Code/net/minecraft/world/level/pathfinder/Path.java

package net.minecraft.world.level.pathfinder;

import java.util.HashSet;
import java.util.List;
import java.util.Set;
import javax.annotation.Nullable;
import net.minecraft.core.BlockPos;
import net.minecraft.network.FriendlyByteBuf;
import net.minecraft.util.VisibleForDebug;
import net.minecraft.world.entity.Entity;
import net.minecraft.world.phys.Vec3;

public class Path {
    private final List<Node> nodes;
    @Nullable
    private Path.DebugData debugData;
    private int nextNodeIndex;
    private final BlockPos target;
    private final float distToTarget;
    private final boolean reached;

    public Path(List<Node> p_77371_, BlockPos p_77372_, boolean p_77373_) {
        this.nodes = p_77371_;
        this.target = p_77372_;
        this.distToTarget = p_77371_.isEmpty() ? Float.MAX_VALUE : this.nodes.get(this.nodes.size() - 1).distanceManhattan(this.target);
        this.reached = p_77373_;
    }

    public void advance() {
        this.nextNodeIndex++;
    }

    public boolean notStarted() {
        return this.nextNodeIndex <= 0;
    }

    public boolean isDone() {
        return this.nextNodeIndex >= this.nodes.size();
    }

    @Nullable
    public Node getEndNode() {
        return !this.nodes.isEmpty() ? this.nodes.get(this.nodes.size() - 1) : null;
    }

    public Node getNode(int p_77376_) {
        return this.nodes.get(p_77376_);
    }

    public void truncateNodes(int p_77389_) {
        if (this.nodes.size() > p_77389_) {
            this.nodes.subList(p_77389_, this.nodes.size()).clear();
        }
    }

    public void replaceNode(int p_77378_, Node p_77379_) {
        this.nodes.set(p_77378_, p_77379_);
    }

    public int getNodeCount() {
        return this.nodes.size();
    }

    public int getNextNodeIndex() {
        return this.nextNodeIndex;
    }

    public void setNextNodeIndex(int p_77394_) {
        this.nextNodeIndex = p_77394_;
    }

    public Vec3 getEntityPosAtNode(Entity p_77383_, int p_77384_) {
        Node node = this.nodes.get(p_77384_);
        double d0 = node.x + (int)(p_77383_.getBbWidth() + 1.0F) * 0.5;
        double d1 = node.y;
        double d2 = node.z + (int)(p_77383_.getBbWidth() + 1.0F) * 0.5;
        return new Vec3(d0, d1, d2);
    }

    public BlockPos getNodePos(int p_77397_) {
        return this.nodes.get(p_77397_).asBlockPos();
    }

    public Vec3 getNextEntityPos(Entity p_77381_) {
        return this.getEntityPosAtNode(p_77381_, this.nextNodeIndex);
    }

    public BlockPos getNextNodePos() {
        return this.nodes.get(this.nextNodeIndex).asBlockPos();
    }

    public Node getNextNode() {
        return this.nodes.get(this.nextNodeIndex);
    }

    @Nullable
    public Node getPreviousNode() {
        return this.nextNodeIndex > 0 ? this.nodes.get(this.nextNodeIndex - 1) : null;
    }

    public boolean sameAs(@Nullable Path p_77386_) {
        if (p_77386_ == null) {
            return false;
        } else if (p_77386_.nodes.size() != this.nodes.size()) {
            return false;
        } else {
            for (int i = 0; i < this.nodes.size(); i++) {
                Node node = this.nodes.get(i);
                Node node1 = p_77386_.nodes.get(i);
                if (node.x != node1.x || node.y != node1.y || node.z != node1.z) {
                    return false;
                }
            }

            return true;
        }
    }

    public boolean canReach() {
        return this.reached;
    }

    @VisibleForDebug
    void setDebug(Node[] p_164710_, Node[] p_164711_, Set<Target> p_164712_) {
        this.debugData = new Path.DebugData(p_164710_, p_164711_, p_164712_);
    }

    @Nullable
    public Path.DebugData debugData() {
        return this.debugData;
    }

    public void writeToStream(FriendlyByteBuf p_164705_) {
        if (this.debugData != null && !this.debugData.targetNodes.isEmpty()) {
            p_164705_.writeBoolean(this.reached);
            p_164705_.writeInt(this.nextNodeIndex);
            p_164705_.writeBlockPos(this.target);
            p_164705_.writeCollection(this.nodes, (p_296986_, p_296987_) -> p_296987_.writeToStream(p_296986_));
            this.debugData.write(p_164705_);
        }
    }

    public static Path createFromStream(FriendlyByteBuf p_77391_) {
        boolean flag = p_77391_.readBoolean();
        int i = p_77391_.readInt();
        BlockPos blockpos = p_77391_.readBlockPos();
        List<Node> list = p_77391_.readList(Node::createFromStream);
        Path.DebugData path$debugdata = Path.DebugData.read(p_77391_);
        Path path = new Path(list, blockpos, flag);
        path.debugData = path$debugdata;
        path.nextNodeIndex = i;
        return path;
    }

    @Override
    public String toString() {
        return "Path(length=" + this.nodes.size() + ")";
    }

    public BlockPos getTarget() {
        return this.target;
    }

    public float getDistToTarget() {
        return this.distToTarget;
    }

    static Node[] readNodeArray(FriendlyByteBuf p_300065_) {
        Node[] anode = new Node[p_300065_.readVarInt()];

        for (int i = 0; i < anode.length; i++) {
            anode[i] = Node.createFromStream(p_300065_);
        }

        return anode;
    }

    static void writeNodeArray(FriendlyByteBuf p_300557_, Node[] p_301136_) {
        p_300557_.writeVarInt(p_301136_.length);

        for (Node node : p_301136_) {
            node.writeToStream(p_300557_);
        }
    }

    public Path copy() {
        Path path = new Path(this.nodes, this.target, this.reached);
        path.debugData = this.debugData;
        path.nextNodeIndex = this.nextNodeIndex;
        return path;
    }

    public record DebugData(Node[] openSet, Node[] closedSet, Set<Target> targetNodes) {
        public void write(FriendlyByteBuf p_299578_) {
            p_299578_.writeCollection(this.targetNodes, (p_300614_, p_300157_) -> p_300157_.writeToStream(p_300614_));
            Path.writeNodeArray(p_299578_, this.openSet);
            Path.writeNodeArray(p_299578_, this.closedSet);
        }

        public static Path.DebugData read(FriendlyByteBuf p_299429_) {
            HashSet<Target> hashset = p_299429_.readCollection(HashSet::new, Target::createFromStream);
            Node[] anode = Path.readNodeArray(p_299429_);
            Node[] anode1 = Path.readNodeArray(p_299429_);
            return new Path.DebugData(anode, anode1, hashset);
        }
    }
}