/*******************************************************************************
 * Copyright 2016-2017 ZTE, Inc. and others.
 * 
 * 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.onap.msb.apiroute.wrapper.consulextend;

import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.onap.msb.apiroute.wrapper.consulextend.async.ConsulResponseCallback;
import org.onap.msb.apiroute.wrapper.consulextend.util.Http;
import org.onap.msb.apiroute.wrapper.util.ConfigUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.fasterxml.jackson.core.type.TypeReference;
import com.orbitz.consul.option.CatalogOptions;
import com.orbitz.consul.option.QueryOptions;

/**
 * HTTP Client for /v1/catalog/ endpoints.
 */
public class CatalogClient {

    private static final Logger LOGGER = LoggerFactory.getLogger(CatalogClient.class);

    private static final TypeReference<HttpEntity> TYPE_SERVICES_MAP = new TypeReference<HttpEntity>() {};


    private static final String CATALOG_URI_8500 = "/v1/catalog";
    private static final String CATAlOG_URI_10081 = "/api/catalog/v1";

    private static final String GET_SERVICES_URI = "/services";

    private static final Http httpClient = Http.getInstance();

    private HttpHost targetHost = null;
    private String catalogUri = CATAlOG_URI_10081;

    CatalogClient(final HttpHost targetHost) {
        this.targetHost = targetHost;
        if (targetHost.getPort() == 8500) {
            catalogUri = CATALOG_URI_8500;
        }
    }

    /**
     * Retrieves all services for a given datacenter with
     * {@link com.orbitz.consul.option.QueryOptions}.
     * 
     * GET /v1/catalog/services?dc={datacenter}
     * 
     * @param catalogOptions Catalog specific options to use.
     * @param queryOptions The Query Options to use.
     * @return A {@link com.orbitz.consul.model.ConsulResponse} containing a map of service name to
     *         list of tags.
     */
    public void getServices(CatalogOptions catalogOptions, QueryOptions queryOptions,
                    ConsulResponseCallback<HttpEntity> callback) {

        // prepare access path
        // path:10081 vs 8500
        String path = targetHost.toString() + catalogUri + GET_SERVICES_URI;

        // params:wait,index,dc......
        String params = Http.optionsFrom(catalogOptions, queryOptions);

        // node meta: ns,external,internal.....
        String node_meta = ConfigUtil.getInstance().getNodeMetaQueryParam();

        // add params
        path = (params != null && !params.isEmpty()) ? path += "?" + params : path;

        // add node_meta
        if (node_meta != null && !node_meta.isEmpty()) {
            path = path.contains("?") ? path + "&" + node_meta : path + "?" + node_meta;
        }

        // async watch services
        if (LOGGER.isDebugEnabled()) {
            LOGGER.debug("get all services:" + path);
        }
        httpClient.asyncGetDelayHandle(path, TYPE_SERVICES_MAP, callback);
    }
}