import { DesignSystem, DesignSystemResolver } from "../../design-system";
import { Swatch, SwatchResolver } from "./common";
/**
 * The named palettes of the MSFT design system
 * @deprecated - use neutralPalette and accentPalette functions instead
 */
export declare enum PaletteType {
    neutral = "neutral",
    accent = "accent"
}
/**
 * The structure of a color palette
 */
export declare type Palette = Swatch[];
/**
 * Retrieves a palette by name. This function returns a function that accepts
 * a design system, returning a palette a palette or null
 * @deprecated - use neutralPalette and accentPalette functions instead
 */
export declare function palette(paletteType: PaletteType): DesignSystemResolver<Palette>;
/**
 * A function to find the index of a swatch in a specified palette. If the color is found,
 * otherwise it will return -1
 */
export declare function findSwatchIndex(paletteResolver: Palette | DesignSystemResolver<Palette>, swatch: Swatch): DesignSystemResolver<number>;
/**
 * Returns the closest swatch in a palette to an input swatch.
 * If the input swatch cannot be converted to a color, 0 will be returned
 */
export declare function findClosestSwatchIndex(paletteResolver: Palette | DesignSystemResolver<Palette>, swatch: Swatch | DesignSystemResolver<Swatch>): DesignSystemResolver<number>;
/**
 * Determines if the design-system should be considered in "dark mode".
 * We're in dark mode if we have more contrast between #000000 and our background
 * color than #FFFFFF and our background color. That threshold can be expressed as a relative luminance
 * using the contrast formula as (1 + 0.5) / (bg + 0.05) === (bg + 0.05) / (0 + 0.05),
 * which reduces to the following, where bg is the relative luminance of the background color
 */
export declare function isDarkMode(designSystem: DesignSystem): boolean;
/**
 * Determines if the design-system should be considered in "light mode".
 */
export declare function isLightMode(designSystem: DesignSystem): boolean;
/**
 * Safely retrieves an index of a palette. The index is clamped to valid
 * array indexes so that a swatch is always returned
 */
export declare function getSwatch(index: number, colorPalette: Palette): Swatch;
export declare function getSwatch(index: DesignSystemResolver<number>, colorPalette: DesignSystemResolver<Palette>): DesignSystemResolver<Swatch>;
export declare function swatchByMode(paletteResolver: DesignSystemResolver<Palette>): (a: number | DesignSystemResolver<number>, b: number | DesignSystemResolver<number>) => DesignSystemResolver<Swatch>;
/**
 * Retrieves a swatch from an input palette, where the swatch's contrast against the reference color
 * passes an input condition. The direction to search in the palette is determined by an input condition.
 * Where to begin the search in the palette will be determined another input function that should return the starting index.
 * example: swatchByContrast(
 *              "#FFF" // compare swatches against "#FFF"
 *          )(
 *              neutralPalette // use the neutral palette from the DesignSystem - since this is a function, it will be evaluated with the DesignSystem
 *          )(
 *              () => 0 // begin searching for a swatch at the beginning of the neutral palette
 *          )(
 *              () => 1 // While searching, search in the direction toward the end of the array (-1 moves towards the beginning of the array)
 *          )(
 *              minContrastTargetFactory(4.5) // A swatch is only valid if the contrast is greater than 4.5
 *          )(
 *              designSystem // Pass the design-system. The first swatch that passes the previous condition will be returned from this function
 *          )
 */
export declare function swatchByContrast(referenceColor: string | SwatchResolver): (paletteResolver: Palette | DesignSystemResolver<Palette>) => (indexResolver: (referenceColor: string, palette: Palette, designSystem: DesignSystem) => number) => (directionResolver: (referenceIndex: number, palette: Palette, designSystem: DesignSystem) => 1 | -1) => (contrastCondition: (contrastRatio: number) => boolean) => DesignSystemResolver<Swatch>;
/**
 * Resolves the index that the contrast search algorithm should start at
 */
export declare function referenceColorInitialIndexResolver(referenceColor: string, sourcePalette: Palette, designSystem: DesignSystem): number;
export declare function findClosestBackgroundIndex(designSystem: DesignSystem): number;
export declare function minContrastTargetFactory(targetContrast: number): (instanceContrast: number) => boolean;