/*
 * ============LICENSE_START=======================================================
 * PNF-REGISTRATION-HANDLER
 * ================================================================================
 * Copyright (C) 2018 NOKIA Intellectual Property. 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.
 * ============LICENSE_END=========================================================
 */

package org.onap.dcaegen2.services.prh.configuration;

import com.google.gson.JsonObject;
import org.onap.dcaegen2.services.sdk.rest.services.aai.client.config.AaiClientConfiguration;
import org.onap.dcaegen2.services.sdk.rest.services.cbs.client.api.CbsClientFactory;
import org.onap.dcaegen2.services.sdk.rest.services.cbs.client.api.CbsRequests;
import org.onap.dcaegen2.services.sdk.rest.services.cbs.client.model.CbsClientConfiguration;
import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.api.DmaapClientFactory;
import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.api.MessageRouterPublisher;
import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.api.MessageRouterSubscriber;
import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.model.MessageRouterPublishRequest;
import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.model.MessageRouterSubscribeRequest;
import org.onap.dcaegen2.services.sdk.rest.services.model.logging.RequestDiagnosticContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.annotation.Configuration;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
import reactor.core.scheduler.Schedulers;

import java.util.Optional;

@Configuration
public class CbsConfiguration implements Config {
    private static final Logger LOGGER = LoggerFactory.getLogger(CbsConfiguration.class);
    private static final String CBS_CONFIG_MISSING = "CBS config missing";
    private AaiClientConfiguration aaiClientCBSConfiguration;
    private MessageRouterPublisher messageRouterPublisher;
    private MessageRouterSubscriber messageRouterSubscriber;
    private MessageRouterPublishRequest messageRouterCBSPublishRequest;
    private MessageRouterSubscribeRequest messageRouterCBSSubscribeRequest;
    private MessageRouterPublishRequest messageRouterCBSUpdatePublishRequest;

    private final ConsulConfigFileReader consulConfigFileReader;

    public CbsConfiguration(ConsulConfigFileReader consulConfigFileReader) {
        this.consulConfigFileReader = consulConfigFileReader;
    }

    public void runTask() {
        Flux.defer(this::resolveCbsClientConfiguration)
            .subscribeOn(Schedulers.parallel())
            .subscribe(this::parsingConfigSuccess, this::parsingConfigError);
    }

    private Mono<CbsClientConfiguration> resolveCbsClientConfiguration() {
        try {
            return Mono.just(CbsClientConfiguration.fromEnvironment());
        } catch(Exception e){
            parsingConfigError(e);
            return consulConfigFileReader.evaluate();
        }
    }

    private void parsingConfigSuccess(CbsClientConfiguration cbsClientConfiguration) {
        LOGGER.debug("Fetching PRH configuration from Consul");
        CbsClientFactory.createCbsClient(cbsClientConfiguration)
            .flatMap(cbsClient -> cbsClient.get(CbsRequests.getAll(RequestDiagnosticContext.create())))
            .subscribe(this::parseCBSConfig, this::cbsConfigError);
    }

    private void parseCBSConfig(JsonObject jsonObject) {
        LOGGER.info("Received application configuration: {}", jsonObject);
        CbsContentParser consulConfigurationParser = new CbsContentParser(jsonObject);

        aaiClientCBSConfiguration = consulConfigurationParser.getAaiClientConfig();

        messageRouterPublisher = DmaapClientFactory.createMessageRouterPublisher(
                consulConfigurationParser.getMessageRouterPublisherConfig());
        messageRouterCBSPublishRequest = consulConfigurationParser.getMessageRouterPublishRequest();
        messageRouterCBSUpdatePublishRequest = consulConfigurationParser.getMessageRouterUpdatePublishRequest();

        messageRouterSubscriber = DmaapClientFactory.createMessageRouterSubscriber(
                consulConfigurationParser.getMessageRouterSubscriberConfig());
        messageRouterCBSSubscribeRequest = consulConfigurationParser.getMessageRouterSubscribeRequest();
    }

    private void parsingConfigError(Throwable throwable) {
        LOGGER.warn("Failed to process system environments", throwable);
    }

    private void cbsConfigError(Throwable throwable) {
        LOGGER.warn("Failed to gather configuration from ConfigBindingService/Consul", throwable);
    }


    @Override
    public MessageRouterPublisher getMessageRouterPublisher() {
        return Optional.ofNullable(messageRouterPublisher).orElseThrow(() -> new RuntimeException(CBS_CONFIG_MISSING));
    }

    @Override
    public MessageRouterSubscriber getMessageRouterSubscriber() {
        return Optional.ofNullable(messageRouterSubscriber).orElseThrow(() -> new RuntimeException(CBS_CONFIG_MISSING));
    }

    @Override
    public MessageRouterPublishRequest getMessageRouterPublishRequest() {
        return Optional.ofNullable(messageRouterCBSPublishRequest).orElseThrow(() -> new RuntimeException(CBS_CONFIG_MISSING));
    }

    @Override
    public MessageRouterPublishRequest getMessageRouterUpdatePublishRequest() {
        return Optional.ofNullable(messageRouterCBSUpdatePublishRequest).orElseThrow(() -> new RuntimeException(CBS_CONFIG_MISSING));
    }

    @Override
    public AaiClientConfiguration getAaiClientConfiguration() {
        return Optional.ofNullable(aaiClientCBSConfiguration).orElseThrow(() -> new RuntimeException(CBS_CONFIG_MISSING));
    }

    @Override
    public MessageRouterSubscribeRequest getMessageRouterSubscribeRequest() {
        return Optional.ofNullable(messageRouterCBSSubscribeRequest).orElseThrow(() -> new RuntimeException(CBS_CONFIG_MISSING));
    }
}