export default function d3Transform(chain) {
  var transforms = [];
  if (chain !== undefined) { transforms.push(chain);  }

  function push(kind, args) {
    var n = args.length;

    transforms.push(function() {
      if (kind == 'seq') {
        return args[0].apply(this, arr(arguments));
      } else {
        return kind + '(' + (n == 1 && typeof args[0] == 'function'
          ? args[0].apply(this, arr(arguments)) : args) + ')';
      }
    });
  }

  function arr(args) {
    return Array.prototype.slice.call(args);
  }

  var my = function() {
    var that = this,
      args = arr(arguments);

    return transforms.map(function(f) {
      return f.apply(that, args);
    }).join(' ');
  };

  ['translate', 'rotate', 'scale', 'matrix', 'skewX', 'skewY', 'seq'].forEach(function(t) {
    my[t] = function() {
      push(t, arr(arguments));
      return my;
    };
  });

  return my;
}