sort_idented_todo_list.js

function buildNode(todo) {
  return {
    todo,
    children: [],
  };
}

function buildTree(todos) {
  const root = buildNode();

  let stack = [root];

  for (let i = 0; i < todos.length; i += 1) {
    const todo = todos[i];
    if (!stack[todo.ident]) {
      // NOTE(rstankov): THIS CASE DOESN'T WORK!
      // maybe add a lot of empty trees
      // have this into the sorting
      stack[todo.ident] = buildNode();
    }

    node = buildNode(todo);

    stack[todo.ident].children.push(node);
    stack = stack.slice(0, todo.ident + 1);
    stack[todo.ident + 1] = node;
  }

  return root;
}

function sortTree(node) {
  // TODO(rstankov): Sort three leaves based on the `isCompleted`
  return node;
}

function treeToArray(node, acc = []) {
  if (node.todo) {
    acc.push(node.todo);
  }

  return node.children.reduce((a, n) => treeToArray(n, a), acc);
}

todos = [
  {
    text: '1',
    ident: 0,
    isCompleted: false,
  },
  {
    text: '1-1',
    ident: 1,
    isCompleted: false,
  },
  {
    text: '1-1-1',
    ident: 2,
    isCompleted: false,
  },
  {
    text: '1-1-2',
    ident: 2,
    isCompleted: false,
  },
  {
    text: '1-1-----n',
    ident: 10,
    isCompleted: false,
  },
  {
    text: '1-1-3',
    ident: 2,
    isCompleted: true,
  },
  {
    text: '1-2',
    ident: 1,
    isCompleted: false,
  },
  {
    text: '2',
    ident: 0,
    isCompleted: true,
  },
  {
    text: '3',
    ident: 0,
    isCompleted: true,
  },
];

sortedArray = treeToArray(sortTree(buildTree(todos)));