/**
* Copyright (C) 2010 dennis zhuang (killme2008@gmail.com)
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
**/
package com.googlecode.aviator.runtime.type;
import java.util.Collections;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import com.googlecode.aviator.exception.ExpressionRuntimeException;
/**
* A Aviator regular expression pattern
*
* @author dennis
*
*/
public class AviatorPattern extends AviatorObject {
final Pattern pattern;
public AviatorPattern(String expression) {
super();
this.pattern = Pattern.compile(expression);
}
public Pattern getPattern() {
return pattern;
}
@Override
public AviatorObject add(AviatorObject other, Map<String, Object> env) {
switch (other.getAviatorType()) {
case String:
return new AviatorString(this.pattern.pattern() + ((AviatorString) other).lexeme);
case JavaType:
AviatorJavaType javaType = (AviatorJavaType) other;
final Object otherValue = javaType.getValue(env);
if (otherValue instanceof String || otherValue instanceof Character) {
return new AviatorString(this.pattern.pattern() + otherValue.toString());
}
else {
return super.add(other, env);
}
default:
return super.add(other, env);
}
}
@Override
public AviatorObject match(AviatorObject other, Map<String, Object> env) {
switch (other.getAviatorType()) {
case String:
AviatorString aviatorString = (AviatorString) other;
Matcher m = this.pattern.matcher(aviatorString.lexeme);
if (m.matches()) {
if (env != null && env != Collections.EMPTY_MAP) {
int groupCount = m.groupCount();
for (int i = 0; i <= groupCount; i++) {
env.put("$" + i, m.group(i));
}
}
return AviatorBoolean.TRUE;
}
else {
return AviatorBoolean.FALSE;
}
case JavaType:
AviatorJavaType javaType = (AviatorJavaType) other;
final Object javaValue = javaType.getValue(env);
if (javaValue instanceof String) {
return match(new AviatorString((String) javaValue), env);
}
else if (javaValue instanceof Character) {
return match(new AviatorString(String.valueOf(javaValue)), env);
}
else {
throw new ExpressionRuntimeException(this.desc(env) + " could not match " + other.desc(env));
}
default:
throw new ExpressionRuntimeException(this.desc(env) + " could not match " + other.desc(env));
}
}
@Override
public int compare(AviatorObject other, Map<String, Object> env) {
switch (other.getAviatorType()) {
case Pattern:
return this.pattern.pattern().compareTo(((AviatorPattern) other).pattern.pattern());
case JavaType:
if (other.getValue(env) == null) {
return 1;
}
else {
throw new ExpressionRuntimeException("Could not compare Pattern with " + other.getAviatorType());
}
case Nil:
return 1;
default:
throw new ExpressionRuntimeException("Could not compare Pattern with " + other.getAviatorType());
}
}
@Override
public AviatorType getAviatorType() {
return AviatorType.Pattern;
}
@Override
public Object getValue(Map<String, Object> env) {
return "/" + pattern.pattern() + "/";
}
}