/*
 * 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.hudi.sink.utils;

import lombok.Getter;
import lombok.Setter;
import org.apache.flink.api.common.ExecutionConfig;
import org.apache.flink.api.common.state.KeyedStateStore;
import org.apache.flink.metrics.groups.OperatorMetricGroup;
import org.apache.flink.metrics.groups.UnregisteredMetricsGroup;
import org.apache.flink.runtime.jobgraph.OperatorID;
import org.apache.flink.runtime.memory.MemoryManager;
import org.apache.flink.runtime.operators.testutils.MockEnvironment;
import org.apache.flink.runtime.operators.testutils.MockEnvironmentBuilder;
import org.apache.flink.streaming.api.operators.AbstractStreamOperator;
import org.apache.flink.streaming.api.operators.StreamingRuntimeContext;
import org.apache.flink.streaming.runtime.tasks.ProcessingTimeService;
import org.apache.flink.streaming.runtime.tasks.TestProcessingTimeService;

import java.util.HashMap;
import java.util.Map;

/**
 * Mock {@link StreamingRuntimeContext} to use in tests.
 *
 * <p>NOTE: Adapted from Apache Flink, the MockStreamOperator is modified to support MapState.
 */
@Getter
public class MockStreamingRuntimeContext extends StreamingRuntimeContext {

  private final boolean isCheckpointingEnabled;

  private final MockTaskInfo taskInfo;

  public MockStreamingRuntimeContext(
      boolean isCheckpointingEnabled,
      int numParallelSubtasks,
      int subtaskIndex) {

    this(isCheckpointingEnabled, numParallelSubtasks, subtaskIndex, new MockEnvironmentBuilder()
        .setTaskName("mockTask")
        .setManagedMemorySize(4 * MemoryManager.DEFAULT_PAGE_SIZE)
        .build());
  }

  public MockStreamingRuntimeContext(
      boolean isCheckpointingEnabled,
      int numParallelSubtasks,
      int subtaskIndex,
      MockEnvironment environment) {

    super(new MockStreamOperator(), environment, new HashMap<>());

    this.isCheckpointingEnabled = isCheckpointingEnabled;
    this.taskInfo = new MockTaskInfo(numParallelSubtasks, subtaskIndex, 0);
  }

  public MockStreamingRuntimeContext(
      boolean isCheckpointingEnabled,
      int numParallelSubtasks,
      int subtaskIndex,
      MockEnvironment environment,
      ExecutionConfig executionConfig) {

    super(new MockStreamOperator(executionConfig), environment, new HashMap<>());

    this.isCheckpointingEnabled = isCheckpointingEnabled;
    this.taskInfo = new MockTaskInfo(numParallelSubtasks, subtaskIndex, 0);
  }

  public int getIndexOfThisSubtask() {
    return taskInfo.getIndexOfThisSubtask();
  }

  public int getNumberOfParallelSubtasks() {
    return taskInfo.getNumberOfParallelSubtasks();
  }

  public int getAttemptNumber() {
    return taskInfo.getAttemptNumber();
  }

  public void setAttemptNumber(int attemptNumber) {
    this.taskInfo.setAttemptNumber(attemptNumber);
  }

  private static class MockStreamOperator extends AbstractStreamOperator<Integer> {
    private static final long serialVersionUID = -1153976702711944427L;

    private transient TestProcessingTimeService testProcessingTimeService;
    private final transient ExecutionConfig executionConfig;

    @Setter
    private transient Object currentKey;
    private final transient Map<Object, MockKeyedStateStore> mockKeyedStateStoreMap = new HashMap<>();

    MockStreamOperator() {
      this(new ExecutionConfig());
    }

    MockStreamOperator(ExecutionConfig executionConfig) {
      this.executionConfig = executionConfig;
    }

    @Override
    public ExecutionConfig getExecutionConfig() {
      return executionConfig;
    }

    @Override
    public OperatorID getOperatorID() {
      return new OperatorID();
    }

    @Override
    public ProcessingTimeService getProcessingTimeService() {
      if (testProcessingTimeService == null) {
        testProcessingTimeService = new TestProcessingTimeService();
      }
      return testProcessingTimeService;
    }

    @Override
    public KeyedStateStore getKeyedStateStore() {
      return currentKey != null ? mockKeyedStateStoreMap.computeIfAbsent(currentKey, k -> new MockKeyedStateStore()) : null;
    }
  }

  @Override
  public OperatorMetricGroup getMetricGroup() {
    return UnregisteredMetricsGroup.createOperatorMetricGroup();
  }
}
