// Copyright 2014 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.skyframe;

import com.google.devtools.build.lib.actions.ActionLookupKey;
import com.google.devtools.build.lib.actions.Actions;
import com.google.devtools.build.lib.actions.Artifact;
import com.google.devtools.build.lib.actions.BasicActionLookupValue;
import com.google.devtools.build.lib.analysis.WorkspaceStatusAction;
import com.google.devtools.build.lib.cmdline.Label;
import com.google.devtools.build.lib.skyframe.serialization.autocodec.SerializationConstant;
import com.google.devtools.build.skyframe.SkyFunctionName;
import javax.annotation.Nullable;

/**
 * Value that stores the workspace status artifacts and their generating action. There should be
 * only one of these values in the graph at any time.
 */
// TODO(bazel-team): This seems to be superfluous now, but it cannot be removed without making
// PrecomputedValue public instead of package-private
public class WorkspaceStatusValue extends BasicActionLookupValue {
  private final Artifact stableArtifact;
  private final Artifact volatileArtifact;

  // There should only ever be one BuildInfo value in the graph.
  @SerializationConstant public static final BuildInfoKey BUILD_INFO_KEY = new BuildInfoKey();

  WorkspaceStatusValue(
      Artifact stableArtifact,
      Artifact volatileArtifact,
      WorkspaceStatusAction workspaceStatusAction) {
    super(Actions.GeneratingActions.fromSingleAction(workspaceStatusAction, BUILD_INFO_KEY));
    this.stableArtifact = stableArtifact;
    this.volatileArtifact = volatileArtifact;
  }

  public Artifact getStableArtifact() {
    return stableArtifact;
  }

  public Artifact getVolatileArtifact() {
    return volatileArtifact;
  }

  /** {@link com.google.devtools.build.skyframe.SkyKey} for {@link WorkspaceStatusValue}. */
  public static final class BuildInfoKey implements ActionLookupKey {
    private BuildInfoKey() {}

    @Override
    public SkyFunctionName functionName() {
      return SkyFunctions.BUILD_INFO;
    }

    @Nullable
    @Override
    public Label getLabel() {
      return null;
    }

    @Nullable
    @Override
    public BuildConfigurationKey getConfigurationKey() {
      return null;
    }
  }
}