/**
 * 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.hadoop.hdfs.server.namenode.snapshot;

import java.util.ArrayList;

import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.fs.permission.PermissionStatus;
import org.apache.hadoop.hdfs.protocol.Block;
import org.apache.hadoop.hdfs.protocol.BlockStoragePolicy;
import org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo;
import org.apache.hadoop.hdfs.server.blockmanagement.BlockInfoContiguous;
import org.apache.hadoop.hdfs.server.blockmanagement.BlockManager;
import org.apache.hadoop.hdfs.server.blockmanagement.BlockStoragePolicySuite;
import org.apache.hadoop.hdfs.server.namenode.INode;
import org.apache.hadoop.hdfs.server.namenode.INodeFile;
import org.apache.hadoop.hdfs.server.namenode.QuotaCounts;
import org.apache.hadoop.test.Whitebox;
import org.apache.hadoop.util.Lists;

import org.junit.jupiter.api.Test;
import org.mockito.Mockito;

import static org.apache.hadoop.fs.StorageType.DISK;
import static org.apache.hadoop.fs.StorageType.SSD;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.mockito.Mockito.anyByte;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.spy;
import static org.mockito.Mockito.when;

public class TestFileWithSnapshotFeature {
  private static final int BLOCK_SIZE = 1024;
  private static final short REPL_3 = 3;
  private static final short REPL_1 = 1;

  @Test
  public void testUpdateQuotaAndCollectBlocks() {
    FileDiffList diffs = new FileDiffList();
    FileWithSnapshotFeature sf = new FileWithSnapshotFeature(diffs);
    FileDiff diff = mock(FileDiff.class);
    BlockStoragePolicySuite bsps = mock(BlockStoragePolicySuite.class);
    BlockStoragePolicy bsp = mock(BlockStoragePolicy.class);
    BlockInfo[] blocks = new BlockInfo[] {
        new BlockInfoContiguous(new Block(1, BLOCK_SIZE, 1), REPL_1)
    };
    BlockManager bm = mock(BlockManager.class);

    // No snapshot
    INodeFile inodeFileObj = createMockFile(REPL_1);
    INodeFile file = spy(inodeFileObj);
    when(file.getFileWithSnapshotFeature()).thenReturn(sf);
    when(file.getBlocks()).thenReturn(blocks);
    when(file.getStoragePolicyID()).thenReturn((byte) 1);
    Whitebox.setInternalState(file, "header", (long) REPL_1 << 48);
    when(file.getPreferredBlockReplication()).thenReturn(REPL_1);

    when(bsps.getPolicy(anyByte())).thenReturn(bsp);
    INode.BlocksMapUpdateInfo collectedBlocks = mock(
        INode.BlocksMapUpdateInfo.class);
    ArrayList<INode> removedINodes = new ArrayList<>();
    INode.ReclaimContext ctx = new INode.ReclaimContext(
        bsps, collectedBlocks, removedINodes, null);
    sf.updateQuotaAndCollectBlocks(ctx, file, diff);
    QuotaCounts counts = ctx.quotaDelta().getCountsCopy();
    assertEquals(0, counts.getStorageSpace());
    assertTrue(counts.getTypeSpaces().allLessOrEqual(0));

    // INode only exists in the snapshot
    INodeFile snapshotINode = mock(INodeFile.class);
    Whitebox.setInternalState(snapshotINode, "header", (long) REPL_3 << 48);
    Whitebox.setInternalState(diff, "snapshotINode", snapshotINode);
    when(diff.getSnapshotINode()).thenReturn(snapshotINode);

    when(bsp.chooseStorageTypes(REPL_1))
        .thenReturn(Lists.newArrayList(SSD));
    when(bsp.chooseStorageTypes(REPL_3))
        .thenReturn(Lists.newArrayList(DISK));
    blocks[0].setReplication(REPL_3);
    sf.updateQuotaAndCollectBlocks(ctx, file, diff);
    counts = ctx.quotaDelta().getCountsCopy();
    assertEquals((REPL_3 - REPL_1) * BLOCK_SIZE,
        counts.getStorageSpace());
    assertEquals(BLOCK_SIZE, counts.getTypeSpaces().get(DISK));
    assertEquals(-BLOCK_SIZE, counts.getTypeSpaces().get(SSD));
  }

  private INodeFile createMockFile(short replication) {
    BlockInfo[] blocks = new BlockInfo[] {};
    PermissionStatus perm = new PermissionStatus("foo", "bar", FsPermission
        .createImmutable((short) 0x1ff));
    INodeFile iNodeFile =
        new INodeFile(1, new byte[0], perm, 0, 0, blocks, replication,
            BLOCK_SIZE);
    return iNodeFile;
  }

  /**
   * Test update quota with same blocks.
   */
  @Test
  public void testUpdateQuotaDistinctBlocks() {
    BlockStoragePolicySuite bsps = mock(BlockStoragePolicySuite.class);
    BlockStoragePolicy bsp = mock(BlockStoragePolicy.class);
    BlockInfo[] blocks = new BlockInfo[] {
        new BlockInfoContiguous(new Block(1, BLOCK_SIZE, 1), REPL_3) };

    INodeFile inodeFileObj = createMockFile(REPL_1);
    INodeFile file = spy(inodeFileObj);
    when(file.getBlocks()).thenReturn(blocks);
    when(file.getStoragePolicyID()).thenReturn((byte) 1);
    when(file.getPreferredBlockReplication()).thenReturn((short) 3);

    when(bsps.getPolicy(anyByte())).thenReturn(bsp);
    INode.BlocksMapUpdateInfo collectedBlocks =
        mock(INode.BlocksMapUpdateInfo.class);
    ArrayList<INode> removedINodes = new ArrayList<>();
    INode.ReclaimContext ctx =
        new INode.ReclaimContext(bsps, collectedBlocks, removedINodes, null);
    QuotaCounts counts = ctx.quotaDelta().getCountsCopy();
    INodeFile snapshotINode = mock(INodeFile.class);

    // add same blocks in file diff
    FileDiff diff1 = new FileDiff(0, snapshotINode, null, 0);
    FileDiff diff = Mockito.spy(diff1);
    Mockito.doReturn(blocks).when(diff).getBlocks();

    // removed file diff
    FileDiff removed = new FileDiff(0, snapshotINode, null, 0);

    // remaining file diffs
    FileDiffList diffs = new FileDiffList();
    diffs.addFirst(diff);
    FileWithSnapshotFeature sf = new FileWithSnapshotFeature(diffs);

    // update quota and collect same blocks in file and file diff
    when(file.getFileWithSnapshotFeature()).thenReturn(sf);
    sf.updateQuotaAndCollectBlocks(ctx, file, removed);
    counts = ctx.quotaDelta().getCountsCopy();
    assertEquals(0, counts.getStorageSpace());

    // different blocks in file and file's diff and in removed diff
    BlockInfo[] blocks1 = new BlockInfo[] {
        new BlockInfoContiguous(new Block(2, BLOCK_SIZE, 1), REPL_3) };
    Mockito.doReturn(blocks1).when(diff).getBlocks();
    // remaining file diffs
    FileDiffList diffs1 = new FileDiffList();
    diffs1.addFirst(diff);
    FileWithSnapshotFeature sf1 = new FileWithSnapshotFeature(diffs1);
    when(file.getFileWithSnapshotFeature()).thenReturn(sf1);
    BlockInfo[] removedBlocks = new BlockInfo[] {
        new BlockInfoContiguous(new Block(3, BLOCK_SIZE, 1), REPL_3) };
    FileDiff removed1 = new FileDiff(0, snapshotINode, null, 1024);
    removed1.setBlocks(removedBlocks);
    INode.ReclaimContext ctx1 =
        new INode.ReclaimContext(bsps, collectedBlocks, removedINodes, null);
    sf1.updateQuotaAndCollectBlocks(ctx1, file, removed1);
    counts = ctx1.quotaDelta().getCountsCopy();
    assertEquals(3072, counts.getStorageSpace());

    // same blocks in file and removed diff
    removed1 = new FileDiff(0, snapshotINode, null, 1024);
    removed1.setBlocks(blocks);
    INode.ReclaimContext ctx2 =
        new INode.ReclaimContext(bsps, collectedBlocks, removedINodes, null);
    sf1.updateQuotaAndCollectBlocks(ctx2, file, removed1);
    counts = ctx2.quotaDelta().getCountsCopy();
    assertEquals(0, counts.getStorageSpace());
  }
}
