module ObjectCounter;

object Counter := mk@{
  count : Nat;
};

constructor create := 
  new Counter.mk@{
     count := 0
   };

method incrementBy (self: Counter) (n : Nat) := 
  out self@{count := self.count + n};
 
mutualIncrement (c1 : Counter) (c2 : Counter) : TransactionBuilder := 
  c1.incrementBy(value c2);
  c2.incrementBy(value c1);

object Kudos := mk@{
  originator : ExternalIdentity;
  owner      : ExternalIdentity;
  quantity    : Nat;
  public authorizationData : AuthorizationData;
}
logic : Bool := _ -- Here we will express the shared logic logic among all the methods.
                  -- We have a general idea but some of the details still need to be worked out.


 constructor create (originator : ExternalIdentity) (quantity : Nat) :=
   new Kudos.mk@{
         originator;
         quantity;
         owner := originator;
         authData := AuthorizationAppData.mk originator;
     };
   };
   onlyIf : Bool := _ -- extra logic specific to creation.

  method transfer (self : Kudos) (receiver : ExternalIdentity) := 
       out self{owner := receiver;
                authData := mkAuthData receiver
            };
   onlyIf : Bool := _ -- extra logic specific to transfer.

  method swap (self : Kudos) (wantOriginator : ExternalIdentity) (wantQuantity : Nat) := 
        out Kudos.mk@{
            originator := wantOriginator;
            quantity : wantQuantity;
            owner := self.owner;
            authData := mkAuthData self.owner
          };
     onlyIf : Bool := _ -- extra logic specific to swap.

  method split (self : Kudos) (partition : List (Pair ExternalIdentity Nat)) :=
     for (receiver, quantity in partition) {
        out self@{owner := receiver;
                  quantity;
                  authData := mkAuthData receiver;
      }
     };

  intent SwapIntent (wantOriginator : ExternalIdentity) (wantQuantity : Nat)
   intentLogic 
      in (give : Kudos)  -- List of resources that we consume
      want (createdKudos : Set Kudo) (unused : Set OtherObject) : Bool := 
          let kudosToGet : Nat := 
               createdKudos
              |> select \{x => owner x == owner give && originator x == wantOriginator }
              |> map quantity
              |> sum
          in kudosToGet >= wantQuantity;