import type { PlatformBlocksTheme } from '../../core/theme/types';
import type { KnobAppearance, KnobVariant } from './types';
/**
 * Visual variants change the knob's *form* — stroke weights, caps, whether the body is
 * filled, whether the indicator is an arm or a dot. They deliberately do not invent their
 * own palettes: color still comes from the theme and the accent, so a variant reads the
 * same in light and dark and never fights a brand.
 *
 * Every value here is a default. The preset is merged *under* the caller's `appearance`,
 * so any single property can still be overridden without opting out of the variant.
 */
export type KnobVariantContext = {
    theme: PlatformBlocksTheme;
    /** Resolved diameter in pixels — every metric below scales off it. */
    size: number;
    /** The already-resolved highlight color for this knob. */
    accentColor: string;
    disabled: boolean;
};
/** Resolves a variant to its appearance defaults. `default` (or unset) adds nothing. */
export declare const buildKnobVariantAppearance: (variant: KnobVariant | undefined, context: KnobVariantContext) => KnobAppearance | undefined;
/**
 * Merges a caller's appearance over a variant preset, one layer deep. `false`/`null` from
 * the caller wins outright (that is how a layer gets removed), arrays replace rather than
 * concatenate, and anything the caller leaves out keeps the preset's value — so
 * `variant="retro"` plus `appearance={{ ring: { color: 'red' } }}` keeps retro's thickness.
 */
export declare const mergeKnobAppearance: (base: KnobAppearance | undefined, override: KnobAppearance | undefined) => KnobAppearance | undefined;