Module palette 

Surface-neutral command palette, focus model, accessibility metadata, and diagnostics presentation (VIEW4.06).

These are the interaction semantics SHARED by every view surface – the TUI (the sim-view-tty consumer) and the Web UI alike. The module is deliberately surface-neutral: it emits ordinary Scene values and Intent values and reads them back, but it never spells ANSI, DOM, or ARIA. A terminal renderer turns a focus annotation into a highlight; a browser turns the same annotation into a :focus ring and the A11y record into ARIA attributes. The core Scene carries only open metadata, so neither surface’s vocabulary leaks into the shared model.

Four facilities live here:

• a with_focus/focused_id/move_focus focus model stored as a focus metadata field, not a new scene kind;
• a Command palette: palette_scene renders a filtered, deterministic overlay and palette_intent reduces a chosen command to a validated Intent;
• an A11y accessibility record attached as an open a11y map via with_a11y and read back with a11y_of;
• diagnostics_scene, which presents a rejected Draft’s diagnostics as a deterministic overlay.

Example

use sim_kernel::Symbol;
use sim_lib_view::palette::{Command, CommandKind, palette_intent, palette_scene};

let cmd = Command {
    id: Symbol::new("run"),
    label: "Run validation".to_owned(),
    kind: CommandKind::Invoke,
};
// The overlay lists the command and validates as a Scene.
let scene = palette_scene(std::slice::from_ref(&cmd), "run");
assert!(sim_lib_scene::validate_scene(&scene).is_ok());
// The chosen command reduces to a validated Intent.
let intent = palette_intent(&cmd, "main", 7).unwrap();
assert!(sim_lib_intent::validate_intent(&intent).is_ok());

Structs

A11y

An accessibility record carried as open metadata on a scene node.

Command

One palette command: a stable id, a human label, and the kind of Intent it reduces to.

Enums

CommandKind

How a Command reduces to an Intent when chosen.

FocusDir

A direction to advance focus in move_focus.

Constants

A11Y_KEY

The map key under which with_a11y stores the accessibility record.

FOCUS_KEY

The map key under which the focus model stores the focused node id.

Functions

a11y_of

Reads the accessibility record attached by with_a11y, if present and well-formed.

diagnostics_scene

Presents a Draft’s diagnostics as a deterministic scene/overlay.

filter_commands

Selects the commands whose label contains filter, case-insensitively, preserving input order.

focused_id

Reads the focused node id annotated by with_focus, if any.

move_focus

Advances focus deterministically through ids_in_order, wrapping at the ends, and returns the re-annotated scene.

palette_intent

Reduces a chosen Command to its matching validated Intent for pane at tick.

palette_scene

Builds a scene/overlay listing the commands matching filter.

with_a11y

Attaches an a11y metadata map (role/label/description/urgency) to node.

with_focus

Annotates scene with focused_id as open focus metadata.