activerecord - Rails 4 associations - modeling parties, invites, and users -

i'm attempting setup associations following scenario (from odin project):

"you hosting people dinner want build dinner party invitation site. user can create parties, invite people party, , accept invitation else's party."

i came code below have few questions:

    class user < activerecord::base         has_many :parties, foreign_key: :host_id          has_many :invitations_sent, class_name: "invitation", foreign_key: :host_id         has_many :invitations_rcvd, class_name: "invitation", foreign_key: :guest_id          has_many :guests, through: :invitations_sent         has_many :hosts, through: :invitations_rcvd     end      class invitation < activerecord::base         belongs_to :host, class_name: "user"          belongs_to :guest, class_name: "user"         belongs_to :party     end      class party < activerecord::base         belongs_to :host, class_name: "user"         has_many :invitations     end 

1. is there cleaner way implement above? seems user model doing lot wonder if it's worth splitting separate guest , host models, if they'll have same attributes/columns anyways.

2. is possible update code above expressions user.first.parties.first.invitations.create(guest_id: 2) auto-populates host_id of new invitation instance user.first's id?