private int _evaluateForRight(EvaluationData <GP> evaluationData)
{
(Maybe <EvaluationRecord> toad, Maybe <EvaluationRecord> frog)cached =
_cache.Lookup(evaluationData.Position);
if (cached.frog.HasValue && cached.frog.Value.IsComplete)
{
return(cached.frog.Value.Value);
}
OptionRecord optionRecord =
new OptionRecord(
evaluationData.Position.GetRightOptions(),
int.MaxValue,
cached.frog
);
if (optionRecord.NoPossibleMoves)
{
return(EvaluateEndPositionForLeft(evaluationData.Position));
}
EvaluationRecord record = _updateEvaluation(
evaluationData,
optionRecord,
_evaluateForLeft,
(x, y) => Math.Min(x, y),
x => (evaluationData.BestLeft, Math.Min(x, evaluationData.BestRight)));
_cache.Store(evaluationData.Position, (cached.toad, record.ToMaybe()));
return(record.Value);
}
private EvaluationRecord _updateEvaluation(
EvaluationData <GP> evaluationData,
OptionRecord optionRecord,
_evaluator nextEvaluator,
_bestValueUpdater bestValueUpdater,
_bestPairUpdater bestPairUpdater)
{
EvaluationData <GP> resultingEvaluationData;
int bestToad = evaluationData.BestLeft;
int bestFrog = evaluationData.BestRight;
int optionEvaluationcount = 0;
int bestValue = optionRecord.BestValueSoFar;
List <GamePosition> evaluatedOptions =
optionRecord.EvaluatedOptions;
foreach (GP option in optionRecord.OptionsToEvaluate)
{
optionEvaluationcount++;
evaluatedOptions.Add(option);
resultingEvaluationData = new EvaluationData <GP>(
option,
evaluationData.Depth + 1,
evaluationData.BestLeft,
evaluationData.BestRight);
bestValue =
bestValueUpdater(
bestValue,
nextEvaluator(resultingEvaluationData));
(bestToad, bestFrog) = bestPairUpdater(bestValue);
if (bestToad > bestFrog)
{
break;
}
}
return
(optionEvaluationcount == optionRecord.OptionsToEvaluate.Count
? new EvaluationRecord(bestValue)
: new EvaluationRecord(bestValue, evaluatedOptions));
}