/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF 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.apache.nemo.common.test;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.StringJoiner;

/**
 * Argument builder.
 */
public final class ArgBuilder {
  private List<List<String>> args;

  /**
   * Constructor with default values.
   */
  public ArgBuilder() {
    this.args = new ArrayList<>();
  }

  /**
   * @param jobId job id.
   * @return builder with the job id.
   */
  public ArgBuilder addJobId(final String jobId) {
    args.add(Arrays.asList("-job_id", jobId));
    return this;
  }

  /**
   * @param main user main class.
   * @return builder with the user main class.
   */
  public ArgBuilder addUserMain(final String main) {
    args.add(Arrays.asList("-user_main", main));
    return this;
  }

  /**
   * @param userArgs user arguments.
   * @return builder with the user arguments.
   */
  public ArgBuilder addUserArgs(final String... userArgs) {
    final StringJoiner joiner = new StringJoiner(" ");
    Arrays.stream(userArgs).forEach(joiner::add);
    args.add(Arrays.asList("-user_args", joiner.toString()));
    return this;
  }

  /**
   * @param policy optimization policy.
   * @return builder with the optimization policy.
   */
  public ArgBuilder addOptimizationPolicy(final String policy) {
    args.add(Arrays.asList("-optimization_policy", policy));
    return this;
  }

  /**
   * @param maxAttempt maximum number of the attempts
   * @return builder with the maximum number of the attempts
   */
  public ArgBuilder addMaxTaskAttempt(final int maxAttempt) {
    args.add(Arrays.asList("-max_task_attempt", String.valueOf(maxAttempt)));
    return this;
  }

  /**
   * @param directory directory to save the DAG.
   * @return builder with the DAG directory.
   */
  public ArgBuilder addDAGDirectory(final String directory) {
    args.add(Arrays.asList("-dag_dir", directory));
    return this;
  }

  /**
   * @param executorJsonFileName the name of the executor resource file to use.
   * @return builder with the executor resource file.
   */
  public ArgBuilder addResourceJson(final String executorJsonFileName) {
    args.add(Arrays.asList("-executor_json", executorJsonFileName));
    return this;
  }

  /**
   * @param schedulerName scheduler.
   * @return builder with the scheduler.
   */
  public ArgBuilder addScheduler(final String schedulerName) {
    args.add(Arrays.asList("-scheduler_impl_class_name", schedulerName));
    return this;
  }

  /**
   * @return the built arguments.
   */
  public String[] build() {
    return args.stream().flatMap(List::stream).toArray(String[]::new);
  }
}