/**
* Copyright (C) 2002-2012 The FreeCol Team
*
* This file is part of FreeCol.
*
* FreeCol is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* FreeCol is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with FreeCol. If not, see <http://www.gnu.org/licenses/>.
*/
package net.sf.freecol.common.networking;
import net.sf.freecol.common.model.FreeColGameObject;
import net.sf.freecol.common.model.Game;
import net.sf.freecol.common.model.Location;
import net.sf.freecol.common.model.Map.Direction;
import net.sf.freecol.common.model.Tile;
import net.sf.freecol.common.model.Unit;
import net.sf.freecol.common.model.Player;
import net.sf.freecol.server.FreeColServer;
import net.sf.freecol.server.model.ServerPlayer;
import org.w3c.dom.Element;
/**
* The message sent when embarking.
*/
public class EmbarkMessage extends DOMMessage {
/**
* The id of the unit embarking.
*/
private String unitId;
/**
* The id of the carrier to embark onto.
*/
private String carrierId;
/**
* An optional direction for the unit to move to find the carrier.
*/
private String directionString;
/**
* Create a new <code>EmbarkMessage</code> with the
* supplied unit, carrier and optional direction.
*
* @param unit The <code>Unit</code> to embark.
* @param carrier The carrier <code>Unit</code> to embark on.
* @param direction An option direction to embark in.
*/
public EmbarkMessage(Unit unit, Unit carrier, Direction direction) {
this.unitId = unit.getId();
this.carrierId = carrier.getId();
this.directionString = (direction == null) ? null
: String.valueOf(direction);
}
/**
* Create a new <code>EmbarkMessage</code> from a
* supplied element.
*
* @param game The <code>Game</code> this message belongs to.
* @param element The <code>Element</code> to use to create the message.
*/
public EmbarkMessage(Game game, Element element) {
this.unitId = element.getAttribute("unit");
this.carrierId = element.getAttribute("carrier");
this.directionString = (!element.hasAttribute("direction")) ? null
: element.getAttribute("direction");
}
/**
* Handle a "embark"-message.
*
* @param server The <code>FreeColServer</code> handling the message.
* @param player The <code>Player</code> the message applies to.
* @param connection The <code>Connection</code> message was received on.
* @return An update containing the embarked unit,
* or an error <code>Element</code> on failure.
*/
public Element handle(FreeColServer server, Player player,
Connection connection) {
ServerPlayer serverPlayer = server.getPlayer(connection);
Unit unit;
try {
unit = server.getUnitSafely(unitId, serverPlayer);
} catch (Exception e) {
return DOMMessage.clientError(e.getMessage());
}
Unit carrier;
try {
carrier = server.getUnitSafely(carrierId, serverPlayer);
} catch (Exception e) {
return DOMMessage.clientError(e.getMessage());
}
Location sourceLocation = unit.getLocation();
Tile sourceTile = null;
Tile destinationTile = null;
Direction direction;
if (directionString == null) {
// Locations must be the same, or the source is also a
// carrier in the same location as the carrier, or they
// must be on the same tile.
if (sourceLocation == carrier.getLocation()
|| ((sourceLocation instanceof Unit)
&& ((Unit) sourceLocation).getLocation()
== carrier.getLocation())
|| (sourceLocation.getTile() != null
&& sourceLocation.getTile() == carrier.getTile())) {
direction = null;
} else {
return DOMMessage.clientError("Unit " + unitId
+ " at " + ((FreeColGameObject) sourceLocation)
+ " and carrier " + carrierId
+ " at " + ((FreeColGameObject) carrier.getLocation())
+ " are not co-located.");
}
} else {
// Units have to be on the map and have moves left if a
// move is involved.
try {
direction = Enum.valueOf(Direction.class, directionString);
} catch (Exception e) {
return DOMMessage.clientError(e.getMessage());
}
sourceTile = unit.getTile();
if (sourceTile == null) {
return DOMMessage.clientError("Unit is not on the map: "
+ unitId);
}
if (unit.getMovesLeft() <= 0) {
return DOMMessage.clientError("Unit has no moves left: "
+ unitId);
}
destinationTile = sourceTile.getNeighbourOrNull(direction);
if (destinationTile == null) {
return DOMMessage.clientError("Could not find tile"
+ " in direction: " + direction + " from unit: " + unitId);
}
if (carrier.getTile() != destinationTile) {
return DOMMessage.clientError("Carrier: " + carrierId
+ " is not at destination tile: "
+ destinationTile.toString());
}
}
// Proceed to embark
return server.getInGameController()
.embarkUnit(serverPlayer, unit, carrier);
}
/**
* Convert this EmbarkMessage to XML.
*
* @return The XML representation of this message.
*/
public Element toXMLElement() {
Element result = createNewRootElement(getXMLElementTagName());
result.setAttribute("unit", unitId);
result.setAttribute("carrier", carrierId);
if (directionString != null) {
result.setAttribute("direction", directionString);
}
return result;
}
/**
* The tag name of the root element representing this object.
*
* @return "embark".
*/
public static String getXMLElementTagName() {
return "embark";
}
}