var User = DS.Model.extend({
  messages: DS.hasMany('message', {polymorphic: true})
});

var Message = DS.Model.extend({
  user: DS.belongsTo('user'),
  body: DS.attr()
});

var Post = Message.extend({
  comments: DS.hasMany('comment'),
  
  title: DS.attr()
});

var Comment = Message.extend({
  post: DS.belongsTo('post')
});


User.FIXTURES = [{
  id: 1,
  messages: [{
    id: 1,
    type: 'post'
  }, {
    id: 2,
    type: 'comment'
  }]
}]

Post.FIXTURES = [{
  id: 1,
  title: 'My first post',
  body: 'This is interesting',
  user: 1
}];

Comment.FIXTURES = [{
  id: 2,
  body: 'I forgot to add something'
}];