flesh out epsilon-greedy destination supplier

and lots of things around it, notably the idea of Evaluator and
Evaluation objects to generate values for possible choices

agents/src/main/java/uk/ac/ox/poseidon/agents/behaviours/choices/AveragingOptionValuesFactory.java

@@ -0,0 +1,30 @@
+/*
+ * POSEIDON: an agent-based model of fisheries
+ * Copyright (c) 2024 CoHESyS Lab [email protected]
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package uk.ac.ox.poseidon.agents.behaviours.choices;
+
+import uk.ac.ox.poseidon.core.Factory;
+import uk.ac.ox.poseidon.core.Simulation;
+
+public class AveragingOptionValuesFactory<O> implements Factory<OptionValues<O>> {
+    @Override
+    public OptionValues<O> get(final Simulation simulation) {
+        return new AveragingOptionValues<>();
+    }
+}

agents/src/main/java/uk/ac/ox/poseidon/agents/behaviours/destination/EpsilonGreedyDestinationSupplier.java → agents/src/main/java/uk/ac/ox/poseidon/agents/behaviours/choices/EpsilonGreedyChooser.java

@@ -17,43 +17,55 @@
  *
  */
 
-package uk.ac.ox.poseidon.agents.behaviours.destination;
+package uk.ac.ox.poseidon.agents.behaviours.choices;
 
+import com.google.common.collect.ImmutableList;
 import ec.util.MersenneTwisterFast;
-import sim.util.Int2D;
 
+import java.util.List;
 import java.util.function.Supplier;
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
+import static uk.ac.ox.poseidon.core.MasonUtils.oneOf;
 
-class EpsilonGreedyDestinationSupplier implements DestinationSupplier {
+public class EpsilonGreedyChooser<O> implements Supplier<O> {
 
+    private final ImmutableList<O> options;
     private final double epsilon;
-    private final Supplier<Int2D> greedyDestinationSupplier;
-    private final Supplier<Int2D> nonGreedyDestinationSupplier;
+    private final OptionValues<O> optionValues;
+    private final Evaluator<O> evaluator;
     private final MersenneTwisterFast rng;
+    private O currentOption;
+    private Evaluation currentEvaluation;
 
-    EpsilonGreedyDestinationSupplier(
+    public EpsilonGreedyChooser(
         final double epsilon,
-        final Supplier<Int2D> greedyDestinationSupplier,
-        final Supplier<Int2D> nonGreedyDestinationSupplier,
+        final List<O> options,
+        final OptionValues<O> optionValues,
+        final Evaluator<O> evaluator,
         final MersenneTwisterFast rng
     ) {
+        this.options = ImmutableList.copyOf(options);
+        this.optionValues = checkNotNull(optionValues);
+        this.evaluator = checkNotNull(evaluator);
         checkArgument(
             epsilon >= 0 && epsilon <= 1,
             "epsilon must be between 0 and 1"
         );
         this.epsilon = epsilon;
-        this.greedyDestinationSupplier = checkNotNull(greedyDestinationSupplier);
-        this.nonGreedyDestinationSupplier = checkNotNull(nonGreedyDestinationSupplier);
         this.rng = checkNotNull(rng);
     }
 
     @Override
-    public Int2D get() {
-        return rng.nextBoolean(epsilon)
-            ? greedyDestinationSupplier.get()
-            : nonGreedyDestinationSupplier.get();
+    public O get() {
+        if (currentOption != null) {
+            optionValues.observe(currentOption, currentEvaluation.getResult());
+        }
+        final List<O> bestOptions = optionValues.getBestOptions();
+        final boolean explore = bestOptions.isEmpty() || rng.nextDouble() < epsilon;
+        currentOption = oneOf(explore ? options : bestOptions, rng);
+        currentEvaluation = evaluator.newEvaluation(currentOption);
+        return currentOption;
     }
 }

agents/src/main/java/uk/ac/ox/poseidon/agents/behaviours/choices/Evaluation.java

@@ -0,0 +1,25 @@
+/*
+ * POSEIDON: an agent-based model of fisheries
+ * Copyright (c) 2024 CoHESyS Lab [email protected]
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package uk.ac.ox.poseidon.agents.behaviours.choices;
+
+@FunctionalInterface
+public interface Evaluation {
+    double getResult();
+}

agents/src/main/java/uk/ac/ox/poseidon/agents/behaviours/choices/Evaluator.java

@@ -0,0 +1,24 @@
+/*
+ * POSEIDON: an agent-based model of fisheries
+ * Copyright (c) 2024 CoHESyS Lab [email protected]
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package uk.ac.ox.poseidon.agents.behaviours.choices;
+
+public interface Evaluator<O> {
+    Evaluation newEvaluation(O option);
+}

agents/src/main/java/uk/ac/ox/poseidon/agents/behaviours/destination/DestinationSupplier.java

@@ -23,5 +23,6 @@
 
 import java.util.function.Supplier;
 
+@FunctionalInterface
 public interface DestinationSupplier extends Supplier<Int2D> {
 }

agents/src/main/java/uk/ac/ox/poseidon/agents/behaviours/destination/EpsilonGreedyDestinationSupplierFactory.java

@@ -0,0 +1,64 @@
+/*
+ * POSEIDON: an agent-based model of fisheries
+ * Copyright (c) 2024 CoHESyS Lab [email protected]
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package uk.ac.ox.poseidon.agents.behaviours.destination;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import sim.util.Int2D;
+import uk.ac.ox.poseidon.agents.behaviours.choices.EpsilonGreedyChooser;
+import uk.ac.ox.poseidon.agents.behaviours.choices.Evaluator;
+import uk.ac.ox.poseidon.agents.behaviours.choices.OptionValues;
+import uk.ac.ox.poseidon.agents.vessels.Vessel;
+import uk.ac.ox.poseidon.agents.vessels.VesselScopeFactory;
+import uk.ac.ox.poseidon.core.Factory;
+import uk.ac.ox.poseidon.core.Simulation;
+import uk.ac.ox.poseidon.geography.bathymetry.BathymetricGrid;
+import uk.ac.ox.poseidon.geography.paths.PathFinder;
+
+@Getter
+@Setter
+@NoArgsConstructor
+@AllArgsConstructor
+public class EpsilonGreedyDestinationSupplierFactory extends VesselScopeFactory<DestinationSupplier> {
+
+    private double epsilon;
+    private Factory<? extends BathymetricGrid> bathymetricGrid;
+    private Factory<? extends PathFinder<Int2D>> pathFinder;
+    private Factory<? extends OptionValues<Int2D>> optionValues;
+    private VesselScopeFactory<? extends Evaluator<Int2D>> destinationEvaluator;
+
+    @Override
+    protected DestinationSupplier newInstance(
+        final Simulation simulation,
+        final Vessel vessel
+    ) {
+        return new EpsilonGreedyChooser<>(
+            epsilon,
+            bathymetricGrid
+                .get(simulation)
+                .getAccessibleCells(vessel.getCurrentCell(), pathFinder.get(simulation)),
+            optionValues.get(simulation),
+            destinationEvaluator.get(simulation, vessel),
+            simulation.random
+        )::get;
+    }
+}

agents/src/main/java/uk/ac/ox/poseidon/agents/behaviours/destination/RandomDestinationSupplierFactory.java

@@ -31,8 +31,6 @@
 import uk.ac.ox.poseidon.geography.bathymetry.BathymetricGrid;
 import uk.ac.ox.poseidon.geography.paths.PathFinder;
 
-import static com.google.common.collect.ImmutableList.toImmutableList;
-
 @Getter
 @Setter
 @NoArgsConstructor
@@ -45,17 +43,14 @@ public class RandomDestinationSupplierFactory
 
     @Override
     protected DestinationSupplier newInstance(
-        Simulation simulation,
-        Vessel vessel
+        final Simulation simulation,
+        final Vessel vessel
     ) {
-        PathFinder<Int2D> pathFinder = this.pathFinder.get(simulation);
+        final PathFinder<Int2D> pathFinder = this.pathFinder.get(simulation);
         return new RandomDestinationSupplier(
             bathymetricGrid
                 .get(simulation)
-                .getWaterCells()
-                .stream()
-                .filter(cell -> pathFinder.getPath(vessel.getCurrentCell(), cell).isPresent())
-                .collect(toImmutableList()),
+                .getAccessibleCells(vessel.getCurrentCell(), pathFinder),
             simulation.random
         );
     }

agents/src/main/java/uk/ac/ox/poseidon/agents/behaviours/destination/TotalBiomassCaughtPerHourDestinationEvaluatorFactory.java

@@ -0,0 +1,68 @@
+/*
+ * POSEIDON: an agent-based model of fisheries
+ * Copyright (c) 2024 CoHESyS Lab [email protected]
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package uk.ac.ox.poseidon.agents.behaviours.destination;
+
+import sim.util.Int2D;
+import uk.ac.ox.poseidon.agents.behaviours.Action;
+import uk.ac.ox.poseidon.agents.behaviours.choices.Evaluator;
+import uk.ac.ox.poseidon.agents.behaviours.fishing.FishingAction;
+import uk.ac.ox.poseidon.agents.vessels.Vessel;
+import uk.ac.ox.poseidon.agents.vessels.VesselScopeFactory;
+import uk.ac.ox.poseidon.core.Simulation;
+import uk.ac.ox.poseidon.core.events.CombiningEphemeralAccumulatingListener;
+
+public class TotalBiomassCaughtPerHourDestinationEvaluatorFactory
+    extends VesselScopeFactory<Evaluator<Int2D>> {
+
+    @Override
+    protected Evaluator<Int2D> newInstance(
+        final Simulation simulation,
+        final Vessel vessel
+    ) {
+        return option -> new Evaluation(vessel);
+    }
+
+    private static class Evaluation implements uk.ac.ox.poseidon.agents.behaviours.choices.Evaluation {
+
+        private final CombiningEphemeralAccumulatingListener
+            <FishingAction, Double, Action, Double, Double> listener;
+
+        private Evaluation(final Vessel vessel) {
+            listener = new CombiningEphemeralAccumulatingListener<>(
+                vessel.getEventManager(),
+                FishingAction.class,
+                0.0,
+                (caughtSoFar, fishingAction) -> caughtSoFar + fishingAction.getTotalBiomassCaught(),
+                Action.class,
+                0.0,
+                (hoursSoFar, action) ->
+                    vessel.isAtPort()
+                        ? hoursSoFar
+                        : hoursSoFar + action.getDuration().getSeconds() / 3600.0,
+                (caught, hours) -> caught / hours
+            );
+        }
+
+        @Override
+        public double getResult() {
+            return listener.get();
+        }
+    }
+}

agents/src/main/java/uk/ac/ox/poseidon/agents/behaviours/fishing/DefaultFishingBehaviour.java

@@ -53,18 +53,23 @@ public Action newAction(
 
     @Getter
     @ToString(callSuper = true)
-    public class Fishing extends Action {
+    public class Fishing extends FishingAction {
 
         Bucket<C> fishCaught;
 
-        public Fishing(
+        private Fishing(
             final LocalDateTime start,
             final Duration duration,
             final Vessel vessel
         ) {
             super(start, duration, vessel);
         }
 
+        @Override
+        public double getTotalBiomassCaught() {
+            return fishCaught.getTotalBiomass().getValue();
+        }
+
         @Override
         protected Action complete(
             final LocalDateTime dateTime

agents/src/main/java/uk/ac/ox/poseidon/agents/behaviours/fishing/FishingAction.java

@@ -0,0 +1,39 @@
+/*
+ * POSEIDON: an agent-based model of fisheries
+ * Copyright (c) 2024 CoHESyS Lab [email protected]
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package uk.ac.ox.poseidon.agents.behaviours.fishing;
+
+import uk.ac.ox.poseidon.agents.behaviours.Action;
+import uk.ac.ox.poseidon.agents.vessels.Vessel;
+
+import java.time.Duration;
+import java.time.LocalDateTime;
+
+public abstract class FishingAction extends Action {
+
+    public FishingAction(
+        final LocalDateTime start,
+        final Duration duration,
+        final Vessel vessel
+    ) {
+        super(start, duration, vessel);
+    }
+
+    public abstract double getTotalBiomassCaught();
+}