package eu.univento.core.api.events;

import org.bukkit.Location;
import org.bukkit.Server;
import org.bukkit.World;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.player.PlayerMoveEvent;

import java.util.WeakHashMap;

/**
 * @author Crislibaer
 */
public class MoveEventFilter implements Listener
{
    public static class PlayerBlockMoveEvent extends PlayerMoveEvent
    {
        public PlayerBlockMoveEvent(PlayerMoveEvent pEvent)
        {
            super(pEvent.getPlayer(), pEvent.getFrom(), pEvent.getTo());
        }
    }

    private static class BlockPosition
    {
        public int x;
        public int y;
        public int z;
        public World world;
    }

    private Server mServer;
    private WeakHashMap<Player, BlockPosition> mLastPosition = new WeakHashMap<>();

    public MoveEventFilter(Server pServer)
    {
        mServer = pServer;
    }

    @EventHandler
    public void onPlayerMove(PlayerMoveEvent pEvent)
    {
        if(pEvent.isCancelled() || pEvent instanceof PlayerBlockMoveEvent)
        {
            return;
        }

        BlockPosition lastPos = mLastPosition.get(pEvent.getPlayer());
        Location currentPos = pEvent.getTo();
        boolean fireEvent = false;

        if(lastPos == null)
        {
            lastPos = new BlockPosition();
            mLastPosition.put(pEvent.getPlayer(), lastPos);
            fireEvent = true;
        }
        else if(lastPos.x != currentPos.getBlockX() || lastPos.z != currentPos.getBlockZ() || lastPos.y != currentPos.getBlockY())
        {
            fireEvent = true;
        }
        else if(lastPos.world != currentPos.getWorld())
        {
            fireEvent = true;
        }

        if(fireEvent)
        {
            // make sure that our event is synchronous
            assert !pEvent.isAsynchronous();

            // fire event
            PlayerBlockMoveEvent event = new PlayerBlockMoveEvent(pEvent);
            mServer.getPluginManager().callEvent(event);

            // check event state and only update new position if event does not gets canceled
            if(!event.isCancelled())
            {
                // update new position
                lastPos.world = currentPos.getWorld();
                lastPos.x = currentPos.getBlockX();
                lastPos.y = currentPos.getBlockY();
                lastPos.z = currentPos.getBlockZ();
            }
        }
    }
}