/**
 * 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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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. See accompanying LICENSE file.
 */

package org.apache.hadoop.yarn.submarine.client.cli;

import com.google.common.annotations.VisibleForTesting;
import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.GnuParser;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;
import org.apache.commons.io.FileUtils;
import org.apache.hadoop.yarn.api.records.ApplicationId;
import org.apache.hadoop.yarn.exceptions.YarnException;
import org.apache.hadoop.yarn.submarine.client.cli.param.ParametersHolder;
import org.apache.hadoop.yarn.submarine.client.cli.param.RunJobParameters;
import org.apache.hadoop.yarn.submarine.client.cli.param.RunJobParameters.UnderscoreConverterPropertyUtils;
import org.apache.hadoop.yarn.submarine.client.cli.param.yaml.YamlConfigFile;
import org.apache.hadoop.yarn.submarine.client.cli.param.yaml.YamlParseException;
import org.apache.hadoop.yarn.submarine.common.ClientContext;
import org.apache.hadoop.yarn.submarine.common.exception.SubmarineException;
import org.apache.hadoop.yarn.submarine.runtimes.common.JobMonitor;
import org.apache.hadoop.yarn.submarine.runtimes.common.JobSubmitter;
import org.apache.hadoop.yarn.submarine.runtimes.common.StorageKeyConstants;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.yaml.snakeyaml.Yaml;
import org.yaml.snakeyaml.constructor.Constructor;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

public class RunJobCli extends AbstractCli {
  private static final Logger LOG =
      LoggerFactory.getLogger(RunJobCli.class);
  private static final String YAML_PARSE_FAILED = "Failed to parse " +
      "YAML config";

  private Options options;
  private RunJobParameters parameters = new RunJobParameters();

  private JobSubmitter jobSubmitter;
  private JobMonitor jobMonitor;

  public RunJobCli(ClientContext cliContext) {
    this(cliContext, cliContext.getRuntimeFactory().getJobSubmitterInstance(),
        cliContext.getRuntimeFactory().getJobMonitorInstance());
  }

  @VisibleForTesting
  RunJobCli(ClientContext cliContext, JobSubmitter jobSubmitter,
      JobMonitor jobMonitor) {
    super(cliContext);
    this.options = generateOptions();
    this.jobSubmitter = jobSubmitter;
    this.jobMonitor = jobMonitor;
  }

  public void printUsages() {
    new HelpFormatter().printHelp("job run", options);
  }

  private Options generateOptions() {
    Options options = new Options();
    options.addOption(CliConstants.YAML_CONFIG, true,
        "Config file (in YAML format)");
    options.addOption(CliConstants.NAME, true, "Name of the job");
    options.addOption(CliConstants.INPUT_PATH, true,
        "Input of the job, could be local or other FS directory");
    options.addOption(CliConstants.CHECKPOINT_PATH, true,
        "Training output directory of the job, "
            + "could be local or other FS directory. This typically includes "
            + "checkpoint files and exported model ");
    options.addOption(CliConstants.SAVED_MODEL_PATH, true,
        "Model exported path (savedmodel) of the job, which is needed when "
            + "exported model is not placed under ${checkpoint_path}"
            + "could be local or other FS directory. This will be used to serve.");
    options.addOption(CliConstants.N_WORKERS, true,
        "Number of worker tasks of the job, by default it's 1");
    options.addOption(CliConstants.N_PS, true,
        "Number of PS tasks of the job, by default it's 0");
    options.addOption(CliConstants.WORKER_RES, true,
        "Resource of each worker, for example "
            + "memory-mb=2048,vcores=2,yarn.io/gpu=2");
    options.addOption(CliConstants.PS_RES, true,
        "Resource of each PS, for example "
            + "memory-mb=2048,vcores=2,yarn.io/gpu=2");
    options.addOption(CliConstants.DOCKER_IMAGE, true, "Docker image name/tag");
    options.addOption(CliConstants.QUEUE, true,
        "Name of queue to run the job, by default it uses default queue");
    options.addOption(CliConstants.TENSORBOARD, false,
        "Should we run TensorBoard"
            + " for this job? By default it's disabled");
    options.addOption(CliConstants.TENSORBOARD_RESOURCES, true,
        "Specify resources of Tensorboard, by default it is "
            + CliConstants.TENSORBOARD_DEFAULT_RESOURCES);
    options.addOption(CliConstants.TENSORBOARD_DOCKER_IMAGE, true,
        "Specify Tensorboard docker image. when this is not "
            + "specified, Tensorboard " + "uses --" + CliConstants.DOCKER_IMAGE
            + " as default.");
    options.addOption(CliConstants.WORKER_LAUNCH_CMD, true,
        "Commandline of worker, arguments will be "
            + "directly used to launch the worker");
    options.addOption(CliConstants.PS_LAUNCH_CMD, true,
        "Commandline of worker, arguments will be "
            + "directly used to launch the PS");
    options.addOption(CliConstants.ENV, true,
        "Common environment variable of worker/ps");
    options.addOption(CliConstants.VERBOSE, false,
        "Print verbose log for troubleshooting");
    options.addOption(CliConstants.WAIT_JOB_FINISH, false,
        "Specified when user want to wait the job finish");
    options.addOption(CliConstants.PS_DOCKER_IMAGE, true,
        "Specify docker image for PS, when this is not specified, PS uses --"
            + CliConstants.DOCKER_IMAGE + " as default.");
    options.addOption(CliConstants.WORKER_DOCKER_IMAGE, true,
        "Specify docker image for WORKER, when this is not specified, WORKER "
            + "uses --" + CliConstants.DOCKER_IMAGE + " as default.");
    options.addOption(CliConstants.QUICKLINK, true, "Specify quicklink so YARN"
        + "web UI shows link to given role instance and port. When "
        + "--tensorboard is specified, quicklink to tensorboard instance will "
        + "be added automatically. The format of quick link is: "
        + "Quick_link_label=http(or https)://role-name:port. For example, "
        + "if want to link to first worker's 7070 port, and text of quicklink "
        + "is Notebook_UI, user need to specify --quicklink "
        + "Notebook_UI=https://master-0:7070");
    options.addOption(CliConstants.LOCALIZATION, true, "Specify"
        + " localization to make remote/local file/directory available to"
        + " all container(Docker)."
        + " Argument format is \"RemoteUri:LocalFilePath[:rw] \" (ro"
        + " permission is not supported yet)"
        + " The RemoteUri can be a file or directory in local or"
        + " HDFS or s3 or abfs or http .etc."
        + " The LocalFilePath can be absolute or relative."
        + " If it's a relative path, it'll be"
        + " under container's implied working directory"
        + " but sub directory is not supported yet."
        + " This option can be set mutiple times."
        + " Examples are \n"
        + "-localization \"hdfs:///user/yarn/mydir2:/opt/data\"\n"
        + "-localization \"s3a:///a/b/myfile1:./\"\n"
        + "-localization \"https:///a/b/myfile2:./myfile\"\n"
        + "-localization \"/user/yarn/mydir3:/opt/mydir3\"\n"
        + "-localization \"./mydir1:.\"\n");
    options.addOption(CliConstants.KEYTAB, true, "Specify keytab used by the " +
        "job under security environment");
    options.addOption(CliConstants.PRINCIPAL, true, "Specify principal used " +
        "by the job under security environment");
    options.addOption(CliConstants.DISTRIBUTE_KEYTAB, false, "Distribute " +
        "local keytab to cluster machines for service authentication. If not " +
        "specified, pre-distributed keytab of which path specified by" +
        " parameter" + CliConstants.KEYTAB + " on cluster machines will be " +
        "used");
    options.addOption("h", "help", false, "Print help");
    options.addOption("insecure", false, "Cluster is not Kerberos enabled.");
    options.addOption("conf", true,
        "User specified configuration, as key=val pairs.");
    return options;
  }

  private void replacePatternsInParameters() throws IOException {
    if (parameters.getPSLaunchCmd() != null && !parameters.getPSLaunchCmd()
        .isEmpty()) {
      String afterReplace = CliUtils.replacePatternsInLaunchCommand(
          parameters.getPSLaunchCmd(), parameters,
          clientContext.getRemoteDirectoryManager());
      parameters.setPSLaunchCmd(afterReplace);
    }

    if (parameters.getWorkerLaunchCmd() != null && !parameters
        .getWorkerLaunchCmd().isEmpty()) {
      String afterReplace = CliUtils.replacePatternsInLaunchCommand(
          parameters.getWorkerLaunchCmd(), parameters,
          clientContext.getRemoteDirectoryManager());
      parameters.setWorkerLaunchCmd(afterReplace);
    }
  }

  private void parseCommandLineAndGetRunJobParameters(String[] args)
      throws ParseException, IOException, YarnException {
    try {
      // Do parsing
      GnuParser parser = new GnuParser();
      CommandLine cli = parser.parse(options, args);
      ParametersHolder parametersHolder = createParametersHolder(cli);
      parameters.updateParameters(parametersHolder, clientContext);
    } catch (ParseException e) {
      LOG.error("Exception in parse: {}", e.getMessage());
      printUsages();
      throw e;
    }

    // Set default job dir / saved model dir, etc.
    setDefaultDirs();

    // replace patterns
    replacePatternsInParameters();
  }

  private ParametersHolder createParametersHolder(CommandLine cli) {
    String yamlConfigFile =
        cli.getOptionValue(CliConstants.YAML_CONFIG);
    if (yamlConfigFile != null) {
      YamlConfigFile yamlConfig = readYamlConfigFile(yamlConfigFile);
      if (yamlConfig == null) {
        throw new YamlParseException(String.format(
            YAML_PARSE_FAILED + ", file is empty: %s", yamlConfigFile));
      } else if (yamlConfig.getConfigs() == null) {
        throw new YamlParseException(String.format(YAML_PARSE_FAILED +
            ", config section should be defined, but it cannot be found in " +
            "YAML file '%s'!", yamlConfigFile));
      }
      LOG.info("Using YAML configuration!");
      return ParametersHolder.createWithCmdLineAndYaml(cli, yamlConfig);
    } else {
      LOG.info("Using CLI configuration!");
      return ParametersHolder.createWithCmdLine(cli);
    }
  }

  private YamlConfigFile readYamlConfigFile(String filename) {
    Constructor constructor = new Constructor(YamlConfigFile.class);
    constructor.setPropertyUtils(new UnderscoreConverterPropertyUtils());
    try {
      LOG.info("Reading YAML configuration from file: {}", filename);
      Yaml yaml = new Yaml(constructor);
      return yaml.loadAs(FileUtils.openInputStream(new File(filename)),
          YamlConfigFile.class);
    } catch (FileNotFoundException e) {
      logExceptionOfYamlParse(filename, e);
      throw new YamlParseException(YAML_PARSE_FAILED +
          ", file does not exist!");
    } catch (Exception e) {
      logExceptionOfYamlParse(filename, e);
      throw new YamlParseException(
          String.format(YAML_PARSE_FAILED + ", details: %s", e.getMessage()));
    }
  }

  private void logExceptionOfYamlParse(String filename, Exception e) {
    LOG.error(String.format("Exception while parsing YAML file %s", filename),
        e);
  }

  private void setDefaultDirs() throws IOException {
    // Create directories if needed
    String jobDir = parameters.getCheckpointPath();
    if (null == jobDir) {
      if (parameters.getNumWorkers() > 0) {
        jobDir = clientContext.getRemoteDirectoryManager().getJobCheckpointDir(
            parameters.getName(), true).toString();
      } else {
        // when #workers == 0, it means we only launch TB. In that case,
        // point job dir to root dir so all job's metrics will be shown.
        jobDir = clientContext.getRemoteDirectoryManager().getUserRootFolder()
            .toString();
      }
      parameters.setCheckpointPath(jobDir);
    }

    if (parameters.getNumWorkers() > 0) {
      // Only do this when #worker > 0
      String savedModelDir = parameters.getSavedModelPath();
      if (null == savedModelDir) {
        savedModelDir = jobDir;
        parameters.setSavedModelPath(savedModelDir);
      }
    }
  }

  private void storeJobInformation(String jobName, ApplicationId applicationId,
      String[] args) throws IOException {
    Map<String, String> jobInfo = new HashMap<>();
    jobInfo.put(StorageKeyConstants.JOB_NAME, jobName);
    jobInfo.put(StorageKeyConstants.APPLICATION_ID, applicationId.toString());

    if (parameters.getCheckpointPath() != null) {
      jobInfo.put(StorageKeyConstants.CHECKPOINT_PATH,
          parameters.getCheckpointPath());
    }
    if (parameters.getInputPath() != null) {
      jobInfo.put(StorageKeyConstants.INPUT_PATH,
          parameters.getInputPath());
    }
    if (parameters.getSavedModelPath() != null) {
      jobInfo.put(StorageKeyConstants.SAVED_MODEL_PATH,
          parameters.getSavedModelPath());
    }

    String joinedArgs = String.join(" ", args);
    jobInfo.put(StorageKeyConstants.JOB_RUN_ARGS, joinedArgs);
    clientContext.getRuntimeFactory().getSubmarineStorage().addNewJob(jobName,
        jobInfo);
  }

  @Override
  public int run(String[] args)
      throws ParseException, IOException, YarnException, SubmarineException {
    if (CliUtils.argsForHelp(args)) {
      printUsages();
      return 0;
    }

    parseCommandLineAndGetRunJobParameters(args);
    ApplicationId applicationId = this.jobSubmitter.submitJob(parameters);
    storeJobInformation(parameters.getName(), applicationId, args);
    if (parameters.isWaitJobFinish()) {
      this.jobMonitor.waitTrainingFinal(parameters.getName());
    }

    return 0;
  }

  @VisibleForTesting
  public JobSubmitter getJobSubmitter() {
    return jobSubmitter;
  }

  @VisibleForTesting
  public RunJobParameters getRunJobParameters() {
    return parameters;
  }
}
