package org.bukkit.entity;

import org.bukkit.EntityEffect;
import org.bukkit.Location;
import org.bukkit.Server;
import org.bukkit.World;
import org.bukkit.event.entity.EntityDamageEvent;
import org.bukkit.event.player.PlayerTeleportEvent.TeleportCause;
import org.bukkit.metadata.Metadatable;
import org.bukkit.util.Vector;

import java.util.List;
import java.util.UUID;

/**
 * Represents a base entity in the world
 */
public interface Entity extends Metadatable
{

	/**
	 * Gets the entity's current position
	 *
	 * @return a new copy of Location containing the position of this entity
	 */
	public Location getLocation();

	/**
	 * Stores the entity's current position in the provided Location object.
	 * <p>
	 * If the provided Location is null this method does nothing and returns
	 * null.
	 *
	 * @return The Location object provided or null
	 */
	public Location getLocation(Location loc);

	/**
	 * Sets this entity's velocity
	 *
	 * @param velocity New velocity to travel with
	 */
	public void setVelocity(Vector velocity);

	/**
	 * Gets this entity's current velocity
	 *
	 * @return Current travelling velocity of this entity
	 */
	public Vector getVelocity();

	/**
	 * Returns true if the entity is supported by a block. This value is a
	 * state updated by the server and is not recalculated unless the entity
	 * moves.
	 *
	 * @return True if entity is on ground.
	 */
	public boolean isOnGround();

	/**
	 * Gets the current world this entity resides in
	 *
	 * @return World
	 */
	public World getWorld();

	/**
	 * Teleports this entity to the given location
	 *
	 * @param location New location to teleport this entity to
	 * @return <code>true</code> if the teleport was successful
	 */
	public boolean teleport(Location location);

	/**
	 * Teleports this entity to the given location
	 *
	 * @param location New location to teleport this entity to
	 * @param cause    The cause of this teleportation
	 * @return <code>true</code> if the teleport was successful
	 */
	public boolean teleport(Location location, TeleportCause cause);

	/**
	 * Teleports this entity to the target Entity
	 *
	 * @param destination Entity to teleport this entity to
	 * @return <code>true</code> if the teleport was successful
	 */
	public boolean teleport(Entity destination);

	/**
	 * Teleports this entity to the target Entity
	 *
	 * @param destination Entity to teleport this entity to
	 * @param cause       The cause of this teleportation
	 * @return <code>true</code> if the teleport was successful
	 */
	public boolean teleport(Entity destination, TeleportCause cause);

	/**
	 * Returns a list of entities within a bounding box centered around this
	 * entity
	 *
	 * @param x 1/2 the size of the box along x axis
	 * @param y 1/2 the size of the box along y axis
	 * @param z 1/2 the size of the box along z axis
	 * @return List<Entity> List of entities nearby
	 */
	public List<org.bukkit.entity.Entity> getNearbyEntities(double x, double y, double z);

	/**
	 * Returns a unique id for this entity
	 *
	 * @return Entity id
	 */
	public int getEntityId();

	/**
	 * Returns the entity's current fire ticks (ticks before the entity stops
	 * being on fire).
	 *
	 * @return int fireTicks
	 */
	public int getFireTicks();

	/**
	 * Returns the entity's maximum fire ticks.
	 *
	 * @return int maxFireTicks
	 */
	public int getMaxFireTicks();

	/**
	 * Sets the entity's current fire ticks (ticks before the entity stops
	 * being on fire).
	 *
	 * @param ticks Current ticks remaining
	 */
	public void setFireTicks(int ticks);

	/**
	 * Mark the entity's removal.
	 */
	public void remove();

	/**
	 * Returns true if this entity has been marked for removal.
	 *
	 * @return True if it is dead.
	 */
	public boolean isDead();

	/**
	 * Returns false if the entity has died or been despawned for some other
	 * reason.
	 *
	 * @return True if valid.
	 */
	public boolean isValid();

	/**
	 * Gets the {@link Server} that contains this Entity
	 *
	 * @return Server instance running this Entity
	 */
	public Server getServer();

	/**
	 * Gets the primary passenger of a vehicle. For vehicles that could have
	 * multiple passengers, this will only return the primary passenger.
	 *
	 * @return an entity
	 */
	public abstract Entity getPassenger();

	/**
	 * Set the passenger of a vehicle.
	 *
	 * @param passenger The new passenger.
	 * @return false if it could not be done for whatever reason
	 */
	public abstract boolean setPassenger(Entity passenger);

	/**
	 * Check if a vehicle has passengers.
	 *
	 * @return True if the vehicle has no passengers.
	 */
	public abstract boolean isEmpty();

	/**
	 * Eject any passenger.
	 *
	 * @return True if there was a passenger.
	 */
	public abstract boolean eject();

	/**
	 * Returns the distance this entity has fallen
	 *
	 * @return The distance.
	 */
	public float getFallDistance();

	/**
	 * Sets the fall distance for this entity
	 *
	 * @param distance The new distance.
	 */
	public void setFallDistance(float distance);

	/**
	 * Record the last {@link EntityDamageEvent} inflicted on this entity
	 *
	 * @param event a {@link EntityDamageEvent}
	 */
	public void setLastDamageCause(EntityDamageEvent event);

	/**
	 * Retrieve the last {@link EntityDamageEvent} inflicted on this entity.
	 * This event may have been cancelled.
	 *
	 * @return the last known {@link EntityDamageEvent} or null if hitherto
	 * unharmed
	 */
	public EntityDamageEvent getLastDamageCause();

	/**
	 * Returns a unique and persistent id for this entity
	 *
	 * @return unique id
	 */
	public UUID getUniqueId();

	/**
	 * Gets the amount of ticks this entity has lived for.
	 * <p>
	 * This is the equivalent to "age" in entities.
	 *
	 * @return Age of entity
	 */
	public int getTicksLived();

	/**
	 * Sets the amount of ticks this entity has lived for.
	 * <p>
	 * This is the equivalent to "age" in entities. May not be less than one
	 * tick.
	 *
	 * @param value Age of entity
	 */
	public void setTicksLived(int value);

	/**
	 * Performs the specified {@link EntityEffect} for this entity.
	 * <p>
	 * This will be viewable to all players near the entity.
	 *
	 * @param type Effect to play.
	 */
	public void playEffect(EntityEffect type);

	/**
	 * Get the type of the entity.
	 *
	 * @return The entity type.
	 */
	public EntityType getType();

	/**
	 * Returns whether this entity is inside a vehicle.
	 *
	 * @return True if the entity is in a vehicle.
	 */
	public boolean isInsideVehicle();

	/**
	 * Leave the current vehicle. If the entity is currently in a vehicle (and
	 * is removed from it), true will be returned, otherwise false will be
	 * returned.
	 *
	 * @return True if the entity was in a vehicle.
	 */
	public boolean leaveVehicle();

	/**
	 * Get the vehicle that this player is inside. If there is no vehicle,
	 * null will be returned.
	 *
	 * @return The current vehicle.
	 */
	public Entity getVehicle();

	// Spigot Start
	public class Spigot
	{

		/**
		 * Returns whether this entity is invulnerable.
		 *
		 * @return True if the entity is invulnerable.
		 */
		public boolean isInvulnerable()
		{
			throw new UnsupportedOperationException("Not supported yet.");
		}
	}

	Spigot spigot();
	// Spigot End
}