/*
* MegaMek - Copyright (C) 2003 Ben Mazur (bmazur@sev.org)
*
* This program 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.
*
* This program 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.
*/
package megamek.common.xml;
import gd.xml.tiny.ParsedXML;
import java.io.IOException;
import java.io.Writer;
import java.util.Enumeration;
import megamek.common.Entity;
import megamek.common.IGame;
import megamek.common.Tank;
/**
* Objects of this class can encode a <code>Entity</code> object as XML into
* an output writer and decode one from a parsed XML node. It is used when
* saving games into a version- neutral format.
*
* @author James Damour <suvarov454@users.sourceforge.net>
*/
public class TankEncoder {
/**
* Encode a <code>Entity</code> object to an output writer.
*
* @param entity - the <code>Entity</code> to be encoded. This value must
* not be <code>null</code>.
* @param out - the <code>Writer</code> that will receive the XML. This
* value must not be <code>null</code>.
* @throws <code>IllegalArgumentException</code> if the entity is
* <code>null</code>.
* @throws <code>IOException</code> if there's any error on write.
*/
public static void encode(Entity entity, Writer out) throws IOException {
Tank tank = (Tank) entity;
int value;
// First, validate our input.
if (null == entity) {
throw new IllegalArgumentException("The entity is null.");
}
if (null == out) {
throw new IllegalArgumentException("The writer is null.");
}
// Our EntityEncoder already gave us our root element.
out.write("<hasNoTurret value=\"");
out.write(tank.hasNoTurret() ? "true" : "false");
out.write("\" /><stunnedTurns value=\"");
value = tank.getStunnedTurns();
out.write(String.valueOf(value));
out.write("\" /><moveHit value=\"");
out.write(tank.isMovementHit() ? "true" : "false");
out.write("\" /><moveHitPending value=\"");
out.write(tank.isMovementHitPending() ? "true" : "false");
// Is the turret locked?
if (tank.isTurretLocked()) {
// Yup. Record the current facing of the tank and the turret.
out.write("\" /><facing value=\"");
value = tank.getFacing();
out.write(String.valueOf(value));
out.write("\" /><turretFacing value=\"");
value = tank.getSecondaryFacing();
out.write(String.valueOf(value));
out.write("\" /><turretLocked value=\"true");
}
out.write("\" />");
}
/**
* Decode a <code>Entity</code> object from the passed node.
*
* @param node - the <code>ParsedXML</code> node for this object. This
* value must not be <code>null</code>.
* @param game - the <code>IGame</code> the decoded object belongs to.
* @return the <code>Entity</code> object based on the node.
* @throws <code>IllegalArgumentException</code> if the node is
* <code>null</code>.
* @throws <code>IllegalStateException</code> if the node does not contain
* a valid <code>Entity</code>.
*/
public static Entity decode(ParsedXML node, IGame game) {
Tank entity = null;
String attrStr;
int attrVal;
// Did we get a null node?
if (null == node) {
throw new IllegalArgumentException("The Tank node is null.");
}
// Make sure that the node is for an Tank unit.
attrStr = node.getAttribute("name");
if (!node.getName().equals("class") || null == attrStr
|| !attrStr.equals("Tank")) {
throw new IllegalStateException("Not passed an Tank node.");
}
// TODO : perform version checking.
// Create the entity.
entity = new Tank();
// Walk the board node's children.
Enumeration<?> children = node.elements();
while (children.hasMoreElements()) {
ParsedXML child = (ParsedXML) children.nextElement();
String childName = child.getName();
// Handle null child names.
if (null == childName) {
// No-op.
}
// Did we find the stunnedTurns node?
else if (childName.equals("stunnedTurns")) {
// Get the Tank's stunned turns.
attrStr = child.getAttribute("value");
if (null == attrStr) {
throw new IllegalStateException(
"Couldn't decode the stunnedTurns for a Tank unit.");
}
// Try to pull the number from the attribute string
try {
attrVal = Integer.parseInt(attrStr);
} catch (NumberFormatException exp) {
throw new IllegalStateException(
"Couldn't get an integer from " + attrStr);
}
entity.setStunnedTurns(attrVal);
}
// Did we find the hasNoTurret node?
else if (childName.equals("hasNoTurret")) {
// See if the Tank has a no turret.
attrStr = child.getAttribute("value");
if (null == attrStr) {
throw new IllegalStateException(
"Couldn't decode hasNoTurret for a Tank unit.");
}
// If the value is "true", the Tank has a no turret.
if (attrStr.equals("true")) {
entity.setHasNoTurret(true);
} else {
entity.setHasNoTurret(false);
}
}
// Did we find the moveHit node?
else if (childName.equals("moveHit")) {
// See if the Tank has a move hit.
attrStr = child.getAttribute("value");
if (null == attrStr) {
throw new IllegalStateException(
"Couldn't decode moveHit for a Tank unit.");
}
// If the value is "true", the Tank move a hit pending.
if (attrStr.equals("true")) {
entity.immobilize();
entity.applyDamage();
}
}
// Did we find the moveHitPending node?
else if (childName.equals("moveHitPending")) {
// See if the Tank has a move hit pending.
attrStr = child.getAttribute("value");
if (null == attrStr) {
throw new IllegalStateException(
"Couldn't decode moveHitPending for a Tank unit.");
}
// If the value is "true", the Tank move a hit pending.
if (attrStr.equals("true")) {
entity.immobilize();
}
}
// Did we find the facing node?
else if (childName.equals("facing")) {
// Get the Tank's facing.
attrStr = child.getAttribute("value");
if (null == attrStr) {
throw new IllegalStateException(
"Couldn't decode the facing for a Tank unit.");
}
// Try to pull the number from the attribute string
try {
attrVal = Integer.parseInt(attrStr);
} catch (NumberFormatException exp) {
throw new IllegalStateException(
"Couldn't get an integer from " + attrStr);
}
entity.setFacing(attrVal);
}
// Did we find the turret's secondaryFacing node?
else if (childName.equals("turretFacing")) {
// Get the Tank's turret's facing.
attrStr = child.getAttribute("value");
if (null == attrStr) {
throw new IllegalStateException(
"Couldn't decode the turret's secondaryFacing for a Tank unit.");
}
// Try to pull the number from the attribute string
try {
attrVal = Integer.parseInt(attrStr);
} catch (NumberFormatException exp) {
throw new IllegalStateException(
"Couldn't get an integer from " + attrStr);
}
entity.setSecondaryFacing(attrVal);
}
// Did we find the turretLocked node?
else if (childName.equals("turretLocked")) {
// See if the Tank move a hit pending.
attrStr = child.getAttribute("value");
if (null == attrStr) {
throw new IllegalStateException(
"Couldn't decode turretLocked for a Tank unit.");
}
// If the value is "true", the Tank move a hit pending.
if (attrStr.equals("true")) {
entity.lockTurret();
}
}
} // Handle the next element.
// Return the entity.
return entity;
}
}