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'use strict';
/* eslint-disable no-mixed-operators */
module.exports = (red, green, blue, alpha) => {
const isPercent = (red + (alpha || '')).toString().includes('%');
if (typeof red === 'string') {
[red, green, blue, alpha] = red.match(/(0?\.?\d{1,3})%?\b/g).map(Number);
} else if (alpha !== undefined) {
alpha = parseFloat(alpha);
}
if (typeof red !== 'number' ||
typeof green !== 'number' ||
typeof blue !== 'number' ||
red > 255 ||
green > 255 ||
blue > 255
) {
throw new TypeError('Expected three numbers below 256');
}
if (typeof alpha === 'number') {
if (!isPercent && alpha >= 0 && alpha <= 1) {
alpha = Math.round(255 * alpha);
} else if (isPercent && alpha >= 0 && alpha <= 100) {
alpha = Math.round(255 * alpha / 100);
} else {
throw new TypeError(`Expected alpha value (${alpha}) as a fraction or percentage`);
}
alpha = (alpha | 1 << 8).toString(16).slice(1);
} else {
alpha = '';
}
return ((blue | green << 8 | red << 16) | 1 << 24).toString(16).slice(1) + alpha;
};
/* eslint-enable no-mixed-operators */
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