/**
 * @tsplus getter Tree draw
 */
export function drawTree(tree: Tree<string>): string {
  return tree.value + drawForest("\n", tree.forest)
}

function drawForest(indentation: string, forest: Chunk<Tree<string>>): string {
  let r = ""
  const len = forest.length
  let tree: Tree<string>
  for (let i = 0; i < len; i++) {
    tree = forest.unsafeGet(i)
    const isLast = i === len - 1
    r += indentation + (isLast ? "└" : "├") + "─ " + tree.value
    r += drawForest(indentation + (len > 1 && !isLast ? "│  " : "   "), tree.forest)
  }
  return r
}