/// <inheritdoc />
public OddmentTable <SabberStonePlayerTask> Create(SearchContext <List <SabberStoneAction>, SabberStoneState, SabberStoneAction, object, SabberStoneAction> context, int samplesForGeneration)
{
// So we have an issue here, because it's Hearthstone we don't know in advance how many dimensions we have.
// -> We can just evenly distribute budget over the currently available dimensions
// -- Reason is that some dimensions would be `locked' until after a specific dimensions is explored
// -> Another option is to expand all possible sequences, this might be too complex though...
// In Hearthstone we don't really have multiple available actions per dimension
// It's more like you either play/attack or not
// Although each minion can have multiple choices on what to attack
// We can still try to distillate individual actions
// It might be best to keep track of these through a dictionary/array
// So we'd randomly choose actions and simulate when `end-turn' is chosen
// And then update the value of any selected PlayerTask
// I guess use OddmentTable again?
var table = new Dictionary <SabberStonePlayerTask, double>(PlayerTaskComparer.Comparer);
// So, we have a number of samples to use
// For each of those, generate a random SabberStoneAction and playout
for (var i = 0; i < samplesForGeneration; i++)
{
var action = PlayoutBot.CreateRandomAction(context.Source);
var newState = GameLogic.Apply(context, (SabberStoneState)context.Source.Copy(), action);
var endState = Playout.Playout(context, newState);
var value = Evaluation.Evaluate(context, null, endState);
foreach (var task in action.Tasks)
{
if (!table.ContainsKey(task))
{
table.Add(task, 0);
}
table[task] += value;
}
}
// Create the Oddment table
var oddmentTable = new OddmentTable <SabberStonePlayerTask>();
foreach (var kvPair in table)
{
oddmentTable.Add(kvPair.Key, kvPair.Value, recalculate: false);
}
oddmentTable.Recalculate();
return(oddmentTable);
}
/// <summary>
/// Selects the best half of a collection of actions by evaluating them based on the provided search context.
/// </summary>
/// <param name="context">The current search context.</param>
/// <param name="actions">The collection of actions to filter.</param>
/// <param name="samplesPerAction">How many samples to run per action.</param>
/// <returns>Collection of actions which Count is half of the original collection, rounded up. This collection is ordered by descending value.</returns>
private List <ActionValue> SelectBestHalf(SearchContext <D, P, A, S, A> context, IReadOnlyCollection <ActionValue> actions, int samplesPerAction)
{
var clone = context.Cloner;
// Evaluate each action by running a playout for it.
foreach (var item in actions)
{
var tempNode = new N {
Payload = item.Action
};
var newState = GameLogic.Apply(context, clone.Clone(context.Source), item.Action);
double value = 0;
for (var i = 0; i < samplesPerAction; i++)
{
try {
var endState = Playout.Playout(context, clone.Clone(newState));
value += Evaluation.Evaluate(context, tempNode, endState);
SamplesUsedEvaluation++;
}
catch (Exception e) {
//Console.WriteLine($"ERROR: {e.GetType()} while cloning state.");
// TODO fix
// Cloning here seems to very seldom cause a NullReference in the SabberStone dll
// I believe failing and just using 0 as a value here is acceptable
}
}
item.Value = value;
}
// Return the half with the highest value.
var half = (int)Math.Max(1, Math.Ceiling(actions.Count / 2.0));
return(actions.OrderByDescending(i => i.Value).Take(half).ToList());
}