/**
 * Copyright 2017 ZTE Corporation.
 *
 * 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.aai.esr.wrapper;

import java.util.ArrayList;
import java.util.List;
import javax.ws.rs.core.Response;
import org.onap.aai.esr.entity.rest.EmsRegisterInfo;
import org.onap.aai.esr.exception.ExceptionUtil;
import org.onap.aai.esr.exception.ExtsysException;
import org.onap.aai.esr.externalservice.aai.ExternalSystemProxy;
import org.onap.aai.esr.util.EmsManagerUtil;
import org.onap.aai.esr.entity.aai.EsrEmsDetail;
import org.onap.aai.esr.entity.aai.EsrEmsList;
import org.onap.aai.esr.entity.aai.EsrSystemInfo;
import org.onap.aai.esr.entity.rest.CommonRegisterResponse;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.gson.Gson;

public class EmsManagerWrapper {
    private static EmsManagerWrapper emsManagerWrapper;
    private static final Logger LOG = LoggerFactory.getLogger(EmsManagerWrapper.class);
    private static EmsManagerUtil emsManagerUtil = new EmsManagerUtil();
    private static ExternalSystemProxy externalSystemProxy = new ExternalSystemProxy();
    /**
     * get VnfmManagerWrapper instance.
     * 
     * @return ems manager wrapper instance
     */
    public static EmsManagerWrapper getInstance() {
        if (emsManagerWrapper == null) {
            emsManagerWrapper = new EmsManagerWrapper(externalSystemProxy);
        }
        return emsManagerWrapper;
    }
    
    public EmsManagerWrapper(ExternalSystemProxy externalSystemProxy){
        EmsManagerWrapper.externalSystemProxy = externalSystemProxy;
    }

    public Response registerEms(EmsRegisterInfo emsRegisterInfo) {
        CommonRegisterResponse result = new CommonRegisterResponse();
        EsrEmsDetail esrEmsDetail = emsManagerUtil.emsRegisterInfo2EsrEms(emsRegisterInfo);
        String emsId = esrEmsDetail.getEmsId();
        try {
            externalSystemProxy.registerEms(emsId, esrEmsDetail);
            result.setId(emsId);
            return Response.ok(result).build();
        } catch (ExtsysException e) {
            LOG.error("Register EMS failed !", e);
            throw ExceptionUtil.buildExceptionResponse(e.getMessage());
        }
    }

    public Response updateEms(EmsRegisterInfo emsRegisterInfo, String emsId) {
        CommonRegisterResponse result = new CommonRegisterResponse();
        EsrEmsDetail esrEmsDetail = getNewEsrEmsDetail(emsRegisterInfo, emsId);
        try {
            externalSystemProxy.registerEms(emsId, esrEmsDetail);
            result.setId(emsId);
            return Response.ok(result).build();
        } catch (ExtsysException e) {
            LOG.error("Update VNFM failed !", e);
            throw ExceptionUtil.buildExceptionResponse(e.getMessage());
        }
    }

    public Response queryEmsList() {
        List<EmsRegisterInfo> emsList = new ArrayList<>();
        EsrEmsList esrEms = new EsrEmsList();
        try {
            String esrEmsStr = externalSystemProxy.queryEmsList();
            esrEms = new Gson().fromJson(esrEmsStr, EsrEmsList.class);
            LOG.info("Response from AAI by query EMS list: " + esrEms);
            emsList = getEmsDetailList(esrEms);
            return Response.ok(emsList).build();
        } catch (ExtsysException e) {
            LOG.error("Query EMS list failed !", e);
            return Response.ok(emsList).build();
        }
    }

    public Response queryEmsById(String emsId) {
        EmsRegisterInfo ems = queryEmsDetail(emsId);
        if (ems != null) {
            return Response.ok(ems).build();
        } else {
            return Response.ok(ems).build();
        }
    }

    public Response delEms(String emsId) {
        EsrEmsDetail esrEmsDetail = queryEsrEmsDetail(emsId);
        String resourceVersion = esrEmsDetail.getResourceVersion();
        try {
            externalSystemProxy.deleteEms(emsId, resourceVersion);
            return Response.noContent().build();
        } catch (ExtsysException e) {
            LOG.error("Delete EMS from A&AI failed! EMS ID: " + emsId + "resouce-version:" + resourceVersion, e);
            throw ExceptionUtil.buildExceptionResponse(e.getMessage());
        }
    }

    private EmsRegisterInfo queryEmsDetail(String emsId) {
        EmsRegisterInfo emsRegisterInfo = new EmsRegisterInfo();
        EsrEmsDetail esrEmsDetail = new EsrEmsDetail();
        try {
            String esrEmsStr = externalSystemProxy.queryEmsDetail(emsId);
            LOG.info("Response from AAI by query EMS: " + esrEmsStr);
            esrEmsDetail = new Gson().fromJson(esrEmsStr, EsrEmsDetail.class);
            emsRegisterInfo = emsManagerUtil.EsrEms2EmsRegisterInfo(esrEmsDetail);
        } catch (ExtsysException e) {
            LOG.error("Query EMS detail failed! EMS ID: " + emsId, e);
        }
        return emsRegisterInfo;
    }

    private List<EmsRegisterInfo> getEmsDetailList(EsrEmsList esrEms) {
        List<EmsRegisterInfo> emsInfoList = new ArrayList<>();
        for (int i = 0; i < esrEms.getEsrEms().size(); i++) {
            String emsId = esrEms.getEsrEms().get(i).getEmsId();
            EmsRegisterInfo emsInfo = queryEmsDetail(emsId);
            if (emsInfo != null) {
                emsInfoList.add(emsInfo);
            }
        }
        return emsInfoList;
    }

    private EsrEmsDetail queryEsrEmsDetail(String emsId) {
        EsrEmsDetail esrEmsDetail = new EsrEmsDetail();
        try {
            String esrEmsStr = externalSystemProxy.queryEmsDetail(emsId);
            LOG.info("Response from AAI by query EMS: " + esrEmsStr);
            esrEmsDetail = new Gson().fromJson(esrEmsStr, EsrEmsDetail.class);
        } catch (ExtsysException e) {
            LOG.error("Query EMS detail failed! EMS ID: " + emsId, e);
        }
        return esrEmsDetail;
    }

    private EsrEmsDetail getNewEsrEmsDetail(EmsRegisterInfo emsRegisterInfo, String emsId) {
        EsrEmsDetail oriEsrEmsDetail = queryEsrEmsDetail(emsId);
        EsrEmsDetail esrEmsDetail = emsManagerUtil.emsRegisterInfo2EsrEms(emsRegisterInfo);
        String emsResourceVersion = oriEsrEmsDetail.getResourceVersion();
        esrEmsDetail.setResourceVersion(emsResourceVersion);
        esrEmsDetail.setEmsId(emsId);
        List<EsrSystemInfo> newEsrSysInfoList = esrEmsDetail.getEsrSystemInfoList().getEsrSystemInfo();
        List<EsrSystemInfo> oriEsrSysInfoList = oriEsrEmsDetail.getEsrSystemInfoList().getEsrSystemInfo();
        for (int i = 0; i < oriEsrSysInfoList.size(); i++) {
            EsrSystemInfo originalEsrSystemInfo = oriEsrSysInfoList.get(i);
            for (int j = 0; j < newEsrSysInfoList.size(); j++) {
                EsrSystemInfo newEsrSystemInfo = newEsrSysInfoList.get(j);
                if (originalEsrSystemInfo.getSystemType().equals(newEsrSystemInfo.getSystemType())) {
                    esrEmsDetail.getEsrSystemInfoList().getEsrSystemInfo().get(j)
                            .setResouceVersion(originalEsrSystemInfo.getResouceVersion());
                    esrEmsDetail.getEsrSystemInfoList().getEsrSystemInfo().get(j)
                            .setEsrSystemInfoId(originalEsrSystemInfo.getEsrSystemInfoId());
                    break;
                }
            }
        }
        return esrEmsDetail;
    }
}