// Copyright (C) 2019 The Android Open Source Project
//
// 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.gerrit.server.index;

import com.google.auto.value.AutoValue;
import com.google.errorprone.annotations.FormatMethod;
import java.util.Optional;

/** Structured result of a staleness check. */
@AutoValue
public abstract class StalenessCheckResult {

  public static StalenessCheckResult notStale() {
    return new AutoValue_StalenessCheckResult(false, Optional.empty());
  }

  public static StalenessCheckResult stale(String reason) {
    return new AutoValue_StalenessCheckResult(true, Optional.of(reason));
  }

  @FormatMethod
  public static StalenessCheckResult stale(String reason, Object... args) {
    return stale(String.format(reason, args));
  }

  public abstract boolean isStale();

  public abstract Optional<String> reason();
}