var Promise = require('bluebird');
var inherits = require('inherits');
var extend = require('xtend/mutable');

function FantasyPromise() {
  return new (Promise.bind.apply(Promise, [this].concat([].slice.call(arguments))));
}

inherits(FantasyPromise, Promise);
extend(FantasyPromis, Promise);

FantasyPromise.prototype.chain = function(fn) {
  var that = this;
  return new FantasyPromise(function(resolve, reject) {
    that.then(function(v) {
      return fn(v).then(resolve);
    }).catch(reject);
  });
};

FantasyPromise.of = Promise.resolve;

module.exports = FantasyPromise;