// Copyright 2017 The Bazel Authors. All rights reserved.
//
// 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
//
// 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 com.google.devtools.build.lib.analysis;

import static com.google.common.collect.Iterables.size;
import static com.google.devtools.build.lib.analysis.OutputGroupProvider.HIDDEN_OUTPUT_GROUP_PREFIX;
import static com.google.devtools.build.lib.analysis.TopLevelArtifactHelper.getAllArtifactsToBuild;
import static com.google.devtools.build.lib.util.Preconditions.checkNotNull;
import static java.util.Arrays.asList;
import static org.junit.Assert.assertEquals;

import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSortedSet;
import com.google.devtools.build.lib.actions.Artifact;
import com.google.devtools.build.lib.actions.Root;
import com.google.devtools.build.lib.analysis.TopLevelArtifactHelper.ArtifactsInOutputGroup;
import com.google.devtools.build.lib.analysis.TopLevelArtifactHelper.ArtifactsToBuild;
import com.google.devtools.build.lib.collect.nestedset.NestedSet;
import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
import com.google.devtools.build.lib.collect.nestedset.Order;
import com.google.devtools.build.lib.testutil.Scratch;
import com.google.devtools.build.lib.util.Pair;
import com.google.devtools.build.lib.vfs.Path;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/** Tests for {@link TopLevelArtifactHelper}. */
@RunWith(JUnit4.class)
public class TopLevelArtifactHelperTest {

  private TopLevelArtifactContext ctx;
  private OutputGroupProvider groupProvider;

  private Path path;
  private Root root;
  private int artifactIdx;

  @Before
  public final void setRootDir() throws Exception {
    Scratch scratch = new Scratch();
    path = scratch.dir("/foo");
    root = Root.asDerivedRoot(scratch.dir("/"));
  }

  private void setup(Iterable<Pair<String, Integer>> groupArtifacts) {
    ImmutableSortedSet.Builder<String> setBuilder = ImmutableSortedSet.naturalOrder();
    ImmutableMap.Builder<String, NestedSet<Artifact>> mapBuilder = ImmutableMap.builder();
    for (Pair<String, Integer> groupArtifact : groupArtifacts) {
      setBuilder.add(checkNotNull(groupArtifact.getFirst()));
      mapBuilder.put(
          groupArtifact.getFirst(), newArtifacts(checkNotNull(groupArtifact.getSecond())));
    }
    ctx = new TopLevelArtifactContext(false, setBuilder.build());
    groupProvider = new OutputGroupProvider(mapBuilder.build());
  }

  @Test
  public void artifactsShouldBeSeparateByGroup() {
    setup(asList(Pair.of("foo", 3), Pair.of("bar", 2)));

    ArtifactsToBuild allArtifacts = getAllArtifactsToBuild(groupProvider, null, ctx);
    assertEquals(5, size(allArtifacts.getAllArtifacts()));
    assertEquals(5, size(allArtifacts.getImportantArtifacts()));

    NestedSet<ArtifactsInOutputGroup> artifactsByGroup =
        allArtifacts.getAllArtifactsByOutputGroup();
    // Two groups
    assertEquals(2, size(artifactsByGroup));

    for (ArtifactsInOutputGroup artifacts : artifactsByGroup) {
      String outputGroup = artifacts.getOutputGroup();
      if ("foo".equals(outputGroup)) {
        assertEquals(3, size(artifacts.getArtifacts()));
      } else if ("bar".equals(outputGroup)) {
        assertEquals(2, size(artifacts.getArtifacts()));
      }
    }
  }

  @Test
  public void emptyGroupsShouldBeIgnored() {
    setup(asList(Pair.of("foo", 1), Pair.of("bar", 0)));

    ArtifactsToBuild allArtifacts = getAllArtifactsToBuild(groupProvider, null, ctx);
    assertEquals(1, size(allArtifacts.getAllArtifacts()));
    assertEquals(1, size(allArtifacts.getImportantArtifacts()));

    NestedSet<ArtifactsInOutputGroup> artifactsByGroup =
        allArtifacts.getAllArtifactsByOutputGroup();
    // The bar list should not appear here, as it contains no artifacts.
    assertEquals(1, size(artifactsByGroup));
    assertEquals("foo", artifactsByGroup.toList().get(0).getOutputGroup());
  }

  @Test
  public void importantArtifacts() {
    setup(asList(Pair.of(HIDDEN_OUTPUT_GROUP_PREFIX + "notimportant", 1), Pair.of("important", 2)));

    ArtifactsToBuild allArtifacts = getAllArtifactsToBuild(groupProvider, null, ctx);
    assertEquals(3, size(allArtifacts.getAllArtifacts()));
    assertEquals(2, size(allArtifacts.getImportantArtifacts()));
  }

  private NestedSet<Artifact> newArtifacts(int num) {
    NestedSetBuilder<Artifact> builder = new NestedSetBuilder<>(Order.STABLE_ORDER);
    for (int i = 0; i < num; i++) {
      builder.add(newArtifact());
    }
    return builder.build();
  }

  private Artifact newArtifact() {
    return new Artifact(path.getRelative(Integer.toString(artifactIdx++)), root);
  }
}