/**
 * Enough colour maths to keep a resolved token legible: WCAG relative luminance,
 * a contrast ratio, and the largest share of a hue that still clears a threshold
 * against the surface it is painted on.
 *
 * Colour parsing is injected rather than implemented here. Provider slots resolve
 * to `oklch()` under DaisyUI 5, so an oklch-to-sRGB implementation in this file
 * would be a second opinion about colours the browser has already decided;
 * `createCanvasColorMeasure` asks the browser instead.
 */
export interface Srgb {
    r: number;
    g: number;
    b: number;
    /** 0..1 */
    a: number;
}
/** Resolves any CSS colour syntax to 8-bit sRGB, or `null` if not a colour. */
export type ColorMeasure = (value: string) => Srgb | null;
/** WCAG 2.2 1.4.3 for text. */
export declare const LEGIBLE_TEXT_MINIMUM = 4.5;
/** WCAG 2.2 1.4.11 for component boundaries, states and graphical objects. */
export declare const LEGIBLE_NON_TEXT_MINIMUM = 3;
/**
 * The hue share used when contrast cannot be measured. 30% is the largest 5%
 * step that clears 4.5:1 for every success, error and warning slot across
 * DaisyUI's 28 shipped themes — measured across all 84 combinations rather than
 * picked. It is deliberately pessimistic: a theme whose slot needed no
 * correction at all still gets pulled most of the way to the text colour.
 */
export declare const UNMEASURED_HUE_WEIGHT = 30;
/**
 * The same pessimistic fallback for a 3:1 target: 35% is the largest 5% step
 * that clears 3:1 for `--color-base-300` and `--color-neutral` in all 28 themes.
 */
export declare const UNMEASURED_NON_TEXT_HUE_WEIGHT = 35;
/** WCAG relative luminance. Alpha is ignored; composite before calling. */
export declare function relativeLuminance(color: Srgb): number;
export declare function contrastRatio(foreground: Srgb, background: Srgb): number;
export declare function mixTowards(hue: string, target: string, hueWeight: number): string;
/**
 * Resolves any CSS colour the browser understands to 8-bit sRGB by painting one
 * pixel and reading it back, so `oklch()` and `color-mix()` need no parser here.
 *
 * Returns `null` where there is no canvas to paint on — a server render, or a
 * DOM shim in tests — which callers treat as "contrast is unmeasurable" rather
 * than as an error.
 */
export declare function createCanvasColorMeasure(): ColorMeasure | null;
/**
 * The given hue if it already clears `minimum` against `background`, otherwise
 * the largest share of it that does, mixed toward `text`.
 *
 * Mixing toward the theme's own text colour rather than toward black or white
 * uses the theme's own guarantee: `text` is what that theme chose to be readable
 * on that surface, in a light theme and a dark one alike. Stepping down from the
 * top keeps as much hue as the threshold allows, so a slot that was already fine
 * comes back untouched and a slot that was invisible loses only what it must.
 */
export declare function legibleColorAgainst(args: {
    hue?: string;
    text?: string;
    background?: string;
    measure?: ColorMeasure | null;
    minimum?: number;
    unmeasuredHueWeight?: number;
}): string | undefined;
/**
 * A state fill behind text that keeps its ink: the given fill if it already
 * clears `minimum` against `background`, otherwise the largest share of it,
 * mixed toward `text`, that does -- but never past the share where `text` on
 * the fill drops under `textMinimum`.
 *
 * The two pairs trade off. Moving the fill toward the ink separates it from the
 * page and brings it closer to the ink, so where text on the page is under
 * `minimum x textMinimum` no fill clears both, and the text wins: an unreadable
 * hover is worse than a faint one. It steps by 1% rather than 5% because the
 * window between the two floors is narrow; 5% steps overshoot it in `dark`,
 * `black` and `dracula`.
 *
 * Unmeasured, the fill comes back verbatim. No fixed share holds the text floor
 * across DaisyUI's shipped themes -- 90% already leaves `valentine` at 4.16:1 --
 * so the pessimistic answer here is no correction at all.
 */
export declare function legibleStateFillAgainst(args: {
    fill?: string;
    text?: string;
    background?: string;
    measure?: ColorMeasure | null;
    minimum?: number;
    textMinimum?: number;
}): string | undefined;