/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.karaf.config.core.impl;

import org.apache.felix.utils.properties.InterpolationHelper;
import org.osgi.framework.Constants;
import org.osgi.framework.ServiceReference;
import org.osgi.service.cm.ConfigurationPlugin;

import java.util.*;

public class KarafConfigurationPlugin implements ConfigurationPlugin {

    public static final String PLUGIN_ID = "org.apache.karaf.config.plugin";
    public static final int PLUGIN_RANKING = 500;

    @Override
    public void modifyConfiguration(ServiceReference<?> reference, Dictionary<String, Object> properties) {
        final Object pid = properties.get(Constants.SERVICE_PID);
        for (Enumeration<String> keys = properties.keys(); keys.hasMoreElements(); ) {
            String key = keys.nextElement();

            // looking for env variable and system property matching key (pid.key).toUpperCase().replace('.', '_').replace('-', '_').replace('~', '_')
            String env = (pid + "." + key).toUpperCase().replaceAll("\\.", "_").replace("-", "_").replace("~", "_");
            String sys = pid + "." + key;

            if (System.getenv(env) != null) {

                String value = System.getenv(env);

                if (value.startsWith("[") && value.endsWith("]")) {
                    String[] values = value.substring(1, value.length() - 1).split(",");
                    values = Arrays.stream(values).<String>map(e -> InterpolationHelper.substVars(e, null,null, convertDictionaryToMap(properties))).toArray(String[]::new);
                    properties.put(key, values);
                } else {
                    value = InterpolationHelper.substVars(value, null,null, convertDictionaryToMap(properties));
                    try {
                        int intValue = Integer.parseInt(value);
                        properties.put(key, intValue);
                    } catch (NumberFormatException e) {
                        properties.put(key, value);
                    }
                }
                
            } else if (System.getProperty(sys) != null) {

                String value = System.getProperty(sys);

                if (value.startsWith("[") && value.endsWith("]")) {
                    String[] values= value.substring(1, value.length() - 1).split(",");
                    values = Arrays.stream(values).<String>map(e -> InterpolationHelper.substVars(e, null,null, convertDictionaryToMap(properties))).toArray(String[]::new);
                    properties.put(key, values);
                } else {
                    value = InterpolationHelper.substVars(value, null,null, convertDictionaryToMap(properties));
                    try {
                        int intValue = Integer.parseInt(value);
                        properties.put(key, intValue);
                    } catch (NumberFormatException e) {
                        properties.put(key, value);
                    }
                }

            }
        }
    }

    private static Map<String, String> convertDictionaryToMap(Dictionary<String, Object> dictionary) {
        Map<String, String> converted = new HashMap<>();
        Enumeration<String> keys = dictionary.keys();
        while (keys.hasMoreElements()) {
            String key = keys.nextElement();
            converted.put(key, dictionary.get(key).toString());
        }
        return converted;
    }

}
