LandMountController.java

import com.comphenix.protocol.PacketType;
import com.comphenix.protocol.ProtocolLibrary;
import com.comphenix.protocol.ProtocolManager;
import com.comphenix.protocol.events.ListenerPriority;
import com.comphenix.protocol.events.PacketAdapter;
import com.comphenix.protocol.events.PacketEvent;
import net.runeage.simplesteeds.objects.SteedAttributes;
import net.runeage.simplesteeds.objects.SteedType;
import net.runeage.simplesteeds.objects.WrapperPlayClientSteerVehicle;
import net.runeage.simplesteeds.util.ControllerUtil;
import net.runeage.simplesteeds.util.SteedUtil;
import org.bukkit.Location;
import org.bukkit.block.Block;
import org.bukkit.block.BlockFace;
import org.bukkit.entity.Entity;
import org.bukkit.entity.EntityType;
import org.bukkit.entity.LivingEntity;
import org.bukkit.entity.Player;
import org.bukkit.plugin.java.JavaPlugin;
import org.bukkit.util.Vector;

import java.util.List;

public class LandMountController {

    List<EntityType> ignoredMobTypes = List.of(EntityType.HORSE, EntityType.SKELETON_HORSE, EntityType.ZOMBIE_HORSE);

    public LandMountController(JavaPlugin plugin) {
        ProtocolManager manager = ProtocolLibrary.getProtocolManager();
        manager.addPacketListener(getPacketAdapter(plugin));
    }

    private PacketAdapter getPacketAdapter(JavaPlugin plugin) {
        return new PacketAdapter(plugin, ListenerPriority.NORMAL, PacketType.Play.Client.STEER_VEHICLE) {
            @Override
            public void onPacketReceiving(PacketEvent event) {
                if (event.getPacketType() != PacketType.Play.Client.STEER_VEHICLE) return;
                Player player = event.getPlayer();
                WrapperPlayClientSteerVehicle packet = new WrapperPlayClientSteerVehicle(event.getPacket());
                Entity vehicle = player.getVehicle();
                if (vehicle == null) return;
                if (!(vehicle instanceof LivingEntity)) return;
                if (!SteedUtil.isSteed(vehicle)) return;
                if (SteedUtil.getSteedType(vehicle) != SteedType.LAND) return;
                if (packet.isUnmount()) {
                    vehicle.addScoreboardTag("EJECT");
                    return;
                }
                if (ignoredMobTypes.contains(vehicle.getType())) return;

                if (isRunningIntoJumpableBlock((LivingEntity) vehicle) && vehicle.isOnGround()) {
                    ((LivingEntity) vehicle).setJumping(true);
                    return;
                }

                SteedAttributes attributes = new SteedAttributes((LivingEntity) vehicle);
                if (packet.isJump() && vehicle.isOnGround()) {
                    vehicle.setVelocity(vehicle.getVelocity().add(new Vector(0.0, attributes.getCurrentJump(), 0.0)));
                }

                Vector vel = ControllerUtil.getVelocityVector(vehicle.getVelocity(), player, packet.getForward(),
                        packet.getSideways(), attributes.getCurrentSpeed());
                vehicle.setVelocity(vel);
                vehicle.setRotation(player.getEyeLocation().getYaw(), player.getEyeLocation().getPitch());
            }
        };
    }

    private boolean isRunningIntoJumpableBlock(LivingEntity vehicle) {
        Location eyeLocation = vehicle.getEyeLocation();
        eyeLocation.setPitch(0);
        Vector lookVector = eyeLocation.getDirection().clone();
        Location checkLoc = vehicle.getLocation().add(lookVector.clone());
        Block block = checkLoc.getBlock();
        Block above = block.getRelative(BlockFace.UP);
        Block aboveAbove = above.getRelative(BlockFace.UP);
        return !block.isPassable() && (above.isPassable() && aboveAbove.isPassable());
    }

}