/*
 *  Copyright 2009-2013 Stephen Colebourne
 *
 *  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.joda.money;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Provider for available currencies using a file.
 * <p>
 * This reads currencies from two files.
 * Firstly it reads the mandatory resource named {@code /org/joda/money/MoneyData.csv}.
 * Then it reads the optional resource named {@code /org/joda/money/MoneyDataExtension.csv}.
 * Both will be read as the first found on the classpath.
 */
class DefaultCurrencyUnitDataProvider extends CurrencyUnitDataProvider {

    /** Regex format for the csv line. */
    private static final Pattern REGEX_LINE = Pattern.compile("([A-Z]{3}),(-1|[0-9]{1,3}),(-1|0|1|2|3),([A-Z]*)#?.*");

    /**
     * Registers all the currencies known by this provider.
     * 
     * @throws Exception if an error occurs
     */ 
    @Override
    protected void registerCurrencies() throws Exception {
        loadCurrenciesFromFile("/org/joda/money/MoneyData.csv", true);
        loadCurrenciesFromFile("/org/joda/money/MoneyDataExtension.csv", false);
    }
    
    /**
     * Loads Currencies from a file
     *  
     * @param fileName  the file to load, not null
     * @param isNecessary  whether or not the file is necessary
     * @throws Exception if a necessary file is not found
     */
    private void loadCurrenciesFromFile(String fileName, boolean isNecessary) throws Exception {
        InputStream in = getClass().getResourceAsStream(fileName);
        if (in == null && isNecessary) {
            throw new FileNotFoundException("Data file " + fileName + " not found");
        } else if (in == null && !isNecessary) {
            return; // no extension file found, no problem. just return
        }
        BufferedReader reader = new BufferedReader(new InputStreamReader(in, "UTF-8"));
        String line;
        while ((line = reader.readLine()) != null) {
            Matcher matcher = REGEX_LINE.matcher(line);
            if (matcher.matches()) {
                List<String> countryCodes = new ArrayList<String>();
                String codeStr = matcher.group(4);
                String currencyCode = matcher.group(1);
                if (codeStr.length() % 2 == 1) {
                    continue;  // invalid line
                }
                for (int i = 0; i < codeStr.length(); i += 2) {
                    countryCodes.add(codeStr.substring(i, i + 2));
                }
                int numericCode = Integer.parseInt(matcher.group(2));
                int digits = Integer.parseInt(matcher.group(3));
                registerCurrency(currencyCode, numericCode, digits, countryCodes);
            }
        }
    }

}

@@ -1479,15 +1479,13 @@
 (-1%7C
-0%7C1%7C2%7C3
+%5B0-9%5D
 ),(%5B

Allow up to 9 decimal places to be defined in CSV file.