Method performEncode

src/Encoder/BaudotCode.js:168–213

* Performs encode on given content. * @protected * @param {Chain} content * @return {number[]|string|Uint8Array|Chain|Promise} Encoded content

(content)

   * @return {number[]|string|Uint8Array|Chain|Promise} Encoded content
   */
  performEncode (content) {
    // Retrieve character set
    const variant = this.getSettingValue('variant')
    const characterSet = this.getVariantCharacterSet(variant)
    const switchToFigures = characterSet.indexOf('FS') % 32
    const switchToLetters = characterSet.indexOf('LS') % 32

    const codePoints = content.getCodePoints()
    const m = codePoints.length

    const tape = []
    let index, codePoint
    let figureSet = false

    // Go through code points
    for (let i = 0; i < m; i++) {
      codePoint = codePoints[i]
      index = characterSet.indexOf(codePoint)

      // If character was not found try to map the uppercase character
      if (index === -1 && codePoint >= 97 && codePoint <= 122) {
        index = characterSet.indexOf(codePoint - 32)
      }

      if (index >= 0 && index < 32) {
        // This character is situated on the letter set
        // Switch to letter set
        if (figureSet) {
          tape.push(switchToLetters)
          figureSet = false
        }
        tape.push(index)
      } else if (index >= 32) {
        // This character is situated on the figure set
        // Switch to figure set
        if (!figureSet) {
          tape.push(switchToFigures)
          figureSet = true
        }
        tape.push(index - 32)
      }
    }

    // Compose byte array from 5-bit tape
    return ArrayUtil.resizeBitSizedArray(tape, 5, 8)
  }

  /**
   * Performs decode on given content.