% This Source Code Form is subject to the terms of the Mozilla Public
% License, v. 2.0. If a copy of the MPL was not distributed with this
% file, You can obtain one at http://mozilla.org/MPL/2.0/.

  %DEFINES
container(solid; onthefly; llvm_const_array). 
access(serial; rand).
relation(recommends; satisfied; unsupported).
score(-1..1).


  %DOMAIN FACTS
relation_score(
  unsupported, -1;
  satisfied, 0;
  recommends, 1
).

relation_access(
  serial, onthefly, recommends;
  rand, llvm_const_array, recommends;
  rand, onthefly, unsupported
).
  
        
  %AST ATTACHMENTS
attach_operator_map(none, access(serial)).
attach_operator_fold(none, access(serial), none).

attach_operator_list_range(container(onthefly)).
attach_operator_list(container(solid)).
attach_operator_index(access(rand)).

  %CLUSTERS
cluster_link(VTo, VFrom):-                %aliases
  dfa_connection(VTo, VFrom, strong).
  
cluster_link(VResult, VSource):-          %Operator MAP
  ast_op_map(VResult, VSource, _).
  
cluster_root(V):- 
  not cluster_link(V, _);
  v(V).

var_cluster(V, V):-                       %self referencing
  cluster_root(V).
  
var_cluster(VRoot, VTo):-                 %propagation down the tree
  cluster_link(VTo, VFrom);
  var_cluster(VRoot, VFrom).
  
  
  %ALGORITHM  
-impl_fulfill(OP, IMPL):- 
  relation_op(OP, IMPL, unsupported).
  
impl_fulfill(OP, IMPL, SCORE):- 
  SCORE = #sum{SCORE1, (OP, IMPL, RL): relation_op(OP, IMPL, RL), relation_score(RL, SCORE1)};
  not -impl_fulfill(OP, IMPL);
  access(OP); container(IMPL).
    
-impl_fulfill_cluster(Var0, Impl):- 
  var_cluster(Var0, Var_Any); 
  bind(Var_Any, access(Op)); 
  -impl_fulfill(Op, Impl).
  
impl_fulfill_cluster(VAR0, IMPL, Score):- 
    Score = #sum{SCORE, (OP, IMPL, VAR_ANY): impl_fulfill(OP, IMPL, SCORE), var_cluster(VAR0, VAR_ANY), bind(VAR_ANY, access(OP))};
  bind(VAR0, container(IMPL)); 
  cluster_root(VAR0); 
  not -impl_fulfill_cluster(VAR0, IMPL).
  
  
  %OUTPUT
containers_impl(V, Impl):-
  containers_impl(VRoot, Impl);
  var_cluster(VRoot, V).

containers_impl(V, solid(Size)):-
  impl_fulfill_cluster(V, solid, _);
  ast_op_list(V, Size);
  cluster_root(V).
  
containers_impl(V, onthefly):-
  impl_fulfill_cluster(V, onthefly, _);
  ast_op_list_range(V);
  cluster_root(V).  
  
%optimization
%  #maximize {SCORE, (VAR0, IMPL) : impl_fulfill_cluster(VAR0, IMPL, SCORE)}.

#show var_cluster/2.
#show impl_fulfill_cluster/3.