// Copyright 2022 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.config;

import static com.google.common.collect.ImmutableSet.toImmutableSet;
import static java.util.Arrays.stream;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.devtools.common.options.OptionDefinition;
import com.google.devtools.common.options.OptionMetadataTag;
import com.google.devtools.common.options.OptionsParser;

/** Stores information about a build option gathered via reflection. */
public final class OptionInfo {
  private final Class<? extends FragmentOptions> optionClass;
  private final OptionDefinition definition;

  private OptionInfo(Class<? extends FragmentOptions> optionClass, OptionDefinition definition) {
    this.optionClass = optionClass;
    this.definition = definition;
  }

  public Class<? extends FragmentOptions> getOptionClass() {
    return optionClass;
  }

  public OptionDefinition getDefinition() {
    return definition;
  }

  public boolean hasOptionMetadataTag(OptionMetadataTag tag) {
    return stream(getDefinition().getOptionMetadataTags()).anyMatch(tag::equals);
  }

  /** For all the options in the BuildOptions, build a map from option name to its information. */
  public static ImmutableMap<String, OptionInfo> buildMapFrom(BuildOptions buildOptions) {
    ImmutableMap.Builder<String, OptionInfo> builder = new ImmutableMap.Builder<>();

    ImmutableSet<Class<? extends FragmentOptions>> optionClasses =
        buildOptions.getNativeOptions().stream()
            .map(FragmentOptions::getClass)
            .collect(toImmutableSet());

    for (Class<? extends FragmentOptions> optionClass : optionClasses) {
      ImmutableList<OptionDefinition> optionDefinitions =
          OptionsParser.getOptionDefinitions(optionClass);
      for (OptionDefinition def : optionDefinitions) {
        String optionName = def.getOptionName();
        builder.put(optionName, new OptionInfo(optionClass, def));
      }
    }

    return builder.build();
  }
}