/**
* 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
* MERCHANTLIMIT 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.model;
import org.freecolandroid.xml.stream.XMLStreamException;
import org.freecolandroid.xml.stream.XMLStreamReader;
import org.freecolandroid.xml.stream.XMLStreamWriter;
import net.sf.freecol.common.model.Operand.OperandType;
/**
* The <code>Limit</code> class encapsulates a limit on the
* availability of FreeColObjects. It consists of a left hand side, an
* operator and a right hand side, and can be used to limit the number
* of units of a particular type (e.g. wagon trains) to the number of
* a player's colonies, for example. The left hand side must apply to
* the object on which a limit is to be placed.
*/
public final class Limit extends FreeColGameObjectType {
public static enum Operator {
EQ, LT, GT, LE, GE
}
/**
* Describe operator here.
*/
private Operator operator;
/**
* Describe leftHandSide here.
*/
private Operand leftHandSide;
/**
* Describe rightHandSide here.
*/
private Operand rightHandSide;
public Limit(Specification specification) {
super(specification);
}
public Limit(String id, Operand lhs, Operator op, Operand rhs) {
setId(id);
leftHandSide = lhs;
rightHandSide = rhs;
operator = op;
}
/**
* Get the <code>Operator</code> value.
*
* @return an <code>Operator</code> value
*/
public Operator getOperator() {
return operator;
}
/**
* Set the <code>Operator</code> value.
*
* @param newOperator The new Operator value.
*/
public void setOperator(final Operator newOperator) {
this.operator = newOperator;
}
/**
* Get the <code>LeftHandSide</code> value.
*
* @return an <code>Operand</code> value
*/
public Operand getLeftHandSide() {
return leftHandSide;
}
/**
* Set the <code>LeftHandSide</code> value.
*
* @param newLeftHandSide The new LeftHandSide value.
*/
public void setLeftHandSide(final Operand newLeftHandSide) {
this.leftHandSide = newLeftHandSide;
}
/**
* Get the <code>RightHandSide</code> value.
*
* @return an <code>Operand</code> value
*/
public Operand getRightHandSide() {
return rightHandSide;
}
/**
* Set the <code>RightHandSide</code> value.
*
* @param newRightHandSide The new RightHandSide value.
*/
public void setRightHandSide(final Operand newRightHandSide) {
this.rightHandSide = newRightHandSide;
}
public boolean appliesTo(FreeColObject object) {
return leftHandSide.appliesTo(object);
}
/**
* Describe <code>evaluate</code> method here.
*
* @param game a <code>Game</code> value
* @return a <code>boolean</code> value
*/
public boolean evaluate(Game game) {
Integer lhs = null;
switch(leftHandSide.getScopeLevel()) {
case GAME:
lhs = leftHandSide.getValue(game);
break;
default:
lhs = leftHandSide.getValue();
}
Integer rhs = null;
switch(rightHandSide.getScopeLevel()) {
case GAME:
rhs = rightHandSide.getValue(game);
break;
default:
rhs = rightHandSide.getValue();
}
return evaluate(lhs, rhs);
}
/**
* Describe <code>evaluate</code> method here.
*
* @param player a <code>Player</code> value
* @return a <code>boolean</code> value
*/
public boolean evaluate(Player player) {
Integer lhs = null;
switch(leftHandSide.getScopeLevel()) {
case PLAYER:
lhs = leftHandSide.getValue(player);
break;
case GAME:
lhs = leftHandSide.getValue(player.getGame());
break;
default:
lhs = leftHandSide.getValue();
}
Integer rhs = null;
switch(rightHandSide.getScopeLevel()) {
case PLAYER:
rhs = rightHandSide.getValue(player);
break;
case GAME:
rhs = rightHandSide.getValue(player.getGame());
break;
default:
rhs = rightHandSide.getValue();
}
return evaluate(lhs, rhs);
}
/**
* Describe <code>evaluate</code> method here.
*
* @param settlement a <code>Settlement</code> value
* @return a <code>boolean</code> value
*/
public boolean evaluate(Settlement settlement) {
Integer lhs = null;
switch(leftHandSide.getScopeLevel()) {
case SETTLEMENT:
lhs = leftHandSide.getValue(settlement);
lhs += getSpecification()
.getIntegerOption("model.option.settlementLimitModifier")
.getValue();
break;
case PLAYER:
lhs = leftHandSide.getValue(settlement.getOwner());
break;
case GAME:
lhs = leftHandSide.getValue(settlement.getGame());
break;
default:
lhs = leftHandSide.getValue();
}
Integer rhs = null;
switch(rightHandSide.getScopeLevel()) {
case SETTLEMENT:
rhs = rightHandSide.getValue(settlement);
break;
case PLAYER:
rhs = rightHandSide.getValue(settlement.getOwner());
break;
case GAME:
rhs = rightHandSide.getValue(settlement.getGame());
break;
default:
rhs = rightHandSide.getValue();
}
return evaluate(lhs, rhs);
}
/**
* Returns true if at least one of the Operands has the given
* OperandType.
*
* @param type an <code>OperandType</code> value
* @return a <code>boolean</code> value
*/
public boolean hasOperandType(OperandType type) {
return leftHandSide.getOperandType() == type
|| rightHandSide.getOperandType() == type;
}
private boolean evaluate(Integer lhs, Integer rhs) {
if (lhs == null || rhs == null) {
return true;
}
switch(operator) {
case EQ: return lhs == rhs;
case LT: return lhs < rhs;
case GT: return lhs > rhs;
case LE: return lhs <= rhs;
case GE: return lhs >= rhs;
default: return false;
}
}
/**
* This method writes an XML-representation of this object to
* the given stream.
*
* @param out The target stream.
* @throws XMLStreamException if there are any problems writing
* to the stream.
*/
public void toXMLImpl(XMLStreamWriter out) throws XMLStreamException {
super.toXML(out, getXMLElementTagName());
}
/**
* Write the attributes of this object to a stream.
*
* @param out The target stream.
* @throws XMLStreamException if there are any problems writing to
* the stream.
*/
@Override
protected void writeAttributes(XMLStreamWriter out)
throws XMLStreamException {
super.writeAttributes(out);
out.writeAttribute("operator", operator.toString());
}
/**
* Write the children of this object to a stream.
*
* @param out The target stream.
* @throws XMLStreamException if there are any problems writing to
* the stream.
*/
@Override
protected void writeChildren(XMLStreamWriter out)
throws XMLStreamException {
super.writeChildren(out);
leftHandSide.toXML(out, "leftHandSide");
rightHandSide.toXML(out, "rightHandSide");
}
/**
* Reads the attributes of this object from an XML stream.
*
* @param in The XML input stream.
* @exception XMLStreamException if a problem was encountered
* during parsing.
*/
@Override
protected void readAttributes(XMLStreamReader in)
throws XMLStreamException {
super.readAttributes(in);
operator = Enum.valueOf(Operator.class,
in.getAttributeValue(null, "operator"));
}
/**
* Reads a child object.
*
* @param in The XML stream to read.
* @exception XMLStreamException if an error occurs
*/
@Override
protected void readChild(XMLStreamReader in) throws XMLStreamException {
String childName = in.getLocalName();
if ("leftHandSide".equals(childName)) {
leftHandSide = new Operand();
leftHandSide.readFromXMLImpl(in);
} else if ("rightHandSide".equals(childName)) {
rightHandSide = new Operand();
rightHandSide.readFromXMLImpl(in);
} else {
logger.warning("Unsupported child element: " + childName);
}
}
public String toString() {
return leftHandSide.toString() + " " + operator.toString() + " "
+ rightHandSide.toString();
}
/**
* Returns the XML tag name for this element.
*
* @return "limit".
*/
public static String getXMLElementTagName() {
return "limit";
}
}