Arakne / Araknemu

 * This file is part of Araknemu.

 *

 * Araknemu is free software: you can redistribute it and/or modify

 * it under the terms of the GNU Lesser General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * Araknemu 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 Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with Araknemu.  If not, see <https://www.gnu.org/licenses/>.

 *

 * Copyright (c) 2017-2020 Vincent Quatrevieux

 */

package fr.quatrevieux.araknemu.game.fight.ai.action;

import fr.arakne.utils.maps.CoordinateCell;

import fr.quatrevieux.araknemu.game.fight.ai.AI;

import fr.quatrevieux.araknemu.game.fight.ai.action.util.Movement;

import fr.quatrevieux.araknemu.game.fight.ai.util.AIHelper;

import fr.quatrevieux.araknemu.game.fight.fighter.ActiveFighter;

import fr.quatrevieux.araknemu.game.fight.map.BattlefieldCell;

import fr.quatrevieux.araknemu.game.fight.turn.action.Action;

import org.checkerframework.checker.nullness.util.NullnessUtil;

import java.util.Collections;

import java.util.List;

import java.util.Optional;

import java.util.stream.Collectors;

/**

 * Try to move far all enemies

 *

 * The selected cell is the cell with the highest distance from the nearest enemy

 * Select only cells with higher distance than current cell

 */

public final class MoveFarEnemies<F extends ActiveFighter> implements ActionGenerator<F> {

    private final Movement<F> movement;

    private List<CoordinateCell<BattlefieldCell>> enemiesCells = Collections.emptyList();

    @Override

    public void initialize(AI<F> ai) {

        movement.initialize(ai);

    }

    @Override

    public Optional<Action> generate(AI<F> ai, AiActionFactory actions) {

        final AIHelper helper = ai.helper();

        if (!helper.canMove()) {

            return Optional.empty();

        }

        enemiesCells = helper.enemies().cells().map(BattlefieldCell::coordinate).collect(Collectors.toList());

        return movement.generate(ai, actions);

    }

    /**

     * The score function

     *

     * Select the highest distance

     */

    private double score(CoordinateCell<BattlefieldCell> cell) {

        return NullnessUtil.castNonNull(enemiesCells).stream().mapToDouble(cell::distance).min().orElse(0);

    }

}