/*
 * WorldEdit, a Minecraft world manipulation toolkit
 * Copyright (C) sk89q <http://www.sk89q.com>
 * Copyright (C) WorldEdit team and contributors
 *
 * 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 <https://www.gnu.org/licenses/>.
 */

package com.sk89q.worldedit.function.mask;

import com.fastasyncworldedit.core.extent.filter.MaskFilter;
import com.fastasyncworldedit.core.extent.filter.block.FilterBlock;
import com.fastasyncworldedit.core.function.mask.InverseMask;
import com.fastasyncworldedit.core.queue.Filter;
import com.sk89q.worldedit.math.BlockVector3;

import javax.annotation.Nullable;
import java.util.function.Consumer;

/**
 * Tests whether a given vector meets a criteria.
 */
public interface Mask {

    /**
     * Returns true if the criteria is met.
     *
     * @param vector the vector to test
     * @return true if the criteria is met
     */
    boolean test(BlockVector3 vector);

    /**
     * Get the 2D version of this mask if one exists.
     *
     * @return a 2D mask version or {@code null} if this mask can't be 2D
     */
    @Nullable
    default Mask2D toMask2D() {
        return null;
    }

    //FAWE start

    /**
     * Returns null if no optimization took place
     * otherwise a new/same mask
     *
     * @return
     */
    @Nullable
    default Mask tryOptimize() {
        return null;
    }

    default <T extends Filter> MaskFilter<T> toFilter(T filter) {
        return new MaskFilter<>(filter, this);
    }

    default Mask tryCombine(Mask other) {
        return null;
    }

    default Mask tryOr(Mask other) {
        return null;
    }

    default Mask optimize() {
        Mask value = tryOptimize();
        return value == null ? this : value;
    }

    default Mask inverse() {
        if (this instanceof Masks.AlwaysTrue) {
            return Masks.ALWAYS_FALSE;
        } else if (this instanceof Masks.AlwaysFalse) {
            return Masks.ALWAYS_TRUE;
        } else if (this instanceof Masks.NegatedMask) {
            return ((Masks.NegatedMask) this).mask;
        }
        return new InverseMask(this);
    }

    default Filter toFilter(Consumer<FilterBlock> run) {
        return new Filter() {
            @Override
            public void applyBlock(FilterBlock block) {
                if (test(block)) {
                    run.accept(block);
                }
            }
        };
    }

    default boolean replacesAir() {
        return false;
    }

    /**
     * Returns a copy of the mask. Usually for multi-threaded operation
     *
     * @return a clone of the mask
     */
    Mask copy();
    //FAWE end
}
