/*
 * Copyright (c) 2002-2015, JIDE Software Inc. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 */
package jidefx.utils.converter;

import java.text.NumberFormat;
import java.util.Locale;

/**
 * {@link ObjectConverter} implementation for a percentage
 */
public class PercentConverter extends DoubleConverter {

    public static final ConverterContext CONTEXT = new ConverterContext("Percent"); //NON-NLS

    public PercentConverter() {
        this(NumberFormat.getPercentInstance());
    }

    public PercentConverter(Locale locale) {
        this(NumberFormat.getPercentInstance(locale));
    }

    public PercentConverter(NumberFormat format) {
        super(format);
    }

    /**
     * Converts the String to a Double. It will use the NumberFormat defined as {@link #PROPERTY_NUMBER_FORMAT} if any.
     * If not there, it will use {@link #getNumberFormat()} to get the NumberFormat to do the conversion.
     * <p>
     * Different from a DoubleConverter, if the String doesn't have a percentage sign at the end, we will divide the
     * number from DoubleConverter by 100 and return the value. That's because "50%" actually is 0.5. If user forgot to
     * include a % sign, for example, pass in "50", we should still treat it as percentage and return 0.5 as they are
     * using a PercentConverter.
     * <p>
     * Please note, the conversion may involve rounding or truncation.
     *
     * @param string  the string to be converted.
     * @param context the context
     * @return the Number converted from the String.
     */
    @Override
    public Double fromString(String string, ConverterContext context) {
        Number number = numberFromString(string, context);
        if (number == null) {
            number = Double.parseDouble(string);
        }
        if (string != null && !string.trim().endsWith("%") && number != null) {
            number = number.doubleValue() / 100;
        }
        return number != null ? number.doubleValue() : null;
    }

}