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) 2017-2021 Vincent Quatrevieux

 */

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

import fr.arakne.utils.maps.constant.Direction;

import fr.arakne.utils.maps.path.Decoder;

import fr.arakne.utils.maps.path.Pathfinder;

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

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

import java.util.Arrays;

import java.util.Optional;

import java.util.stream.Stream;

import java.util.stream.StreamSupport;

/**

 * Utility class for perform operation on map cells

 *

 * @see AIHelper#cells()

 */

public final class CellsHelper {

    private final AI ai;

    private Decoder<FightCell> decoder;

    CellsHelper(AI ai) {

        this.ai = ai;

    }

    /**

     * Get all available cells

     * A cell is considered available when it's walkable without consider fighters

     *

     * @return Stream of all targetable cells

     */

    /**

     * Get cells which is adjacent to the fighter

     * Adjacent cells are cells directly accessible through the four restricted directions (i.e. {@link Direction#restrictedDirections()})

     *

     * @return Stream of cells adjacent to the current cell

     *

     * @see FightersHelper#adjacent() To check adjacent fighters

     */

    public Stream<FightCell> adjacent() {

        return adjacent(ai.fighter().cell());

    }

    /**

     * Get cells which is adjacent to the given cell

     * Adjacent cells are cells directly accessible through the four restricted directions (i.e. {@link Direction#restrictedDirections()})

     *

     * @param cell Cell to check

     *

     * @return Stream of cells adjacent to the given cell

     *

     * @see FightersHelper#adjacent(FightCell) To check adjacent fighters

     */

    public Stream<FightCell> adjacent(FightCell cell) {

        return Arrays.stream(Direction.restrictedDirections())

            .map(direction -> decoder.nextCellByDirection(cell, direction))

            .filter(Optional::isPresent)

            .map(Optional::get)

            .filter(FightCell::walkableIgnoreFighter)

        ;

    }

    /**

     * Create a new instance of the pathfinder

     */

    public Pathfinder<FightCell> pathfinder() {

        return decoder().pathfinder();

    }

    private Decoder<FightCell> decoder() {

        if (decoder == null) {

            decoder = new Decoder<>(ai.map());

        }

        return decoder;

    }

}