package jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.impl.logger;

import java.nio.ByteBuffer;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.operations.DeleteAttributeOperation;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.operations.NodeOperation;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.operations.PutAttributeOperation;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.trasnformer.EditableAttributes;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.trasnformer.EditableNode;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.util.DefaultEither;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.util.Either;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.util.Error;

public class LoggingAttributes<T extends EditableNode<T>> implements EditableAttributes<LoggingNode<T>>
{
	private final T wrap;
	private final OperationLog log;
	
	public LoggingAttributes(T _wrap,OperationLog _log)
	{
		wrap = _wrap;
		log = _log;
	}

	@Override
	public ByteBuffer get(String _key)
	{
		EditableAttributes<T> attributes = wrap.getAttributes();
		return attributes.get(_key);
	}
	
	private Either<Error,LoggingNode<T>> edit(NodeOperation _op)
	{
		Either<Error,T> either = _op.invoke(wrap);
		if(either.isA()){
			return DefaultEither.newA(either.a());
		}
		
		T newWrap = either.b();
		OperationLog newLog = log.add(_op);
		LoggingNode<T> newLoggingNode = new LoggingNode<T>(newWrap,newLog);
		
		return DefaultEither.newB(newLoggingNode);
	}

	@Override
	public Either<Error,LoggingNode<T>> delete(final String _key)
	{
		
		DeleteAttributeOperation deleteAttribute = new DeleteAttributeOperation(_key);
		return edit(deleteAttribute);
	}

	@Override
	public Either<Error,LoggingNode<T>> put(final String _key,final ByteBuffer _value)
	{
		PutAttributeOperation putAttribute = new PutAttributeOperation(_key,_value);
		return edit(putAttribute);
	}
}