public void addParameter(ActionParameter parameter)
{
if (_parameters.Contains(parameter) == false)
{
_parameters.Add(parameter);
}
else
{
throw new System.ArgumentException("The parameter: " + parameter.ToString() + " was already defined");
}
}
public List <Action> getPossibleActions()
{
List <Action> listActions = new List <Action>();
List <Action> possibleActions = new List <Action>();
foreach (Action a in _domain.Actions)
{
// The idea behind this algorithm is to first generate a dictionary which maps each entity to a
// list of possible entities suitable to be sobstituted in the action.
// Then we compute all the possible combinations of substitutions in the form of a set of tuples
Dictionary <ActionParameter, List <ActionParameter> > dictSobstitution = new Dictionary <ActionParameter, List <ActionParameter> >();
HashSet <Dictionary <ActionParameter, ActionParameter> > sobstitutions = new HashSet <Dictionary <ActionParameter, ActionParameter> >();
// For each parameter of the action we get all the possible entities in the
// current worldState which could be substituted, according to their type
foreach (ActionParameter item in a.Parameters)
{
List <ActionParameter> listapp = new List <ActionParameter>();
foreach (Entity e in _entities)
{
if (item.Type.Equals(e.Type))
{
listapp.Add(new ActionParameter(e, item.Role));
}
}
dictSobstitution.Add(item, listapp);
}
// We initialize the set of mappings with the elements of the first list
// so for example, if we had to substitute a list of waypoints
// "WAYPOINT1": [ ["WAYPOINT1": "ALPHA"]
// "ALPHA", ["WAYPOINT1": "BRAVO"]
// "BRAVO"
// ],
ActionParameter firstKey = dictSobstitution.Keys.First();
List <ActionParameter> sobList = dictSobstitution[firstKey];
foreach (ActionParameter e in sobList)
{
Dictionary <ActionParameter, ActionParameter> sobstitution = new Dictionary <ActionParameter, ActionParameter>();
sobstitution.Add(firstKey, e);
sobstitutions.Add(sobstitution);
}
dictSobstitution.Remove(firstKey);
// We iterate over the remaining lists of entities and each time we combine them
// with every element of the set of partial combinations that we already computed
foreach (KeyValuePair <ActionParameter, List <ActionParameter> > entry in dictSobstitution)
{
// entry.Key = name of the variable we are sobstituting
// entry.Value = list of possible entities we can make the sobstitution with
HashSet <Dictionary <ActionParameter, ActionParameter> > tmpSobstitutions = new HashSet <Dictionary <ActionParameter, ActionParameter> >();
foreach (Dictionary <ActionParameter, ActionParameter> sobstitution in sobstitutions)
{
foreach (ActionParameter e in entry.Value)
{
Dictionary <ActionParameter, ActionParameter> tmpSobstitution = new Dictionary <ActionParameter, ActionParameter>(sobstitution);
tmpSobstitution.Add(entry.Key, e);
tmpSobstitutions.Add(tmpSobstitution);
}
}
sobstitutions = tmpSobstitutions;
}
// Every sobstitution represents a possible action wich may or may not be
// performable in the current state, so we check if its preconditions
// are satisfied and, if so, we add it to the list of possible actions
foreach (Dictionary <ActionParameter, ActionParameter> sobstitution in sobstitutions)
{
Action action = a.sobstituteParameterInAction(sobstitution);
if (canPerformAction(action))
{
listActions.Add(action);
}
}
}
return(listActions);
}
