@technobuddha/library/wordwrap/wordwrap.mjs

A large library of useful functions

import { empty, space } from '../constants';
import splitWords from '../splitWords';
/**
 * Wrap text so that it fits within a area of fixed width
 *
 * @param input the text to wrap
 * @param options
 * @default width 75
 * @default separator \n
 * @default cut default false
 * @default trailingSpaces false
 * @returns wrapped text
 */
export function wordwrap(input, { width = 75, separator = '\n', cut = false, trailingSpaces = false } = {}) {
    if (width <= 0) {
        return input;
    }
    else if (cut) {
        let result = empty;
        // walk through each character and add separators where appropriate
        for (let i = 0; i < input.length; ++i) {
            if (i % width === 0 && i > 0)
                result += separator;
            result += input.charAt(i);
        }
        // fill the rest of the line with spaces if trailingSpaces option is true
        if (trailingSpaces)
            result += space.repeat(width - input.length % width);
        return result;
    }
    let currentColumn = 0;
    let result = empty;
    for (const word of splitWords(input)) {
        // if adding a space and the next word would cause this line to be longer than width...
        if (word.length + currentColumn > width) {
            if (trailingSpaces) {
                // fill the rest of the line with spaces if trailingSpaces option is true
                result += space.repeat(width - currentColumn);
            }
            //start new line
            result += separator;
            currentColumn = 0;
        }
        // if not at the begining of the line, add a space in front of the word
        if (currentColumn > 0) {
            result += space;
            currentColumn++;
        }
        // tack on the next word, update current column, a pop words array
        result += word;
        currentColumn += word.length;
    }
    // fill the rest of the line with spaces if trailingSpaces option is true
    if (trailingSpaces) {
        while (currentColumn++ < width)
            result += space;
    }
    return result;
}
export default wordwrap;