package net.minecraft.network.protocol.game;

import it.unimi.dsi.fastutil.shorts.ShortSet;
import java.util.function.BiConsumer;
import net.minecraft.core.BlockPos;
import net.minecraft.core.SectionPos;
import net.minecraft.network.FriendlyByteBuf;
import net.minecraft.network.codec.StreamCodec;
import net.minecraft.network.protocol.Packet;
import net.minecraft.network.protocol.PacketType;
import net.minecraft.world.level.block.Block;
import net.minecraft.world.level.block.state.BlockState;
import net.minecraft.world.level.chunk.LevelChunkSection;

public class ClientboundSectionBlocksUpdatePacket implements Packet<ClientGamePacketListener> {
    public static final StreamCodec<FriendlyByteBuf, ClientboundSectionBlocksUpdatePacket> STREAM_CODEC = Packet.codec(
        ClientboundSectionBlocksUpdatePacket::write, ClientboundSectionBlocksUpdatePacket::new
    );
    private static final int POS_IN_SECTION_BITS = 12;
    private final SectionPos sectionPos;
    private final short[] positions;
    private final BlockState[] states;

    public ClientboundSectionBlocksUpdatePacket(SectionPos p_284963_, ShortSet p_285027_, LevelChunkSection p_285414_) {
        this.sectionPos = p_284963_;
        int i = p_285027_.size();
        this.positions = new short[i];
        this.states = new BlockState[i];
        int j = 0;

        for (short short1 : p_285027_) {
            this.positions[j] = short1;
            this.states[j] = p_285414_.getBlockState(SectionPos.sectionRelativeX(short1), SectionPos.sectionRelativeY(short1), SectionPos.sectionRelativeZ(short1));
            j++;
        }
    }

    private ClientboundSectionBlocksUpdatePacket(FriendlyByteBuf p_179196_) {
        this.sectionPos = SectionPos.of(p_179196_.readLong());
        int i = p_179196_.readVarInt();
        this.positions = new short[i];
        this.states = new BlockState[i];

        for (int j = 0; j < i; j++) {
            long k = p_179196_.readVarLong();
            this.positions[j] = (short)(k & 4095L);
            this.states[j] = Block.BLOCK_STATE_REGISTRY.byId((int)(k >>> 12));
        }
    }

    private void write(FriendlyByteBuf p_133002_) {
        p_133002_.writeLong(this.sectionPos.asLong());
        p_133002_.writeVarInt(this.positions.length);

        for (int i = 0; i < this.positions.length; i++) {
            p_133002_.writeVarLong((long)Block.getId(this.states[i]) << 12 | this.positions[i]);
        }
    }

    @Override
    public PacketType<ClientboundSectionBlocksUpdatePacket> type() {
        return GamePacketTypes.CLIENTBOUND_SECTION_BLOCKS_UPDATE;
    }

    public void handle(ClientGamePacketListener p_132999_) {
        p_132999_.handleChunkBlocksUpdate(this);
    }

    public void runUpdates(BiConsumer<BlockPos, BlockState> p_132993_) {
        BlockPos.MutableBlockPos blockpos$mutableblockpos = new BlockPos.MutableBlockPos();

        for (int i = 0; i < this.positions.length; i++) {
            short short1 = this.positions[i];
            blockpos$mutableblockpos.set(this.sectionPos.relativeToBlockX(short1), this.sectionPos.relativeToBlockY(short1), this.sectionPos.relativeToBlockZ(short1));
            p_132993_.accept(blockpos$mutableblockpos, this.states[i]);
        }
    }
}