/*
 * Copyright (c) 2016, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
 *
 * WSO2 Inc. 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.wso2.carbon.device.mgt.iot.raspberrypi.service.impl;

import org.apache.commons.io.FileUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.wso2.carbon.analytics.dataservice.commons.SortByField;
import org.wso2.carbon.analytics.dataservice.commons.SortType;
import org.wso2.carbon.analytics.datasource.commons.exception.AnalyticsException;
import org.wso2.carbon.apimgt.application.extension.APIManagementProviderService;
import org.wso2.carbon.apimgt.application.extension.dto.ApiApplicationKey;
import org.wso2.carbon.apimgt.application.extension.exception.APIManagerException;
import org.wso2.carbon.context.PrivilegedCarbonContext;
import org.wso2.carbon.device.mgt.common.*;
import org.wso2.carbon.device.mgt.common.authorization.DeviceAccessAuthorizationException;
import org.wso2.carbon.device.mgt.common.group.mgt.DeviceGroupConstants;
import org.wso2.carbon.device.mgt.common.operation.mgt.Operation;
import org.wso2.carbon.device.mgt.common.operation.mgt.OperationManagementException;
import org.wso2.carbon.device.mgt.core.operation.mgt.CommandOperation;
import org.wso2.carbon.device.mgt.iot.raspberrypi.service.impl.constants.RaspberrypiConstants;
import org.wso2.carbon.device.mgt.iot.raspberrypi.service.impl.dto.SensorRecord;
import org.wso2.carbon.device.mgt.iot.raspberrypi.service.impl.util.APIUtil;
import org.wso2.carbon.device.mgt.iot.raspberrypi.service.impl.util.ZipArchive;
import org.wso2.carbon.device.mgt.iot.raspberrypi.service.impl.util.ZipUtil;
import org.wso2.carbon.identity.jwt.client.extension.JWTClient;
import org.wso2.carbon.identity.jwt.client.extension.dto.AccessTokenInfo;
import org.wso2.carbon.identity.jwt.client.extension.exception.JWTClientException;
import org.wso2.carbon.user.api.UserStoreException;

import javax.ws.rs.*;
import javax.ws.rs.core.Response;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.util.*;

public class RaspberryPiServiceImpl implements RaspberryPiService {

    private static Log log = LogFactory.getLog(RaspberryPiServiceImpl.class);
    private static final String KEY_TYPE = "PRODUCTION";
    private static ApiApplicationKey apiApplicationKey;

    @Path("device/{deviceId}/bulb")
    @POST
    public Response switchBulb(@PathParam("deviceId") String deviceId, @QueryParam("state") String state) {
        try {
            if (!APIUtil.getDeviceAccessAuthorizationService().isUserAuthorized(new DeviceIdentifier(deviceId,
                    RaspberrypiConstants.DEVICE_TYPE), DeviceGroupConstants.Permissions.DEFAULT_OPERATOR_PERMISSIONS)) {
                return Response.status(Response.Status.UNAUTHORIZED.getStatusCode()).build();
            }
            String switchToState = state.toUpperCase();
            if (!switchToState.equals(RaspberrypiConstants.STATE_ON) && !switchToState.equals(
                    RaspberrypiConstants.STATE_OFF)) {
                log.error("The requested state change shoud be either - 'ON' or 'OFF'");
                return Response.status(Response.Status.BAD_REQUEST.getStatusCode()).build();
            }
            String actualMessage = RaspberrypiConstants.BULB_CONTEXT + ":" + state;
            String publishTopic = APIUtil.getTenantDomainOftheUser() + "/"
                    + RaspberrypiConstants.DEVICE_TYPE + "/" + deviceId;

            Operation commandOp = new CommandOperation();
            commandOp.setCode("bulb");
            commandOp.setType(Operation.Type.COMMAND);
            commandOp.setEnabled(true);
            commandOp.setPayLoad(actualMessage);

            Properties props = new Properties();
            props.setProperty(RaspberrypiConstants.MQTT_ADAPTER_TOPIC_PROPERTY_NAME, publishTopic);
            commandOp.setProperties(props);

            List<DeviceIdentifier> deviceIdentifiers = new ArrayList<>();
            deviceIdentifiers.add(new DeviceIdentifier(deviceId, RaspberrypiConstants.DEVICE_TYPE));
            APIUtil.getDeviceManagementService().addOperation(RaspberrypiConstants.DEVICE_TYPE, commandOp,
                    deviceIdentifiers);
            return Response.ok().build();
        } catch (InvalidDeviceException e) {
            String msg = "Invalid Device Identifiers found.";
            log.error(msg, e);
            return Response.status(Response.Status.BAD_REQUEST).build();
        } catch (DeviceAccessAuthorizationException e) {
            log.error(e.getErrorMessage(), e);
            return Response.status(Response.Status.INTERNAL_SERVER_ERROR).build();
        } catch (OperationManagementException e) {
            String msg = "Error occurred while executing command operation upon switch the bulb";
            log.error(msg, e);
            return Response.status(Response.Status.INTERNAL_SERVER_ERROR).build();
        }
    }

    @Path("device/stats/{deviceId}")
    @GET
    @Consumes("application/json")
    @Produces("application/json")
    public Response getRaspberryPiTemperatureStats(@PathParam("deviceId") String deviceId,
                                                   @QueryParam("from") long from, @QueryParam("to") long to) {
        String fromDate = String.valueOf(from*1000);
        String toDate = String.valueOf(to*1000);
        String query = "meta_deviceId:" + deviceId + " AND meta_deviceType:" +
                RaspberrypiConstants.DEVICE_TYPE + " AND meta_time : [" + fromDate + " TO " + toDate + "]";
        String sensorTableName = RaspberrypiConstants.TEMPERATURE_EVENT_TABLE;
        try {
            if (!APIUtil.getDeviceAccessAuthorizationService().isUserAuthorized(new DeviceIdentifier(deviceId,
                    RaspberrypiConstants.DEVICE_TYPE), DeviceGroupConstants.Permissions.DEFAULT_STATS_MONITOR_PERMISSIONS)) {
                return Response.status(Response.Status.UNAUTHORIZED.getStatusCode()).build();
            }
            List<SortByField> sortByFields = new ArrayList<>();
            SortByField sortByField = new SortByField("meta_time", SortType.ASC);
            sortByFields.add(sortByField);
            List<SensorRecord> sensorRecords = APIUtil.getAllEventsForDevice(sensorTableName, query, sortByFields);
            return Response.status(Response.Status.OK.getStatusCode()).entity(sensorRecords).build();
        } catch (AnalyticsException e) {
            String errorMsg = "Error on retrieving stats on table " + sensorTableName + " with query " + query;
            log.error(errorMsg);
            return Response.status(Response.Status.INTERNAL_SERVER_ERROR.getStatusCode()).entity(errorMsg).build();
        } catch (DeviceAccessAuthorizationException e) {
            log.error(e.getErrorMessage(), e);
            return Response.status(Response.Status.INTERNAL_SERVER_ERROR).build();
        }
    }

    @Override
    @Path("device/download")
    @GET
    @Produces("application/zip")
    public Response downloadSketch(@QueryParam("deviceName") String deviceName, @QueryParam("sketchType") String sketchType) {
        try {
            String username = APIUtil.getAuthenticatedUser() + "@" + PrivilegedCarbonContext
                    .getThreadLocalCarbonContext().getTenantDomain();
            ZipArchive zipFile = createDownloadFile(username, deviceName, sketchType);
            Response.ResponseBuilder response = Response.ok(zipFile.getZipFileContent());
            response.status(Response.Status.OK);
            response.type("application/zip");
            response.header("Content-Disposition", "attachment; filename=\"" + zipFile.getFileName() + "\"");
            Response resp = response.build();
            return resp;
        } catch (IllegalArgumentException ex) {
            return Response.status(400).entity(ex.getMessage()).build();//bad request
        } catch (DeviceManagementException ex) {
            log.error(ex.getMessage(), ex);
            return Response.status(500).entity(ex.getMessage()).build();
        } catch (JWTClientException ex) {
            log.error(ex.getMessage(), ex);
            return Response.status(500).entity(ex.getMessage()).build();
        } catch (APIManagerException ex) {
            log.error(ex.getMessage(), ex);
            return Response.status(500).entity(ex.getMessage()).build();
        } catch (UserStoreException ex) {
            log.error(ex.getMessage(), ex);
            return Response.status(500).entity(ex.getMessage()).build();
        }
    }

    private boolean register(String deviceId, String name) {
        try {
            DeviceIdentifier deviceIdentifier = new DeviceIdentifier();
            deviceIdentifier.setId(deviceId);
            deviceIdentifier.setType(RaspberrypiConstants.DEVICE_TYPE);
            if (APIUtil.getDeviceManagementService().isEnrolled(deviceIdentifier)) {
                return false;
            }
            Device device = new Device();
            device.setDeviceIdentifier(deviceId);
            EnrolmentInfo enrolmentInfo = new EnrolmentInfo();
            enrolmentInfo.setDateOfEnrolment(new Date().getTime());
            enrolmentInfo.setDateOfLastUpdate(new Date().getTime());
            enrolmentInfo.setStatus(EnrolmentInfo.Status.ACTIVE);
            enrolmentInfo.setOwnership(EnrolmentInfo.OwnerShip.BYOD);
            device.setName(name);
            device.setType(RaspberrypiConstants.DEVICE_TYPE);
            enrolmentInfo.setOwner(APIUtil.getAuthenticatedUser());
            device.setEnrolmentInfo(enrolmentInfo);
            return APIUtil.getDeviceManagementService().enrollDevice(device);
        } catch (DeviceManagementException e) {
            return false;
        }
    }

    private ZipArchive createDownloadFile(String owner, String deviceName, String sketchType)
            throws DeviceManagementException, JWTClientException, APIManagerException,
                   UserStoreException {
        //create new device id
        String deviceId = shortUUID();
        boolean status = register(deviceId, deviceName);
        if (!status) {
            String msg = "Error occurred while registering the device with " + "id: " + deviceId + " owner:" + owner;
            throw new DeviceManagementException(msg);
        }
        if (apiApplicationKey == null) {
            String adminUsername = PrivilegedCarbonContext.getThreadLocalCarbonContext().getUserRealm().getRealmConfiguration().getAdminUserName();
            String tenantAdminDomainName = PrivilegedCarbonContext.getThreadLocalCarbonContext().getTenantDomain();
            String applicationUsername = PrivilegedCarbonContext.getThreadLocalCarbonContext().getUserRealm()
                    .getRealmConfiguration().getAdminUserName() + "@" + PrivilegedCarbonContext
                    .getThreadLocalCarbonContext().getTenantDomain();
            APIManagementProviderService apiManagementProviderService = APIUtil.getAPIManagementProviderService();
            String[] tags = {RaspberrypiConstants.DEVICE_TYPE};
            try{
                PrivilegedCarbonContext.startTenantFlow();
                PrivilegedCarbonContext.getThreadLocalCarbonContext().setTenantDomain(tenantAdminDomainName);
                PrivilegedCarbonContext.getThreadLocalCarbonContext().setUsername(adminUsername);
                apiApplicationKey = apiManagementProviderService.generateAndRetrieveApplicationKeys(
                        RaspberrypiConstants.DEVICE_TYPE, tags, KEY_TYPE, applicationUsername, true,
                        RaspberrypiConstants.APIM_APPLICATION_TOKEN_VALIDITY_PERIOD);
            } finally {
                PrivilegedCarbonContext.endTenantFlow();
            }
        }
        JWTClient jwtClient = APIUtil.getJWTClientManagerService().getJWTClient();
        String scopes = " device_" + deviceId;
        AccessTokenInfo accessTokenInfo = jwtClient.getAccessToken(apiApplicationKey.getConsumerKey(),
                                                                   apiApplicationKey.getConsumerSecret(), owner, scopes);
        //create token
        String accessToken = accessTokenInfo.getAccessToken();
        String refreshToken = accessTokenInfo.getRefreshToken();
        ZipUtil ziputil = new ZipUtil();
        return ziputil.createZipFile(owner, APIUtil.getTenantDomainOftheUser(), sketchType,
                                                   deviceId, deviceName, accessToken, refreshToken, apiApplicationKey.toString());
    }

    private static String shortUUID() {
        UUID uuid = UUID.randomUUID();
        long l = ByteBuffer.wrap(uuid.toString().getBytes(StandardCharsets.UTF_8)).getLong();
        return Long.toString(l, Character.MAX_RADIX);
    }
}
