constyle/src/cjs/constyle.js

A simple and performant console styling library for Node.js

const colorCodes = {
  black: 30, red: 31, green: 32, yellow: 33, blue: 34, magenta: 35, cyan: 36, white: 37,
  gray: 90, grey: 90,
  bgBlack: 40, bgRed: 41, bgGreen: 42, bgYellow: 43, bgBlue: 44, bgMagenta: 45, bgCyan: 46, bgWhite: 47,
  bgGray: 100, bgGrey: 100,
  blackBright: 90, redBright: 91, greenBright: 92, yellowBright: 93, blueBright: 94, magentaBright: 95, cyanBright: 96, whiteBright: 97,
  bgBlackBright: 100, bgRedBright: 101, bgGreenBright: 102, bgYellowBright: 103, bgBlueBright: 104, bgMagentaBright: 105, bgCyanBright: 106, bgWhiteBright: 107,
};

const styleCodes = {
  bold: 1, dim: 2, italic: 3, underline: 4, inverse: 7, hidden: 8, strikethrough: 9,
};

class Style {
  constructor(options = {}) {
    this.options = options;
    this.openCodes = [];
    this.closeCodes = [];

    for (const key in this.options) {
      if (colorCodes[key]) {
        this.openCodes.push(`\x1b[${colorCodes[key]}m`);
        this.closeCodes.unshift(`\x1b[0m`); // Reset code
      } else if (styleCodes[key]) {
        this.openCodes.push(`\x1b[${styleCodes[key]}m`);
        this.closeCodes.unshift(`\x1b[${styleCodes[key] + 20}m`); // Corresponding close code
      }
    }
  }

  apply(text) {
    if (this.openCodes.length === 0) return text;
    return this.openCodes.join('') + text + this.closeCodes.join('');
  }
}

const style = new Proxy({}, {
  get: (target, prop) => {
    if (target[prop]) return target[prop];

    if (prop === 'reset') return (text) => `\x1b[0m${text}`;

    const styleInstance = new Style();
    const styleProxy = new Proxy(styleInstance, {
      get: (targetStyle, styleProp) => {
        if (styleProp === 'apply') return targetStyle.apply.bind(targetStyle);

        const newOptions = {...targetStyle.options};

        if (colorCodes[prop]) newOptions[prop] = true;
        else if (styleCodes[styleProp]) newOptions[styleProp] = true;

        return new Proxy(new Style(newOptions), this);
      }
    });

    target[prop] = styleProxy;
    return styleProxy;
  },
});

module.exports = style;