Function getRGBValues

src/utils/color.ts:287–364

(input: string)

const rgbUnits = {'%': 100};

export function getRGBValues(input: string): number[] | null {
    const CHAR_CODE_0 = 48;
    const length = input.length;
    let i = 0;
    let digitsCount = 0;
    let digitSequence = false;
    let floatDigitsCount = -1;
    let delimiter = C_SPACE;
    let channel = -1;
    let result: number[] | null = null;
    while (i < length) {
        const c = input.charCodeAt(i);
        if ((c >= C_0 && c <= C_9) || c === C_DOT) {
            if (!digitSequence) {
                digitSequence = true;
                digitsCount = 0;
                floatDigitsCount = -1;
                channel++;
                if (channel === 3 && result) {
                    result[3] = 0;
                }
                if (channel > 3) {
                    return null;
                }
            }
            if (c === C_DOT) {
                if (floatDigitsCount > 0) {
                    return null;
                }
                floatDigitsCount = 0;
            } else {
                const d = c - CHAR_CODE_0;
                if (!result) {
                    result = [0, 0, 0, 1];
                }
                if (floatDigitsCount > -1) {
                    floatDigitsCount++;
                    result[channel] += d / (10 ** floatDigitsCount);
                } else {
                    digitsCount++;
                    if (digitsCount > 3) {
                        return null;
                    }
                    result[channel] = result[channel] * 10 + d;
                }
            }
        } else if (c === C_PERCENT) {
            if (channel < 0 || channel > 3 || delimiter !== C_SPACE || !result) {
                return null;
            }
            result[channel] = channel < 3 ? Math.round(result[channel] * 255 / 100) : (result[channel] / 100);
            digitSequence = false;
        } else {
            digitSequence = false;
            if (c === C_SPACE) {
                if (channel === 0) {
                    delimiter = c;
                }