode: Mode = .normal,
    tag_col: u16 = 0,
    tag_saved_col: ?u16 = null,
    tag_anchor: u16 = 0,
    /// Filename edits are staged separately from the live buffer identity.
    /// Enter commits the name; leaving tag editing discards the draft.
    tag_name: [limits.host_path_cap]u8 = undefined,
    tag_name_len: ?u16 = null,
    /// Display columns hidden to reveal the tag caret; tag addresses stay whole.
    tag_scroll: u16 = 0,
    ed_undo: [Terminal.history_max]Terminal.Snapshot = undefined,
    ed_undo_len: usize = 0,
    ed_redo: [Terminal.history_max]Terminal.Snapshot = undefined,
    ed_redo_len: usize = 0,
    cwd: Cwd = .none,
    cur_pinned: bool = false,
    cur_row: i32 = 0,
    cur_col: i32 = 0,
    hscroll: i32 = 0,
    // Visible rows map to source lines and raw/display column origins.
    wrap_line: [limits.wrap_rows]i32 = undefined,
    wrap_col: [limits.wrap_rows]i32 = undefined,
    wrap_n: u16 = 0,
    /// A row map also exists for sticky headers when soft wrapping is off.
    body_wrapped: bool = false,
    context_rows: u16 = 0,
    body_rows: u16 = 0,
    body_visible_rows: u16 = 0,
    context_row_limit: ?u16 = null,
    sel: [3]Sel = @splat(.{}),
    pointer_selections: [3]?PointerSelection = @splat(null),
    next_pointer_selection: u64 = 0,

    /// terminals only: the typed-text buffer standing in for shell rows
    ovl: ?Terminal.EditBuffer = null,
    tty_filter: bool = false,
    msg: [256]u8 = undefined,
    msg_len: u16 = 0,
    /// Where the newest message line is in its life.
    msg_life: MessageLife = .{},
    /// The row (among the notice rows) the newest line holds for its life.
    msg_slot: u8 = 0,
    /// Earlier message lines still on screen, oldest first, each running its
    /// own life: a new message stacks under them instead of replacing them.
    msg_older: [message_stack]OlderMessage = undefined,
    msg_older_len: u8 = 0,
    /// The newest line is a builtin announcing itself in this step: what
    /// the step says next replaces it rather than stacking under it.
    msg_announcement: bool = false,
    /// The newest line is a status (progress, a server's state): the next
    /// line replaces it rather than stacking under it.
    msg_status: bool = false,
    /// The transient lines this pane shows between its body and its tagline:
    /// a builtin's message, the pending leader chord, a prompt waiting for
    /// input. Rebuilt every frame from the state that owns each one, so a
    /// line that goes away is simply not added again and the rest close the
    /// gap -- there is no second copy of the truth to fall out of step. The
    /// body layer reserves exactly `len` rows for them, the way it already
    /// reserves rows for sticky context headers.
    notices: Notices = .{},

    pub const MessagePhase = enum { entering, shown, lingering, leaving };
    /// One message line's animation: falling in, shown, lingering after the
    /// key or click that dismissed it, dissolving. `frame` counts animation
    /// frames within the phase.
    pub const MessageLife = struct {
        phase: MessagePhase = .shown,
        frame: u16 = 0,
        /// Dismissed while still falling: it lingers once it has landed.
        dismissed: bool = false,
    };
    /// Older message lines kept on screen under a new one.
    pub const message_stack = 3;
    pub const OlderMessage = struct {
        text: [256]u8 = undefined,
        len: u16 = 0,
        life: MessageLife = .{},
        slot: u8 = 0,

        pub fn slice(line: *const OlderMessage) []const u8 {
            return line.text[0..line.len];
        }
    };

    /// Move the newest line onto the stack of older ones, dropping the oldest
    /// when it is full; the newest slot is left empty for what arrives.
    pub fn pushOlderMessage(pane: *Pane) void {
        if (pane.msg_older_len == message_stack) {
            std.mem.copyForwards(OlderMessage, pane.msg_older[0 .. message_stack - 1], pane.msg_older[1..]);
            pane.msg_older_len -= 1;
        }
        pane.msg_older[pane.msg_older_len] = .{ .text = pane.msg, .len = pane.msg_len, .life = pane.msg_life, .slot = pane.msg_slot };
        pane.msg_older_len += 1;
        pane.msg_len = 0;
        pane.msg_life = .{};
    }

    /// The first row no older line holds. A line keeps its row until it
    /// leaves, and a new one fills the first gap: nothing on screen moves.
    pub fn freeMessageSlot(pane: *const Pane) u8 {
        var used: u8 = 0;
        for (pane.msg_older[0..pane.msg_older_len]) |line| used |= @as(u8, 1) << @intCast(line.slot);
        var slot: u8 = 0;
        while (used & (@as(u8, 1) << @intCast(slot)) != 0) slot += 1;
        return slot;
    }

    pub fn removeOlderMessage(pane: *Pane, i: usize) void {
        std.mem.copyForwards(OlderMessage, pane.msg_older[i .. pane.msg_older_len - 1], pane.msg_older[i + 1 .. pane.msg_older_len]);
        pane.msg_older_len -= 1;
    }

    pub const Notices = struct {
        /// Painted bottom-up in this order, so a prompt keeps the row nearest
        /// the tagline that it has always had, and its cursor with it.
        /// `older` is an earlier message line still on screen; `index` says
        /// which (`Pane.msg_older`).
        pub const Kind = enum { older, message, leader, prompt };
        pub const max = @typeInfo(Kind).@"enum".fields.len - 1 + message_stack;

        kinds: [max]Kind = undefined,
        index: [max]u8 = @splat(0),
        /// Each band's row below the body's top: message lines keep theirs,
        /// so a band that leaves leaves a gap rather than moving the rest.
        row: [max]u8 = @splat(0),
        /// Where each band's chip starts, as an absolute grid column. A chip
        /// is only as wide as its own text, so the rest of the row underneath
        /// is ordinary body text and a click there has to reach it.
        left: [max]u16 = @splat(std.math.maxInt(u16)),
        len: u8 = 0,

        /// A band on the next row after every band so far.
        pub fn push(n: *Notices, kind: Kind) void {
            n.pushAt(kind, 0, n.span());
        }

        pub fn pushAt(n: *Notices, kind: Kind, index: u8, row: u8) void {
            if (n.len >= max) return;
            n.kinds[n.len] = kind;
            n.index[n.len] = index;
            n.row[n.len] = row;
            n.left[n.len] = std.math.maxInt(u16);
            n.len += 1;
        }

        /// Is this cell inside the chip drawn for band `i`? Nothing else on
        /// that row belongs to the notice.
        pub fn covers(n: *const Notices, row: usize, col: u16) bool {
            for (0..n.len) |i| if (n.row[i] == row) return col >= n.left[i];
            return false;
        }

        /// Rows from the body's top down to the last band's.
        pub fn span(n: *const Notices) u8 {
            var rows: u8 = 0;
            for (n.row[0..n.len]) |row| rows = @max(rows, row + 1);
            return rows;
        }

        pub fn slice(n: *const Notices) []const Kind {
            return n.kinds[0..n.len];
        }
    };

    pub fn clearPointerSelection(pane: *Pane, slot: usize) void {
        if (pane.pointer_selections[slot]) |selection| {
            pane.gpa.free(selection.rows);
            if (selection.raw_text) |text| pane.gpa.free(text);
        }
        pane.pointer_selections[slot] = null;
    }

    pub fn rawPointerText(pane: *const Pane, gesture: Sel) ?[]const u8 {
        if (gesture.state != .done or gesture.source_id == 0) return null;
        for (pane.pointer_selections) |selection| {
            if (selection) |saved| if (std.meta.eql(saved.gesture, gesture)) return saved.raw_text;
        }
        return null;
    }

    pub fn pointerSelection(pane: *const Pane, gesture: Sel) ?[]PointerRow {
        if (gesture.state != .done or gesture.source_id == 0) return null;
        for (pane.pointer_selections) |selection| {
            if (selection) |saved| if (std.meta.eql(saved.gesture, gesture)) return saved.rows;
        }
        return null;
    }

    pub fn tagSlice(p: *const Pane) []const u8 {
        return p.tag_tail[0..p.tag_tail_len];
    }
    pub fn promptAt(p: *const Pane) ?u16 {
        return switch (p.prompt) {
            .none, .del_side => null,
            .search, .save => |at| at,
            .pipe => |pipe| pipe.at,
        };
    }

    /// What an open prompt shows on its notice band: the one answer every
    /// painter of the band reads.
    pub fn promptText(p: *const Pane) ?[]const u8 {
        if (p.prompt == .del_side) return config.del_question;
        const at = p.promptAt() orelse return null;
        return p.tagSlice()[@min(at, p.tag_tail_len)..];
    }

    pub fn appendTag(p: *Pane, text: []const u8) bool {
        if (text.len > p.tag_tail.len - p.tag_tail_len) return false;
        @memcpy(p.tag_tail[p.tag_tail_len..][0..text.len], text);
        p.tag_tail_len += text.len;
        return true;
    }

    pub fn insertTagByte(p: *Pane, at: usize, byte: u8) bool {
        if (at > p.tag_tail_len or p.tag_tail_len == p.tag_tail.len) return false;
        std.mem.copyBackwards(u8, p.tag_tail[at + 1 .. p.tag_tail_len + 1], p.tag_tail[at..p.tag_tail_len]);
        p.tag_tail[at] = byte;
        p.tag_tail_len += 1;
        return true;
    }

    pub fn removeTagByte(p: *Pane, at: usize) void {
        if (at >= p.tag_tail_len) return;
        std.mem.copyForwards(u8, p.tag_tail[at .. p.tag_tail_len - 1], p.tag_tail[at + 1 .. p.tag_tail_len]);
        p.tag_tail_len -= 1;
    }

    pub fn cwdSlice(p: *const Pane) []const u8 {
        return switch (p.cwd) {
            .none => "",
            .owned => |dir| dir,
            .inherited => |src| src.cwdSlice(),
        };
    }

    pub fn clearCwd(pane: *Pane) void {
        if (pane.cwd == .owned) pane.gpa.free(pane.cwd.owned);
        pane.cwd = .none;
    }

    pub fn setOwnedCwd(pane: *Pane, dir: []const u8) !void {
        if (dir.len > limits.host_path_cap) return error.PathTooLong;
        const copy = try pane.gpa.dupe(u8, dir);
        pane.clearCwd();
        pane.cwd = .{ .owned = copy };
    }

    pub fn isTerminal(pane: *const Pane) bool {
        const no_pdf = if (comptime Pdf.enabled) pane.pdf == null else true;
        return pane.file == null and pane.image == null and no_pdf;
    }

    /// The one coloring choice keyed on what a pane IS, so the highlight
    /// producer (refreshHighlights) and the render pass agree on the algorithm.
    pub const ColorAlgo = enum { none, tty, source, diff, locations };
    pub fn colorAlgo(pane: *const Pane) ColorAlgo {
        if (pane.isTerminal()) return .tty;
        if (pane.file) |f| {
            if (f.mini != null) return .source;
            if (std.mem.endsWith(u8, f.path, ".diff") or std.mem.endsWith(u8, f.path, ".patch")) return .diff;
            if (f.output != null) {
                const tr = Output.fileTraits(f.output);
                if (tr.locations) return .locations;
                if (!tr.saves) return .none;
            }
            return .source;
        }
        return .none;
    }

    pub fn pdfPath(pane: *const Pane) ?[]const u8 {
        if (comptime Pdf.enabled) if (pane.pdf) |pv| return pv.path;
        return null;
    }

    pub fn pdfPage(pane: *const Pane) ?usize {
        if (comptime Pdf.enabled) if (pane.pdf) |pv| return pv.page;
        return null;
    }

    pub fn surfRow(pane: *const Pane, g: i32) i32 {
        const o = pane.ovl orelse return g;
        if (g <= o.row) return g;
        const lines: i32 = @intCast(modal.lineCount(o.text));
        if (g >= o.row + o.rows) return g + lines - o.rows;
        return @min(g, o.row + lines - 1); // inside the buffer: its own rows
    }

    /// the inverse; every surface row inside the edit buffer maps to its anchor
    pub fn gridRow(pane: *const Pane, s: i32) i32 {
        const o = pane.ovl orelse return s;
        if (s <= o.row) return s;
        const lines: i32 = @intCast(modal.lineCount(o.text));
        if (s < o.row + lines) return o.row;
        return s - lines + o.rows;
    }

    /// current scroll offset: file top line, or the scrollback offset
    pub fn scroll(pane: *Pane) i32 {
        if (pane.file) |f| return @intCast(f.scroll);
        if (comptime Pdf.enabled) if (pane.pdf) |pv| return @intCast(pv.text_scroll);
        return pane.surfRow(Terminal.gridOffset(pane));
    }

    pub fn wrapAt(pane: *Pane, vr: i32) struct { line: i32, at: i32 } {
        if (pane.wrap_n > 0 and vr >= 0 and vr < @as(i32, pane.wrap_n))
            return .{ .line = pane.wrap_line[@intCast(vr)], .at = pane.wrap_col[@intCast(vr)] };
        // unwrapped: rows ARE lines, and the byte column a row starts at is the
        // horizontal scroll (always 0 on a terminal, which never has one)
        return .{ .line = pane.scroll() + vr, .at = pane.hscroll };
    }

    pub fn wrapRow(pane: *Pane, line: i32, col: i32) struct { row: i32, at: i32 } {
        if (pane.wrap_n == 0) return .{ .row = line - pane.scroll(), .at = pane.hscroll };
        var i: u16 = 0;
        while (i < pane.wrap_n) : (i += 1) {
            if (pane.wrap_line[i] != line) continue;
            // the LAST row of a line owns every column past its start, so a
            // cursor parked on the trailing newline still has somewhere to draw
            if (i + 1 < pane.wrap_n and pane.wrap_line[i + 1] == line and col >= pane.wrap_col[i + 1]) continue;
            return .{ .row = @intCast(i), .at = pane.wrap_col[i] };
        }
        return .{ .row = -1, .at = 0 };
    }

    pub fn scrollBy(pane: *Pane, delta: i32) void {
        if (pane.file) |*f| {
            const max: i64 = @intCast(File.nlines(pane.gpa, f) -| 1);
            const n = std.math.clamp(@as(i64, @intCast(f.scroll)) + delta, 0, max);
            const next: usize = @intCast(n);
            if (next != f.scroll) {
                f.scroll = next;
                f.syntax_dirty = true;
            }
        } else if (hasPdf(pane)) {
            if (comptime Pdf.enabled) {
                const pv = &pane.pdf.?;
                const max: i64 = @intCast(modal.lineCount(pv.text) -| 1);
                pv.text_scroll = @intCast(std.math.clamp(
                    @as(i64, @intCast(pv.text_scroll)) + delta,
                    0,
                    max,
                ));
            }
        } else {
            // the vt scrolls in SHELL rows; convert through the edit buffer
            const off = Terminal.gridOffset(pane);
            Terminal.scrollGrid(pane, pane.gridRow(pane.surfRow(off) + delta) - off);
        }
    }

    pub fn ensureCursorVisible(pane: *Pane) void {
        const off = pane.scroll();
        var in_context = false;
        // Maps survive until the next render. A jump may have changed scroll
        // already, so only treat an ancestor as pinned in the matching view.
        if (pane.context_rows < pane.wrap_n and pane.wrap_line[pane.context_rows] == off) {
            for (pane.wrap_line[0..pane.context_rows]) |row| {
                if (row == pane.cur_row) {
                    in_context = true;
                    break;
                }
            }
        }
        // Scrolloff is measured in the ordinary body, excluding sticky rows.
        var margin: i32 = @min(config.scroll_off, @divTrunc(@as(i32, pane.rows) - 1, 2));
        var last = off + @as(i32, pane.rows) - 1;
        const visible_rows = if (pane.body_visible_rows > 0) @min(pane.wrap_n, pane.body_visible_rows) else pane.wrap_n;
        if (pane.context_rows < visible_rows) {
            const lines_shown = pane.wrap_line[visible_rows - 1] - pane.wrap_line[pane.context_rows];
            last = off + lines_shown;
            margin = @min(margin, @divTrunc(@max(0, lines_shown), 2));
        }
        if (!in_context) {
            if (pane.cur_row < off + margin) {
                pane.scrollBy(pane.cur_row - margin - off);
            } else if (pane.cur_row > last - margin) {
                var to = pane.cur_row + margin;
                if (pane.file) |*f| to = @min(to, @as(i32, @intCast(File.nlines(pane.gpa, f) -| 1)));
                if (comptime Pdf.enabled) {
                    if (pane.pdf) |pv|
                        to = @min(to, @as(i32, @intCast(modal.lineCount(pv.text) -| 1)));
                }
                pane.scrollBy(@max(0, to - last));
            }
        }
        if (pane.file) |f| {
            if (pane.body_wrapped) return;
            const w: i32 = @max(1, @as(i32, pane.cols) - @as(i32, File.gutterWidth(pane)));
            const hmargin: i32 = @min(config.scroll_off, @divTrunc(w - 1, 2));
            const line = modal.lineSlice(f.content, @intCast(@max(0, pane.cur_row)));
            const raw_cur: usize = @intCast(@max(0, pane.cur_col));
            const raw_scroll: usize = @intCast(@max(0, pane.hscroll));
            const cur = @as(i32, @intCast(File.rawDisplayCol(line, raw_cur)));
            const visual_scroll = @as(i32, @intCast(File.rawDisplayCol(line, raw_scroll)));
            var target = visual_scroll;
            if (cur < visual_scroll + hmargin)
                target = @max(0, cur - hmargin)
            else if (cur > visual_scroll + w - 1 - hmargin)
                target = cur - (w - 1 - hmargin);
            if (target != visual_scroll) pane.hscroll = @intCast(File.rawAtDisplay(line, @intCast(target)));
        }
    }

    pub fn pinCursor(pane: *Pane) void {
        if (pane.cur_pinned) return;
        if (pane.file != null or hasPdf(pane)) {
            pane.cur_row = pane.scroll();
            pane.cur_col = 0;
        } else {
            const cur = Terminal.gridCursor(pane);
            pane.cur_row = pane.surfRow(@as(i32, cur.y) + Terminal.gridOffset(pane));
            pane.cur_col = @intCast(cur.x);
        }
        pane.cur_pinned = true;
    }

    pub fn hasPdf(pane: *const Pane) bool {
        return if (comptime Pdf.enabled) pane.pdf != null else false;
    }

    pub fn hasPdfSelection(pane: *const Pane) bool {
        return if (comptime Pdf.enabled)
            if (pane.pdf) |pv| pv.selection != null and pv.selection_text.len > 0 else false
        else
            false;
    }

    pub fn toModalCursor(pane: *Pane) modal.Cursor {
        return .{ .row = @intCast(@max(0, pane.cur_row)), .col = @intCast(@max(0, pane.cur_col)) };
    }

    pub fn fromModalCursor(pane: *Pane, c: modal.Cursor) void {
        pane.cur_row = @as(i32, @intCast(c.row));
        pane.cur_col = @intCast(c.col);
        pane.cur_pinned = true;
    }

    pub fn insertVerticalCursor(lines: []const []const u8, c: modal.Cursor, down: bool) modal.Cursor {
        if (lines.len == 0) return c;
        const row = if (down) @min(c.row + 1, lines.len - 1) else c.row -| 1;
        const target = lines[row];
        if (target.len == 0) return .{ .row = row, .col = 0 };
        const source = if (c.row < lines.len) lines[c.row] else "";
        const goal = File.rawDisplayCol(source, c.col);
        const mapped = File.rawAtDisplay(target, goal);
        const last = modal.prevGrapheme(target, target.len);
        return .{ .row = row, .col = modal.graphemeStart(target, @min(mapped, last)) };
    }

    pub fn primaryRange(pane: *Pane, text: []const u8, row0: i32) modal.Selection {
        const c = File.textOffset(pane, text, .{ .row = @intCast(@max(0, pane.cur_row - row0)), .col = @intCast(@max(0, pane.cur_col)) });
        if (pane.msel.active) {
            // legacy line selection (file-search results highlight): linewise
            const r0: usize = @intCast(@max(0, @min(pane.msel.r0, pane.msel.r1) - row0));
            const r1: usize = @intCast(@max(0, @max(pane.msel.r0, pane.msel.r1) - row0));
            const s = modal.lineStartOffset(text, r0);
            const e = if (r1 + 1 >= modal.cursorLineCount(text)) text.len else modal.lineStartOffset(text, r1 + 1);
            return .{ .anchor = s, .head = @max(e, modal.nextGrapheme(text, c)) };
        }
        if (pane.vsel.active) return cellRange(text, pane.vsel.row - row0, pane.vsel.col, pane.cur_row - row0, pane.cur_col);
        return .{ .anchor = c, .head = modal.nextGrapheme(text, c) };
    }

    pub fn cellRange(text: []const u8, arow: i32, acol: i32, hrow: i32, hcol: i32) modal.Selection {
        const a = modal.offsetAt(text, .{ .row = @intCast(@max(0, arow)), .col = @intCast(@max(0, acol)) });
        const c = modal.offsetAt(text, .{ .row = @intCast(@max(0, hrow)), .col = @intCast(@max(0, hcol)) });
        return cellOffRange(text, a, c);
    }

    /// the same, from the two cells' gap offsets
    pub fn cellOffRange(text: []const u8, a: usize, c: usize) modal.Selection {
        if (a <= c) return .{ .anchor = a, .head = modal.nextGrapheme(text, c) };
        return .{ .anchor = modal.nextGrapheme(text, a), .head = c };
    }

    pub fn rangeCells(text: []const u8, r: modal.Selection) struct { cur: usize, anc: usize } {
        if (r.head > r.anchor) return .{ .cur = modal.prevGrapheme(text, r.head), .anc = r.anchor };
        if (r.head < r.anchor) return .{ .cur = r.head, .anc = modal.prevGrapheme(text, r.anchor) };
        return .{ .cur = r.head, .anc = r.head };
    }

    pub fn setRange(pane: *Pane, text: []const u8, row0: i32, r0: modal.Selection, explicit: bool) void {
        var r = r0;
        if (r.anchor == r.head) r.head = modal.nextGrapheme(text, r.head); // min_width_1
        const off = rangeCells(text, r);
        const cc = File.textPosition(pane, text, off.cur);
        // a bare block cursor has both cells on the same offset — the common
        // case by far — and this conversion is not free even indexed
        const ac = if (off.anc == off.cur) cc else File.textPosition(pane, text, off.anc);
        pane.cur_row = @as(i32, @intCast(cc.row)) + row0;
        pane.cur_col = @intCast(cc.col);
        pane.vsel = .{
            .active = off.anc != off.cur or pane.select,
            .row = @as(i32, @intCast(ac.row)) + row0,
            .col = @intCast(ac.col),
            .explicit = explicit or pane.select,
        };
        pane.msel.active = false;
        pane.nsel = 0; // writing ONE range means the selection IS that range
        pane.cur_pinned = true;
        pane.sticky_col = -1;
        pane.normal.clear();
        pane.ensureCursorVisible();
    }

    pub fn ranges(pane: *Pane, text: []const u8, row0: i32, out: *[max_selections]modal.Selection) struct { n: usize, pri: usize } {
        const pr = primaryRange(pane, text, row0);
        var n: usize = 0;
        var pri: usize = 0;
        var placed = false;
        for (pane.sels[0..pane.nsel]) |s| {
            const r = cellRange(text, s.arow - row0, s.acol, s.row - row0, s.col);
            if (!placed and @min(pr.anchor, pr.head) <= @min(r.anchor, r.head)) {
                pri = n;
                out[n] = pr;
                n += 1;
                placed = true;
            }
            out[n] = r;
            n += 1;
        }
        if (!placed) {
            pri = n;
            out[n] = pr;
            n += 1;
        }
        return .{ .n = n, .pri = pri };
    }

    pub fn setRanges(pane: *Pane, text: []const u8, in: []const modal.Selection, sticky: []const i32, pri0: usize, explicit: bool) void {
        if (in.len == 0) return; // helix asserts non-empty; here it just means "no change"
        var r: [max_selections]modal.Selection = undefined;
        var st: [max_selections]i32 = undefined;
        var n: usize = @min(in.len, max_selections);
        var pri: usize = @min(pri0, n - 1);
        for (in[0..n], 0..) |x, i| {
            r[i] = x;
            if (r[i].anchor == r[i].head) r[i].head = modal.nextGrapheme(text, r[i].head);
            st[i] = if (i < sticky.len) sticky[i] else -1;
        }
        // insertion sort by start — n is tiny and usually already ordered
        var i: usize = 1;
        while (i < n) : (i += 1) {
            var j = i;
            while (j > 0 and @min(r[j].anchor, r[j].head) < @min(r[j - 1].anchor, r[j - 1].head)) : (j -= 1) {
                std.mem.swap(modal.Selection, &r[j], &r[j - 1]);
                std.mem.swap(i32, &st[j], &st[j - 1]);
                if (pri == j) pri = j - 1 else if (pri == j - 1) pri = j;
            }
        }
        var k: usize = 0;
        i = 1;
        while (i < n) : (i += 1) {
            const a = r[k];
            const b = r[i];
            const af = @min(a.anchor, a.head);
            const at = @max(a.anchor, a.head);
            const bf = @min(b.anchor, b.head);
            const bt = @max(b.anchor, b.head);
            if (af == bf or (at > bf and bt > af)) {
                r[k] = if (a.anchor > a.head and b.anchor > b.head)
                    .{ .anchor = @max(a.anchor, b.anchor), .head = @min(a.head, b.head) }
                else
                    .{ .anchor = @min(af, bf), .head = @max(at, bt) };
                if (pri == i) pri = k;
                if (st[k] < 0) st[k] = st[i];
                continue;
            }
            k += 1;
            r[k] = b;
            st[k] = st[i];
            if (pri == i) pri = k;
        }
        n = k + 1;
        setRange(pane, text, 0, r[pri], explicit);
        pane.sticky_col = st[pri];
        var w: usize = 0;
        for (r[0..n], 0..) |x, idx| {
            if (idx == pri) continue;
            const c = rangeCells(text, x);
            const cc = modal.positionAt(text, c.cur);
            const ac = modal.positionAt(text, c.anc);
            pane.sels[w] = .{
                .row = @as(i32, @intCast(cc.row)),
                .col = @intCast(cc.col),
                .arow = @as(i32, @intCast(ac.row)),
                .acol = @intCast(ac.col),
                .sticky = st[idx],
            };
            w += 1;
        }
        pane.nsel = @intCast(w);
    }

    pub fn multiSelAction(pane: *Pane, text: []const u8, kind: modal.Normal.Multi, cnt: usize) void {
        var rs: [max_selections]modal.Selection = undefined;
        const got = ranges(pane, text, 0, &rs);
        const n = got.n;
        const expl = (pane.vsel.active and pane.vsel.explicit) or pane.msel.active;
        if (kind == .remove_primary) {
            if (n < 2) return; // helix: "no selections remaining"
            var out: [max_selections]modal.Selection = undefined;
            var m: usize = 0;
            for (rs[0..n], 0..) |r, i| {
                if (i == got.pri) continue;
                out[m] = r;
                m += 1;
            }
            // helix Selection::remove: the NEXT range takes over, or the
            // previous one when the primary was last
            return setRanges(pane, text, out[0..m], &.{}, @min(got.pri, m - 1), expl);
        }
        if (kind == .rotate_forward or kind == .rotate_backward) {
            const step = cnt % n;
            const pri = if (kind == .rotate_forward) (got.pri + step) % n else (got.pri + (n - step)) % n;
            return setRanges(pane, text, rs[0..n], &.{}, pri, expl);
        }
        if (kind == .merge) {
            // helix merge_selections: first.merge(last) — the ranges are
            // sorted, so that is simply the whole span
            const lo = @min(rs[0].anchor, rs[0].head);
            const hi = @max(rs[n - 1].anchor, rs[n - 1].head);
            const rev = rs[0].anchor > rs[0].head and rs[n - 1].anchor > rs[n - 1].head;
            const one: modal.Selection = if (rev) .{ .anchor = hi, .head = lo } else .{ .anchor = lo, .head = hi };
            return setRanges(pane, text, &.{one}, &.{}, 0, expl);
        }
        if (kind == .merge_consecutive) {
            var out: [max_selections]modal.Selection = undefined;
            var m: usize = 0;
            var pri: usize = 0;
            for (rs[0..n], 0..) |r, i| {
                if (m > 0 and @min(r.anchor, r.head) == @max(out[m - 1].anchor, out[m - 1].head)) {
                    const lo = @min(@min(out[m - 1].anchor, out[m - 1].head), @min(r.anchor, r.head));
                    const hi = @max(@max(out[m - 1].anchor, out[m - 1].head), @max(r.anchor, r.head));
                    out[m - 1] = .{ .anchor = lo, .head = hi };
                    if (i == got.pri) pri = m - 1;
                    continue;
                }
                if (i == got.pri) pri = m;
                out[m] = r;
                m += 1;
            }
            return setRanges(pane, text, out[0..m], &.{}, pri, expl);
        }
        if (kind == .split_newline) {
            // helix selection::split_on_newline — one range per line the
            // selection covers, the newlines themselves left out
            var out: [max_selections]modal.Selection = undefined;
            var m: usize = 0;
            for (rs[0..n]) |r| {
                const from = @min(r.anchor, r.head);
                const to = @max(r.anchor, r.head);
                if (from == to) {
                    if (m < max_selections) {
                        out[m] = r;
                        m += 1;
                    }
                    continue;
                }
                var start = from;
                while (start < to and m < max_selections) {
                    const eol = modal.lineEndOffset(text, modal.lineAtOffset(text, start));
                    if (eol >= to) {
                        out[m] = .{ .anchor = start, .head = to };
                        m += 1;
                        break;
                    }
                    out[m] = .{ .anchor = start, .head = eol };
                    m += 1;
                    start = eol + 1;
                }
            }
            if (m == 0) return;
            return setRanges(pane, text, out[0..m], &.{}, 0, true); // helix keeps primary 0
        }
        if (kind == .trim) {
            // helix trim_selections: whitespace off both ends; ranges that are
            // empty or all whitespace are dropped entirely
            var out: [max_selections]modal.Selection = undefined;
            var m: usize = 0;
            for (rs[0..n]) |r| {
                var from = @min(r.anchor, r.head);
                var to = @max(r.anchor, r.head);
                while (from < to and std.ascii.isWhitespace(text[from])) from += 1;
                while (to > from and std.ascii.isWhitespace(text[to - 1])) to -= 1;
                if (from >= to) continue;
                out[m] = if (r.anchor > r.head) .{ .anchor = to, .head = from } else .{ .anchor = from, .head = to };
                m += 1;
            }
            if (m == 0) { // helix: collapse_selection + keep_primary_selection
                const c = modal.selectionCursor(text, rs[got.pri]);
                return setRange(pane, text, 0, .{ .anchor = c, .head = c }, false);
            }
            // helix: the first survivor that OVERLAPS the old primary, else the last
            const pf = @min(rs[got.pri].anchor, rs[got.pri].head);
            const pt = @max(rs[got.pri].anchor, rs[got.pri].head);
            var pri = m - 1;
            for (out[0..m], 0..) |r, i| {
                const f = @min(r.anchor, r.head);
                const t = @max(r.anchor, r.head);
                if (f == pf or (t > pf and pt > f)) {
                    pri = i;
                    break;
                }
            }
            return setRanges(pane, text, out[0..m], &.{}, pri, expl);
        }
        const below = kind == .copy_below;
        var out: [max_selections]modal.Selection = undefined;
        var m: usize = 0;
        var pri: usize = 0;
        const nlines = modal.cursorLineCount(text);
        for (rs[0..n], 0..) |r, ri| {
            const is_pri = ri == got.pri;
            // head-exclusive: back the leading end off onto its own cell
            const hp = modal.positionAt(text, if (r.anchor < r.head) modal.prevGrapheme(text, r.head) else r.head);
            const ap = modal.positionAt(text, if (r.anchor < r.head) r.anchor else modal.prevGrapheme(text, r.anchor));
            const height = @max(hp.row, ap.row) - @min(hp.row, ap.row) + 1;
            if (m >= max_selections) break;
            if (is_pri) pri = m;
            out[m] = r;
            m += 1;
            var made: usize = 0;
            var k: usize = 0;
            while (made < cnt and m < max_selections) : (k += 1) {
                const d = (k + 1) * height;
                const arow = if (below) ap.row + d else ap.row -| d;
                const hrow = if (below) hp.row + d else hp.row -| d;
                if (arow >= nlines or hrow >= nlines) break;
                const a2 = modal.offsetAt(text, .{ .row = arow, .col = ap.col });
                const h2 = modal.offsetAt(text, .{ .row = hrow, .col = hp.col });
                // a line too short to reach the column is skipped, not clamped
                if (modal.positionAt(text, a2).col == ap.col and modal.positionAt(text, h2).col == hp.col) {
                    if (is_pri) pri = m;
                    out[m] = modal.moveSelectionCursor(text, .{ .anchor = a2, .head = a2 }, h2, true);
                    m += 1;
                    made += 1;
                }
                if (arow == 0 and hrow == 0) break;
            }
        }
        setRanges(pane, text, out[0..m], &.{}, pri, expl);
    }

    /// a range's start CELL (document order key) — the smaller of its two ends
    pub fn selStart(s: SelRange) struct { row: i32, col: i32 } {
        if (s.arow < s.row or (s.arow == s.row and s.acol < s.col)) return .{ .row = s.arow, .col = s.acol };
        return .{ .row = s.row, .col = s.col };
    }

    pub fn maxLine(text: []const u8) usize {
        const nl = modal.cursorLineCount(text);
        return if (text.len == 0 or text[text.len - 1] == '\n') nl -| 2 else nl - 1;
    }

    /// point-target motion: collapse there (extend in select mode)
    pub fn pointMove(pane: *Pane, text: []const u8, range: modal.Selection, target: usize) void {
        setRange(pane, text, 0, modal.moveSelectionCursor(text, range, target, pane.select), false);
    }

    /// word motions select their traversed span (extend mode: head only)
    pub fn wordMove(pane: *Pane, text: []const u8, range: modal.Selection, cnt: usize, target: modal.WordTarget) void {
        const wr = modal.moveWord(text, range, cnt, target);
        const res = if (pane.select) modal.moveSelectionCursor(text, range, modal.selectionCursor(text, wr), true) else wr;
        setRange(pane, text, 0, res, false);
    }

    /// f/t/F/T: anchor at the old cursor cell, head on the hit (not found: no move)
    pub fn findMove(pane: *Pane, text: []const u8, range: modal.Selection, ch: u21, fwd: bool, till: bool, cnt: usize) void {
        const cur = modal.selectionCursor(text, range);
        const t = modal.findTarget(text, cur, ch, fwd, till, cnt) orelse return;
        const res = if (pane.select)
            modal.moveSelectionCursor(text, range, t, true)
        else
            modal.moveSelectionCursor(text, .{ .anchor = cur, .head = cur }, t, true);
        setRange(pane, text, 0, res, false);
    }

    /// j/k and friends: sticky goal column, clamped onto short lines' newline
    pub fn verticalMove(pane: *Pane, text: []const u8, range: modal.Selection, down: bool, cnt: usize) void {
        const cur = modal.selectionCursor(text, range);
        const pos = File.textPosition(pane, text, cur);
        const goal: usize = if (pane.sticky_col >= 0)
            @intCast(pane.sticky_col)
        else
            File.rawDisplayCol(File.textLine(pane, text, pos.row), pos.col);
        const last_row = File.textLineCount(pane, text) - 1;
        const nline = if (down) @min(pos.row + @max(1, cnt), last_row) else pos.row -| @max(1, cnt);
        const target_col = File.rawAtDisplay(File.textLine(pane, text, nline), goal);
        const t = File.textOffset(pane, text, .{ .row = nline, .col = target_col });
        // extend mode never walks onto the empty trailing line (helix)
        if (pane.select and t == text.len and text.len > 0 and text[text.len - 1] == '\n') return;
        setRange(pane, text, 0, modal.moveSelectionCursor(text, range, t, pane.select), false);
        pane.sticky_col = @intCast(goal);
    }

    pub fn visualMove(
        pane: *Pane,
        text: []const u8,
        range: modal.Selection,
        down: bool,
        cnt: usize,
        width: usize,
    ) void {
        const cur = modal.selectionCursor(text, range);
        const pos = File.textPosition(pane, text, cur);
        const last_row = File.textLineCount(pane, text) - 1;
        var row = pos.row;
        var line = modal.lineSlice(text, row);
        var vrow = File.visualRow(line, pos.col, width);
        const goal: usize = if (pane.sticky_col >= 0)
            @intCast(pane.sticky_col)
        else
            File.rawDisplayCol(line[vrow.start..vrow.end], pos.col -| vrow.start);
        var steps = @max(1, cnt);
        while (steps > 0) : (steps -= 1) {
            if (down) {
                if (vrow.end < line.len) {
                    vrow = File.visualRow(line, vrow.end, width);
                    continue;
                }
                if (row == last_row) break;
                row += 1;
                line = modal.lineSlice(text, row);
                vrow = File.visualRow(line, 0, width);
            } else {
                if (vrow.start > 0) {
                    vrow = File.visualRow(line, vrow.start - 1, width);
                    continue;
                }
                if (row == 0) break;
                row -= 1;
                line = modal.lineSlice(text, row);
                vrow = File.visualRow(line, line.len, width);
            }
        }
        // The newline slot is a real cursor position, but the first byte of the
        // NEXT visual row is not: landing there would read as two rows moved.
        var target_col = vrow.start + File.rawAtDisplay(line[vrow.start..vrow.end], goal);
        if (vrow.end < line.len and target_col >= vrow.end)
            target_col = modal.graphemeStart(line, vrow.end - 1);
        const t = File.textOffset(pane, text, .{ .row = row, .col = target_col });
        // extend mode never walks onto the empty trailing line (helix)
        if (pane.select and t == text.len and text.len > 0 and text[text.len - 1] == '\n') return;
        setRange(pane, text, 0, modal.moveSelectionCursor(text, range, t, pane.select), false);
        pane.sticky_col = @intCast(goal);
    }

    /// Ctrl-d/u: scroll half a page AND move the cursor by the same rows
    pub fn halfPageMove(pane: *Pane, text: []const u8, range: modal.Selection, down: bool) void {
        const half: i32 = @max(1, @divTrunc(@as(i32, pane.rows), 2));
        pane.scrollBy(if (down) half else -half);
        verticalMove(pane, text, range, down, @intCast(half));
    }

    /// helix `scroll` without cursor sync (Ctrl-f/b, PgUp/PgDn, zj/zk): shift
    /// the view, then snap a fallen-out cursor to the near scrolloff edge, col 0
    pub fn scrollViewMove(pane: *Pane, text: []const u8, range: modal.Selection, delta: i32) void {
        const margin: i32 = @min(config.scroll_off, @divTrunc(@as(i32, pane.rows) - 1, 2));
        pane.scrollBy(delta);
        const top = pane.scroll();
        const last_row: i32 = @intCast(File.textLineCount(pane, text) - 1);
        const cur = modal.selectionCursor(text, range);
        if (delta > 0) {
            const snap: i32 = @max(0, @min(top + margin, last_row));
            const head = File.textLineStart(pane, text, @intCast(snap));
            if (head <= cur) return;
            const anchor = if (pane.select) range.anchor else head;
            setRange(pane, text, 0, .{ .anchor = anchor, .head = head }, false);
        } else {
            const snap: i32 = @max(0, @min(top + @as(i32, pane.rows) - margin - 1, last_row));
            const head = File.textLineStart(pane, text, @intCast(snap));
            if (head >= cur) return;
            const anchor = if (pane.select) range.anchor else head;
            setRange(pane, text, 0, .{ .anchor = anchor, .head = head }, false);
        }
    }

    /// gt/gc/gb: view-relative rows, col 0, scrolloff clamped (helix goto_window)
    pub fn gotoWindow(pane: *Pane, text: []const u8, range: modal.Selection, which: enum { top, center, bottom }, cnt: usize) void {
        const margin: i32 = @min(config.scroll_off, @divTrunc(@as(i32, pane.rows) - 1, 2));
        const top = pane.scroll();
        const last_row: i32 = @intCast(File.textLineCount(pane, text) - 1);
        const last_vis: i32 = @min(@as(i32, pane.rows) - 1, last_row - top);
        const n: i32 = @intCast(cnt - 1);
        var vline: i32 = switch (which) {
            .top => top + margin + n,
            .center => top + @divTrunc(last_vis, 2),
            .bottom => top + last_vis - (margin + n),
        };
        vline = @max(vline, top + margin);
        vline = @min(vline, top + last_vis - margin);
        const row: i32 = std.math.clamp(vline, 0, last_row);
        pointMove(pane, text, range, File.textLineStart(pane, text, @intCast(row)));
    }

    /// helix Range::line_range — the inclusive line span a range covers
    pub fn rangeLineSpan(text: []const u8, r: modal.Selection) struct { start: usize, end: usize } {
        const from = @min(r.anchor, r.head);
        const to = @max(r.anchor, r.head);
        const to_adj = if (from == to) to else @max(modal.prevGrapheme(text, to), from);
        return .{ .start = modal.lineAtOffset(text, from), .end = modal.lineAtOffset(text, to_adj) };
    }

    fn lineStartOrEof(text: []const u8, line: usize) usize {
        if (line >= modal.cursorLineCount(text)) return text.len;
        return modal.lineStartOffset(text, line);
    }

    /// helix `x` extend_line_below: full lines incl. the newline, cursor ON
    /// the last one's '\n'; an already-line-bounded selection grows downward
    pub fn lineSelect(pane: *Pane, text: []const u8, range: modal.Selection, cnt: usize) void {
        const span = rangeLineSpan(text, range);
        const start = modal.lineStartOffset(text, span.start);
        const end = lineStartOrEof(text, span.end + 1);
        const full = @min(range.anchor, range.head) == start and @max(range.anchor, range.head) == end;
        const head = lineStartOrEof(text, span.end + cnt + @intFromBool(full));
        setRange(pane, text, 0, .{ .anchor = start, .head = head }, true);
    }

    /// helix `X` extend_to_line_bounds (direction kept)
    pub fn lineBoundsSelect(pane: *Pane, text: []const u8, range: modal.Selection) void {
        const span = rangeLineSpan(text, range);
        const start = modal.lineStartOffset(text, span.start);
        const end = lineStartOrEof(text, span.end + 1);
        const r: modal.Selection = if (range.head < range.anchor)
            .{ .anchor = end, .head = start }
        else
            .{ .anchor = start, .head = end };
        setRange(pane, text, 0, r, true);
    }

    /// helix `Alt-x` shrink_to_line_bounds (single-line selections untouched)
    pub fn shrinkSelToLineBounds(pane: *Pane, text: []const u8, range: modal.Selection) void {
        const span = rangeLineSpan(text, range);
        if (span.start == span.end) return;
        const from = @min(range.anchor, range.head);
        const to = @max(range.anchor, range.head);
        var start = modal.lineStartOffset(text, span.start);
        var end = lineStartOrEof(text, span.end + 1);
        if (start != from) start = lineStartOrEof(text, span.start + 1);
        if (end != to) end = modal.lineStartOffset(text, span.end);
        const expl = (pane.vsel.active and pane.vsel.explicit) or pane.msel.active;
        const r: modal.Selection = if (range.head < range.anchor)
            .{ .anchor = end, .head = start }
        else
            .{ .anchor = start, .head = end };
        setRange(pane, text, 0, r, expl);
    }

    /// pull the cursor back inside `text` after a rewrite; `row0` is the
    /// absolute surface row of its first line (0 for a file)
    pub fn clampCursor(pane: *Pane, text: []const u8, row0: i32) void {
        const n = modal.lineCount(text);
        const row: usize = @min(@as(usize, @intCast(@max(0, pane.cur_row - row0))), if (n == 0) 0 else n - 1);
        const llen = modal.lineSlice(text, row).len;
        pane.cur_row = @as(i32, @intCast(row)) + row0;
        pane.cur_col = @intCast(@min(@as(usize, @intCast(@max(0, pane.cur_col))), llen));
        pane.cur_pinned = true;
        pane.vsel.active = false;
        pane.msel.active = false;
        pane.ensureCursorVisible();
    }
};

pub const File = @import("File.zig");

pub const Output = @import("Output.zig");

pub const Mini = @import("Mini.zig");

pub const Image = @import("image.zig");

pub const Pdf = @import("pdf_view.zig");

pub const Terminal = @import("Terminal.zig");

test {
    _ = Pane;
    _ = File;
    _ = Output;
    _ = Mini;
    _ = Image;
    _ = Pdf;
    _ = Terminal;
}