package com.jotuntech.sketcher.client.command;

import java.nio.ByteBuffer;

import com.jotuntech.sketcher.client.Client;
import com.jotuntech.sketcher.client.Command;
import com.jotuntech.sketcher.common.BitmapUndoData;
import com.jotuntech.sketcher.common.Layer;
import com.jotuntech.sketcher.common.UndoEntry;
import com.jotuntech.sketcher.common.User;
import com.jotuntech.sketcher.server.Connection;

public class UndoEntryCommand implements Command {
	Integer layerKey;

	public int perform(Client client, User user) {
		if(user == null) {
			return Connection.SEND_NONE;
		}

		if(user.isViewer()) {
			return Connection.SEND_NONE;
		}

		Layer layer = client.getCanvas().getLayerMap().get(layerKey);

		if(layer == null) {
			return Connection.SEND_NONE;
		}

		UndoEntry undoEntry = new UndoEntry();
		undoEntry.setLayer(layer);
		undoEntry.setUndoData(new BitmapUndoData());
		user.getUndoDeque().addLast(undoEntry);

		return Connection.SEND_NONE;
	}

	public void decode(ByteBuffer in) {
		layerKey = in.getInt();
	}

	public void encode(ByteBuffer out) {
		out.putInt(layerKey);
	}
}