tui-lib/ui/presentation/Label.js

import {DisplayElement} from 'tui-lib/ui/primitives'

import * as ansi from 'tui-lib/util/ansi'

export default class Label extends DisplayElement {
  // A simple text display. Automatically adjusts size to fit text.
  //
  // Supports formatted text in two ways:
  // 1) Modify the textAttributes to be an array containing the ANSI numerical
  //    codes for any wanted attributes, and/or
  // 2) Supply full ANSI escape codes within the text itself. (The reset
  //    attributes code, ESC[0m, will be processed to reset to the provided
  //    values in textAttributes.
  //
  // Subclasses overriding the writeTextTo function should be sure to call
  // processFormatting before actually writing text.

  constructor(text = '') {
    super()

    this.text = text
    this.textAttributes = []
  }

  fixLayout() {
    this.w = ansi.measureColumns(this.text)
  }

  drawTo(writable) {
    if (this.textAttributes.length) {
      writable.write(ansi.setAttributes(this.textAttributes))
    }

    this.writeTextTo(writable)

    if (this.textAttributes.length) {
      writable.write(ansi.resetAttributes())
    }

    super.drawTo(writable)
  }

  writeTextTo(writable) {
    writable.write(ansi.moveCursor(this.absTop, this.absLeft))
    writable.write(this.processFormatting(this.text))
  }

  processFormatting(text) {
    return text.replace(new RegExp(ansi.ESC + '\\[0m', 'g'),
      ansi.setAttributes([ansi.A_RESET, ...this.textAttributes]))
  }

  set text(newText) {
    const ret = this.setDep('text', newText)
    this.fixLayout()
    return ret
  }

  get text() {
    return this.getDep('text')
  }

  // Kinda bad, but works as long as you're overwriting the array instead of
  // mutating it.
  set textAttributes(val) { return this.setDep('textAttributes', val) }
  get textAttributes() { return this.getDep('textAttributes') }
}