ervy/lib/utils.js

const os = require('os')
const PAD = ' '
const EOL = os.EOL

const bgColors = {
  'black': '40',
  'red': '41',
  'green': '42',
  'yellow': '43',
  'blue': '44',
  'magenta': '45',
  'cyan': '46',
  'white': '47'
}

module.exports = {
  PAD,
  EOL,

  bg: (color = 'cyan', length = 1) => {
    const currentBg = bgColors[color]
    if (typeof color !== 'string' || !currentBg) {
      throw new TypeError(`Invalid backgroundColor: ${JSON.stringify(color)}`)
    }

    return '\x1b[' + currentBg + 'm' + PAD.repeat(length) + '\x1b[0m'
  },

  fg: (color = 'cyan', str) => {
    const currentBg = bgColors[color]
    if (typeof color !== 'string' || !currentBg) {
      throw new TypeError(`Invalid foregroundColor: ${JSON.stringify(color)}`)
    }

    return '\x1b[' + parseInt(bgColors[color] - 10) + 'm' + str + '\x1b[0m'
  },

  padMid: (str, width) => {
    const mid = Math.round((width - str.length) / 2)
    const length = str.length

    return length > width ? str.padEnd(width)
      : PAD.repeat(mid) + str +
      PAD.repeat(mid + ((mid * 2 + length) > width ? -1 : 0))
  },

  verifyData: (data) => {
    const length = data.length

    if (!Array.isArray(data) ||
      length === 0 ||
      !data.every(item => item.key && !Number.isNaN(item.value))
    ) {
      throw new TypeError(`Invalid data: ${JSON.stringify(data)}`)
    }
  },

  maxKeyLen: (data) => Math.max.apply(null, data.map(item => item.key.length)),
  // eslint-disable-next-line
  getOriginLen: (str) => str.replace(/\x1b\[[0-9;]*m/g, '').length,

  curForward: (step = 1) => `\x1b[${step}C`,
  curUp: (step = 1) => `\x1b[${step}A`,
  curDown: (step = 1) => `\x1b[${step}B`,
  curBack: (step = 1) => `\x1b[${step}D`
}