private ActionDef ParseActionDef(
Tokenizer tok,
Dictionary <string, ActionDef> parsedActions)
{
var posPre = new HashSet <VariableRelation>();
var negPre = new HashSet <VariableRelation>();
var posPost = new HashSet <VariableRelation>();
var negPost = new HashSet <VariableRelation>();
string name = tok.Consume(TokenType.Id).Value;
// Signature
var parameters = ParseSignature(tok);
var paramVars = parameters
.ToDictionary(k => k.Name);
// Optional Dependent Actions
while (tok.PeekType() == TokenType.LParen)
{
tok.Consume(TokenType.LParen);
// Dependent Action
if (tok.PeekType() == TokenType.Id)
{
var depAction = ParseDependentAction(tok, parsedActions, paramVars);
posPre.AddRange(depAction.PositivePreconditions);
negPre.AddRange(depAction.NegativePreconditions);
posPost.AddRange(depAction.PositivePostconditions);
negPost.AddRange(depAction.NegativePostconditions);
}
// Pre Expression
else if (tok.PeekType() == TokenType.Pre)
{
tok.Consume(TokenType.Pre);
if (tok.PeekToken().Type != TokenType.RParen)
{
var propDefs = ParseVariableRelations(paramVars, tok);
foreach (var pd in propDefs)
{
var b = pd.Negated ? negPre.Add(pd) : posPre.Add(pd);
}
}
}
// Post Expression
else if (tok.PeekType() == TokenType.Post)
{
tok.Consume(TokenType.Post);
if (tok.PeekToken().Type != TokenType.RParen)
{
var propDefs = ParseVariableRelations(paramVars, tok);
foreach (var pd in propDefs)
{
var b = pd.Negated ? negPost.Add(pd) : posPost.Add(pd);
}
}
}
tok.Consume(TokenType.RParen);
}
tok.Consume(TokenType.RParen);
var ret = new ActionDef(
name,
paramVars.Values.ToArray(),
posPre,
negPre,
posPost,
negPost
);
return(ret);
}
public Action(ActionDef def, uint[] parameters)
{
Definition = def;
Parameters = parameters;
}
public IEnumerable <Action> GetActionsForActionDef(ActionDef ad)
{
ParamSet knownSet = null;
var names = Facts
.Select(p => p.Value.AId)
.ToArray();
// If action has no parameters
if (ad.Parameters.Length == 0)
{
yield break;
}
// Each N+V gets mapped to a paramIdx
foreach (VariableRelation varRelation in ad.PositivePreconditions)
{
IEnumerable <Fact> facts = null;
int[] valueIdxs = null;
// Exit if no matches found
if (knownSet != null && !knownSet.Params.Any())
{
break;
}
// R L R
else if (varRelation.A.IsFree && varRelation.Rel.IsBound && varRelation.B.IsFree)
{
uint property = varRelation.Rel.Id;
if (!Rel.Value.ContainsKey(property))
{
yield break;
}
facts = Rel.Value[property];
valueIdxs = new[] { varRelation.A.Idx, varRelation.B.Idx };
}
// R L L
else if (varRelation.A.IsFree && varRelation.Rel.IsBound && varRelation.B.IsBound)
{
uint prop = varRelation.Rel.Id;
if (!Rel.Value.ContainsKey(prop))
{
yield break;
}
facts = Rel.Value[prop].Where(p => p.BId == varRelation.B.Id);
valueIdxs = new[] { varRelation.A.Idx };
}
// L L L
else if (varRelation.A.IsBound && varRelation.Rel.IsBound && varRelation.B.IsBound)
{
throw new NotImplementedException();
}
// R R R
else if (varRelation.A.IsFree && varRelation.Rel.IsFree && varRelation.B.IsFree)
{
facts = Facts.Values;
valueIdxs = new[] {
varRelation.A.Idx,
varRelation.Rel.Idx,
varRelation.B.Idx
};
}
else
{
throw new NotImplementedException();
}
// Convert Preds to Param objects
var validParams = facts
.Select(proposition => {
var ret = new uint[ad.Parameters.Length];
if (varRelation.A.IsFree)
{
ret[varRelation.A.Idx] = proposition.AId;
}
if (varRelation.Rel.IsFree)
{
ret[varRelation.Rel.Idx] = proposition.RelId;
}
if (varRelation.B.IsFree)
{
ret[varRelation.B.Idx] = proposition.BId;
}
return(ret);
})
.ToList();
// If first Proposition
if (knownSet == null)
{
knownSet = new ParamSet(validParams, valueIdxs);
}
// Join known param with new params
else
{
var newSet = new ParamSet(validParams, valueIdxs);
knownSet = knownSet.Join(newSet);
}
}
if (knownSet != null)
{
knownSet = knownSet.Expand(names);
}
foreach (VariableRelation varRelation in ad.NegativePreconditions)
{
IEnumerable <Fact> props = null;
int[] valueIdxs = null;
// Exit if no matches found
if (knownSet != null && !knownSet.Params.Any())
{
break;
}
// R L R
else if (varRelation.A.IsFree && varRelation.Rel.IsBound && varRelation.B.IsFree)
{
uint prop = varRelation.Rel.Id;
if (!Rel.Value.ContainsKey(prop))
{
break;
}
props = Rel.Value[prop];
valueIdxs = new[] { varRelation.A.Idx, varRelation.B.Idx };
}
// R L L
else if (varRelation.A.IsFree && varRelation.Rel.IsBound && varRelation.B.IsBound)
{
uint prop = varRelation.Rel.Id;
if (!Rel.Value.ContainsKey(prop))
{
break;
}
props = Rel.Value[prop]
.Where(p => p.BId == varRelation.B.Id);
valueIdxs = new[] { varRelation.A.Idx };
}
// L L L
else if (varRelation.A.IsBound && varRelation.Rel.IsBound && varRelation.B.IsBound)
{
throw new NotImplementedException();
}
// R R R
else
{
props = Facts.Values;
valueIdxs = new[] { varRelation.A.Idx, varRelation.Rel.Idx, varRelation.B.Idx };
}
// Convert Propositions to Param objects
var toRemove = props
.Select(prop => {
var ret = new uint[ad.Parameters.Length];
if (varRelation.A.IsFree)
{
ret[varRelation.A.Idx] = prop.AId;
}
if (varRelation.Rel.IsFree)
{
ret[varRelation.Rel.Idx] = prop.RelId;
}
if (varRelation.B.IsFree)
{
ret[varRelation.B.Idx] = prop.BId;
}
return(ret);
})
.ToList();
// If first Proposition
if (knownSet == null)
{
knownSet = new ParamSet(toRemove, valueIdxs);
}
// Remove invalid propositions from KnownSet
else
{
var newSet = new ParamSet(toRemove, valueIdxs);
knownSet = knownSet.Except(newSet);
}
}
if (knownSet != null)
{
knownSet = knownSet.Expand(names);
foreach (var action in knownSet.Params.Select(p => new Action(ad, p)))
{
yield return(action);
}
}
}