Class WasmTTY

packages/editor/src/runtime/wasm-tty/wasm-tty.ts:8–226

 * and communicate with one another
 */
export default class WasmTTY {
  private xterm: Terminal

  private inputCursorX: number
  private inputCursorY: number
  private inputStartCursorX: number
  private inputStartCursorY: number
  private input: string[]
  private inputSplit: string[][]

  constructor(xterm: Terminal) {
    this.xterm = xterm
    this.input = []
    this.inputSplit = []
    this.inputCursorX = 0
    this.inputCursorY = 0
  }

  async read() {
    this.input = []
    this.inputSplit = []

    const promise = new Promise((resolve) => {
      this.xterm.write('\x00', () => resolve(true))
    }).then(() => {
      const buf = this.xterm.buffer.active
      this.inputStartCursorX = buf.cursorX
      this.inputStartCursorY = buf.cursorY + buf.baseY
      this.inputCursorX = this.inputStartCursorX
      this.inputCursorY = 0
      this.xterm.focus()
    })

    return promise
  }

  reflowInput() {
    const cols = this.xterm.cols
    const lines: string[][] = []

    const inputChars = Array.from(this.input)

    const firstLine = inputChars.slice(0, cols - this.inputStartCursorX)
    lines.push(firstLine)
    let index = firstLine.length
    let lastLineFull = firstLine.length === cols - this.inputStartCursorX
    while (index < inputChars.length) {
      const line = inputChars.slice(index, index + cols)
      lines.push(line)
      index += line.length
      lastLineFull = line.length == cols
    }
    if (lastLineFull) {
      lines.push([''])
    }

    // TODO: Redraw relevant lines
    this.inputSplit = lines