/*-
 * ============LICENSE_START=======================================================
 * ONAP : APPC
 * ================================================================================
 * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * Copyright (C) 2017 Amdocs
 * =============================================================================
 * 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.
 * 
 * ECOMP is a trademark and service mark of AT&T Intellectual Property.
 * ============LICENSE_END=========================================================
 */

package org.openecomp.appc.adapter.iaas.provider.operation.impl;

import com.att.cdp.exceptions.ContextConnectionException;
import com.att.cdp.exceptions.ResourceNotFoundException;
import com.att.cdp.exceptions.ZoneException;
import com.att.cdp.zones.ComputeService;
import com.att.cdp.zones.Context;
import com.att.cdp.zones.ImageService;
import com.att.cdp.zones.Provider;
import com.att.cdp.zones.model.Image;
import com.att.cdp.zones.model.ModelObject;
import com.att.cdp.zones.model.Server;
import com.att.cdp.zones.model.ServerBootSource;
import com.att.eelf.configuration.EELFLogger;
import com.att.eelf.configuration.EELFManager;
import com.att.eelf.i18n.EELFResourceManager;
import org.glassfish.grizzly.http.util.HttpStatus;
import org.openecomp.appc.Constants;
import org.openecomp.appc.adapter.iaas.ProviderAdapter;
import org.openecomp.appc.adapter.iaas.impl.IdentityURL;
import org.openecomp.appc.adapter.iaas.impl.RequestContext;
import org.openecomp.appc.adapter.iaas.impl.RequestFailedException;
import org.openecomp.appc.adapter.iaas.impl.VMURL;
import org.openecomp.appc.adapter.iaas.provider.operation.common.enums.Operation;
import org.openecomp.appc.adapter.iaas.provider.operation.common.enums.Outcome;
import org.openecomp.appc.adapter.iaas.provider.operation.impl.base.ProviderServerOperation;
import org.openecomp.appc.configuration.Configuration;
import org.openecomp.appc.configuration.ConfigurationFactory;
import org.openecomp.appc.exceptions.APPCException;
import org.openecomp.appc.i18n.Msg;
import org.onap.ccsdk.sli.core.sli.SvcLogicContext;
import org.slf4j.MDC;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Map;
import java.util.TimeZone;
import static org.openecomp.appc.adapter.iaas.provider.operation.common.enums.Operation.STOP_SERVICE;
import static org.openecomp.appc.adapter.utils.Constants.ADAPTER_NAME;

public class RebuildServer extends ProviderServerOperation {

    private static final EELFLogger logger = EELFManager.getInstance().getLogger(RebuildServer.class);
    private static EELFLogger metricsLogger = EELFManager.getInstance().getMetricsLogger();
    private static final Configuration configuration = ConfigurationFactory.getConfiguration();

    /**
     * Rebuild the indicated server with the indicated image. This method assumes the server has been determined to be
     * in the correct state to do the rebuild.
     *
     * @param rc The request context that manages the state and recovery of the request for the life of its processing.
     * @param server the server to be rebuilt
     * @param image The image to be used (or snapshot)
     * @throws RequestFailedException if the server does not change state in the allotted time
     */
    @SuppressWarnings("nls")
    private void rebuildServer(RequestContext rc, Server server, String image) throws RequestFailedException {
        logger.debug(Msg.REBUILD_SERVER, server.getId());

        String msg;
        Context context = server.getContext();
        Provider provider = context.getProvider();
        ComputeService service = context.getComputeService();

        /*
         * Set Time for Metrics Logger
         */
        setTimeForMetricsLogger();

        try {
            while (rc.attempt()) {
                try {
                    server.rebuild(image);
                    break;
                } catch (ContextConnectionException e) {
                    msg = EELFResourceManager.format(Msg.CONNECTION_FAILED_RETRY, provider.getName(), service.getURL(),
                            context.getTenant().getName(), context.getTenant().getId(), e.getMessage(),
                            Long.toString(rc.getRetryDelay()), Integer.toString(rc.getAttempts()),
                            Integer.toString(rc.getRetryLimit()));
                    logger.error(msg, e);
                    metricsLogger.error(msg, e);
                    rc.delay();
                }
            }

            /*
             * We need to provide some time for OpenStack to start processing the request.
             */
            try {
                Thread.sleep(10L * 1000L);
            } catch (InterruptedException e) {
                logger.trace("Sleep threw interrupted exception, should never occur");
                metricsLogger.trace("Sleep threw interrupted exception, should never occur");
            }
        } catch (ZoneException e) {
            msg = EELFResourceManager.format(Msg.REBUILD_SERVER_FAILED, server.getName(), server.getId(),
                    e.getMessage());
            logger.error(msg);
            metricsLogger.error(msg);
            throw new RequestFailedException("Rebuild Server", msg, HttpStatus.BAD_GATEWAY_502, server);
        }

        rc.reset();
        /*
         * Once we have started the process, now we wait for the final state of stopped. This should be the final state
         * (since we started the rebuild with the server stopped).
         */
        waitForStateChange(rc, server, Server.Status.READY);

        if (rc.isFailed()) {
            msg = EELFResourceManager.format(Msg.CONNECTION_FAILED, provider.getName(), service.getURL());
            logger.error(msg);
            metricsLogger.error(msg);
            throw new RequestFailedException("Rebuild Server", msg, HttpStatus.BAD_GATEWAY_502, server);
        }
        rc.reset();
    }

    /**
     * This method is called to rebuild the provided server.
     * <p>
     * If the server was booted from a volume, then the request is failed immediately and no action is taken. Rebuilding
     * a VM from a bootable volume, where the bootable volume itself is not rebuilt, serves no purpose.
     * </p>
     *
     * @param rc The request context that manages the state and recovery of the request for the life of its processing.
     * @param server The server to be rebuilt
     * @throws ZoneException When error occurs
     * @throws RequestFailedException When server status is error
     */
    @SuppressWarnings("nls")
    private void rebuildServer(RequestContext rc, Server server, SvcLogicContext ctx)
            throws ZoneException, RequestFailedException {
        ServerBootSource builtFrom = server.getBootSource();

        /*
         * Set Time for Metrics Logger
         */
        setTimeForMetricsLogger();

        String msg;
        // Throw exception for non image/snap boot source
        if (ServerBootSource.VOLUME.equals(builtFrom)) {
            msg = String.format("Rebuilding is currently not supported for servers built from bootable volumes [%s]",
                    server.getId());
            generateEvent(rc, false, msg);
            logger.error(msg);
            metricsLogger.error(msg);
            throw new RequestFailedException("Rebuild Server", msg, HttpStatus.FORBIDDEN_403, server);
        }

        /*
         * Pending is a bit of a special case. If we find the server is in a pending state, then the provider is in the
         * process of changing state of the server. So, lets try to wait a little bit and see if the state settles down
         * to one we can deal with. If not, then we have to fail the request.
         */
        Context context = server.getContext();
        Provider provider = context.getProvider();
        ComputeService service = context.getComputeService();
        if (server.getStatus().equals(Server.Status.PENDING)) {
            rc.reset();
            waitForStateChange(rc, server, Server.Status.READY, Server.Status.RUNNING, Server.Status.ERROR,
                    Server.Status.SUSPENDED, Server.Status.PAUSED);
        }

        // Is the skip Hypervisor check attribute populated?
        String skipHypervisorCheck = configuration.getProperty("org.openecomp.appc.iaas.skiphypervisorchek");
        if (skipHypervisorCheck == null && ctx != null) {
            skipHypervisorCheck = ctx.getAttribute(ProviderAdapter.SKIP_HYPERVISOR_CHECK);
        }

        // Always perform Hypervisor Status checks
        // unless the skip is set to true
        if (skipHypervisorCheck == null || (!skipHypervisorCheck.equalsIgnoreCase("true"))) {
            // Check of the Hypervisor for the VM Server is UP and reachable
            checkHypervisor(server);
        }

        /*
         * Get the image to use. This is determined by the presence or absence of snapshot images. If any snapshots
         * exist, then the latest snapshot is used, otherwise the image used to construct the VM is used.
         */
        List<Image> snapshots = server.getSnapshots();
        String imageToUse;
        if (snapshots != null && !snapshots.isEmpty()) {
            imageToUse = snapshots.get(0).getId();
        } else {
            imageToUse = server.getImage();
            ImageService imageService = server.getContext().getImageService();
            rc.reset();
            try {
                while (rc.attempt()) {
                    try {
                        /*
                         * We are just trying to make sure that the image exists. We arent interested in the details at
                         * this point.
                         */
                        imageService.getImage(imageToUse);
                        break;
                    } catch (ContextConnectionException e) {
                        msg = EELFResourceManager.format(Msg.CONNECTION_FAILED_RETRY, provider.getName(),
                                imageService.getURL(), context.getTenant().getName(), context.getTenant().getId(),
                                e.getMessage(), Long.toString(rc.getRetryDelay()), Integer.toString(rc.getAttempts()),
                                Integer.toString(rc.getRetryLimit()));
                        logger.error(msg, e);
                        metricsLogger.error(msg);
                        rc.delay();
                    }
                }
            } catch (ZoneException e) {
                msg = EELFResourceManager.format(Msg.IMAGE_NOT_FOUND, imageToUse, "rebuild");
                generateEvent(rc, false, msg);
                logger.error(msg);
                metricsLogger.error(msg);
                throw new RequestFailedException("Rebuild Server", msg, HttpStatus.METHOD_NOT_ALLOWED_405, server);
            }
        }
        if (rc.isFailed()) {
            msg = EELFResourceManager.format(Msg.CONNECTION_FAILED, provider.getName(), service.getURL());
            logger.error(msg);
            metricsLogger.error(msg);
            throw new RequestFailedException("Rebuild Server", msg, HttpStatus.BAD_GATEWAY_502, server);
        }
        rc.reset();

        /*
         * We determine what to do based on the current state of the server
         */
        switch (server.getStatus()) {
            case DELETED:
                // Nothing to do, the server is gone
                msg = EELFResourceManager.format(Msg.SERVER_DELETED, server.getName(), server.getId(),
                        server.getTenantId(), "rebuilt");
                generateEvent(rc, false, msg);
                logger.error(msg);
                metricsLogger.error(msg);
                throw new RequestFailedException("Rebuild Server", msg, HttpStatus.METHOD_NOT_ALLOWED_405, server);

            case RUNNING:
                // Attempt to stop the server, then rebuild it
                stopServer(rc, server);
                rc.reset();
                rebuildServer(rc, server, imageToUse);
                rc.reset();
                startServer(rc, server);
                generateEvent(rc, true, Outcome.SUCCESS.toString());
                metricsLogger.info("Server status: RUNNING");
                break;

            case ERROR:
                msg = EELFResourceManager.format(Msg.SERVER_ERROR_STATE, server.getName(), server.getId(),
                        server.getTenantId(), "rebuild");
                generateEvent(rc, false, msg);
                logger.error(msg);
                metricsLogger.error(msg);
                throw new RequestFailedException("Rebuild Server", msg, HttpStatus.METHOD_NOT_ALLOWED_405, server);

            case READY:
                // Attempt to rebuild the server
                rebuildServer(rc, server, imageToUse);
                rc.reset();
                startServer(rc, server);
                generateEvent(rc, true, Outcome.SUCCESS.toString());
                metricsLogger.info("Server status: READY");
                break;

            case PAUSED:
                // if paused, un-pause it, stop it, and rebuild it
                unpauseServer(rc, server);
                rc.reset();
                stopServer(rc, server);
                rc.reset();
                rebuildServer(rc, server, imageToUse);
                rc.reset();
                startServer(rc, server);
                generateEvent(rc, true, Outcome.SUCCESS.toString());
                metricsLogger.info("Server status: PAUSED");
                break;

            case SUSPENDED:
                // Attempt to resume the suspended server, stop it, and rebuild it
                resumeServer(rc, server);
                rc.reset();
                stopServer(rc, server);
                rc.reset();
                rebuildServer(rc, server, imageToUse);
                rc.reset();
                startServer(rc, server);
                generateEvent(rc, true, Outcome.SUCCESS.toString());
                metricsLogger.info("Server status: SUSPENDED");
                break;

            default:
                // Hmmm, unknown status, should never occur
                msg = EELFResourceManager.format(Msg.UNKNOWN_SERVER_STATE, server.getName(), server.getId(),
                        server.getTenantId(), server.getStatus().name());
                generateEvent(rc, false, msg);
                logger.error(msg);
                metricsLogger.error(msg);
                throw new RequestFailedException("Rebuild Server", msg, HttpStatus.METHOD_NOT_ALLOWED_405, server);
        }
    }

    /**
     * @see org.openecomp.appc.adapter.iaas.ProviderAdapter#rebuildServer(java.util.Map,
     *      org.openecomp.sdnc.sli.SvcLogicContext)
     */
    @SuppressWarnings("nls")
    public Server rebuildServer(Map<String, String> params, SvcLogicContext ctx) throws APPCException {
        Server server = null;
        RequestContext rc = new RequestContext(ctx);
        rc.isAlive();

        setTimeForMetricsLogger();

        String msg;
        try {
            validateParametersExist(params, ProviderAdapter.PROPERTY_INSTANCE_URL,
                    ProviderAdapter.PROPERTY_PROVIDER_NAME);

            String appName = configuration.getProperty(Constants.PROPERTY_APPLICATION_NAME);
            String vm_url = params.get(ProviderAdapter.PROPERTY_INSTANCE_URL);
            VMURL vm = VMURL.parseURL(vm_url);
            if (validateVM(rc, appName, vm_url, vm))
                return null;

            IdentityURL ident = IdentityURL.parseURL(params.get(ProviderAdapter.PROPERTY_IDENTITY_URL));
            String identStr = (ident == null) ? null : ident.toString();
            ctx.setAttribute("REBUILD_STATUS", "ERROR");

            Context context = null;
            try {
                context = getContext(rc, vm_url, identStr);
                if (context != null) {
                    rc.reset();
                    server = lookupServer(rc, context, vm.getServerId());
                    logger.debug(Msg.SERVER_FOUND, vm_url, context.getTenantName(), server.getStatus().toString());

                    // Manually checking image service until new PAL release
                    if (hasImageAccess(rc, context)) {
                        rebuildServer(rc, server, ctx);
                        doSuccess(rc);
                        ctx.setAttribute("REBUILD_STATUS", "SUCCESS");
                    } else {
                        msg = EELFResourceManager.format(Msg.REBUILD_SERVER_FAILED, server.getName(), server.getId(),
                                "Accessing Image Service Failed");
                        logger.error(msg);
                        metricsLogger.error(msg);
                        doFailure(rc, HttpStatus.FORBIDDEN_403, msg);
                    }
                    context.close();
                } else {
                    ctx.setAttribute("REBUILD_STATUS", "CONTEXT_NOT_FOUND");
                }
            } catch (RequestFailedException e) {
                doFailure(rc, e.getStatus(), e.getMessage());
                ctx.setAttribute("REBUILD_STATUS", "ERROR");
            } catch (ResourceNotFoundException e) {
                msg = EELFResourceManager.format(Msg.SERVER_NOT_FOUND, e, vm_url);
                ctx.setAttribute("REBUILD_STATUS", "ERROR");
                logger.error(msg);
                metricsLogger.error(msg);
                doFailure(rc, HttpStatus.NOT_FOUND_404, msg);
            } catch (Exception e1) {
                msg = EELFResourceManager.format(Msg.SERVER_OPERATION_EXCEPTION, e1, e1.getClass().getSimpleName(),
                        STOP_SERVICE.toString(), vm_url, context == null ? "Unknown" : context.getTenantName());
                ctx.setAttribute("REBUILD_STATUS", "ERROR");
                logger.error(msg, e1);
                metricsLogger.error(msg);
                doFailure(rc, HttpStatus.INTERNAL_SERVER_ERROR_500, msg);
            }
        } catch (RequestFailedException e) {
            doFailure(rc, e.getStatus(), e.getMessage());
            ctx.setAttribute("REBUILD_STATUS", "ERROR");
        }

        return server;
    }

    @Override
    protected ModelObject executeProviderOperation(Map<String, String> params, SvcLogicContext context)
            throws APPCException {
        setMDC(Operation.REBUILD_SERVICE.toString(), "App-C IaaS Adapter:Rebuild", ADAPTER_NAME);
        logOperation(Msg.REBUILDING_SERVER, params, context);

        setTimeForMetricsLogger();

        metricsLogger.info("Executing Provider Operation: Rebuild");

        return rebuildServer(params, context);
    }

    private void setTimeForMetricsLogger() {
        long startTime = System.currentTimeMillis();
        TimeZone tz = TimeZone.getTimeZone("UTC");
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ");
        df.setTimeZone(tz);
        long endTime = System.currentTimeMillis();
        long duration = endTime - startTime;
        String durationStr = String.valueOf(duration);
        String endTimeStrUTC = df.format(new Date());
        MDC.put("EndTimestamp", endTimeStrUTC);
        MDC.put("ElapsedTime", durationStr);
        MDC.put("TargetEntity", "cdp");
        MDC.put("TargetServiceName", "rebuild server");
        MDC.put("ClassName", "org.openecomp.appc.adapter.iaas.provider.operation.impl.RebuildServer");
    }
}