/*
 * Copyright 2016-present Facebook, Inc.
 *
 * 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.facebook.buck.cxx;

import static org.hamcrest.Matchers.hasItem;
import static org.junit.Assert.assertThat;

import com.facebook.buck.model.BuildTarget;
import com.facebook.buck.model.BuildTargetFactory;
import com.facebook.buck.rules.BuildContext;
import com.facebook.buck.rules.BuildRuleParams;
import com.facebook.buck.rules.BuildRuleResolver;
import com.facebook.buck.rules.DefaultTargetNodeToBuildRuleTransformer;
import com.facebook.buck.rules.FakeBuildContext;
import com.facebook.buck.rules.FakeBuildRuleParamsBuilder;
import com.facebook.buck.rules.FakeBuildableContext;
import com.facebook.buck.rules.FakeSourcePath;
import com.facebook.buck.rules.SourcePathResolver;
import com.facebook.buck.rules.SourcePathRuleFinder;
import com.facebook.buck.rules.TargetGraph;
import com.facebook.buck.step.Step;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Iterables;
import java.nio.file.Paths;
import java.util.Optional;
import org.junit.Test;

public class CxxPrecompiledHeaderTest {

  @Test
  public void generatesPchStepShouldUseCorrectLang() throws Exception {
    BuildTarget target = BuildTargetFactory.newInstance("//foo:bar");
    BuildRuleParams params = new FakeBuildRuleParamsBuilder(target).build();
    BuildRuleResolver resolver =
        new BuildRuleResolver(TargetGraph.EMPTY, new DefaultTargetNodeToBuildRuleTransformer());
    Preprocessor preprocessorSupportingPch =
        new GccPreprocessor(CxxPlatformUtils.DEFAULT_PLATFORM.getCpp().resolve(resolver)) {
          @Override
          public boolean supportsPrecompiledHeaders() {
            return true;
          }
        };
    Compiler compiler = CxxPlatformUtils.DEFAULT_PLATFORM.getCxx().resolve(resolver);
    SourcePathResolver sourcePathResolver =
        new SourcePathResolver(new SourcePathRuleFinder(resolver));
    CxxPrecompiledHeader precompiledHeader =
        new CxxPrecompiledHeader(
            params,
            Paths.get("dir/foo.hash1.hash2.gch"),
            new PreprocessorDelegate(
                sourcePathResolver,
                CxxPlatformUtils.DEFAULT_COMPILER_DEBUG_PATH_SANITIZER,
                CxxPlatformUtils.DEFAULT_PLATFORM.getHeaderVerification(),
                Paths.get("./"),
                preprocessorSupportingPch,
                PreprocessorFlags.builder().build(),
                CxxDescriptionEnhancer.frameworkPathToSearchPath(
                    CxxPlatformUtils.DEFAULT_PLATFORM, sourcePathResolver),
                Optional.empty(),
                /* leadingIncludePaths */ Optional.empty()),
            new CompilerDelegate(
                sourcePathResolver,
                CxxPlatformUtils.DEFAULT_COMPILER_DEBUG_PATH_SANITIZER,
                compiler,
                CxxToolFlags.of()),
            CxxToolFlags.of(),
            new FakeSourcePath("foo.h"),
            CxxSource.Type.C,
            CxxPlatformUtils.DEFAULT_COMPILER_DEBUG_PATH_SANITIZER);
    resolver.addToIndex(precompiledHeader);
    BuildContext buildContext = FakeBuildContext.withSourcePathResolver(sourcePathResolver);
    ImmutableList<Step> postBuildSteps =
        precompiledHeader.getBuildSteps(buildContext, new FakeBuildableContext());
    CxxPreprocessAndCompileStep step =
        Iterables.getOnlyElement(
            Iterables.filter(postBuildSteps, CxxPreprocessAndCompileStep.class));
    assertThat(
        "step that generates pch should have correct flags",
        step.getCommand(),
        hasItem(CxxSource.Type.C.getPrecompiledHeaderLanguage().get()));
  }
}