/**
 * Copyright 2007-2016, Kaazing Corporation. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.mina.integration.beans;

import java.beans.PropertyEditor;
import java.util.regex.Pattern;

/**
 * A {@link PropertyEditor} which converts a {@link String} into
 * a {@link Number} and vice versa.
 *
 * @author <a href="http://mina.apache.org">Apache MINA Project</a>
 */
public class NumberEditor extends AbstractPropertyEditor {
    private static final Pattern DECIMAL = Pattern.compile(
            "[-+]?[0-9]*\\.?[0-9]*(?:[Ee][-+]?[0-9]+)?");
    private static final Pattern HEXADECIMAL = Pattern.compile("0x[0-9a-fA-F]+");
    private static final Pattern OCTET = Pattern.compile("0[0-9][0-9]*");
    
    @Override
    protected final String toText(Object value) {
        return value.toString();
    }

    @Override
    protected final Object toValue(String text) throws IllegalArgumentException {
        if (text.length() == 0) {
            return defaultValue();
        }
        
        if (HEXADECIMAL.matcher(text).matches()) {
            return toValue(text.substring(2), 16);
        }
        
        if (OCTET.matcher(text).matches()) {
            return toValue(text, 8);
        }
        
        if (DECIMAL.matcher(text).matches()) {
            return toValue(text, 10);
        }
        
        throw new NumberFormatException("Not a number: " + text);
    }
    
    protected Object toValue(String text, int radix) {
        return Integer.parseInt(text, radix);
    }
    
    @Override
    protected Object defaultValue() {
        return 0;
    }
}
