/*
 * 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.dubbo.registry.integration;

import org.apache.dubbo.common.URL;
import org.apache.dubbo.common.config.configcenter.ConfigChangeType;
import org.apache.dubbo.common.config.configcenter.ConfigChangedEvent;
import org.apache.dubbo.common.config.configcenter.ConfigurationListener;
import org.apache.dubbo.common.config.configcenter.DynamicConfiguration;
import org.apache.dubbo.common.logger.ErrorTypeAwareLogger;
import org.apache.dubbo.common.logger.LoggerFactory;
import org.apache.dubbo.common.utils.StringUtils;
import org.apache.dubbo.rpc.cluster.Configurator;
import org.apache.dubbo.rpc.cluster.configurator.parser.ConfigParser;
import org.apache.dubbo.rpc.cluster.governance.GovernanceRuleRepository;
import org.apache.dubbo.rpc.model.ModuleModel;

import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;

import static org.apache.dubbo.common.constants.LoggerCodeConstants.REGISTRY_FAILED_PARSE_DYNAMIC_CONFIG;
import static org.apache.dubbo.rpc.Constants.ACCESS_LOG_KEY;
import static org.apache.dubbo.rpc.cluster.Constants.ROUTER_KEY;
import static org.apache.dubbo.rpc.cluster.Constants.RULE_KEY;
import static org.apache.dubbo.rpc.cluster.Constants.RUNTIME_KEY;
import static org.apache.dubbo.rpc.cluster.Constants.TYPE_KEY;

/**
 * AbstractConfiguratorListener
 */
public abstract class AbstractConfiguratorListener implements ConfigurationListener {
    private static final ErrorTypeAwareLogger logger = LoggerFactory.getErrorTypeAwareLogger(AbstractConfiguratorListener.class);

    protected List<Configurator> configurators = Collections.emptyList();
    protected GovernanceRuleRepository ruleRepository;

    protected Set<String> securityKey = new HashSet<>();
    protected ModuleModel moduleModel;

    public AbstractConfiguratorListener(ModuleModel moduleModel) {
        this.moduleModel = moduleModel;

        ruleRepository = moduleModel.getExtensionLoader(GovernanceRuleRepository.class).getDefaultExtension();

        initSecurityKey();
    }

    private void initSecurityKey() {
        // accessLogKey and FileRouterFactory key
        securityKey.add(ACCESS_LOG_KEY);
        securityKey.add(ROUTER_KEY);
        securityKey.add(RULE_KEY);
        securityKey.add(RUNTIME_KEY);
        securityKey.add(TYPE_KEY);
    }

    protected final void initWith(String key) {
        ruleRepository.addListener(key, this);
        String rawConfig = ruleRepository.getRule(key, DynamicConfiguration.DEFAULT_GROUP);
        if (!StringUtils.isEmpty(rawConfig)) {
            genConfiguratorsFromRawRule(rawConfig);
        }
    }

    protected final void stopListen(String key) {
        ruleRepository.removeListener(key, this);
    }

    @Override
    public void process(ConfigChangedEvent event) {
        if (logger.isInfoEnabled()) {
            logger.info("Notification of overriding rule, change type is: " + event.getChangeType() +
                    ", raw config content is:\n " + event.getContent());
        }

        if (event.getChangeType().equals(ConfigChangeType.DELETED)) {
            configurators.clear();
        } else {
            // ADDED or MODIFIED
            if (!genConfiguratorsFromRawRule(event.getContent())) {
                return;
            }
        }

        notifyOverrides();
    }

    private boolean genConfiguratorsFromRawRule(String rawConfig) {
        List<URL> urls;
        try {
            // parseConfigurators will recognize app/service config automatically.
            urls = ConfigParser.parseConfigurators(rawConfig);
        } catch (Exception e) {
            // 1-14 - Failed to parse raw dynamic config.

            logger.warn(REGISTRY_FAILED_PARSE_DYNAMIC_CONFIG, "", "",
                "Failed to parse raw dynamic config and it will not take effect, the raw config is: "
                    + rawConfig + ", cause: " + e.getMessage());

            return false;
        }
        List<URL> safeUrls = urls.stream()
            .map(url -> url.removeParameters(securityKey))
            .map(url -> url.setScopeModel(moduleModel))
            .collect(Collectors.toList());
        configurators = Configurator.toConfigurators(safeUrls).orElse(configurators);
        return true;
    }

    protected abstract void notifyOverrides();

    public List<Configurator> getConfigurators() {
        return configurators;
    }

    public void setConfigurators(List<Configurator> configurators) {
        this.configurators = configurators;
    }
}
