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@public-ui/components

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Contains all web components that belong to KoliBri - The accessible HTML-Standard.

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/*! * KoliBri - The accessible HTML-Standard */ import { hex } from "wcag-contrast"; import rgba from "color-rgba"; import rgbaConvert from "rgba-convert"; export const getContrastYIQ = (r, g, b) => { const yiq = (r * 299 + g * 587 + b * 114) / 1000; return yiq >= 128 ? -1 : 1; }; export const calcColorContrast = (baseColor, contrastColor, ratio, dir = 1) => { const color = [ Math.max(Math.min(Math.round(contrastColor[0] + dir * Math.max(1, contrastColor[0] / 100)), 255), 0), Math.max(Math.min(Math.round(contrastColor[1] + dir * Math.max(1, contrastColor[1] / 100)), 255), 0), Math.max(Math.min(Math.round(contrastColor[2] + dir * Math.max(1, contrastColor[2] / 100)), 255), 0), ]; const contrast = hex(rgbaConvert.hex(`rgba(${baseColor.join(',')},1)`), rgbaConvert.hex(`rgba(${color.join(',')},1)`)); const summe = color[0] + color[1] + color[2]; if (summe === 0 || summe === 765 || contrast > ratio) { return { background: baseColor, foreground: color, contrast, }; } else { return calcColorContrast(baseColor, color, ratio, dir); } }; const cache = new Map(); export const getColorContrast = (baseColor, contrastColor, ratio, dir = 1) => { if (cache.has(baseColor)) { return cache.get(baseColor); } const color = calcColorContrast(baseColor, contrastColor, ratio, dir); cache.set(baseColor, color); return color; }; export const createContrastColorPair = (color, contrastRatio = 7) => { let baseColor = [0, 0, 0, 1]; let contrastColor = [255, 255, 255, 1]; if (typeof color === 'string') { baseColor = rgba(color); contrastColor = baseColor; } else if (typeof color === 'object' && color !== null && typeof color.background === 'string' && typeof color.foreground === 'string') { baseColor = rgba(color.background); if (typeof color.foreground === 'string') { contrastColor = rgba(color.foreground); } else { contrastColor = baseColor; } } const yiq = getContrastYIQ(baseColor[0], baseColor[1], baseColor[2]); const colorContrast = getColorContrast([baseColor[0], baseColor[1], baseColor[2]], [contrastColor[0], contrastColor[1], contrastColor[2]], contrastRatio, yiq); contrastColor = [...colorContrast.foreground, 1]; return { background: rgbaConvert.hex(`rgba(${baseColor.join(',')})`), foreground: rgbaConvert.hex(`rgba(${contrastColor.join(',')})`), contrast: colorContrast.contrast, }; }; //# sourceMappingURL=contrast.js.map