// See https://www.youtube.com/watch?v=JaXo_i3ktwM
(() => {
  const randV = [2, 4, 6, 0, 9, 3, 1, 4, 0, 5];
  const randH = [7, 4, 5, 1, 8, 1, 1, 2, 2, 8];
  const tileCounts = {
    a: 9,
    b: 2,
    c: 2,
    d: 4,
    e: 12,
    f: 2,
    g: 3,
    h: 2,
    i: 9,
    j: 1,
    k: 1,
    l: 4,
    m: 2,
    n: 6,
    o: 8,
    p: 2,
    q: 1,
    r: 6,
    s: 4,
    t: 6,
    u: 4,
    v: 2,
    w: 2,
    x: 1,
    y: 2,
    z: 1,
    ' ': 2
  };
  const repeat = (item, c) => {
    const r = [];
    for (let i = 0; i < c; i++) r.push(item);
    return r;
  };
  const allTiles = [].concat(...Object.keys(tileCounts).map(l => repeat(l.toUpperCase(), tileCounts[l])));
  const grid = [];
  for (let i = 0; i < 10; i++) {
    grid.push(allTiles.slice(i * 10, i * 10 + 10));
  }
  const dupeGrid = grid => grid.map(row => row.slice());
  const transposed = grid => {
    const r = dupeGrid(grid);
    for (x = 0; x < 10; x++) {
      for (y = 0; y < 10; y++) {
        r[x][y] =  grid[y][x];
      }
    }
    return r;
  };
  const flipRow = r => r.slice().reverse();
  const rrl = (r, n) => [...r.slice(n), ...r.slice(0, n)];
  const rrr = (r, n) => flipRow(rrl(flipRow(r), n));

  const hFlipGrid = grid => grid.map(flipRow);
  const vFlipGrid = grid => transposed(hFlipGrid(transposed(grid)));
  const rgl = (grid, n) => grid.map((r, i) => rrl(r, n[i]));
  const rgr = (grid, n) => hFlipGrid(rgl(hFlipGrid(grid), n));
  const rgu = (grid, n) => transposed(rgl(transposed(grid), n));
  const rgd = (grid, n) => transposed(rgr(transposed(grid), n));

  const nRowShuffle = (grid, n) => {
    const r = dupeGrid(grid);
    for (let i = n - 1; i < 10; i += n) {
      r.unshift(r.splice(i, 1)[0]);
    }
    return r;
  }

  const nColShuffle = (grid, n) => transposed(nRowShuffle(transposed(grid), n));

  const step0 = dupeGrid(grid);
  const step1 = rgd(step0, randV);
  const step2 = rgr(step1, randH);
  const step3 = nRowShuffle(step2, 2);
  const step4 = nColShuffle(step3, 2);

  const rs = r => r.join(',').replace(/ /g, '_');
  const gs = g => '\n' + g.map(rs).join('\n') + '\n';
  console.log(gs(step0), gs(step1), gs(step2), gs(step3), gs(step4));
  //console.log(rs(step0[9]), rs(step1[9]), rs(step2[9]), rs(step3[0]), rs(step4[0]));
})();