package redis.clients.jedis;

import redis.clients.jedis.exceptions.JedisAskDataException;
import redis.clients.jedis.exceptions.JedisClusterException;
import redis.clients.jedis.exceptions.JedisClusterMaxRedirectionsException;
import redis.clients.jedis.exceptions.JedisRedirectionException;
import redis.clients.util.JedisClusterCRC16;

public abstract class JedisClusterCommand<T> {
	
	private boolean asking = false;
	
	private JedisClusterConnectionHandler connectionHandler;
	private int commandTimeout;
	private int redirections;
//	private boolean asking = false;
	
	public JedisClusterCommand(JedisClusterConnectionHandler connectionHandler, int timeout, int maxRedirections) {
		this.connectionHandler = connectionHandler;
		this.commandTimeout = timeout;
		this.redirections = maxRedirections;
	}

	public abstract T execute();
	
	public T run(String key) {
		try {
			
			if (key == null) {
				throw new JedisClusterException("No way to dispatch this command to Redis Cluster.");
			} else if (redirections == 0) {
				throw new JedisClusterMaxRedirectionsException("Too many Cluster redirections?");
			}
			connectionHandler.getConnectionFromSlot(JedisClusterCRC16.getSlot(key));
			if (asking) {
				//TODO: Pipeline asking with the original command to make it faster....
				connectionHandler.getConnection().asking();
			}
			return execute();
		} catch (JedisRedirectionException jre) {
			return handleRedirection(jre, key);
		}
	}

	private T handleRedirection(JedisRedirectionException jre, String key) {
		if (jre instanceof JedisAskDataException) {
			asking = true;
		}
		redirections--;
		this.connectionHandler.assignSlotToNode(jre.getSlot(), jre.getTargetNode());
		return run(key);
	}
}