/**
 *
 */
package com.jotuntech.sketcher.client.command;

import java.awt.AlphaComposite;
import java.nio.ByteBuffer;

import com.jotuntech.sketcher.client.Client;
import com.jotuntech.sketcher.client.Command;
import com.jotuntech.sketcher.client.Connection;
import com.jotuntech.sketcher.common.Input;
import com.jotuntech.sketcher.common.Layer;
import com.jotuntech.sketcher.common.User;


public class LineCommand implements Command {
	protected Input input;

	/** Constructs a Daub command */
	public LineCommand() {

	}

	/** Constructs a Daub command.
	 * @param user Source user.
	 * @param input Position of new daub. */
	public LineCommand(Input input) {
		this.input = input;
	}

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

			Layer l = user.getPhantomLayer();
			l.setOpacity(Math.abs(user.getBrush().getOpacity()) / 255f);
			if(user.getBrush().isLockTransparency()) {
				l.setAlphaRule(AlphaComposite.SRC_ATOP);
			} else if(user.getBrush().getOpacity() >= 0) {
				l.setAlphaRule(AlphaComposite.SRC_OVER);
			} else {
				l.setAlphaRule(AlphaComposite.DST_OUT);
			}

			/** Draw line */
			Input end = user.getPhantomLayer().line(user.getCursor(), input, user.getColor(), user.getBrush(), user.getLayer());

			if(end != null) {
				/** Move cursor on success */
				user.setCursor(end);

				/** Return and broadcast */
				return Connection.SEND_OTHERS;
			}
		}

		/** Return silently */
		return Connection.SEND_NONE;
	}

	public void decode(ByteBuffer in) {
		input = new Input();
		input.decode(in);
	}

	public void encode(ByteBuffer out) {
		input.encode(out);
	}
}