/// <summary>
/// Concertize the SFA by including at most k characters in the label.
/// </summary>
/// <param name="k">upper limit on the number of included characters in the output automaton, when 0 or negative then include all elements</param>
/// <returns></returns>
public Automaton <BDD> Concretize(int k = 0)
{
//if (k <= 0)
// throw new AutomataException(AutomataExceptionKind.InvalidArgument);
var mem = new Dictionary <TERM, BDD>();
var concrete_moves = new List <Move <BDD> >();
var moveMap = new Dictionary <Tuple <int, int>, BDD>();
Action <int, int, BDD> AddMove = (from, to, guard) =>
{
BDD pred;
var key = new Tuple <int, int>(from, to);
if (moveMap.TryGetValue(key, out pred))
{
pred = solver.CharSetProvider.MkOr(pred, guard);
}
else
{
pred = guard;
}
moveMap[key] = pred;
};
Predicate <TERM> IsGround = t =>
{
foreach (var v in solver.GetVars(t))
{
return(false);
}
return(true);
};
foreach (var move in automaton.GetMoves())
{
if (move.IsEpsilon)
{
concrete_moves.Add(Move <BDD> .Epsilon(move.SourceState, move.TargetState));
continue;
}
BDD set;
if (mem.TryGetValue(move.Label, out set))
{
AddMove(move.SourceState, move.TargetState, set);
//concrete_moves.Add(Move<BvSet>.M(move.SourceState, move.TargetState, set));
continue;
}
if (k > 0)
{
if (IsGround(move.Label)) //must be satisfiable so same as true
{
set = solver.CharSetProvider.MkRangeConstraint((char)0, (char)(k - 1));
mem[move.Label] = set;
AddMove(move.SourceState, move.TargetState, set);
//concrete_moves.Add(Move<BvSet>.M(move.SourceState, move.TargetState, set));
continue;
}
var elems = new List <uint>();
foreach (var v in solver.MainSolver.FindAllMembers(move.Label))
{
elems.Add(solver.GetNumeralUInt(v.Value));
if (elems.Count == k)
{
break;
}
}
set = solver.CharSetProvider.MkSetFromElements(elems, ((int)solver.CharSetProvider.Encoding) - 1);
mem[move.Label] = set;
AddMove(move.SourceState, move.TargetState, set);
//concrete_moves.Add(Move<BvSet>.M(move.SourceState, move.TargetState, set));
}
else
{
BDD cond = solver.ConvertToCharSet(solver.CharSetProvider, move.Label);
if (cond != null)
{
throw new AutomataException(AutomataExceptionKind.ConditionCannotBeConvertedToCharSet);
}
mem[move.Label] = cond;
AddMove(move.SourceState, move.TargetState, cond);
//concrete_moves.Add(Move<BvSet>.M(move.SourceState, move.TargetState, cond));
}
}
foreach (var entry in moveMap)
{
concrete_moves.Add(Move <BDD> .Create(entry.Key.Item1, entry.Key.Item2, entry.Value));
}
var res = Automaton <BDD> .Create(this.solver.CharSetProvider, this.automaton.InitialState, this.automaton.GetFinalStates(), concrete_moves);
return(res);
}
