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) 2017-2019 Vincent Quatrevieux

 */

package fr.quatrevieux.araknemu.game.fight.castable.effect.handler.characteristic;

import fr.quatrevieux.araknemu.data.constant.Characteristic;

import fr.quatrevieux.araknemu.game.fight.Fight;

import fr.quatrevieux.araknemu.game.fight.castable.FightCastScope;

import fr.quatrevieux.araknemu.game.fight.castable.Castable;

import fr.quatrevieux.araknemu.game.fight.castable.effect.EffectValue;

import fr.quatrevieux.araknemu.game.fight.castable.effect.buff.Buff;

import fr.quatrevieux.araknemu.game.fight.castable.effect.buff.BuffEffect;

import fr.quatrevieux.araknemu.game.fight.castable.effect.handler.EffectHandler;

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

import fr.quatrevieux.araknemu.game.spell.effect.SpellEffect;

import org.checkerframework.checker.index.qual.NonNegative;

import java.util.function.BiConsumer;

/**

 * Steal a characteristic from a fighter to give to the caster

 * A configured effect id will be used for both add and remove characteristic buff effects

 *

 * This effect is equivalent of chaining {@link RemoveCharacteristicHandler} and {@link AddCharacteristicHandler} effects

 *

 * @see AlterCharacteristicHook

 */

public class StealCharacteristicHandler implements EffectHandler {

    private final AlterCharacteristicHook addHook;

    private final AlterCharacteristicHook removeHook;

    private final int addEffectId;

    private final int removeEffectId;

    /**

     * @param fight Fight where the effect takes effect

     * @param characteristic Characteristic to steal

     * @param addEffectId Spell effect id used as "add characteristic" effect

     * @param removeEffectId Spell effect id used as "remove characteristic" effect

     */

    }

    /**

     * @param addHook Buff used for add characteristic to caster

     * @param addEffectId Spell effect id used as "add characteristic" effect

     * @param removeHook Buff used for remove characteristic from targets

     * @param removeEffectId Spell effect id used as "remove characteristic" effect

     */

    protected StealCharacteristicHandler(AlterCharacteristicHook addHook, int addEffectId, AlterCharacteristicHook removeHook, int removeEffectId) {

        this.addHook = addHook;

        this.removeHook = removeHook;

        this.addEffectId = addEffectId;

        this.removeEffectId = removeEffectId;

    }

    @Override

    public void handle(FightCastScope cast, FightCastScope.EffectScope effect) {

        throw new UnsupportedOperationException("Alter characteristic effect must be used as a buff");

    }

    @Override

    public final void buff(FightCastScope cast, FightCastScope.EffectScope effect) {

        final SpellEffect spellEffect = effect.effect();

        final Fighter caster = cast.caster();

        final Castable action = cast.action();

        final Applier applier = new Applier(caster, spellEffect, action);

        EffectValue.forEachTargets(spellEffect, caster, effect.targets(), applier);

        if (applier.total() > 0) {

            caster.buffs().add(new Buff(

                BuffEffect.withCustomEffect(spellEffect, addEffectId, applier.total()),

                action,

                caster,

                caster,

                addHook

            ));

        }

    }

    /**

     * Apply removal effect to target

     */

    private class Applier implements BiConsumer<Fighter, EffectValue> {

        private final Fighter caster;

        private final SpellEffect spellEffect;

        private final Castable action;

        private @NonNegative int total = 0;

        public Applier(Fighter caster, SpellEffect spellEffect, Castable action) {

            this.caster = caster;

            this.spellEffect = spellEffect;

            this.action = action;

        }

        @Override

        public void accept(Fighter target, EffectValue effectValue) {

            final int value = effectValue.value();

            total += value;

            target.buffs().add(new Buff(

                BuffEffect.withCustomEffect(spellEffect, removeEffectId, value),

                action,

                caster,

                target,

                removeHook

            ));

        }

        /**

         * Total stolen characteristic value

         */

        public @NonNegative int total() {

            return total;

        }

    }

}