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teksilo_core/
accessibility.rs

1// SPDX-License-Identifier: MPL-2.0
2// SPDX-FileCopyrightText: 2026 FernTech
3
4use accesskit::{Action, Live, Node, NodeId, Role, TextDirection, TextPosition, TextSelection};
5
6use crate::widget_id::WidgetId;
7
8pub(crate) mod adapter_ids;
9pub(crate) mod announcements;
10pub mod audit;
11pub mod target_audit;
12pub mod text_runs;
13
14/// Builder wrapper around accesskit::Node for widget accessibility declarations.
15pub struct AccessNodeBuilder {
16    inner: Node,
17    name: Option<String>,
18    value: Option<String>,
19    role: Role,
20    actions: Vec<Action>,
21    toggled: Option<bool>,
22    expanded: Option<bool>,
23    selected: Option<bool>,
24    hidden: bool,
25    /// The owning widget's id. Set at construction time by the
26    /// tree walker (via `AccessNodeBuilder::for_widget`). Used by
27    /// the sub-tree API (`push_paragraph_child` / `push_text_run_child`)
28    /// to derive synthetic NodeIds without asking the caller to
29    /// pass the WidgetId at every call site.
30    owner: Option<WidgetId>,
31    /// Pending text selection targeting the widget's own node id.
32    /// Resolved at `build(id)` time because the widget doesn't know
33    /// its node id during `accessibility(&self, builder)`.
34    pending_self_selection: Option<(usize, usize)>,
35    /// Deferred text selection targeting synthetic child NodeIds
36    /// (TextRuns). Unlike `pending_self_selection`, these
37    /// TextPositions reference NodeIds that are already known at
38    /// the time the widget calls `set_text_selection_to`, so we
39    /// can populate the selection during `build(id)` directly —
40    /// the field just holds them until that point.
41    pending_explicit_selection: Option<(TextPosition, TextPosition)>,
42    /// Synthetic child nodes emitted by the widget via
43    /// `push_paragraph_child` / `push_text_run_child`. Drained by
44    /// the tree walker after `Widget::accessibility(&self, builder)`
45    /// returns and merged into the full AccessKit `TreeUpdate`.
46    children_collected: Vec<(NodeId, Node)>,
47    /// Bounds a widget declared for its synthetic children in **its own**
48    /// coordinate space, translated into window space by [`build`] —
49    /// which is the first moment the owner's absolute rect is known,
50    /// because the walker writes it onto the node just before calling.
51    ///
52    /// A widget that already holds absolute rects (a scene item, a
53    /// composite emitting geometry it got from a child it placed) calls
54    /// `set_bounds` on the child node directly and never appears here.
55    ///
56    /// [`build`]: AccessNodeBuilder::build
57    child_local_bounds: Vec<(NodeId, teksilo_canvas::Rect)>,
58    /// This builder exists only to harvest an accessible *name* — the
59    /// merge pass and the tooltip-description probe both run a widget's
60    /// `accessibility()` on a throwaway builder and read nothing but the
61    /// name off it. Emitting synthetic children there would allocate
62    /// node ids that never reach the tree, and, worse, would be
63    /// discarded along with the builder while the widget's real node
64    /// keeps its own copies.
65    name_probe: bool,
66}
67
68/// The ids of every `Role::TextRun` this node attached to **itself**, or
69/// `None` when there are none.
70///
71/// Scoped to the node's own child list on purpose. A builder's collected
72/// vector also holds *grandchildren* — a scene item is emitted through a
73/// nested builder whose whole subtree is folded into the outer one — and
74/// those belong to a parent of their own, which may well be a
75/// `Role::Label` that does support ranges. Dropping them because the
76/// *outer* node cannot carry runs would delete nodes the item's own
77/// children list still names, and `accesskit_consumer` panics on a
78/// child id that reaches no node.
79fn own_run_ids(
80    inner: &Node,
81    children: &[(NodeId, Node)],
82) -> Option<std::collections::HashSet<NodeId>> {
83    let attached: std::collections::HashSet<NodeId> = inner.children().iter().copied().collect();
84    let ids: std::collections::HashSet<NodeId> = children
85        .iter()
86        .filter(|(id, node)| node.role() == Role::TextRun && attached.contains(id))
87        .map(|(id, _)| *id)
88        .collect();
89    (!ids.is_empty()).then_some(ids)
90}
91
92/// Everything one `Role::TextRun` node needs.
93#[derive(Debug, Clone)]
94pub struct TextRunSpec {
95    /// Mixed with the owner and the run kind to derive the node id.
96    pub element_id: u64,
97    pub value: String,
98    /// UTF-8 byte length of each character of `value`. Their sum must be
99    /// `value.len()`; AccessKit panics otherwise.
100    pub character_lengths: Vec<u8>,
101    pub word_starts: Vec<u8>,
102    pub character_positions: Vec<f32>,
103    pub character_widths: Vec<f32>,
104    pub bounds: teksilo_canvas::Rect,
105    /// `true` when `bounds` is already in window space.
106    pub bounds_are_absolute: bool,
107    pub text_direction: TextDirection,
108    pub attrs: TextRunAttributes,
109}
110
111/// A Teksilo affine as AccessKit expresses one.
112///
113/// Both store a 3×2 matrix mapping `(x, y)` to
114/// `(a·x + c·y + tx, b·x + d·y + ty)`, and both spell it `[a, b, c, d, tx, ty]`,
115/// so this is a widening cast and not a change of convention.
116///
117/// Write the result with [`accesskit::Node::set_transform`] on a node whose
118/// own bounds — and every rectangle below it — are stated in a coordinate
119/// space of its own rather than in window space. That is the one supported way
120/// to publish such a rectangle: a consumer reads `bounds` "in the coordinate
121/// space of the nearest ancestor with a non-`None` transform", composes the
122/// chain for `bounding_box()`, and inverts it per step when hit-testing, so
123/// projecting by hand instead would be exact only for the rectangle and wrong
124/// for the per-character geometry and the hit path.
125///
126/// The framework does this for the children of a content-transform node (see
127/// `WidgetTree::build_accessibility_recursive`); a widget emitting synthetic
128/// children of its own in a non-window space — a scene item, a chart mark —
129/// calls it directly.
130pub fn to_accesskit_affine(t: teksilo_canvas::Transform2D) -> accesskit::Affine {
131    let [a, b, c, d, tx, ty] = t.m;
132    accesskit::Affine::new([a as f64, b as f64, c as f64, d as f64, tx as f64, ty as f64])
133}
134
135/// The text a node announces as its name, read the way every platform adapter
136/// reads it.
137///
138/// A `Role::Label` carries its text in `value`, not `label` — Windows UIA
139/// derives the Name from `value` for that role, macOS exposes it as
140/// `AXValue`, and `accesskit_consumer` reads `value` when another control is
141/// `labelled_by` it. `AccessNodeBuilder::build` moves it there. Everything
142/// else carries its name in `label`. A test or probe that reads one property
143/// sees nothing on half the tree.
144///
145/// Neither falls back to the other. The AT-SPI, UIA and macOS adapters all
146/// take the name from `label_comes_from_value() ? value : label`
147/// (`accesskit_atspi_common` `node.rs:38-44`, `accesskit_windows`
148/// `node.rs:404-413`, `accesskit_macos` `node.rs:328-334`, with
149/// `label_comes_from_value` true for `Role::Label` alone, consumer
150/// `node.rs:744-746`), so a `Status` that holds its text only as a value has
151/// no name, and no platform announces it as one. This reads one node's own
152/// properties: a name that comes through `labelled_by` takes the consumer's
153/// `NodeRef::label` to follow.
154pub fn announced_text(node: &Node) -> Option<&str> {
155    if node.role() == Role::Label {
156        node.value()
157    } else {
158        node.label()
159    }
160}
161
162/// Whether a node with this role can carry text ranges at all.
163///
164/// `accesskit_consumer::Node::supports_text_ranges` is
165/// `(is_text_input || role ∈ {Label, Document, Terminal}) && has runs`
166/// (`accesskit_consumer-0.39.0/src/text.rs:1402`). Runs under any other
167/// role are inert: no platform exposes them, and they still cost a node
168/// in every update.
169pub fn role_supports_text_ranges(role: Role) -> bool {
170    matches!(
171        role,
172        Role::Label
173            | Role::Document
174            | Role::Terminal
175            | Role::TextInput
176            | Role::MultilineTextInput
177            | Role::SearchInput
178            | Role::DateInput
179            | Role::DateTimeInput
180            | Role::WeekInput
181            | Role::MonthInput
182            | Role::TimeInput
183            | Role::EmailInput
184            | Role::NumberInput
185            | Role::PasswordInput
186            | Role::PhoneNumberInput
187            | Role::UrlInput
188            | Role::EditableComboBox
189            | Role::SpinButton
190    )
191}
192
193/// Discriminator kind for synthetic-NodeId hashing. Different
194/// kinds sharing the same (widget_id, element_id) tuple produce
195/// distinct NodeIds so paragraph and run nodes for the same
196/// source element don't collide.
197#[derive(Debug, Clone, Copy)]
198#[repr(u8)]
199pub enum SyntheticKind {
200    Paragraph = 1,
201    TextRun = 2,
202    ImageRun = 3,
203    /// An inline link span inside a label-style widget's text
204    /// (e.g. `[docs](url)` inside a TextWidget with `.markup(true)`
205    /// enabled). Each link span becomes one synthetic child of the
206    /// hosting widget's own node, with `Role::Link` and the link label
207    /// as its name.
208    Link = 4,
209    /// A lightweight `SceneItem` rendered by `teksilo_scene::SceneView`.
210    /// Items live outside the arena — `SceneView::accessibility`
211    /// emits one synthetic child per visible item using
212    /// `push_scene_child`.
213    SceneItem = 5,
214    /// A logical grouping declared via `Scene::add_a11y_group`.
215    /// Pure AT structure — no visual counterpart. The parent's
216    /// children list orders mixed `SceneItem` and `SceneGroup`
217    /// synthetic NodeIds however the app declared the logical tree.
218    SceneGroup = 6,
219    /// A magnetism anchor ("magnet") attached to a scene item. Emitted
220    /// as a synthetic child of the owning item's node by
221    /// `SceneView::accessibility` when magnetism is enabled, so the
222    /// anchor is screen-reader perceivable and can be the target of the
223    /// view's `active_descendant` during the keyboard connect flow.
224    SceneMagnet = 7,
225    /// A per-datum mark (bar / line point / pie slice) emitted by a
226    /// `teksilo-charts` widget's `accessibility()`.
227    ChartMark = 8,
228    /// An annotation body (a comment thread) attached to a run of text, emitted
229    /// by a rich-text widget alongside the `TextRun` that carries it. The run
230    /// points at this node through the `details` relation — AccessKit's
231    /// `aria-details` — which is what lets a screen reader say "has comment" and
232    /// let the user navigate in, rather than reciting the thread inline every
233    /// time the caret crosses the span.
234    Annotation = 9,
235    /// A positional mark in a margin lane — the strip beside a scroll area that
236    /// maps where things are in a document rather than picturing it.
237    ///
238    /// Emitted by the lane widget's `accessibility()`, one synthetic child per
239    /// mark, the same shape [`SyntheticKind::ChartMark`] uses per datum. Marks
240    /// get their own nodes, rather than riding the content they refer to, for
241    /// the reason `CodeGutter` gives for *not* doing so: line numbers are
242    /// uniform, dense and derivable from the text, so they belong on the
243    /// paragraph node as `position_in_set`; lane marks are sparse, heterogeneous
244    /// and not derivable from anything — "a comment from Marie at 62 percent" is
245    /// not in the paragraph, so there is no node to delegate to.
246    LaneMark = 10,
247    /// The selection transform frame and its handles, emitted by
248    /// `teksilo_scene::SceneView` when a transform controller is installed.
249    ///
250    /// One frame node per *view* plus at most nine handle nodes hang off it —
251    /// not one per item — because the frame belongs to the selection rather
252    /// than to any item, and a multi-item selection has no owner. The handles
253    /// are a paint pass, never scene items, so they add nothing to the item
254    /// walk, to `items_in_rect`, or to a marquee's result.
255    SceneHandle = 11,
256    /// A table inside a rich-text document, emitted by the rich-text
257    /// accessibility walk from a `FlowElementSnapshot::Table`. Keyed by the
258    /// document's own `table_id`, so the node survives every edit that does
259    /// not destroy the table.
260    RichTextTable = 12,
261    /// One row of a [`SyntheticKind::RichTextTable`], keyed by the table and
262    /// the row index together.
263    RichTextTableRow = 13,
264    /// One cell of a [`SyntheticKind::RichTextTable`], keyed by the table and
265    /// the cell's row and column together.
266    RichTextTableCell = 14,
267    /// The text container inside a [`SyntheticKind::RichTextTableCell`].
268    ///
269    /// A cell's text runs cannot hang off the cell directly. The platform
270    /// adapters route a changed run's text-change event to its *filtered*
271    /// parent, and `accesskit_consumer`'s `common_filter` makes only
272    /// `GenericContainer` and `TextRun` transparent — so a `Role::Cell`
273    /// parent is asked whether it `supports_text_ranges()`, answers no, and
274    /// every keystroke typed into the cell is dropped before it reaches a
275    /// screen reader. This node is the `Role::Label` between the two: it is
276    /// text-range capable, so the event survives, and it is what a reader
277    /// announces as the cell's content.
278    RichTextCellText = 15,
279    /// The text container inside a structural block-level node — a
280    /// `Role::Heading`, or a `Role::Blockquote`.
281    ///
282    /// Exactly the problem [`SyntheticKind::RichTextCellText`] solves, in the
283    /// other places a structural node sits between the editor and its runs:
284    /// neither role is text-range capable, so runs parented straight onto one
285    /// had every edit beneath it dropped before it reached a screen reader.
286    /// Keyed by the **block's** own id — one per block, so a heading inside a
287    /// blockquote still has exactly one — which is a different id space from a
288    /// cell's packed `(table, row, column)`, so the two kinds stay distinct
289    /// rather than relying on those spaces never colliding.
290    RichTextBlockText = 16,
291    /// A blockquote in a rich-text document, emitted from a
292    /// `FlowElementSnapshot::Frame` whose `FrameFormat::is_blockquote` is set.
293    ///
294    /// Only a blockquote earns a node. A frame is otherwise a layout box — a
295    /// positioned or floating text frame — with no role to announce, and
296    /// wrapping one in a node a reader stops on would be AT noise.
297    RichTextBlockquote = 17,
298    /// A node of a web page, mirrored from the accessibility tree an engine
299    /// that renders offscreen publishes (`teksilo-webview`'s Servo backend).
300    /// Keyed by the page's own node id, so a node keeps its id across the
301    /// engine's incremental updates.
302    WebPageNode = 18,
303}
304
305/// A live-region announcement every platform adapter would have made.
306///
307/// Teksilo has no OS accessibility layer in headless mode, and even with
308/// one there is no in-process way to observe what the platform *spoke*.
309/// So a tree that [records announcements](crate::WidgetTree::records_announcements)
310/// replays every update [`crate::WidgetTree::sync_accessibility`] returns
311/// through `accesskit_consumer`, the diff the AT-SPI, Windows and
312/// macOS adapters are all built on, and the announcements those adapters
313/// would raise are kept in a ring that an automation or test harness drains
314/// through [`crate::WidgetTree::announcements_since`]: a live node entering
315/// the filtered tree with a name, or a live node in it whose name changed.
316/// A live node the adapters cannot hear, because it is hidden, inside a
317/// hidden subtree, or carries its text as a `value` where its role takes a
318/// label, is not in the ring. This models what the adapters hand a screen
319/// reader, not what the screen reader then says, so it does not replace
320/// listening to one.
321#[derive(Debug, Clone, PartialEq, Eq)]
322pub struct Announcement {
323    /// Monotonic sequence number, starting at 1. `announcements_since(n)`
324    /// returns every announcement whose `seq > n`.
325    pub seq: u64,
326    /// The node's name as every adapter computes it, which is the string the
327    /// platform announces: the `value` of a `Role::Label`, the label of any
328    /// other role, followed through `labelled_by` when the node has none of
329    /// its own.
330    pub text: String,
331    /// `true` for `Live::Assertive`, `false` for `Live::Polite`. A node with
332    /// no setting of its own takes its nearest live ancestor's, as the
333    /// adapters do.
334    pub assertive: bool,
335}
336
337/// Top bit of the u64 NodeId encoding. Set for synthetic (widget-
338/// emitted child) NodeIds, clear for widget-derived NodeIds.
339/// Slotmap-derived WidgetIds never set bit 63 in practice because
340/// slotmap's KeyData encoding occupies bits 32-63 with a version
341/// counter that starts at 1.
342pub(crate) const SYNTHETIC_BIT: u64 = 1u64 << 63;
343
344/// Stable hash of (parent widget, element id, kind) producing a
345/// synthetic NodeId that survives edits for as long as the
346/// underlying element id is stable. Used by `AccessNodeBuilder`'s
347/// sub-tree API to allocate NodeIds for paragraph / text-run
348/// children without colliding with widget-derived NodeIds.
349pub fn synthetic_node_id(parent: WidgetId, element_id: u64, kind: SyntheticKind) -> NodeId {
350    use slotmap::Key;
351    let parent_raw = parent.data().as_ffi();
352    let h = fnv_mix_u64(parent_raw, element_id, kind as u64);
353    NodeId((h & !SYNTHETIC_BIT) | SYNTHETIC_BIT)
354}
355
356/// Convert an ARIA-style **1-based** ordinal to the **zero-based** integer
357/// AccessKit stores.
358///
359/// AccessKit deliberately departs from ARIA on four properties, and says so in
360/// its own documentation (`accesskit-0.25.0/src/lib.rs`, each carrying a
361/// "**Difference with ARIA**" paragraph):
362///
363/// | property | ARIA | AccessKit |
364/// |---|---|---|
365/// | `position_in_set` / `aria-posinset` | 1-based | **0-based** |
366/// | `row_index` / `aria-rowindex` | 1-based | **0-based** |
367/// | `column_index` / `aria-colindex` | 1-based | **0-based** |
368/// | `level` / `aria-level` | 1-based | **0-based** |
369///
370/// Two of the three platform adapters add the 1 back before handing the value
371/// to the platform — `accesskit_windows-0.35.0/src/node.rs:682-687` and
372/// `:698-701`, `accesskit_atspi_common-0.20.0/src/node.rs:394` — so writing an
373/// ARIA-shaped number straight through lands one too high in what the screen
374/// reader actually says. `accesskit_macos-0.27.0` reads none of the four, so
375/// the error is invisible there, which is part of why it went unnoticed.
376///
377/// Teksilo's public surface stays 1-based, because that is the convention every
378/// call site, every doc comment and ARIA itself already use, and because "the
379/// first tab is tab 1" is what the value means to a person. The conversion
380/// happens once, here, at the boundary.
381///
382/// Saturating rather than panicking on 0: an off-by-one in a caller should
383/// produce a slightly wrong announcement, not take down the application. A
384/// caller that passes 0 gets the same node it would have got for 1.
385fn to_accesskit_ordinal(one_based: usize) -> usize {
386    debug_assert!(
387        one_based >= 1,
388        "AccessKit ordinals are 1-based at this boundary; 0 is not a position, \
389         row, column or level"
390    );
391    one_based.saturating_sub(1)
392}
393
394/// Whether a given `NodeId` is a synthetic child node (emitted by a
395/// widget via `push_paragraph_child` / `push_text_run_child`) rather
396/// than a widget-derived NodeId.
397pub fn is_synthetic(id: NodeId) -> bool {
398    id.0 & SYNTHETIC_BIT != 0
399}
400
401/// FNV-1a-inspired 64-bit mixer for three u64 inputs. Not a
402/// cryptographic hash — just a fast, deterministic, well-distributed
403/// mix for collision-free synthetic NodeIds across the
404/// (widget, element, kind) space.
405pub(crate) fn fnv_mix_u64(a: u64, b: u64, c: u64) -> u64 {
406    const FNV_OFFSET: u64 = 0xcbf29ce484222325;
407    const FNV_PRIME: u64 = 0x100000001b3;
408    let mut h = FNV_OFFSET;
409    for byte in a
410        .to_le_bytes()
411        .iter()
412        .chain(b.to_le_bytes().iter())
413        .chain(c.to_le_bytes().iter())
414    {
415        h ^= *byte as u64;
416        h = h.wrapping_mul(FNV_PRIME);
417    }
418    h
419}
420
421/// Styling attributes surfaced to assistive technology on a synthetic
422/// `Role::TextRun` node (WCAG 1.3.1 Info and Relationships / EN 301 549
423/// 11.5.2.9 "text attributes"). All fields default to "unset"; a rich-text
424/// widget populates them per formatting run so a screen reader can convey
425/// bold / italic / underline / strikethrough spans. AccessKit has no
426/// dedicated `bold` property, so [`bold`](Self::bold) folds into
427/// `set_font_weight(700)` when no explicit [`font_weight`](Self::font_weight)
428/// is given.
429#[derive(Debug, Clone, Copy, Default)]
430pub struct TextRunAttributes {
431    /// Explicit numeric font weight (`100..=900`). Takes precedence over
432    /// [`bold`](Self::bold).
433    pub font_weight: Option<u16>,
434    /// Bold flag; folded to weight `700` when `font_weight` is `None`.
435    pub bold: bool,
436    pub italic: bool,
437    pub underline: bool,
438    pub strikethrough: bool,
439}
440
441/// Apply a run's formatting to its node.
442///
443/// WCAG 1.3.1 / EN 301 549 11.5.2.9. AccessKit has no bold flag, so an
444/// explicit weight wins and a bare `bold` folds to 700.
445fn apply_run_attrs(node: &mut Node, attrs: TextRunAttributes) {
446    if let Some(weight) = attrs.font_weight {
447        node.set_font_weight(weight as f32);
448    } else if attrs.bold {
449        node.set_font_weight(700.0);
450    }
451    if attrs.italic {
452        node.set_italic();
453    }
454    if attrs.underline {
455        node.set_underline(default_text_decoration());
456    }
457    if attrs.strikethrough {
458        node.set_strikethrough(default_text_decoration());
459    }
460}
461
462/// The `TextDecoration` used for underline / strikethrough on a text run.
463/// Screen readers key off the *presence* of a decoration, not its colour,
464/// so a solid neutral (black) decoration is sufficient; the run's own
465/// foreground colour is not plumbed through this synthetic-node path.
466fn default_text_decoration() -> accesskit::TextDecoration {
467    accesskit::TextDecoration {
468        style: accesskit::TextDecorationStyle::Solid,
469        color: accesskit::Color {
470            red: 0,
471            green: 0,
472            blue: 0,
473            alpha: 255,
474        },
475    }
476}
477
478impl AccessNodeBuilder {
479    pub fn new() -> Self {
480        Self {
481            inner: Node::new(Role::Unknown),
482            name: None,
483            value: None,
484            role: Role::Unknown,
485            actions: Vec::new(),
486            toggled: None,
487            expanded: None,
488            selected: None,
489            hidden: false,
490            owner: None,
491            pending_self_selection: None,
492            pending_explicit_selection: None,
493            children_collected: Vec::new(),
494            child_local_bounds: Vec::new(),
495            name_probe: false,
496        }
497    }
498
499    /// Construct a builder with a known owner WidgetId. Used by the
500    /// tree walker when invoking `Widget::accessibility`; the owner
501    /// id drives synthetic NodeId derivation in the sub-tree API.
502    pub fn for_widget(owner: WidgetId) -> Self {
503        let mut b = Self::new();
504        b.owner = Some(owner);
505        b
506    }
507
508    /// A builder whose only purpose is to harvest a widget's accessible
509    /// *name*.
510    ///
511    /// The merge pass (`AccessSubtreeMode::Merge`) and the
512    /// tooltip-description probe both run a widget's `accessibility()`
513    /// against a throwaway builder and read nothing off it but the name.
514    /// Text runs must not be emitted there: their node ids would never
515    /// reach the tree, and the run-emitting helpers still need to compute
516    /// the merged text so the *name* comes out right.
517    pub fn for_name_probe(owner: WidgetId) -> Self {
518        let mut b = Self::for_widget(owner);
519        b.name_probe = true;
520        b
521    }
522
523    /// Whether this builder is a name probe (see
524    /// [`for_name_probe`](Self::for_name_probe)), or has no owner at all —
525    /// the two cases in which a widget must emit no synthetic children.
526    ///
527    /// An owner-less builder is a legitimate, if unusual, caller: the
528    /// overlay measurement path and the debug inspector both run
529    /// `accessibility()` on an arbitrary widget through
530    /// [`AccessNodeBuilder::new`] to read its role and name.
531    pub fn emits_no_children(&self) -> bool {
532        self.name_probe || self.owner.is_none()
533    }
534
535    pub fn set_role(&mut self, role: Role) {
536        self.role = role;
537        self.inner.set_role(role);
538    }
539
540    pub fn set_name(&mut self, name: impl Into<String>) {
541        let name: String = name.into();
542        self.inner.set_label(name.clone());
543        self.name = Some(name);
544    }
545
546    pub fn set_disabled(&mut self) {
547        self.inner.set_disabled();
548    }
549
550    /// Clear the disabled flag set by an earlier `set_disabled()` call. Used
551    /// by the override layer to un-set state a widget emitted unconditionally
552    /// (e.g. a Panel that always calls `set_hidden`/`set_disabled`).
553    pub fn clear_disabled(&mut self) {
554        self.inner.clear_disabled();
555    }
556
557    pub fn add_action(&mut self, action: Action) {
558        self.inner.add_action(action);
559        self.actions.push(action);
560    }
561
562    /// Remove a previously-advertised action. Used by the override layer
563    /// (`access_remove_action`) to suppress an action a widget emitted but
564    /// that doesn't apply in this composition.
565    pub fn remove_action(&mut self, action: Action) {
566        self.inner.remove_action(action);
567        self.actions.retain(|a| *a != action);
568    }
569
570    pub fn set_value(&mut self, value: impl Into<String>) {
571        let v: String = value.into();
572        self.inner.set_value(v.clone());
573        self.value = Some(v);
574    }
575
576    /// Advertise a color value on this node — typically paired with
577    /// [`accesskit::Role::ColorWell`]. Takes a `teksilo_tokens::Color` (f32
578    /// channels) and quantizes to AccessKit's 8-bit `Color` representation.
579    pub fn set_color_value(&mut self, color: teksilo_tokens::Color) {
580        let ak = accesskit::Color {
581            red: (color.r() * 255.0).round().clamp(0.0, 255.0) as u8,
582            green: (color.g() * 255.0).round().clamp(0.0, 255.0) as u8,
583            blue: (color.b() * 255.0).round().clamp(0.0, 255.0) as u8,
584            alpha: (color.a() * 255.0).round().clamp(0.0, 255.0) as u8,
585        };
586        self.inner.set_color_value(ak);
587    }
588
589    pub fn set_description(&mut self, description: impl Into<String>) {
590        self.inner.set_description(description.into());
591    }
592
593    pub fn set_live(&mut self, live: Live) {
594        self.inner.set_live(live);
595    }
596
597    pub fn set_described_by(&mut self, ids: impl Into<Vec<NodeId>>) {
598        self.inner.set_described_by(ids);
599    }
600
601    /// Append one node to the `described_by` relationship list. Mirror of
602    /// the existing `push_controlled`; used by the override layer's
603    /// `access_described_by` builder method and by the framework's
604    /// tooltip wiring. The relation by itself reaches no screen reader
605    /// through AccessKit 0.25; the tree writes each target's text into the
606    /// node's description when it builds the update.
607    pub fn push_described_by(&mut self, id: NodeId) {
608        self.inner.push_described_by(id);
609    }
610
611    /// Append one node to the `labelled_by` relationship list. Used by
612    /// `access_labelled_by` to point at an external label widget.
613    pub fn push_labelled_by(&mut self, id: NodeId) {
614        self.inner.push_labelled_by(id);
615    }
616
617    /// Replace the `details` relationship list — AccessKit's analogue of
618    /// `aria-details`.
619    ///
620    /// Distinct from `described_by`, and deliberately so: a *description* is text
621    /// a screen reader appends when announcing the element, while *details* points
622    /// at a structured node the user can navigate **into**. The W3C annotations
623    /// pattern is built on that difference — an annotated run carries
624    /// `aria-details` to a `role="comment"` node, so the reader can say "has
625    /// comment" and let the user go read it, rather than reciting a whole thread
626    /// inline every time the caret crosses the span.
627    pub fn set_details(&mut self, ids: impl Into<Vec<NodeId>>) {
628        self.inner.set_details(ids);
629    }
630
631    /// Append one node to the `details` relationship list.
632    ///
633    /// It is a list, not a single id, because overlapping annotations are normal:
634    /// one run of text can carry several comments, and each gets its own entry.
635    pub fn push_detail(&mut self, id: NodeId) {
636        self.inner.push_detail(id);
637    }
638
639    /// Stable author-supplied identifier (test/debug id, equivalent to
640    /// `aria-label`-style `data-testid`). Maps to `accesskit::Node::set_author_id`.
641    pub fn set_author_id(&mut self, id: impl Into<String>) {
642        self.inner.set_author_id(id.into());
643    }
644
645    /// Replace the node's custom-action list with `actions`, and keep the
646    /// supported-action gate in step with it.
647    ///
648    /// **The gate is the whole reachability story, not the list.** A platform
649    /// adapter reports a node's custom actions through
650    /// [`accesskit::Action::CustomAction`] being
651    /// supported, not through the list being non-empty
652    /// (`accesskit_ios-0.2.0/src/node.rs:109` is the one that says so in code),
653    /// so a list published without it is decoration: named, announced by
654    /// nothing, invokable by nobody. Three separate widgets in this repo have
655    /// shipped that exact defect, each having to remember a second call beside
656    /// this one.
657    ///
658    /// So this method owns both halves. A non-empty list advertises the gate; an
659    /// empty one withdraws it, because a gate with nothing behind it offers an
660    /// assistive-technology user a menu that is not there. Callers that also
661    /// call `add_action(Action::CustomAction)` themselves are correct and
662    /// unaffected — both operations are idempotent.
663    pub fn set_custom_actions(&mut self, actions: Vec<accesskit::CustomAction>) {
664        let empty = actions.is_empty();
665        self.inner.set_custom_actions(actions);
666        if empty {
667            self.remove_action(accesskit::Action::CustomAction);
668        } else {
669            self.add_action(accesskit::Action::CustomAction);
670        }
671    }
672
673    pub fn set_toggled(&mut self, toggled: bool) {
674        self.toggled = Some(toggled);
675        self.inner.set_toggled(if toggled {
676            accesskit::Toggled::True
677        } else {
678            accesskit::Toggled::False
679        });
680    }
681
682    pub fn set_expanded(&mut self, expanded: bool) {
683        self.expanded = Some(expanded);
684        self.inner.set_expanded(expanded);
685    }
686
687    pub fn set_has_popup(&mut self, kind: accesskit::HasPopup) {
688        self.inner.set_has_popup(kind);
689    }
690
691    /// Placeholder text displayed when the widget has no user-entered value
692    /// yet. Screen readers treat this distinctly from `value` — they'll
693    /// announce the placeholder as hint text rather than as the current
694    /// value. Used by `ComboBox` when selection is `None`, by `TextInput`
695    /// before the user types, etc.
696    pub fn set_placeholder(&mut self, placeholder: impl Into<String>) {
697        self.inner.set_placeholder(placeholder.into());
698    }
699
700    /// Target URL for link-like widgets. Maps to `aria-url` / platform
701    /// link metadata so screen readers can announce the destination
702    /// (e.g. "link, `https://example.com`"). Informational only — does
703    /// not navigate when activated.
704    pub fn set_url(&mut self, url: impl Into<String>) {
705        self.inner.set_url(url.into());
706    }
707
708    /// Keyboard shortcut announcement (e.g. `"Ctrl+S"`). Maps to
709    /// `aria-keyshortcuts`. Used by menu items and buttons whose
710    /// chord is shown visually but must also be exposed to assistive
711    /// tech so shortcut users discover it.
712    pub fn set_keyboard_shortcut(&mut self, shortcut: impl Into<String>) {
713        self.inner.set_keyboard_shortcut(shortcut.into());
714    }
715
716    /// Autocomplete behavior for combobox / text input widgets. Maps to
717    /// ARIA `aria-autocomplete`: `Inline` completes within the field,
718    /// `List` shows a popup of matching values, `Both` does both.
719    pub fn set_auto_complete(&mut self, kind: accesskit::AutoComplete) {
720        self.inner.set_auto_complete(kind);
721    }
722
723    /// Selection state — used by `RadioButton`, `Tab`, `ListBoxOption`,
724    /// `TreeItem`, menu items in radio/check groups, etc. This is the
725    /// correct property for "this option in a mutually exclusive
726    /// group is the active one"; don't confuse with `set_toggled`,
727    /// which models checkbox/switch on-off state.
728    pub fn set_selected(&mut self, selected: bool) {
729        self.selected = Some(selected);
730        self.inner.set_selected(selected);
731    }
732
733    pub fn set_orientation(&mut self, orientation: accesskit::Orientation) {
734        self.inner.set_orientation(orientation);
735    }
736
737    /// **1-based** index of this item in its parent set — the ARIA
738    /// `aria-posinset` convention, so the first item is 1.
739    ///
740    /// Use on `Role::Tab`, `Role::ListBoxOption`, `Role::Row`,
741    /// `Role::MenuItem` and similar collection items, and set
742    /// [`set_size_of_set`](Self::set_size_of_set) on their **container** so
743    /// assistive technology can announce "tab 3 of 5".
744    ///
745    /// ⚠ AccessKit's own `position_in_set` is **zero-based**, unlike
746    /// `aria-posinset` — see `accesskit-0.25.0/src/lib.rs`, "Difference with
747    /// ARIA". This wrapper converts, so callers keep the ARIA convention that
748    /// every caller and every doc in this repository already assumed. Do not
749    /// reach past it with `inner_mut().set_position_in_set(..)`: that skips the
750    /// conversion, and the value then arrives one too high on Windows and
751    /// Linux, both of which add the 1 back
752    /// (`accesskit_windows-0.35.0/src/node.rs:682-687`,
753    /// `accesskit_atspi_common-0.20.0/src/node.rs:394`).
754    pub fn set_position_in_set(&mut self, position: usize) {
755        self.inner
756            .set_position_in_set(to_accesskit_ordinal(position));
757    }
758
759    /// Total number of items in a collection — maps to ARIA `aria-setsize`.
760    ///
761    /// ⚠ Set this on the **container** (`Role::ListBox`, `Role::TabList`,
762    /// `Role::Tree`, `Role::Menu`, …), not on each item. Unlike
763    /// `aria-setsize`, which is per item, AccessKit resolves an item's set size
764    /// by walking *up* from its parent: `size_of_set_from_container`
765    /// (`accesskit_consumer-0.39.0/src/node.rs:629-641`) starts at
766    /// `filtered_parent`, so a value written on the item itself is read by no
767    /// adapter on any platform.
768    ///
769    /// Report the **logical** set size, not the realized virtualization window:
770    /// 200 for a 200-row list even when 20 rows exist as widgets.
771    pub fn set_size_of_set(&mut self, size: usize) {
772        self.inner.set_size_of_set(size);
773    }
774
775    /// **1-based** hierarchical depth — the ARIA `aria-level` convention, so a
776    /// root tree item is level 1 and an `<h1>` is level 1.
777    ///
778    /// ⚠ AccessKit's `level` is **zero-based**, unlike `aria-level`. This
779    /// wrapper converts. Reaching past it with `inner_mut().set_level(..)`
780    /// makes every heading and every tree row announce one level too deep on
781    /// Windows, which adds the 1 back
782    /// (`accesskit_windows-0.35.0/src/node.rs:698-701`).
783    pub fn set_level(&mut self, level: usize) {
784        self.inner.set_level(to_accesskit_ordinal(level));
785    }
786
787    // ── Grid / table semantics (`aria-rowcount` / `aria-colindex` / …) ──
788    //
789    // Typed wrappers over the corresponding `accesskit::Node` setters so
790    // grid/table widgets don't have to drop to `inner_mut()`. On a
791    // `Role::Grid` / `Role::Table` container set the *logical* row/column
792    // counts (not the realized window); on each cell set its 1-based
793    // row/column index.
794
795    /// Total logical row count on a grid/table container (`aria-rowcount`).
796    pub fn set_row_count(&mut self, count: usize) {
797        self.inner.set_row_count(count);
798    }
799
800    /// Total logical column count on a grid/table container (`aria-colcount`).
801    pub fn set_column_count(&mut self, count: usize) {
802        self.inner.set_column_count(count);
803    }
804
805    /// **1-based** row index of a cell or row — the ARIA `aria-rowindex`
806    /// convention, so the header row is 1 and the first body row is 2.
807    ///
808    /// ⚠ AccessKit's `row_index` is **zero-based**, unlike `aria-rowindex`.
809    /// This wrapper converts; `inner_mut().set_row_index(..)` does not.
810    pub fn set_row_index(&mut self, index: usize) {
811        self.inner.set_row_index(to_accesskit_ordinal(index));
812    }
813
814    /// **1-based** column index of a cell — the ARIA `aria-colindex`
815    /// convention, so the leftmost column is 1.
816    ///
817    /// ⚠ AccessKit's `column_index` is **zero-based**, unlike `aria-colindex`.
818    /// This wrapper converts; `inner_mut().set_column_index(..)` does not.
819    pub fn set_column_index(&mut self, index: usize) {
820        self.inner.set_column_index(to_accesskit_ordinal(index));
821    }
822
823    /// Number of rows a cell spans (`aria-rowspan`).
824    pub fn set_row_span(&mut self, span: usize) {
825        self.inner.set_row_span(span);
826    }
827
828    /// Number of columns a cell spans (`aria-colspan`).
829    pub fn set_column_span(&mut self, span: usize) {
830        self.inner.set_column_span(span);
831    }
832
833    /// Whether the container allows multiple selected items
834    /// (`aria-multiselectable`). Set on the `Role::Grid` / `Role::ListBox`
835    /// container in multi-select mode.
836    pub fn set_multiselectable(&mut self, value: bool) {
837        if value {
838            self.inner.set_multiselectable();
839        } else {
840            self.inner.clear_multiselectable();
841        }
842    }
843
844    /// The currently-active descendant (`aria-activedescendant`) — the
845    /// roving-focus pattern where focus stays on a composite container and
846    /// this points at the focused child (e.g. the focused grid cell).
847    pub fn set_active_descendant(&mut self, id: NodeId) {
848        self.inner.set_active_descendant(id);
849    }
850
851    /// Flag the node as a modal dialog. Use on `Role::Dialog` /
852    /// `Role::AlertDialog` when input is blocked outside the dialog.
853    pub fn set_modal(&mut self) {
854        self.inner.set_modal();
855    }
856
857    /// Mark this node as the current item within its container
858    /// (e.g. the "current page" crumb inside a `Navigation`, the
859    /// current step in a wizard). Maps to ARIA `aria-current`.
860    pub fn set_aria_current(&mut self, current: accesskit::AriaCurrent) {
861        self.inner.set_aria_current(current);
862    }
863
864    /// Single-step delta for `Slider` / `SpinButton` — how much the
865    /// value changes per keyboard arrow or Action::Increment tick.
866    pub fn set_numeric_value_step(&mut self, step: f64) {
867        self.inner.set_numeric_value_step(step);
868    }
869
870    /// Page-step delta for `Slider` / `SpinButton` — how much the
871    /// value changes per PgUp/PgDown or coarse adjustment.
872    pub fn set_numeric_value_jump(&mut self, jump: f64) {
873        self.inner.set_numeric_value_jump(jump);
874    }
875
876    /// Append a controlled-node relationship — e.g. a `Tab` pointing
877    /// at its matching `TabPanel`, a `ComboBox` pointing at its
878    /// listbox popup. AccessKit / ARIA equivalent of `aria-controls`.
879    pub fn push_controlled(&mut self, id: NodeId) {
880        self.inner.push_controlled(id);
881    }
882
883    /// Declare this radio button's membership in a radio group.
884    /// Each `RadioButton` node should push every sibling in its
885    /// group (including itself); screen readers use this to
886    /// announce positional info like "2 of 3".
887    pub fn push_to_radio_group(&mut self, id: NodeId) {
888        self.inner.push_to_radio_group(id);
889    }
890
891    pub fn set_numeric_value(&mut self, value: f64) {
892        self.inner.set_numeric_value(value);
893    }
894
895    pub fn set_min_numeric_value(&mut self, value: f64) {
896        self.inner.set_min_numeric_value(value);
897    }
898
899    pub fn set_max_numeric_value(&mut self, value: f64) {
900        self.inner.set_max_numeric_value(value);
901    }
902
903    /// Hide this node **and everything under it** from all assistive
904    /// technologies (equivalent to `aria-hidden="true"`). The node is still
905    /// in the widget tree but is invisible to screen readers and other ATs.
906    /// Use for purely decorative elements, e.g. scrollbars (AT scrolls via
907    /// the parent `ScrollView`'s scroll actions instead).
908    ///
909    /// The flag covers the subtree. `accesskit_consumer`, which the AT-SPI,
910    /// UIA and macOS adapters all read the tree through, reads a hidden node
911    /// as `ExcludeSubtree` and treats a node as hidden when any ancestor is,
912    /// so nothing below it reaches a screen reader except a node that holds
913    /// focus, and that one is not listed among its parent's children. A
914    /// wrapper that is only chrome around content a reader needs (a panel,
915    /// a frame, a layout shell) must not call this: it is a
916    /// `Role::GenericContainer` carrying nothing else, which the walker
917    /// prunes and the adapters drop while keeping its children.
918    pub fn set_hidden(&mut self) {
919        self.hidden = true;
920        self.inner.set_hidden();
921    }
922
923    /// Clear the hidden flag set by an earlier `set_hidden()` call on this
924    /// node. Used by the override layer to re-expose a widget that hid
925    /// itself. It clears this node's own flag only: a node under a hidden
926    /// ancestor stays hidden, because the consumer the platform adapters
927    /// read through inherits the flag from every ancestor.
928    pub fn clear_hidden(&mut self) {
929        self.hidden = false;
930        self.inner.clear_hidden();
931    }
932
933    pub fn is_hidden(&self) -> bool {
934        self.hidden
935    }
936
937    pub fn role(&self) -> Role {
938        self.role
939    }
940
941    pub fn name(&self) -> Option<&str> {
942        self.name.as_deref()
943    }
944
945    pub fn actions(&self) -> &[Action] {
946        &self.actions
947    }
948
949    pub fn value(&self) -> Option<&str> {
950        self.value.as_deref()
951    }
952
953    pub fn toggled(&self) -> Option<bool> {
954        self.toggled
955    }
956
957    /// The node's numeric value (`Node::numeric_value`), as set by the widget
958    /// or an `access_numeric_value` override.
959    pub fn numeric_value(&self) -> Option<f64> {
960        self.inner.numeric_value()
961    }
962
963    /// The node's numeric lower bound (`Node::min_numeric_value`).
964    pub fn min_numeric_value(&self) -> Option<f64> {
965        self.inner.min_numeric_value()
966    }
967
968    /// The node's numeric upper bound (`Node::max_numeric_value`).
969    pub fn max_numeric_value(&self) -> Option<f64> {
970        self.inner.max_numeric_value()
971    }
972
973    /// The node's custom actions, in declaration order (the widget's own
974    /// first, then the application's `access_custom_action` entries).
975    pub fn custom_actions(&self) -> &[accesskit::CustomAction] {
976        self.inner.custom_actions()
977    }
978
979    pub fn expanded(&self) -> Option<bool> {
980        self.expanded
981    }
982
983    pub fn selected(&self) -> Option<bool> {
984        self.selected
985    }
986
987    /// Build the AccessKit Node with the given ID. Resolves any
988    /// `pending_self_selection` recorded via `set_caret_position_on_self`
989    /// or `set_text_selection_on_self` — at this point we know the
990    /// widget's NodeId and can inject it into the text selection.
991    /// Returns the primary `(NodeId, Node)` pair plus any synthetic
992    /// child nodes emitted by the widget via `push_paragraph_child`
993    /// / `push_text_run_child`. The tree walker is responsible for
994    /// merging these into the final `TreeUpdate`.
995    pub fn build(
996        mut self,
997        id: WidgetId,
998    ) -> (
999        NodeId,
1000        Node,
1001        Vec<(NodeId, Node)>,
1002        Vec<(NodeId, teksilo_canvas::Rect)>,
1003    ) {
1004        let node_id = widget_id_to_node_id(id);
1005        // Priority: explicit (child-targeting) selection wins over
1006        // self-targeting selection — widgets that emit TextRun
1007        // children use the explicit path.
1008        if let Some((anchor, focus)) = self.pending_explicit_selection.take() {
1009            let selection = TextSelection { anchor, focus };
1010            self.inner.set_text_selection(selection);
1011        } else if let Some((anchor, focus)) = self.pending_self_selection.take() {
1012            let selection = TextSelection {
1013                anchor: TextPosition {
1014                    node: node_id,
1015                    character_index: anchor,
1016                },
1017                focus: TextPosition {
1018                    node: node_id,
1019                    character_index: focus,
1020                },
1021            };
1022            self.inner.set_text_selection(selection);
1023        }
1024
1025        // accesskit contract: a `Role::Label` node carries its text in the
1026        // `value` property, NOT `label`. Every platform adapter reads it that
1027        // way — Windows UIA derives the node's Name from `value` (its
1028        // `label_comes_from_value()` returns true for `Role::Label`), macOS
1029        // maps `Role::Label` to `NSAccessibilityStaticTextRole` whose content
1030        // is exposed as AXValue, and `accesskit_consumer` reads `value` when
1031        // another control is `labelled_by` this node. A name left in the
1032        // `label` property is therefore silently dropped on Windows and stray
1033        // on macOS. Widgets set the accessible name uniformly via `set_name`
1034        // (-> the `label` property); re-serialize it to `value` here, the one
1035        // place every emitted node is finalized — widget nodes (via the tree
1036        // walker) and scene synthetic children (via `push_scene_child`, which
1037        // also funnels through `build`). The builder's logical `name()` view
1038        // is intentionally left untouched, so introspection / `find_by_label`
1039        // continue to report the accessible name regardless of role. Reading
1040        // the inner node directly keeps this robust against any label set
1041        // outside `set_name`, and idempotent (a second pass finds no label).
1042        if self.inner.role() == Role::Label
1043            && let Some(label) = self.inner.label().map(|s| s.to_string())
1044        {
1045            if self.inner.value().is_none() {
1046                self.inner.set_value(label);
1047            }
1048            self.inner.clear_label();
1049        }
1050
1051        // A role override away from a text-range-capable role leaves any
1052        // runs inert: no platform exposes them, and they would still cost
1053        // a node in every update and a child stop the walker has to
1054        // reconcile. Drop them rather than ship them.
1055        // `Role::Unknown` is exempt: it is the builder's initial value, so
1056        // dropping there would punish a caller that never set a role at all
1057        // rather than one that set a role text ranges cannot live under.
1058        // Such a node is pruned by the walker in any case.
1059        if !self.children_collected.is_empty()
1060            && self.inner.role() != Role::Unknown
1061            && !role_supports_text_ranges(self.inner.role())
1062            && let Some(run_ids) = own_run_ids(&self.inner, &self.children_collected)
1063        {
1064            self.children_collected
1065                .retain(|(cid, _)| !run_ids.contains(cid));
1066            self.child_local_bounds
1067                .retain(|(cid, _)| !run_ids.contains(cid));
1068            let kept: Vec<NodeId> = self
1069                .inner
1070                .children()
1071                .iter()
1072                .copied()
1073                .filter(|cid| !run_ids.contains(cid))
1074                .collect();
1075            self.inner.set_children(kept);
1076        }
1077
1078        // Synthetic children declared in the widget's own space become
1079        // absolute here: the walker has already written the owner's
1080        // window-space rect onto `inner`, and this is the only point at
1081        // which both halves are in hand.
1082        let origin = self
1083            .inner
1084            .bounds()
1085            .map(|r| (r.x0, r.y0))
1086            .unwrap_or((0.0, 0.0));
1087        let local_bounds = std::mem::take(&mut self.child_local_bounds);
1088        for (child_id, local) in &local_bounds {
1089            let absolute = accesskit::Rect {
1090                x0: origin.0 + local.x as f64,
1091                y0: origin.1 + local.y as f64,
1092                x1: origin.0 + (local.x + local.width) as f64,
1093                y1: origin.1 + (local.y + local.height) as f64,
1094            };
1095            for (id, node) in self.children_collected.iter_mut() {
1096                if id == child_id {
1097                    node.set_bounds(absolute);
1098                    break;
1099                }
1100            }
1101        }
1102
1103        (node_id, self.inner, self.children_collected, local_bounds)
1104    }
1105
1106    /// Get a reference to the inner node for advanced use.
1107    pub fn inner_mut(&mut self) -> &mut Node {
1108        &mut self.inner
1109    }
1110
1111    /// The widget id this builder was constructed for, if any. Set
1112    /// by [`AccessNodeBuilder::for_widget`]; used by the scene-tree
1113    /// walker to derive synthetic `NodeId`s for items / groups outside
1114    /// the closure form (`push_scene_child*`).
1115    pub fn owner_id(&self) -> Option<crate::widget_id::WidgetId> {
1116        self.owner
1117    }
1118
1119    /// Run a mutator over a synthetic child node previously pushed
1120    /// via `push_scene_child` (or its `_under` variant). Used by
1121    /// the scene walker to apply cross-tree decorations (relations /
1122    /// live regions / landmarks) after the initial hierarchy emit.
1123    /// Returns `true` if the node was found.
1124    ///
1125    /// Cannot be used to mutate widget-derived NodeIds — those live
1126    /// in the global TreeUpdate and are owned by other widgets.
1127    pub fn with_collected_node<F: FnOnce(&mut Node)>(&mut self, node_id: NodeId, f: F) -> bool {
1128        for (id, node) in self.children_collected.iter_mut() {
1129            if *id == node_id {
1130                f(node);
1131                return true;
1132            }
1133        }
1134        false
1135    }
1136
1137    /// Mark this node as read-only. Used by `RichTextEditor::read_only` so
1138    /// screen readers announce the widget as a document rather than a form
1139    /// field.
1140    pub fn set_read_only(&mut self) {
1141        self.inner.set_read_only();
1142    }
1143
1144    /// Declare the current text selection. `anchor` and `focus` are
1145    /// character indices into the widget's flat text representation; pass
1146    /// equal indices for a collapsed caret. Uses the same `NodeId` for
1147    /// both positions (typical for single-node text widgets that expose
1148    /// the document as one run, which is what the first milestone of
1149    /// `RichTextEditor` does).
1150    pub fn set_text_selection(&mut self, node_id: NodeId, anchor: usize, focus: usize) {
1151        let selection = TextSelection {
1152            anchor: TextPosition {
1153                node: node_id,
1154                character_index: anchor,
1155            },
1156            focus: TextPosition {
1157                node: node_id,
1158                character_index: focus,
1159            },
1160        };
1161        self.inner.set_text_selection(selection);
1162    }
1163
1164    /// Convenience for exposing a caret position as a collapsed selection.
1165    pub fn set_caret_position(&mut self, node_id: NodeId, character_index: usize) {
1166        self.set_text_selection(node_id, character_index, character_index);
1167    }
1168
1169    /// Declare a text selection whose anchor and focus live on the
1170    /// widget's own AccessKit node. The widget doesn't know its own
1171    /// `NodeId` inside `accessibility(&self, builder)` — it's only
1172    /// resolved when the tree walker calls `builder.build(widget_id)`.
1173    /// This method stashes the character indices and defers the
1174    /// `set_text_selection` call until `build()` knows the ID.
1175    pub fn set_text_selection_on_self(&mut self, anchor: usize, focus: usize) {
1176        self.pending_self_selection = Some((anchor, focus));
1177    }
1178
1179    /// Convenience wrapper for a collapsed caret on the widget's own node.
1180    pub fn set_caret_position_on_self(&mut self, character_index: usize) {
1181        self.set_text_selection_on_self(character_index, character_index);
1182    }
1183
1184    // ── Sub-tree API: multi-node widgets (rich text, etc.) ─────────────
1185
1186    /// Push a `Role::Paragraph` child on the current node and return
1187    /// its `NodeId`. The NodeId is synthetic (bit 63 set) and
1188    /// deterministic given the owning widget + `element_id`.
1189    ///
1190    /// The owning `WidgetId` comes from the builder's `owner`
1191    /// field, set by `AccessNodeBuilder::for_widget`. Returns
1192    /// `NodeId(0)` (a no-op placeholder) if the builder has no
1193    /// owner, which can only happen when a widget constructs a
1194    /// builder manually via `new()` instead of going through the
1195    /// tree walker. That's a programming error worth catching in
1196    /// debug.
1197    pub fn push_paragraph_child(&mut self, element_id: u64) -> NodeId {
1198        let Some(owner) = self.owner else {
1199            debug_assert!(
1200                false,
1201                "push_paragraph_child called on a builder with no owner — \
1202                 widgets must only call this from Widget::accessibility"
1203            );
1204            return NodeId(0);
1205        };
1206        let node_id = synthetic_node_id(owner, element_id, SyntheticKind::Paragraph);
1207        let node = Node::new(Role::Paragraph);
1208        self.children_collected.push((node_id, node));
1209        self.inner.push_child(node_id);
1210        node_id
1211    }
1212
1213    /// Push a `Role::Comment` child carrying an annotation's text, and return its
1214    /// `NodeId` so the annotated run can point at it via [`Self::push_detail`].
1215    ///
1216    /// `group_id` must be the annotation's own durable identity (a comment's uid,
1217    /// never a store id), so the node keeps the same `NodeId` across rebuilds and
1218    /// a screen reader's cursor is not thrown out of the thread by an unrelated
1219    /// edit elsewhere in the document.
1220    ///
1221    /// Per the W3C annotations pattern the *body* carries the name; the annotated
1222    /// span itself must NOT be given an accessible name (`role="mark"` forbids it)
1223    /// — naming the span would make the reader announce the comment's text in
1224    /// place of the prose.
1225    pub fn push_annotation_child(&mut self, group_id: u64, text: impl Into<String>) -> NodeId {
1226        let Some(owner) = self.owner else {
1227            debug_assert!(
1228                false,
1229                "push_annotation_child called on a builder with no owner — \
1230                 widgets must only call this from Widget::accessibility"
1231            );
1232            return NodeId(0);
1233        };
1234        let node_id = synthetic_node_id(owner, group_id, SyntheticKind::Annotation);
1235        let mut node = Node::new(Role::Comment);
1236        node.set_value(text.into());
1237        self.children_collected.push((node_id, node));
1238        self.inner.push_child(node_id);
1239        node_id
1240    }
1241
1242    /// Add a `details` target to an already-pushed **child** node.
1243    ///
1244    /// The sub-tree API builds children eagerly into `children_collected`, so a
1245    /// relation between two synthetic siblings (a `TextRun` and its annotation
1246    /// body) cannot go through the current node's own setters — it has to reach
1247    /// back into the collected child. A no-op if `child` was never pushed, which
1248    /// keeps a caller that emitted spans for a run it then skipped from panicking.
1249    pub fn push_detail_on_child(&mut self, child: NodeId, detail: NodeId) {
1250        if let Some((_, node)) = self
1251            .children_collected
1252            .iter_mut()
1253            .find(|(id, _)| *id == child)
1254        {
1255            node.push_detail(detail);
1256        }
1257    }
1258
1259    /// Push a `Role::Link` child on the current node. Used by label
1260    /// widgets (e.g. `TextWidget` with `.markup(true)` enabled) to
1261    /// expose inline `[label](url)` links as individual accessible
1262    /// nodes alongside the parent's own text.
1263    ///
1264    /// `element_id` should be a stable identifier for the link inside
1265    /// the parent widget (typically the byte offset of the `[` in the
1266    /// original markup source, so the NodeId survives identical
1267    /// re-layouts).
1268    ///
1269    /// The returned `NodeId` is synthetic (bit 63 set) and deterministic
1270    /// given `(owner, element_id)`.
1271    pub fn push_link_child(
1272        &mut self,
1273        element_id: u64,
1274        label: impl Into<String>,
1275        url: impl Into<String>,
1276    ) -> NodeId {
1277        let Some(owner) = self.owner else {
1278            debug_assert!(
1279                false,
1280                "push_link_child called on a builder with no owner — \
1281                 widgets must only call this from Widget::accessibility"
1282            );
1283            return NodeId(0);
1284        };
1285        let node_id = synthetic_node_id(owner, element_id, SyntheticKind::Link);
1286        let mut node = Node::new(Role::Link);
1287        let label: String = label.into();
1288        if !label.is_empty() {
1289            node.set_label(label);
1290        }
1291        // AccessKit exposes the link target through the `Value` property
1292        // on a `Role::Link` node — same convention the standalone
1293        // `Link` widget uses via `set_value(...)`.
1294        node.set_value(url.into());
1295        self.children_collected.push((node_id, node));
1296        self.inner.push_child(node_id);
1297        node_id
1298    }
1299
1300    /// Push a synthetic child node representing a lightweight
1301    /// `SceneItem` (or `SceneGroup`) emitted by `teksilo_scene::SceneView`.
1302    /// The caller customizes a sub-`AccessNodeBuilder` (mirroring the
1303    /// `Widget::accessibility` shape) and gets back the
1304    /// deterministic synthetic `NodeId` allocated for the
1305    /// `(owner, element_id, kind)` tuple.
1306    ///
1307    /// `kind` must be one of the synthetic kinds this path
1308    /// allocates: [`SyntheticKind::SceneItem`],
1309    /// [`SyntheticKind::SceneGroup`], [`SyntheticKind::SceneMagnet`],
1310    /// [`SyntheticKind::SceneHandle`], [`SyntheticKind::ChartMark`] or
1311    /// [`SyntheticKind::LaneMark`];
1312    /// passing any other variant panics in debug. The last two are
1313    /// how a chart or a margin lane emits one node per datum from
1314    /// its own `accessibility()`.
1315    ///
1316    /// Any further synthetic children the closure pushes (a
1317    /// `SceneGroup` containing nested `SceneItem`s) are forwarded into the parent's
1318    /// `children_collected` and re-parented under the
1319    /// just-pushed node via the closure's own `inner.push_child`
1320    /// calls — same convention as `push_paragraph_child` →
1321    /// `push_text_run_child`.
1322    pub fn push_scene_child(
1323        &mut self,
1324        element_id: u64,
1325        kind: SyntheticKind,
1326        customize: impl FnOnce(&mut AccessNodeBuilder),
1327    ) -> NodeId {
1328        debug_assert!(
1329            matches!(
1330                kind,
1331                SyntheticKind::SceneItem
1332                    | SyntheticKind::SceneGroup
1333                    | SyntheticKind::SceneMagnet
1334                    | SyntheticKind::SceneHandle
1335                    | SyntheticKind::ChartMark
1336                    | SyntheticKind::LaneMark
1337                    | SyntheticKind::WebPageNode
1338            ),
1339            "push_scene_child requires SyntheticKind::SceneItem, ::SceneGroup, ::SceneMagnet, ::SceneHandle, ::ChartMark, ::LaneMark or ::WebPageNode"
1340        );
1341        let Some(owner) = self.owner else {
1342            debug_assert!(
1343                false,
1344                "push_scene_child called on a builder with no owner — \
1345                 widgets must only call this from Widget::accessibility"
1346            );
1347            return NodeId(0);
1348        };
1349        let node_id = synthetic_node_id(owner, element_id, kind);
1350        // Build the child against a fresh sub-builder so the item
1351        // sees the same `&mut AccessNodeBuilder` shape as widgets.
1352        // Owner-id is the SceneView's so further `push_scene_child`
1353        // calls inside the customize closure (a `SceneGroup`
1354        // emitting nested items) hash off the same owner.
1355        let mut child_builder = AccessNodeBuilder::for_widget(owner);
1356        customize(&mut child_builder);
1357        // `build(owner)` re-derives a widget-keyed NodeId we throw
1358        // away — we use our synthetic `node_id` instead. The
1359        // returned `Node` carries the role / label / bounds / etc
1360        // the customize closure populated; any *grand*children the
1361        // closure pushed via further `push_scene_child` calls come
1362        // back in the third tuple field and we forward them so the
1363        // main TreeUpdate sees the full subtree.
1364        let (_unused, node, grand_children, _local) = child_builder.build(owner);
1365        self.children_collected.push((node_id, node));
1366        for (gid, gnode) in grand_children {
1367            self.children_collected.push((gid, gnode));
1368        }
1369        self.inner.push_child(node_id);
1370        node_id
1371    }
1372
1373    /// Append an existing synthetic node id as a child of a
1374    /// previously-pushed `SceneGroup` (or `SceneItem`) child. Used by
1375    /// the scene logical-tree walker to re-parent items under their
1376    /// declared logical group rather than as direct children of the
1377    /// SceneView.
1378    ///
1379    /// Returns `true` if the parent was found (and the child was
1380    /// attached), `false` if the parent isn't in
1381    /// `children_collected` — the caller misordered the pushes.
1382    pub fn attach_scene_child_under(&mut self, parent: NodeId, child: NodeId) -> bool {
1383        for (id, node) in self.children_collected.iter_mut() {
1384            if *id == parent {
1385                node.push_child(child);
1386                return true;
1387            }
1388        }
1389        false
1390    }
1391
1392    /// Like `push_scene_child` but lets the caller pick the
1393    /// parent. `parent = None` attaches to the widget's own node
1394    /// (same behavior as `push_scene_child`); `parent = Some(...)`
1395    /// attaches to the previously-pushed scene-child with that id.
1396    /// The scene logical-tree walker uses this to nest scene items
1397    /// under declared `A11yGroup` parents.
1398    ///
1399    /// Returns the deterministic synthetic `NodeId` for the new
1400    /// child. If `parent` was `Some` but the parent wasn't found
1401    /// in `children_collected`, the child still gets created and
1402    /// recorded but ends up attached to the widget's own node as a
1403    /// fallback (and a debug-assert fires).
1404    pub fn push_scene_child_under(
1405        &mut self,
1406        parent: Option<NodeId>,
1407        element_id: u64,
1408        kind: SyntheticKind,
1409        customize: impl FnOnce(&mut AccessNodeBuilder),
1410    ) -> NodeId {
1411        debug_assert!(
1412            matches!(
1413                kind,
1414                SyntheticKind::SceneItem
1415                    | SyntheticKind::SceneGroup
1416                    | SyntheticKind::SceneMagnet
1417                    | SyntheticKind::SceneHandle
1418                    | SyntheticKind::ChartMark
1419                    | SyntheticKind::LaneMark
1420                    | SyntheticKind::WebPageNode
1421            ),
1422            "push_scene_child_under requires SyntheticKind::SceneItem, ::SceneGroup, ::SceneMagnet, ::SceneHandle, ::ChartMark, ::LaneMark or ::WebPageNode"
1423        );
1424        let Some(owner) = self.owner else {
1425            debug_assert!(
1426                false,
1427                "push_scene_child_under called on a builder with no owner — \
1428                 widgets must only call this from Widget::accessibility"
1429            );
1430            return NodeId(0);
1431        };
1432        let node_id = synthetic_node_id(owner, element_id, kind);
1433        let mut child_builder = AccessNodeBuilder::for_widget(owner);
1434        customize(&mut child_builder);
1435        let (_unused, node, grand_children, _local) = child_builder.build(owner);
1436        self.children_collected.push((node_id, node));
1437        for (gid, gnode) in grand_children {
1438            self.children_collected.push((gid, gnode));
1439        }
1440        match parent {
1441            Some(parent_id) => {
1442                let attached = self.attach_scene_child_under(parent_id, node_id);
1443                if !attached {
1444                    debug_assert!(
1445                        false,
1446                        "push_scene_child_under: parent {:?} not in children_collected — \
1447                         caller must push the parent before its children",
1448                        parent_id
1449                    );
1450                    self.inner.push_child(node_id);
1451                }
1452            }
1453            None => {
1454                self.inner.push_child(node_id);
1455            }
1456        }
1457        node_id
1458    }
1459
1460    /// Override a previously-pushed paragraph child's role to
1461    /// `Role::Heading` with the given hierarchical level. Used by
1462    /// the rich text editor when a block carries a
1463    /// `BlockFormat::heading_level`. Returns `true` if the node was
1464    /// found and updated, `false` otherwise (caller misused the
1465    /// api — the paragraph must have been pushed earlier).
1466    pub fn set_paragraph_as_heading(&mut self, node_id: NodeId, level: u8) -> bool {
1467        for (id, node) in self.children_collected.iter_mut() {
1468            if *id == node_id {
1469                node.set_role(Role::Heading);
1470                // AccessKit's `set_level` takes a usize (via the
1471                // usize_property_methods macro). Clamp to 1..=6 for
1472                // conventional heading semantics.
1473                // Clamped to the conventional 1..=6 heading range, then
1474                // converted: AccessKit's `level` is zero-based, so an H1 is 0.
1475                // Writing the 1-based number straight through made every
1476                // heading announce one level too deep on Windows, and made
1477                // "heading level 1" unreachable.
1478                let level: usize = to_accesskit_ordinal((level as usize).clamp(1, 6));
1479                node.set_level(level);
1480                return true;
1481            }
1482        }
1483        false
1484    }
1485
1486    /// Set the **1-based** position-in-set on a previously-pushed synthetic
1487    /// child (a paragraph, "line 42 of 200"), and the set size on this widget's
1488    /// own node, which is the container the child hangs from.
1489    ///
1490    /// AccessKit exposes `position_in_set` on every node, but
1491    /// [`set_position_in_set`](Self::set_position_in_set) only touches the
1492    /// widget's own node. This reaches a collected child by NodeId, the same
1493    /// way [`set_paragraph_as_heading`](Self::set_paragraph_as_heading) does,
1494    /// and applies the same 1-based-to-zero-based conversion.
1495    ///
1496    /// `size` deliberately lands on the parent rather than the child: AccessKit
1497    /// resolves a set size by walking up from the item, so a size written on
1498    /// the child is read by nobody. See
1499    /// [`set_size_of_set`](Self::set_size_of_set).
1500    ///
1501    /// Returns whether the child was found.
1502    pub fn set_child_position_in_set(
1503        &mut self,
1504        node_id: NodeId,
1505        position: usize,
1506        size: usize,
1507    ) -> bool {
1508        let found = self.with_collected_node(node_id, |node| {
1509            node.set_position_in_set(to_accesskit_ordinal(position));
1510        });
1511        if found {
1512            self.inner.set_size_of_set(size);
1513        }
1514        found
1515    }
1516
1517    /// Declare this node's base reading direction.
1518    ///
1519    /// AccessKit's text APIs read the direction from the *run*; the root
1520    /// carries it so a consumer that asks the container — and every
1521    /// platform that maps a paragraph direction onto its own attribute —
1522    /// gets an answer for an empty or geometry-less node too.
1523    pub fn set_text_direction(&mut self, direction: accesskit::TextDirection) {
1524        self.inner.set_text_direction(direction);
1525    }
1526
1527    /// Set the reading direction of a synthetic child pushed earlier.
1528    /// Returns `true` if the child was found.
1529    pub fn set_child_text_direction(
1530        &mut self,
1531        child: NodeId,
1532        direction: accesskit::TextDirection,
1533    ) -> bool {
1534        self.with_collected_node(child, |node| node.set_text_direction(direction))
1535    }
1536
1537    /// Declare a synthetic child's bounds in the **owner's own**
1538    /// coordinate space; [`build`](Self::build) translates them into
1539    /// window space once the owner's absolute rect is known.
1540    ///
1541    /// This is what a widget should use for geometry it derives from its
1542    /// own layout — a label's line boxes, an editor's rows. A widget
1543    /// holding rects that are *already* absolute (a scene item under a
1544    /// view transform) calls `set_bounds` on the child node instead and
1545    /// never comes through here.
1546    ///
1547    /// Returns `true` if the child was found.
1548    pub fn set_child_bounds_local(&mut self, child: NodeId, rect: teksilo_canvas::Rect) -> bool {
1549        if !self.children_collected.iter().any(|(id, _)| *id == child) {
1550            return false;
1551        }
1552        self.child_local_bounds.push((child, rect));
1553        true
1554    }
1555
1556    /// Link a run of `Role::TextRun` children as one visual line, so assistive
1557    /// technology navigating by line treats them as a continuous line rather
1558    /// than fracturing at each formatting or chunk boundary.
1559    ///
1560    /// Sets each run's `next_on_line` to its successor and each successor's
1561    /// `previous_on_line` to its predecessor (AccessKit's doubly-linked
1562    /// same-line chain); the first run keeps no `previous_on_line` and the last
1563    /// no `next_on_line`, which is how the consumer detects the line's ends. A
1564    /// slice of zero or one is a no-op. Every id must be a run pushed earlier via
1565    /// [`push_text_run`](Self::push_text_run) — or the older
1566    /// [`push_text_run_child`](Self::push_text_run_child).
1567    pub fn link_runs_on_line(&mut self, run_ids: &[NodeId]) {
1568        for pair in run_ids.windows(2) {
1569            let (a, b) = (pair[0], pair[1]);
1570            self.with_collected_node(a, |node| node.set_next_on_line(b));
1571            self.with_collected_node(b, |node| node.set_previous_on_line(a));
1572        }
1573    }
1574
1575    /// Attach an already-built synthetic child under `parent` (another
1576    /// collected child) or under the widget's own node.
1577    ///
1578    /// Returns `None` when `node_id` was already pushed: a duplicate child id
1579    /// panics `accesskit_consumer`'s tree builder, so it is dropped here with
1580    /// a diagnostic instead — the rule [`Self::push_text_run`] follows. The
1581    /// owner check belongs to the callers, which need it to derive `node_id`
1582    /// in the first place.
1583    fn push_collected_child(
1584        &mut self,
1585        parent: Option<NodeId>,
1586        node_id: NodeId,
1587        node: Node,
1588    ) -> Option<NodeId> {
1589        if self.children_collected.iter().any(|(id, _)| *id == node_id) {
1590            debug_assert!(
1591                false,
1592                "Teksilo bug: two accessibility children of widget {:?} derived \
1593                 the same node id {node_id:?}. Please file a bug report.",
1594                self.owner
1595            );
1596            // Paired with an `eprintln!` for the same reason `push_text_run`
1597            // has one: the `debug_assert!` compiles out, and a silent drop
1598            // here loses a whole subtree — a table row and every character in
1599            // it — with nothing to show for it in a shipped build.
1600            eprintln!(
1601                "Teksilo bug: two accessibility children of widget {:?} derived \
1602                 the same node id {node_id:?}; the second was dropped. Please \
1603                 file a bug report.",
1604                self.owner
1605            );
1606            return None;
1607        }
1608        self.children_collected.push((node_id, node));
1609        match parent {
1610            Some(parent_node) => {
1611                for (id, collected) in self.children_collected.iter_mut() {
1612                    if *id == parent_node {
1613                        collected.push_child(node_id);
1614                        return Some(node_id);
1615                    }
1616                }
1617                // Parent not found — attach to the widget's own node rather
1618                // than orphaning the child. Caller misused the API.
1619                self.inner.push_child(node_id);
1620            }
1621            None => self.inner.push_child(node_id),
1622        }
1623        Some(node_id)
1624    }
1625
1626    /// Push a `Role::Table` child carrying its dimensions, under `parent`
1627    /// when given and under the widget's own node otherwise.
1628    ///
1629    /// `element_id` must be the document's own durable table id, so the node
1630    /// keeps its `NodeId` across edits and a screen reader's cursor is not
1631    /// thrown out of the table by an unrelated change elsewhere.
1632    pub fn push_table_child(
1633        &mut self,
1634        parent: Option<NodeId>,
1635        element_id: u64,
1636        rows: usize,
1637        columns: usize,
1638    ) -> Option<NodeId> {
1639        let owner = self.owner?;
1640        let node_id = synthetic_node_id(owner, element_id, SyntheticKind::RichTextTable);
1641        let mut node = Node::new(Role::Table);
1642        node.set_row_count(rows);
1643        node.set_column_count(columns);
1644        self.push_collected_child(parent, node_id, node)
1645    }
1646
1647    /// Push a `Role::Row` child under a table pushed by
1648    /// [`Self::push_table_child`].
1649    ///
1650    /// **1-based** `row_index`, the ARIA `aria-rowindex` convention this
1651    /// builder's whole public surface uses — so the first row is 1, exactly as
1652    /// for [`Self::set_row_index`]. The conversion to the zero-based number
1653    /// AccessKit stores happens here, at the same boundary every other ordinal
1654    /// on this builder is converted at.
1655    pub fn push_table_row_child(
1656        &mut self,
1657        parent: NodeId,
1658        element_id: u64,
1659        row_index: usize,
1660    ) -> Option<NodeId> {
1661        let owner = self.owner?;
1662        let node_id = synthetic_node_id(owner, element_id, SyntheticKind::RichTextTableRow);
1663        let mut node = Node::new(Role::Row);
1664        node.set_row_index(to_accesskit_ordinal(row_index));
1665        self.push_collected_child(Some(parent), node_id, node)
1666    }
1667
1668    /// Push a `Role::Cell` child under a row pushed by
1669    /// [`Self::push_table_row_child`].
1670    ///
1671    /// **1-based** `row_index` / `column_index` (see
1672    /// [`Self::push_table_row_child`]); the spans are plain counts and are
1673    /// written only when they exceed 1, so an ordinary cell carries no
1674    /// span properties at all.
1675    pub fn push_table_cell_child(
1676        &mut self,
1677        parent: NodeId,
1678        element_id: u64,
1679        row_index: usize,
1680        column_index: usize,
1681        row_span: usize,
1682        column_span: usize,
1683    ) -> Option<NodeId> {
1684        let owner = self.owner?;
1685        let node_id = synthetic_node_id(owner, element_id, SyntheticKind::RichTextTableCell);
1686        let mut node = Node::new(Role::Cell);
1687        node.set_row_index(to_accesskit_ordinal(row_index));
1688        node.set_column_index(to_accesskit_ordinal(column_index));
1689        if row_span > 1 {
1690            node.set_row_span(row_span);
1691        }
1692        if column_span > 1 {
1693            node.set_column_span(column_span);
1694        }
1695        self.push_collected_child(Some(parent), node_id, node)
1696    }
1697
1698    /// Push the `Role::Label` text container inside a cell, and return it so
1699    /// the cell's text runs can be pushed under it.
1700    ///
1701    /// See [`SyntheticKind::RichTextCellText`] for why the runs may not hang
1702    /// off the `Role::Cell` directly.
1703    ///
1704    /// The container is deliberately given no value of its own: the text is
1705    /// carried by the runs beneath it, which is how every other text surface
1706    /// in the framework exposes its content, and duplicating it here would
1707    /// have a reader announce the cell twice.
1708    pub fn push_cell_text_child(&mut self, parent: NodeId, element_id: u64) -> Option<NodeId> {
1709        let owner = self.owner?;
1710        let node_id = synthetic_node_id(owner, element_id, SyntheticKind::RichTextCellText);
1711        let node = Node::new(Role::Label);
1712        self.push_collected_child(Some(parent), node_id, node)
1713    }
1714
1715    /// Push the `Role::Label` text container inside a structural block-level
1716    /// node, and return it so that block's text runs can be pushed under it.
1717    ///
1718    /// See [`SyntheticKind::RichTextBlockText`]. A heading keeps its own
1719    /// `Role::Heading` node — it is how a reader jumps through a document —
1720    /// and a blockquote keeps its `Role::Blockquote`; this sits between either
1721    /// and the runs so the text changes beneath still reach the platform.
1722    ///
1723    /// `element_id` is the **block's** id, so a heading nested in a blockquote
1724    /// still produces exactly one container.
1725    pub fn push_block_text_child(&mut self, parent: NodeId, element_id: u64) -> Option<NodeId> {
1726        let owner = self.owner?;
1727        let node_id = synthetic_node_id(owner, element_id, SyntheticKind::RichTextBlockText);
1728        let node = Node::new(Role::Label);
1729        self.push_collected_child(Some(parent), node_id, node)
1730    }
1731
1732    /// Push a `Role::Blockquote` child, under `parent` when given and under
1733    /// the widget's own node otherwise.
1734    ///
1735    /// `element_id` must be the document's own frame id, so the node keeps its
1736    /// `NodeId` across edits.
1737    pub fn push_blockquote_child(
1738        &mut self,
1739        parent: Option<NodeId>,
1740        element_id: u64,
1741    ) -> Option<NodeId> {
1742        let owner = self.owner?;
1743        let node_id = synthetic_node_id(owner, element_id, SyntheticKind::RichTextBlockquote);
1744        let node = Node::new(Role::Blockquote);
1745        self.push_collected_child(parent, node_id, node)
1746    }
1747
1748    /// Push one `Role::TextRun` child, under `parent` when given and
1749    /// under the widget's own node otherwise.
1750    ///
1751    /// The single door every text run in the framework goes through.
1752    /// Returns `None` when the builder has no owner (so no id can be
1753    /// derived) or when the id it derived is already taken — a duplicate
1754    /// child id panics `accesskit_consumer`'s tree builder, so it is
1755    /// dropped here with a diagnostic instead.
1756    ///
1757    /// Prefer [`text_runs::push_text_runs`], which owns the chunking,
1758    /// the word segmentation, the hard-break rule and the line links;
1759    /// this is the primitive underneath it.
1760    pub fn push_text_run(&mut self, parent: Option<NodeId>, spec: TextRunSpec) -> Option<NodeId> {
1761        let owner = self.owner?;
1762        let node_id = synthetic_node_id(owner, spec.element_id, SyntheticKind::TextRun);
1763        if let Some((existing, _)) = self
1764            .children_collected
1765            .iter()
1766            .find(|(id, _)| *id == node_id)
1767        {
1768            debug_assert!(
1769                false,
1770                "Teksilo bug: two text runs of widget {owner:?} derived the same \
1771                 accessibility node id {existing:?}. Give each source its own \
1772                 `TextRunSource::id_seed`. Please file a bug report."
1773            );
1774            eprintln!(
1775                "Teksilo bug: two text runs of widget {owner:?} derived the same \
1776                 accessibility node id {existing:?}; the second was dropped. \
1777                 Please file a bug report."
1778            );
1779            return None;
1780        }
1781
1782        let TextRunSpec {
1783            value,
1784            character_lengths,
1785            word_starts,
1786            character_positions,
1787            character_widths,
1788            bounds,
1789            bounds_are_absolute,
1790            text_direction,
1791            attrs,
1792            ..
1793        } = spec;
1794
1795        debug_assert_eq!(
1796            character_lengths.iter().map(|n| *n as usize).sum::<usize>(),
1797            value.len(),
1798            "AccessKit requires the character lengths of a text run to sum to its value's byte length"
1799        );
1800        let mut node = Node::new(Role::TextRun);
1801        node.set_value(value);
1802        let expected = character_lengths.len();
1803        node.set_character_lengths(character_lengths);
1804        node.set_word_starts(word_starts);
1805        // All four or none: `Range::bounding_boxes()` throws away every box
1806        // it has already collected the moment one run is missing any of
1807        // them, so a half-populated run empties the geometry of every
1808        // range that touches it.
1809        if character_positions.len() == expected && character_widths.len() == expected {
1810            node.set_character_positions(character_positions);
1811            node.set_character_widths(character_widths);
1812        }
1813        node.set_text_direction(text_direction);
1814        if bounds_are_absolute {
1815            node.set_bounds(accesskit::Rect {
1816                x0: bounds.x as f64,
1817                y0: bounds.y as f64,
1818                x1: (bounds.x + bounds.width) as f64,
1819                y1: (bounds.y + bounds.height) as f64,
1820            });
1821        }
1822        apply_run_attrs(&mut node, attrs);
1823
1824        self.children_collected.push((node_id, node));
1825        if !bounds_are_absolute {
1826            self.child_local_bounds.push((node_id, bounds));
1827        }
1828
1829        match parent {
1830            Some(parent_node) => {
1831                for (id, node) in self.children_collected.iter_mut() {
1832                    if *id == parent_node {
1833                        node.push_child(node_id);
1834                        return Some(node_id);
1835                    }
1836                }
1837                // Parent not found — attach to the widget's own node
1838                // rather than orphaning the run. Caller misused the API.
1839                self.inner.push_child(node_id);
1840            }
1841            None => self.inner.push_child(node_id),
1842        }
1843        Some(node_id)
1844    }
1845
1846    /// Push a `Role::TextRun` child under `parent_node` (usually a
1847    /// paragraph NodeId returned from `push_paragraph_child`, but
1848    /// may also be the widget's own node for inline editors).
1849    ///
1850    /// `element_id` is the stable id of the underlying text-document
1851    /// inline element; combined with `parent_widget` and a
1852    /// disambiguator it produces a synthetic NodeId that survives
1853    /// edits. `fragment_offset` is the block-relative character
1854    /// offset of this run — used as the disambiguator so two
1855    /// highlight-split sub-runs sharing one source element don't
1856    /// collide.
1857    ///
1858    /// `character_lengths` must be the UTF-8 byte length of each
1859    /// character in `value`, per AccessKit's contract. Optional
1860    /// `word_starts`, `character_positions`, and `character_widths`
1861    /// populate the corresponding AccessKit properties.
1862    ///
1863    /// Returns the allocated synthetic `NodeId` so the caller can
1864    /// reference it later when attaching a `TextSelection` via
1865    /// `set_text_selection_to`.
1866    #[allow(clippy::too_many_arguments)]
1867    pub fn push_text_run_child(
1868        &mut self,
1869        parent_node: NodeId,
1870        element_id: u64,
1871        fragment_offset: usize,
1872        value: String,
1873        character_lengths: Vec<u8>,
1874        word_starts: Option<Vec<u8>>,
1875        character_positions: Option<Vec<f32>>,
1876        character_widths: Option<Vec<f32>>,
1877        attrs: TextRunAttributes,
1878    ) -> NodeId {
1879        let Some(owner) = self.owner else {
1880            debug_assert!(
1881                false,
1882                "push_text_run_child called on a builder with no owner — \
1883                 widgets must only call this from Widget::accessibility"
1884            );
1885            return NodeId(0);
1886        };
1887        // Give sub-runs of one source element (a highlight split, or a run
1888        // chunked to stay under the AccessKit word-start cap) distinct NodeIds.
1889        // A plain `element_id ^ (fragment_offset << 32)` would XOR the offset
1890        // into the very bits `element_id` already uses to encode the owning
1891        // block, so a chunk at offset 255 in block A could alias a whole-line run
1892        // in a block whose id is `A ^ 255`. Hashing the offset across all 64 bits
1893        // removes that structure; `fragment_offset == 0` (the whole-run common
1894        // case) stays a no-op, so those NodeIds are unchanged.
1895        let mixed_element = if fragment_offset == 0 {
1896            element_id
1897        } else {
1898            fnv_mix_u64(element_id, fragment_offset as u64, 0)
1899        };
1900        let node_id = synthetic_node_id(owner, mixed_element, SyntheticKind::TextRun);
1901        let mut node = Node::new(Role::TextRun);
1902        node.set_value(value);
1903        node.set_character_lengths(character_lengths);
1904        if let Some(ws) = word_starts {
1905            node.set_word_starts(ws);
1906        }
1907        if let Some(pos) = character_positions {
1908            node.set_character_positions(pos);
1909        }
1910        if let Some(widths) = character_widths {
1911            node.set_character_widths(widths);
1912        }
1913        // Text attributes (WCAG 1.3.1 / EN 301 549 11.5.2.9). AccessKit has no
1914        // bold flag, so an explicit weight wins, else bold => 700.
1915        if let Some(w) = attrs.font_weight {
1916            node.set_font_weight(w as f32);
1917        } else if attrs.bold {
1918            node.set_font_weight(700.0);
1919        }
1920        if attrs.italic {
1921            node.set_italic();
1922        }
1923        if attrs.underline {
1924            node.set_underline(default_text_decoration());
1925        }
1926        if attrs.strikethrough {
1927            node.set_strikethrough(default_text_decoration());
1928        }
1929        self.children_collected.push((node_id, node));
1930        // Attach the text-run to its parent paragraph's child list.
1931        // The parent must already be in `children_collected`.
1932        for (id, parent) in self.children_collected.iter_mut() {
1933            if *id == parent_node {
1934                parent.push_child(node_id);
1935                return node_id;
1936            }
1937        }
1938        // Parent not found — push as a direct child of the widget's
1939        // own node as a fallback. Caller misused the API.
1940        self.inner.push_child(node_id);
1941        node_id
1942    }
1943
1944    /// Push a single `Role::TextRun` child attached **directly** to the
1945    /// widget's own node (no intervening `Role::Paragraph`). This is the
1946    /// single-line text-input shape: `Role::TextInput` → one
1947    /// `Role::TextRun`.
1948    ///
1949    /// Required for screen-reader typing echo. accesskit_consumer's
1950    /// `supports_text_ranges()` returns `false` for a text input that
1951    /// only sets `character_lengths` on its *own* node — it needs a
1952    /// `Role::TextRun` child. Without it the macOS adapter never emits
1953    /// `AXSelectedTextChanged`, so VoiceOver reads the value once on
1954    /// focus but never echoes characters/words while typing. Emit this
1955    /// even when `value` / `character_lengths` are empty so
1956    /// `supports_text_ranges()` is already true before the first
1957    /// keystroke (the change-diff's *old* node must also support ranges
1958    /// for the notification to fire). Target the caret/selection at the
1959    /// returned `NodeId` via [`set_text_selection_to`](Self::set_text_selection_to).
1960    pub fn push_text_run_child_on_self(
1961        &mut self,
1962        element_id: u64,
1963        value: String,
1964        character_lengths: Vec<u8>,
1965        word_starts: Option<Vec<u8>>,
1966    ) -> NodeId {
1967        let Some(owner) = self.owner else {
1968            debug_assert!(
1969                false,
1970                "push_text_run_child_on_self called on a builder with no owner — \
1971                 widgets must only call this from Widget::accessibility"
1972            );
1973            return NodeId(0);
1974        };
1975        let node_id = synthetic_node_id(owner, element_id, SyntheticKind::TextRun);
1976        let mut node = Node::new(Role::TextRun);
1977        node.set_value(value);
1978        node.set_character_lengths(character_lengths);
1979        if let Some(ws) = word_starts {
1980            node.set_word_starts(ws);
1981        }
1982        self.children_collected.push((node_id, node));
1983        self.inner.push_child(node_id);
1984        node_id
1985    }
1986
1987    /// Declare a text selection that references TextRun children
1988    /// previously emitted via `push_text_run_child`. Both the
1989    /// anchor and the focus are expressed as
1990    /// `(NodeId, character_index)` pairs where the character index
1991    /// is an index into the target TextRun's `character_lengths`
1992    /// (NOT a document-absolute offset — per AccessKit's contract).
1993    pub fn set_text_selection_to(&mut self, anchor: (NodeId, usize), focus: (NodeId, usize)) {
1994        self.pending_explicit_selection = Some((
1995            TextPosition {
1996                node: anchor.0,
1997                character_index: anchor.1,
1998            },
1999            TextPosition {
2000                node: focus.0,
2001                character_index: focus.1,
2002            },
2003        ));
2004    }
2005}
2006
2007impl Default for AccessNodeBuilder {
2008    fn default() -> Self {
2009        Self::new()
2010    }
2011}
2012
2013/// Convert a WidgetId to an AccessKit NodeId.
2014///
2015/// This is the id the tree gives the widget's node, and the one every update
2016/// [`crate::WidgetTree::sync_accessibility`] returns carries. A platform
2017/// adapter can hold another for the same node: one that left the tree a
2018/// reader sees and came back is handed a new id on its way out, see
2019/// [`crate::WidgetTree::deliver_accessibility`].
2020pub fn widget_id_to_node_id(id: WidgetId) -> NodeId {
2021    use slotmap::Key;
2022    let key_data = id.data();
2023    let raw = key_data.as_ffi();
2024    NodeId(raw)
2025}
2026
2027/// Convert an AccessKit NodeId back to a WidgetId. Returns `None`
2028/// for synthetic NodeIds (widget-emitted child nodes like TextRuns);
2029/// callers that need to route an `ActionRequest` targeting a
2030/// synthetic NodeId must consult `WidgetTree::synthetic_parent_map`
2031/// to find the owning widget.
2032pub fn node_id_to_widget_id_maybe(node_id: NodeId) -> Option<WidgetId> {
2033    if is_synthetic(node_id) {
2034        return None;
2035    }
2036    use slotmap::KeyData;
2037    let key_data = KeyData::from_ffi(node_id.0);
2038    Some(key_data.into())
2039}
2040
2041/// Legacy infallible converter kept for existing call sites that
2042/// never encounter synthetic NodeIds. New code should prefer
2043/// [`node_id_to_widget_id_maybe`]. Panics in debug for synthetic
2044/// ids to catch misrouted calls early.
2045pub fn node_id_to_widget_id(node_id: NodeId) -> WidgetId {
2046    debug_assert!(
2047        !is_synthetic(node_id),
2048        "node_id_to_widget_id called on synthetic NodeId — use node_id_to_widget_id_maybe"
2049    );
2050    use slotmap::KeyData;
2051    let key_data = KeyData::from_ffi(node_id.0);
2052    key_data.into()
2053}
2054
2055/// The special root node ID for the accessibility tree.
2056pub fn root_node_id() -> NodeId {
2057    NodeId(0)
2058}
2059
2060/// Query result for accessibility information about a widget.
2061#[derive(Debug)]
2062pub struct AccessibilityInfo {
2063    role: Role,
2064    name: Option<String>,
2065    actions: Vec<Action>,
2066    toggled: Option<bool>,
2067    expanded: Option<bool>,
2068    selected: Option<bool>,
2069    disabled: bool,
2070    hidden: bool,
2071    published: bool,
2072    value: Option<String>,
2073    numeric_value: Option<f64>,
2074    min_numeric_value: Option<f64>,
2075    max_numeric_value: Option<f64>,
2076    custom_actions: Vec<String>,
2077}
2078
2079impl AccessibilityInfo {
2080    pub fn new(role: Role, name: Option<String>, actions: Vec<Action>) -> Self {
2081        Self {
2082            role,
2083            name,
2084            actions,
2085            toggled: None,
2086            expanded: None,
2087            selected: None,
2088            disabled: false,
2089            hidden: false,
2090            published: true,
2091            value: None,
2092            numeric_value: None,
2093            min_numeric_value: None,
2094            max_numeric_value: None,
2095            custom_actions: Vec::new(),
2096        }
2097    }
2098
2099    pub fn with_value(mut self, value: impl Into<String>) -> Self {
2100        self.value = Some(value.into());
2101        self
2102    }
2103
2104    pub fn with_numeric_value(mut self, value: f64) -> Self {
2105        self.numeric_value = Some(value);
2106        self
2107    }
2108
2109    /// Set the numeric range; either bound may be absent.
2110    pub fn with_numeric_range(mut self, min: Option<f64>, max: Option<f64>) -> Self {
2111        self.min_numeric_value = min;
2112        self.max_numeric_value = max;
2113        self
2114    }
2115
2116    /// Set the custom-action labels, in declaration order.
2117    pub fn with_custom_actions(mut self, labels: Vec<String>) -> Self {
2118        self.custom_actions = labels;
2119        self
2120    }
2121
2122    pub fn with_toggled(mut self, toggled: bool) -> Self {
2123        self.toggled = Some(toggled);
2124        self
2125    }
2126
2127    pub fn with_expanded(mut self, expanded: bool) -> Self {
2128        self.expanded = Some(expanded);
2129        self
2130    }
2131
2132    pub fn with_selected(mut self, selected: bool) -> Self {
2133        self.selected = Some(selected);
2134        self
2135    }
2136
2137    pub fn with_disabled(mut self, disabled: bool) -> Self {
2138        self.disabled = disabled;
2139        self
2140    }
2141
2142    pub fn with_hidden(mut self, hidden: bool) -> Self {
2143        self.hidden = hidden;
2144        self
2145    }
2146
2147    /// Record whether the node is in the published AT tree; see
2148    /// [`published`](Self::published). A node is published unless set
2149    /// otherwise.
2150    pub fn with_published(mut self, published: bool) -> Self {
2151        self.published = published;
2152        self
2153    }
2154
2155    pub fn role(&self) -> Role {
2156        self.role
2157    }
2158
2159    pub fn name(&self) -> Option<&str> {
2160        self.name.as_deref()
2161    }
2162
2163    pub fn actions(&self) -> &[Action] {
2164        &self.actions
2165    }
2166
2167    pub fn is_toggled(&self) -> bool {
2168        self.toggled.unwrap_or(false)
2169    }
2170
2171    pub fn is_expanded(&self) -> bool {
2172        self.expanded.unwrap_or(false)
2173    }
2174
2175    pub fn is_selected(&self) -> bool {
2176        self.selected.unwrap_or(false)
2177    }
2178
2179    pub fn is_disabled(&self) -> bool {
2180        self.disabled
2181    }
2182
2183    pub fn is_hidden(&self) -> bool {
2184        self.hidden
2185    }
2186
2187    /// Whether assistive technology can reach this node: `false` for a
2188    /// dormant node (a hidden `Switcher` page, a `visible_when(false)`
2189    /// branch), one under an ancestor whose subtree is excluded or merged,
2190    /// and one marked [hidden](Self::is_hidden).
2191    ///
2192    /// The other getters describe what the widget would say; this says
2193    /// whether it is being heard. A test that reads names across a tree
2194    /// filters on it.
2195    pub fn published(&self) -> bool {
2196        self.published && !self.hidden
2197    }
2198
2199    /// The node's value text (`Node::value`), if it has one.
2200    pub fn value(&self) -> Option<&str> {
2201        self.value.as_deref()
2202    }
2203
2204    /// The node's numeric value (a slider's position, a spin box's number).
2205    pub fn numeric_value(&self) -> Option<f64> {
2206        self.numeric_value
2207    }
2208
2209    /// The lower bound of the numeric range, if the node declares one.
2210    pub fn min_numeric_value(&self) -> Option<f64> {
2211        self.min_numeric_value
2212    }
2213
2214    /// The upper bound of the numeric range, if the node declares one.
2215    pub fn max_numeric_value(&self) -> Option<f64> {
2216        self.max_numeric_value
2217    }
2218
2219    /// The labels of the node's custom actions, in declaration order (the
2220    /// widget's own first, then any `access_custom_action` overrides).
2221    pub fn custom_actions(&self) -> &[String] {
2222        &self.custom_actions
2223    }
2224}
2225
2226#[cfg(test)]
2227mod tests {
2228    use super::*;
2229
2230    fn fake_widget(id: u64) -> WidgetId {
2231        slotmap::KeyData::from_ffi(id).into()
2232    }
2233
2234    #[test]
2235    fn widget_derived_node_id_has_bit_63_clear() {
2236        // A freshly-minted slotmap key (version 1, index 0) encodes
2237        // to a u64 with bit 63 clear. The top-bit namespace split
2238        // (synthetic NodeIds set bit 63, widget-derived NodeIds clear
2239        // it) only works if widget-derived NodeIds stay below bit 63.
2240        let wid = fake_widget(1);
2241        let nid = widget_id_to_node_id(wid);
2242        assert_eq!(
2243            nid.0 & SYNTHETIC_BIT,
2244            0,
2245            "widget NodeId must have bit 63 clear"
2246        );
2247        assert!(!is_synthetic(nid));
2248    }
2249
2250    #[test]
2251    fn synthetic_node_id_has_bit_63_set() {
2252        let wid = fake_widget(42);
2253        let nid = synthetic_node_id(wid, 17, SyntheticKind::TextRun);
2254        assert_eq!(nid.0 & SYNTHETIC_BIT, SYNTHETIC_BIT);
2255        assert!(is_synthetic(nid));
2256    }
2257
2258    #[test]
2259    fn link_runs_on_line_chains_runs_both_ways() {
2260        let mut b = AccessNodeBuilder::for_widget(fake_widget(1));
2261        let para = b.push_paragraph_child(1);
2262        let run = |b: &mut AccessNodeBuilder, off: usize| {
2263            b.push_text_run_child(
2264                para,
2265                10,
2266                off,
2267                "abc".to_string(),
2268                vec![1, 1, 1],
2269                None,
2270                None,
2271                None,
2272                TextRunAttributes::default(),
2273            )
2274        };
2275        let (r0, r1, r2) = (run(&mut b, 0), run(&mut b, 3), run(&mut b, 6));
2276        b.link_runs_on_line(&[r0, r1, r2]);
2277
2278        let (_id, _n, children, _local) = b.build(fake_widget(1));
2279        let node = |id| {
2280            children
2281                .iter()
2282                .find(|(i, _)| *i == id)
2283                .map(|(_, n)| n)
2284                .unwrap()
2285        };
2286        // First run: forward only. Middle: both. Last: back only.
2287        assert_eq!(node(r0).previous_on_line(), None);
2288        assert_eq!(node(r0).next_on_line(), Some(r1));
2289        assert_eq!(node(r1).previous_on_line(), Some(r0));
2290        assert_eq!(node(r1).next_on_line(), Some(r2));
2291        assert_eq!(node(r2).previous_on_line(), Some(r1));
2292        assert_eq!(node(r2).next_on_line(), None);
2293    }
2294
2295    /// A chunk at a non-zero offset in one element must not collide with a
2296    /// whole run in another element, even when the two element ids differ by
2297    /// exactly the low-byte XOR of the chunk offset — the aliasing the old
2298    /// `element_id ^ (offset << 32)` mix allowed.
2299    #[test]
2300    fn a_chunk_offset_does_not_alias_another_elements_run() {
2301        let mut b = AccessNodeBuilder::for_widget(fake_widget(1));
2302        let para = b.push_paragraph_child(1);
2303        // `synth_element_id` encodes the block id in bits 32-61.
2304        let elem_a: u64 = 0xABCD_u64 << 32;
2305        let elem_b: u64 = (0xABCD_u64 ^ 255) << 32;
2306        let run = |b: &mut AccessNodeBuilder, elem: u64, off: usize| {
2307            b.push_text_run_child(
2308                para,
2309                elem,
2310                off,
2311                "x".to_string(),
2312                vec![1],
2313                None,
2314                None,
2315                None,
2316                TextRunAttributes::default(),
2317            )
2318        };
2319        let a_chunk = run(&mut b, elem_a, 255); // offset-255 chunk in block A
2320        let b_whole = run(&mut b, elem_b, 0); // whole run in block B = A ^ 255
2321        assert_ne!(
2322            a_chunk, b_whole,
2323            "a chunk offset must not alias another block's run NodeId"
2324        );
2325    }
2326
2327    #[test]
2328    fn set_child_position_in_set_numbers_a_paragraph() {
2329        let mut b = AccessNodeBuilder::for_widget(fake_widget(1));
2330        let para = b.push_paragraph_child(5);
2331        assert!(b.set_child_position_in_set(para, 42, 200));
2332        assert!(
2333            !b.set_child_position_in_set(NodeId(999), 1, 1),
2334            "an unknown child is not found"
2335        );
2336
2337        let (_id, own, children, _local) = b.build(fake_widget(1));
2338        let p = children
2339            .iter()
2340            .find(|(i, _)| *i == para)
2341            .map(|(_, n)| n)
2342            .unwrap();
2343        // The caller says "line 42", the ARIA convention. AccessKit stores the
2344        // zero-based 41, and the Windows and AT-SPI adapters add the 1 back.
2345        assert_eq!(p.position_in_set(), Some(41));
2346        // The set size belongs on the container, which here is the widget's own
2347        // node: `size_of_set_from_container` walks up from the item's parent,
2348        // so a size written on the paragraph itself is read by no adapter.
2349        assert_eq!(p.size_of_set(), None);
2350        assert_eq!(own.size_of_set(), Some(200));
2351    }
2352
2353    /// The whole point of the 1-based public surface: a caller writes the
2354    /// number a person would say, and AccessKit gets the number it expects.
2355    #[test]
2356    fn every_aria_ordinal_is_converted_at_the_boundary() {
2357        let mut b = AccessNodeBuilder::for_widget(fake_widget(1));
2358        b.set_position_in_set(1);
2359        b.set_row_index(1);
2360        b.set_column_index(1);
2361        b.set_level(1);
2362        let (_id, n, _children, _local) = b.build(fake_widget(1));
2363        assert_eq!(n.position_in_set(), Some(0), "the first item is index 0");
2364        assert_eq!(n.row_index(), Some(0), "the header row is row 0");
2365        assert_eq!(n.column_index(), Some(0), "the leftmost column is column 0");
2366        assert_eq!(n.level(), Some(0), "a root item is level 0");
2367    }
2368
2369    /// A count has no base, so it must pass through untouched. Getting this
2370    /// wrong would turn "3 of 12" into "3 of 11".
2371    #[test]
2372    fn a_count_is_not_an_ordinal_and_is_not_converted() {
2373        let mut b = AccessNodeBuilder::for_widget(fake_widget(1));
2374        b.set_size_of_set(12);
2375        b.set_row_count(100);
2376        b.set_column_count(4);
2377        b.set_row_span(2);
2378        b.set_column_span(3);
2379        let (_id, n, _children, _local) = b.build(fake_widget(1));
2380        assert_eq!(n.size_of_set(), Some(12));
2381        assert_eq!(n.row_count(), Some(100));
2382        assert_eq!(n.column_count(), Some(4));
2383        assert_eq!(n.row_span(), Some(2));
2384        assert_eq!(n.column_span(), Some(3));
2385    }
2386
2387    /// A heading level is the same ARIA convention, and an H1 must be able to
2388    /// announce as level 1. Before the conversion the clamp floor of 1 made
2389    /// AccessKit level 0 unreachable, so no heading anywhere could.
2390    #[test]
2391    fn an_h1_is_accesskit_level_zero() {
2392        for (heading, expected) in [(1u8, 0usize), (2, 1), (6, 5)] {
2393            let mut b = AccessNodeBuilder::for_widget(fake_widget(1));
2394            let para = b.push_paragraph_child(7);
2395            assert!(b.set_paragraph_as_heading(para, heading));
2396            let (_id, _n, children, _local) = b.build(fake_widget(1));
2397            let p = children
2398                .iter()
2399                .find(|(i, _)| *i == para)
2400                .map(|(_, n)| n)
2401                .unwrap();
2402            assert_eq!(p.role(), Role::Heading);
2403            assert_eq!(p.level(), Some(expected), "h{heading}");
2404        }
2405    }
2406
2407    #[test]
2408    fn synthetic_node_id_stable_across_calls() {
2409        // Same (widget, element, kind) produces identical NodeIds —
2410        // this stability is required for screen-reader focus to survive
2411        // accessibility rebuilds.
2412        let wid = fake_widget(42);
2413        let a = synthetic_node_id(wid, 17, SyntheticKind::TextRun);
2414        let b = synthetic_node_id(wid, 17, SyntheticKind::TextRun);
2415        assert_eq!(a, b);
2416    }
2417
2418    #[test]
2419    fn synthetic_node_id_differs_by_kind() {
2420        let wid = fake_widget(42);
2421        let p = synthetic_node_id(wid, 17, SyntheticKind::Paragraph);
2422        let r = synthetic_node_id(wid, 17, SyntheticKind::TextRun);
2423        assert_ne!(
2424            p, r,
2425            "paragraph and text-run kinds must produce distinct NodeIds"
2426        );
2427    }
2428
2429    #[test]
2430    fn synthetic_node_id_differs_by_element() {
2431        let wid = fake_widget(42);
2432        let a = synthetic_node_id(wid, 1, SyntheticKind::TextRun);
2433        let b = synthetic_node_id(wid, 2, SyntheticKind::TextRun);
2434        assert_ne!(a, b);
2435    }
2436
2437    #[test]
2438    fn node_id_to_widget_id_maybe_returns_none_for_synthetic() {
2439        let wid = fake_widget(42);
2440        let syn = synthetic_node_id(wid, 17, SyntheticKind::TextRun);
2441        assert!(node_id_to_widget_id_maybe(syn).is_none());
2442    }
2443
2444    #[test]
2445    fn node_id_to_widget_id_maybe_round_trips_widget_ids() {
2446        let wid = fake_widget(99);
2447        let nid = widget_id_to_node_id(wid);
2448        let back = node_id_to_widget_id_maybe(nid).unwrap();
2449        assert_eq!(wid, back);
2450    }
2451
2452    #[test]
2453    fn push_paragraph_child_and_text_run_child_emit_synthetic_nodes() {
2454        let owner = fake_widget(7);
2455        let mut builder = AccessNodeBuilder::for_widget(owner);
2456        builder.set_role(Role::MultilineTextInput);
2457
2458        let para = builder.push_paragraph_child(100);
2459        let run = builder.push_text_run_child(
2460            para,
2461            200,
2462            0,
2463            "hello".to_string(),
2464            vec![1, 1, 1, 1, 1],
2465            Some(vec![0]),
2466            None,
2467            None,
2468            TextRunAttributes::default(),
2469        );
2470        assert!(is_synthetic(para));
2471        assert!(is_synthetic(run));
2472
2473        let (_nid, _node, children, _local) = builder.build(owner);
2474        // Two emitted children: paragraph + text run.
2475        assert_eq!(children.len(), 2);
2476        assert!(children.iter().any(|(id, _)| *id == para));
2477        assert!(children.iter().any(|(id, _)| *id == run));
2478    }
2479
2480    #[test]
2481    fn text_run_attributes_reach_at_node() {
2482        // Audit G7 / EN 301 549 11.5.2.9: bold / italic / underline /
2483        // strikethrough formatting on a run is exposed on its TextRun node.
2484        let owner = fake_widget(9);
2485        let mut builder = AccessNodeBuilder::for_widget(owner);
2486        builder.set_role(Role::MultilineTextInput);
2487        let para = builder.push_paragraph_child(1);
2488        let run = builder.push_text_run_child(
2489            para,
2490            2,
2491            0,
2492            "ab".to_string(),
2493            vec![1, 1],
2494            None,
2495            None,
2496            None,
2497            TextRunAttributes {
2498                bold: true,
2499                italic: true,
2500                underline: true,
2501                strikethrough: true,
2502                ..Default::default()
2503            },
2504        );
2505        let (_nid, _node, children, _local) = builder.build(owner);
2506        let (_, run_node) = children
2507            .iter()
2508            .find(|(id, _)| *id == run)
2509            .expect("run node");
2510        assert_eq!(
2511            run_node.font_weight(),
2512            Some(700.0),
2513            "bold folds to font weight 700"
2514        );
2515        assert!(run_node.is_italic(), "italic flag set");
2516        assert!(run_node.underline().is_some(), "underline decoration set");
2517        assert!(
2518            run_node.strikethrough().is_some(),
2519            "strikethrough decoration set"
2520        );
2521
2522        // An explicit numeric weight wins over the bold flag.
2523        let owner2 = fake_widget(10);
2524        let mut b2 = AccessNodeBuilder::for_widget(owner2);
2525        b2.set_role(Role::MultilineTextInput);
2526        let p2 = b2.push_paragraph_child(1);
2527        let r2 = b2.push_text_run_child(
2528            p2,
2529            2,
2530            0,
2531            "x".to_string(),
2532            vec![1],
2533            None,
2534            None,
2535            None,
2536            TextRunAttributes {
2537                bold: true,
2538                font_weight: Some(300),
2539                ..Default::default()
2540            },
2541        );
2542        let (_, _, kids2, _local) = b2.build(owner2);
2543        let (_, r2n) = kids2.iter().find(|(id, _)| *id == r2).expect("run2 node");
2544        assert_eq!(
2545            r2n.font_weight(),
2546            Some(300.0),
2547            "explicit weight wins over bold"
2548        );
2549    }
2550
2551    #[test]
2552    fn set_text_selection_to_wins_over_self_selection() {
2553        let owner = fake_widget(3);
2554        let mut builder = AccessNodeBuilder::for_widget(owner);
2555        builder.set_role(Role::MultilineTextInput);
2556        // Emit a paragraph + run so set_text_selection_to has a
2557        // real synthetic NodeId to target.
2558        let para = builder.push_paragraph_child(1);
2559        let run = builder.push_text_run_child(
2560            para,
2561            2,
2562            0,
2563            "ab".to_string(),
2564            vec![1, 1],
2565            None,
2566            None,
2567            None,
2568            TextRunAttributes::default(),
2569        );
2570        // Both a self-targeted AND an explicit selection are
2571        // staged — the explicit one must win.
2572        builder.set_text_selection_on_self(0, 0);
2573        builder.set_text_selection_to((run, 0), (run, 2));
2574        let (_nid, node, _children, _local) = builder.build(owner);
2575        let sel = node.text_selection().expect("text selection set");
2576        assert_eq!(sel.focus.node, run);
2577        assert_eq!(sel.focus.character_index, 2);
2578    }
2579
2580    /// A `Status` holding its text only as a value has no name on any
2581    /// platform, so it announces nothing: the adapters read a value as the
2582    /// name for a `Role::Label` alone.
2583    #[test]
2584    fn a_status_holding_its_text_as_a_value_announces_no_name() {
2585        let mut status = Node::new(Role::Status);
2586        status.set_value("Enregistré".to_string());
2587        assert_eq!(announced_text(&status), None);
2588
2589        status.set_label("Prêt".to_string());
2590        assert_eq!(announced_text(&status), Some("Prêt"));
2591    }
2592
2593    /// A `Role::Label` is named by its value, and by nothing else.
2594    #[test]
2595    fn a_label_is_named_by_its_value_alone() {
2596        let mut label = Node::new(Role::Label);
2597        label.set_label("Titre".to_string());
2598        assert_eq!(announced_text(&label), None);
2599
2600        label.set_value("Enregistré".to_string());
2601        assert_eq!(announced_text(&label), Some("Enregistré"));
2602    }
2603}