/*
 * Copyright (C) 2020 The Dagger Authors.
 *
 * 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 dagger.testing.compile;

import static com.google.common.base.Strings.isNullOrEmpty;
import static com.google.common.collect.MoreCollectors.onlyElement;
import static com.google.common.collect.Streams.stream;
import static com.google.testing.compile.Compiler.javac;

import androidx.room.compiler.processing.XProcessingEnvConfig;
import androidx.room.compiler.processing.util.CompilationResultSubject;
import androidx.room.compiler.processing.util.ProcessorTestExtKt;
import androidx.room.compiler.processing.util.Source;
import androidx.room.compiler.processing.util.compiler.TestCompilationArguments;
import androidx.room.compiler.processing.util.compiler.TestCompilationResult;
import androidx.room.compiler.processing.util.compiler.TestKotlinCompilerKt;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.io.Files;
import com.google.testing.compile.Compiler;
import dagger.internal.codegen.ComponentProcessor;
import dagger.internal.codegen.KspComponentProcessor;
import java.io.File;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.function.Consumer;
import org.junit.rules.TemporaryFolder;

/** A helper class for working with java compiler tests. */
public final class CompilerTests {
  // TODO(bcorso): Share this with java/dagger/internal/codegen/DelegateComponentProcessor.java
  private static final XProcessingEnvConfig PROCESSING_ENV_CONFIG =
      new XProcessingEnvConfig.Builder().disableAnnotatedElementValidation(true).build();

  // TODO(bcorso): Share this with javatests/dagger/internal/codegen/Compilers.java
  private static final ImmutableMap<String, String> DEFAULT_PROCESSOR_OPTIONS =
      ImmutableMap.of(
          "dagger.experimentalDaggerErrorMessages", "enabled");

  /** Returns the {@plainlink File jar file} containing the compiler deps. */
  public static File compilerDepsJar() {
    try {
      return stream(Files.fileTraverser().breadthFirst(getRunfilesDir()))
          .filter(file -> file.getName().endsWith("_compiler_deps_deploy.jar"))
          .collect(onlyElement());
    } catch (NoSuchElementException e) {
      throw new IllegalStateException(
          "No compiler deps jar found. Are you using the Dagger compiler_test macro?", e);
    }
  }

  /** Returns a {@link Compiler} with the compiler deps jar added to the class path. */
  public static Compiler compiler() {
    return javac().withClasspath(ImmutableList.of(compilerDepsJar()));
  }

  public static void compileWithKapt(
      List<Source> sources,
      TemporaryFolder tempFolder,
      Consumer<TestCompilationResult> onCompilationResult) {
    compileWithKapt(sources, ImmutableMap.of(), tempFolder, onCompilationResult);
  }

  public static void compileWithKapt(
      List<Source> sources,
      Map<String, String> processorOptions,
      TemporaryFolder tempFolder,
      Consumer<TestCompilationResult> onCompilationResult) {
    TestCompilationResult result = TestKotlinCompilerKt.compile(
        tempFolder.getRoot(),
        new TestCompilationArguments(
            sources,
            /*classpath=*/ ImmutableList.of(compilerDepsJar()),
            /*inheritClasspath=*/ false,
            /*javacArguments=*/ ImmutableList.of(),
            /*kotlincArguments=*/ ImmutableList.of(),
            /*kaptProcessors=*/ ImmutableList.of(new ComponentProcessor()),
            /*symbolProcessorProviders=*/ ImmutableList.of(),
            /*processorOptions=*/ processorOptions));
    onCompilationResult.accept(result);
  }

  // TODO(bcorso): For Java users we may want to have a builder, similar to
  // "com.google.testing.compile.Compiler", so that users can easily add custom options or
  // processors along with their sources.
  public static void compile(
      ImmutableList<Source> sources, Consumer<CompilationResultSubject> onCompilationResult) {
    ProcessorTestExtKt.runProcessorTest(
        sources,
        /*classpath=*/ ImmutableList.of(compilerDepsJar()),
        /*options=*/ DEFAULT_PROCESSOR_OPTIONS,
        /*javacArguments=*/ ImmutableList.of(),
        /*kotlincArguments=*/ ImmutableList.of(),
        /*config=*/ PROCESSING_ENV_CONFIG,
        /*javacProcessors=*/ ImmutableList.of(new ComponentProcessor()),
        /*symbolProcessorProviders=*/ ImmutableList.of(new KspComponentProcessor.Provider()),
        // TODO(bcorso): Typically, we would return a CompilationResult here and users would wrap
        // that in an "assertThat" method to get the CompilationResultSubject.
        result -> {
          onCompilationResult.accept(result);
          return null;
        });
  }

  private static File getRunfilesDir() {
    return getRunfilesPath().toFile();
  }

  private static Path getRunfilesPath() {
    Path propPath = getRunfilesPath(System.getProperties());
    if (propPath != null) {
      return propPath;
    }

    Path envPath = getRunfilesPath(System.getenv());
    if (envPath != null) {
      return envPath;
    }

    Path cwd = Paths.get("").toAbsolutePath();
    return cwd.getParent();
  }

  private static Path getRunfilesPath(Map<?, ?> map) {
    String runfilesPath = (String) map.get("TEST_SRCDIR");
    return isNullOrEmpty(runfilesPath) ? null : Paths.get(runfilesPath);
  }

  private CompilerTests() {}
}