Sugiyama algorithm: minimizing crossings, naive approach

minimizeCrossings.js

var minimizeCrossingsArisingFromColumnAndRows = function(grid, columnIndex, rowIndex1, rowIndex2) {
  var originalNode1 = grid[columnIndex][rowIndex1];
  var originalNode2 = grid[columnIndex][rowIndex2];
  var nextColumn = grid[columnIndex + 1];

  for (var nextNode1Index = 0; nextNode1Index < originalNode1.nextNodes.length; nextNode1Index++) {
    var nextNode1 = originalNode1.nextNodes[nextNode1Index];
    var nextNode1Row = nextColumn.indexOf(nextNode1);

    for (var nextNode2Index = 0; nextNode2Index < originalNode2.nextNodes.length; nextNode2Index++) {
      var nextNode2 = originalNode2.nextNodes[nextNode2Index];
      var nextNode2Row = nextColumn.indexOf(nextNode2);

      if (nextNode1Row > nextNode2Row) {
        nextColumn.splice(nextNode1Row, 1, nextNode2);
        nextColumn.splice(nextNode2Row, 1, nextNode1);
        // switch variables too (no temporary variables)
        nextNode1Row = nextNode2Row + (nextNode2Row = nextNode1Row, 0);
      }
    }
  }
};

var minimizeCrossingsArisingFromColumn = function(grid, columnIndex) {
  for (var rowIndex = 0; rowIndex < grid[columnIndex].length; rowIndex++) {
    for (var secondNodeIndex = rowIndex + 1; secondNodeIndex < grid[columnIndex].length; secondNodeIndex++) {
      minimizeCrossingsArisingFromColumnAndRows(grid, columnIndex, rowIndex, secondNodeIndex);
    }
  }
};

sugiyamaService.minimizeCrossings = function(grid) {
  for (var columnIndex = 0; columnIndex < grid.length; columnIndex++) {
    minimizeCrossingsArisingFromColumn(grid, columnIndex);
  }
};