/*
 * 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.beam.runners.dataflow.worker;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotSame;
import static org.junit.Assert.assertSame;

import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import java.io.Closeable;
import java.io.IOException;
import org.apache.beam.runners.dataflow.internal.IsmFormat.IsmRecordCoder;
import org.apache.beam.runners.dataflow.options.DataflowPipelineOptions;
import org.apache.beam.runners.dataflow.util.CloudObject;
import org.apache.beam.runners.dataflow.util.PropertyNames;
import org.apache.beam.runners.dataflow.worker.DataflowOperationContext.DataflowExecutionState;
import org.apache.beam.runners.dataflow.worker.profiler.ScopedProfiler.NoopProfileScope;
import org.apache.beam.runners.dataflow.worker.util.WorkerPropertyNames;
import org.apache.beam.sdk.coders.Coder;
import org.apache.beam.sdk.coders.StringUtf8Coder;
import org.apache.beam.sdk.coders.VarLongCoder;
import org.apache.beam.sdk.io.FileSystems;
import org.apache.beam.sdk.io.fs.ResourceId;
import org.apache.beam.sdk.options.PipelineOptionsFactory;
import org.apache.beam.sdk.transforms.windowing.GlobalWindow;
import org.apache.beam.sdk.util.WindowedValue;
import org.apache.beam.sdk.util.WindowedValue.WindowedValueCoder;
import org.junit.After;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.TemporaryFolder;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/** Tests for {@link IsmReaderFactory}. */
@RunWith(JUnit4.class)
public class IsmReaderFactoryTest {
  private DataflowPipelineOptions options;
  private Cache<Object, Object> logicalReferenceCache;
  private BatchModeExecutionContext executionContext;
  private Closeable stateCloseable;
  private DataflowOperationContext operationContext;

  @Rule public TemporaryFolder tmpFolder = new TemporaryFolder();

  @Before
  public void setUp() {
    options = PipelineOptionsFactory.as(DataflowPipelineOptions.class);
    logicalReferenceCache = CacheBuilder.newBuilder().weakValues().build();

    executionContext =
        BatchModeExecutionContext.forTesting(
            PipelineOptionsFactory.as(DataflowPipelineOptions.class),
            NameContextsForTests.nameContextForTest().stageName());

    DataflowExecutionState state =
        executionContext
            .getExecutionStateRegistry()
            .getState(
                NameContextsForTests.nameContextForTest(),
                "test",
                null /*container */,
                NoopProfileScope.NOOP);

    operationContext =
        executionContext.createOperationContext(NameContextsForTests.nameContextForTest());
    stateCloseable = executionContext.getExecutionStateTracker().enterState(state);
  }

  @After
  public void tearDown() throws IOException {
    stateCloseable.close();
  }

  @Test
  public void testFactory() throws Exception {
    WindowedValueCoder<?> coder =
        WindowedValue.getFullCoder(
            IsmRecordCoder.of(
                1, 0, ImmutableList.<Coder<?>>of(StringUtf8Coder.of()), VarLongCoder.of()),
            GlobalWindow.Coder.INSTANCE);

    String tmpFile = tmpFolder.newFile().getPath();
    ResourceId tmpResourceId = FileSystems.matchSingleFileSpec(tmpFile).resourceId();
    @SuppressWarnings("rawtypes")
    IsmReader<?> ismReader =
        (IsmReader)
            new IsmReaderFactory()
                .create(
                    createSpecForFilename(tmpFile),
                    coder,
                    options,
                    executionContext,
                    operationContext);
    assertEquals(coder.getValueCoder(), ismReader.getCoder());
    assertEquals(tmpResourceId, ismReader.getResourceId());
  }

  @Test
  public void testFactoryReturnsCachedInstance() throws Exception {
    Coder<?> coder =
        WindowedValue.getFullCoder(
            IsmRecordCoder.of(
                1, 0, ImmutableList.<Coder<?>>of(StringUtf8Coder.of()), VarLongCoder.of()),
            GlobalWindow.Coder.INSTANCE);

    String tmpFile = tmpFolder.newFile().getPath();
    String anotherTmpFile = tmpFolder.newFile().getPath();

    @SuppressWarnings("rawtypes")
    IsmReader<?> ismReader =
        (IsmReader)
            new IsmReaderFactory()
                .create(
                    createSpecForFilename(tmpFile),
                    coder,
                    options,
                    executionContext,
                    operationContext);
    assertSame(
        ismReader,
        new IsmReaderFactory()
            .create(
                createSpecForFilename(tmpFile),
                coder,
                options,
                executionContext,
                operationContext));
    assertNotSame(
        ismReader,
        new IsmReaderFactory()
            .create(
                createSpecForFilename(anotherTmpFile),
                coder,
                options,
                executionContext,
                operationContext));
  }

  private CloudObject createSpecForFilename(String filename) {
    return CloudObject.fromSpec(
        ImmutableMap.<String, Object>of(
            PropertyNames.OBJECT_TYPE_NAME, "IsmSource", WorkerPropertyNames.FILENAME, filename));
  }
}
