code.ts

//
// Bingo
// So far only one method: `shuffleSelection`
//

// Swaps positions randomly of the selected node's children's children
//   assumes cells are grouped into rows or columns on the bingo board
// To use, select the frame that contains rows/cols, e.g. 
//   Bingo <Selection>
//     Row
//       Cell 1
//       Cell 2...
// If you name a node as "FREE" it'll be put in the middle
//   assumes those rows/columns are in order (to support freeNode)
const shuffleChildren = (freeNodeName: string) => {
  const children = [];
  const rows = [];
  const wrap = [];

  // Idk why I have to push a single selection into an array first
  // But typescript cries if I don't do this
  figma.currentPage.selection.forEach(n => {
    wrap.push(n);
  });

  let freeNode = null;
  wrap.forEach(w => {
    w.children.forEach(r => {
      r.children.forEach(c => {
        rows.push(r);
        if (c.name !== freeNodeName) {
          children.push(c)
        } else {
          freeNode = c;
        }
      });
    });
  });

  const newOrder = shuffle(children.slice());
  if (freeNode !== null) {
    newOrder.splice(Math.floor(newOrder.length/2), 0, freeNode);
  }

  rows.forEach((r, i) => {
    r.appendChild(newOrder[i]);
  });
}
shuffleChildren("FREE");
figma.closePlugin()


//----------------------------------------------------------------------
// Helpers
//----------------------------------------------------------------------

function shuffle(array) {
  var currentIndex = array.length, temporaryValue, randomIndex;

  // While there remain elements to shuffle...
  while (0 !== currentIndex) {

    // Pick a remaining element...
    randomIndex = Math.floor(Math.random() * currentIndex);
    currentIndex -= 1;

    // And swap it with the current element.
    temporaryValue = array[currentIndex];
    array[currentIndex] = array[randomIndex];
    array[randomIndex] = temporaryValue;
  }

  return array;
}