@barchart/common-js/lang/formatter.js

Library of common JavaScript utilities

/**
 * Formats a number into a string for display purposes.
 *
 * @function
 * @public
 * @param {number|null|undefined} value
 * @param {number} digits
 * @param {string=} thousandsSeparator
 * @param {boolean=} useParenthesis
 */
export function numberToString(value, digits, thousandsSeparator, useParenthesis) {
	if (value === undefined || value === null || Number.isNaN(value)) {
		return '';
	}

	const applyParenthesis = value < 0 && useParenthesis === true;

	if (applyParenthesis) {
		value = 0 - value;
	}

	let returnRef = value.toFixed(digits);

	if (thousandsSeparator && !(value > -1000 && value < 1000)) {
		const length = returnRef.length;
		const negative = value < 0;

		let found = digits === 0;
		let counter = 0;

		const buffer = [];

		for (let i = (length - 1); !(i < 0); i--) {
			if (counter === 3 && !(negative && i === 0)) {
				buffer.unshift(thousandsSeparator);

				counter = 0;
			}

			const character = returnRef.charAt(i);

			buffer.unshift(character);

			if (found) {
				counter = counter + 1;
			} else if (character === '.') {
				found = true;
			}
		}

		if (applyParenthesis) {
			buffer.unshift('(');
			buffer.push(')');
		}

		returnRef = buffer.join('');
	} else if (applyParenthesis) {
		returnRef = '(' + returnRef + ')';
	}

	return returnRef;
}