/*
 * 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 Lesser 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 Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

package com.sk89q.worldedit.internal.block;

import com.google.common.collect.BiMap;
import com.google.common.collect.HashBiMap;
import com.sk89q.worldedit.world.block.BlockState;
import com.sk89q.worldedit.world.registry.BlockRegistry;

import javax.annotation.Nullable;
import java.util.BitSet;
import java.util.OptionalInt;

import static com.google.common.base.Preconditions.checkState;

public final class BlockStateIdAccess {
    /*
    private static final BiMap<BlockState, Integer> ASSIGNED_IDS = HashBiMap.create(2 << 13);

    public static OptionalInt getBlockStateId(BlockState holder) {
        Integer value = ASSIGNED_IDS.get(holder);
        return value == null ? OptionalInt.empty() : OptionalInt.of(value);
    }

    public static @Nullable BlockState getBlockStateById(int id) {
        return ASSIGNED_IDS.inverse().get(id);
    }

    /**
     * For platforms that don't have an internal ID system,
     * {@link BlockRegistry#getInternalBlockStateId(BlockState)} will return
     * {@link OptionalInt#empty()}. In those cases, we will use our own ID system,
     * since it's useful for other entries as well.
     * @return an unused ID in WorldEdit's ID tracker
     /
    private static int provideUnusedWorldEditId() {
        return usedIds.nextClearBit(0);
    }

    private static final BitSet usedIds = new BitSet();

    public static void register(BlockState blockState, OptionalInt id) {
        int i = id.orElseGet(BlockStateIdAccess::provideUnusedWorldEditId);
        BlockState existing = ASSIGNED_IDS.inverse().get(i);
        checkState(existing == null || existing == blockState,
            "BlockState %s is using the same block ID (%s) as BlockState %s",
            blockState, i, existing);
        ASSIGNED_IDS.put(blockState, i);
        usedIds.set(i);
    }

    public static void clear() {
        ASSIGNED_IDS.clear();
        usedIds.clear();
    }

    private BlockStateIdAccess() {
    }
    */
    public static OptionalInt getBlockStateId(BlockState holder) {
        return OptionalInt.of(holder.getOrdinal());
    }

    public static @Nullable BlockState getBlockStateById(int id) {
        return BlockState.getFromOrdinal(id);
    }
}
