// Copyright (c) 2019, the R8 project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

package com.android.tools.r8.desugar.desugaredlibrary;

import static com.android.tools.r8.utils.InternalOptions.ASM_VERSION;
import static junit.framework.TestCase.assertEquals;
import static junit.framework.TestCase.assertTrue;

import com.android.tools.r8.CompilationFailedException;
import com.android.tools.r8.CompilationMode;
import com.android.tools.r8.DiagnosticsHandler;
import com.android.tools.r8.L8Command;
import com.android.tools.r8.OutputMode;
import com.android.tools.r8.StringConsumer;
import com.android.tools.r8.StringResource;
import com.android.tools.r8.TestBase;
import com.android.tools.r8.TestDiagnosticMessagesImpl;
import com.android.tools.r8.TestParameters;
import com.android.tools.r8.TestParametersCollection;
import com.android.tools.r8.ToolHelper;
import com.android.tools.r8.ToolHelper.DexVm.Version;
import com.android.tools.r8.errors.Unreachable;
import com.android.tools.r8.ir.desugar.DesugaredLibraryConfiguration;
import com.android.tools.r8.ir.desugar.DesugaredLibraryConfigurationParser;
import com.android.tools.r8.ir.desugar.NestBasedAccessDesugaring;
import com.android.tools.r8.origin.Origin;
import com.android.tools.r8.tracereferences.TraceReferences;
import com.android.tools.r8.utils.AndroidApiLevel;
import com.android.tools.r8.utils.FileUtils;
import com.android.tools.r8.utils.InternalOptions;
import com.android.tools.r8.utils.codeinspector.CodeInspector;
import com.google.common.base.Charsets;
import com.google.common.collect.ImmutableList;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.function.Consumer;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.MethodVisitor;

public class DesugaredLibraryTestBase extends TestBase {

  // For conversions tests, we need DexRuntimes where classes to convert are present (DexRuntimes
  // above N and O depending if Stream or Time APIs are used), but we need to compile the program
  // with a minAPI below to force the use of conversions.
  protected static TestParametersCollection getConversionParametersUpToExcluding(
      AndroidApiLevel apiLevel) {
    if (apiLevel == AndroidApiLevel.N) {
      return getTestParameters()
          .withDexRuntimesStartingFromIncluding(Version.V7_0_0)
          .withApiLevelsEndingAtExcluding(AndroidApiLevel.N)
          .build();
    }
    if (apiLevel == AndroidApiLevel.O) {
      return getTestParameters()
          .withDexRuntimesStartingFromIncluding(Version.V8_1_0)
          .withApiLevelsEndingAtExcluding(AndroidApiLevel.O)
          .build();
    }
    throw new Error("Unsupported conversion parameters");
  }

  protected boolean requiresEmulatedInterfaceCoreLibDesugaring(TestParameters parameters) {
    return parameters.getApiLevel().isLessThan(apiLevelWithDefaultInterfaceMethodsSupport());
  }

  protected boolean requiresAnyCoreLibDesugaring(TestParameters parameters) {
    return parameters.getApiLevel().getLevel() < AndroidApiLevel.O.getLevel();
  }

  protected Path buildDesugaredLibrary(AndroidApiLevel apiLevel) {
    return buildDesugaredLibrary(apiLevel, "", false);
  }

  protected Path buildDesugaredLibrary(
      AndroidApiLevel apiLevel, Consumer<InternalOptions> optionsModifier) {
    return buildDesugaredLibrary(apiLevel, "", false, ImmutableList.of(), optionsModifier);
  }

  protected Path buildDesugaredLibrary(AndroidApiLevel apiLevel, String keepRules) {
    return buildDesugaredLibrary(apiLevel, keepRules, true);
  }

  protected Path buildDesugaredLibrary(AndroidApiLevel apiLevel, String keepRules, boolean shrink) {
    return buildDesugaredLibrary(apiLevel, keepRules, shrink, ImmutableList.of(), options -> {});
  }

  protected Path buildDesugaredLibrary(
      AndroidApiLevel apiLevel,
      String keepRules,
      boolean shrink,
      List<Path> additionalProgramFiles) {
    return buildDesugaredLibrary(
        apiLevel, keepRules, shrink, additionalProgramFiles, options -> {});
  }

  protected Path buildDesugaredLibrary(
      AndroidApiLevel apiLevel,
      String keepRules,
      boolean shrink,
      List<Path> additionalProgramFiles,
      Consumer<InternalOptions> optionsModifier) {
    // We wrap exceptions in a RuntimeException to call this from a lambda.
    try {
      // If we compile extended library here, it means we use TestNG.
      // TestNG requires annotations, hence we disable AnnotationRemoval.
      // This implies that extra warning are generated if this is set.
      boolean extraFiles = !additionalProgramFiles.isEmpty();
      ArrayList<Path> extraPaths = new ArrayList<>(additionalProgramFiles);
      TestDiagnosticMessagesImpl diagnosticsHandler = new TestDiagnosticMessagesImpl();
      Path desugaredLib = temp.newFolder().toPath().resolve("desugar_jdk_libs_dex.zip");
      L8Command.Builder l8Builder =
          L8Command.builder(diagnosticsHandler)
              .addLibraryFiles(ToolHelper.getAndroidJar(AndroidApiLevel.P))
              .addProgramFiles(ToolHelper.getDesugarJDKLibs())
              .addProgramFiles(ToolHelper.DESUGAR_LIB_CONVERSIONS)
              .setMode(shrink ? CompilationMode.RELEASE : CompilationMode.DEBUG)
              .addProgramFiles(extraPaths)
              .addDesugaredLibraryConfiguration(
                  StringResource.fromFile(ToolHelper.DESUGAR_LIB_JSON_FOR_TESTING))
              .setMinApiLevel(apiLevel.getLevel())
              .setOutput(desugaredLib, OutputMode.DexIndexed);
      if (shrink) {
        l8Builder.addProguardConfiguration(
            Arrays.asList(keepRules.split(System.lineSeparator())), Origin.unknown());
      }
      ToolHelper.runL8(
          l8Builder.build(),
          options -> {
            if (extraFiles) {
              options.testing.disableL8AnnotationRemoval = true;
            }
            optionsModifier.accept(options);
          });
      if (!extraFiles) {
        assertTrue(
            diagnosticsHandler.getInfos().stream()
                .noneMatch(
                    string ->
                        string
                            .getDiagnosticMessage()
                            .startsWith(
                                "Invalid parameter counts in MethodParameter attributes.")));
      }
      // TODO(b/176900254): The nest check should not be necessary.
      new CodeInspector(desugaredLib)
          .forAllClasses(
              clazz ->
                  assertTrue(
                      clazz.getFinalName().startsWith("j$.")
                          || clazz
                              .getFinalName()
                              .startsWith(NestBasedAccessDesugaring.NEST_CONSTRUCTOR_NAME)));
      return desugaredLib;
    } catch (Exception e) {
      // Don't wrap assumption violation so junit can catch it.
      if (e instanceof RuntimeException) {
        throw ((RuntimeException) e);
      }
      throw new RuntimeException(e);
    }
  }

  protected void assertLines2By2Correct(String stdOut) {
    String[] lines = stdOut.split("\n");
    assert lines.length % 2 == 0;
    for (int i = 0; i < lines.length; i += 2) {
      assertEquals(
          "Different lines: " + lines[i] + " || " + lines[i + 1] + "\n" + stdOut,
          lines[i],
          lines[i + 1]);
    }
  }

  protected static Path[] getAllFilesWithSuffixInDirectory(Path directory, String suffix)
      throws IOException {
    return Files.walk(directory)
        .filter(path -> path.toString().endsWith(suffix))
        .toArray(Path[]::new);
  }

  protected KeepRuleConsumer createKeepRuleConsumer(TestParameters parameters) {
    if (requiresAnyCoreLibDesugaring(parameters)) {
      return new PresentKeepRuleConsumer();
    }
    return new AbsentKeepRuleConsumer();
  }

  public Path getDesugaredLibraryInCF(
      TestParameters parameters, Consumer<InternalOptions> configurationForLibraryCompilation)
      throws IOException, CompilationFailedException {
    Path desugaredLib = temp.newFolder().toPath().resolve("desugar_jdk_libs.jar");
    L8Command.Builder l8Builder =
        L8Command.builder()
            .addLibraryFiles(ToolHelper.getAndroidJar(AndroidApiLevel.P))
            .addProgramFiles(ToolHelper.getDesugarJDKLibs())
            .addProgramFiles(ToolHelper.DESUGAR_LIB_CONVERSIONS)
            .setMode(CompilationMode.DEBUG)
            .addDesugaredLibraryConfiguration(
                StringResource.fromFile(ToolHelper.DESUGAR_LIB_JSON_FOR_TESTING))
            .setMinApiLevel(parameters.getApiLevel().getLevel())
            .setOutput(desugaredLib, OutputMode.ClassFile);

    ToolHelper.runL8(l8Builder.build(), configurationForLibraryCompilation);
    return desugaredLib;
  }

  protected DesugaredLibraryConfiguration configurationWithSupportAllCallbacksFromLibrary(
      InternalOptions options,
      boolean libraryCompilation,
      TestParameters parameters,
      boolean supportAllCallbacksFromLibrary) {
    return new DesugaredLibraryConfigurationParser(
            options.dexItemFactory(),
            options.reporter,
            libraryCompilation,
            parameters.getApiLevel().getLevel())
        .parse(
            StringResource.fromFile(ToolHelper.DESUGAR_LIB_JSON_FOR_TESTING),
            builder -> builder.setSupportAllCallbacksFromLibrary(supportAllCallbacksFromLibrary));
  }

  private Map<AndroidApiLevel, Path> desugaredLibraryClassFileCache = new HashMap<>();

  // Build the desugared library in class file format.
  public Path buildDesugaredLibraryClassFile(AndroidApiLevel apiLevel) throws Exception {
    Path desugaredLib = desugaredLibraryClassFileCache.get(apiLevel);
    if (desugaredLib != null) {
      return desugaredLib;
    }
    desugaredLib = temp.newFolder().toPath().resolve("desugar_jdk_libs.jar");
    L8Command.Builder l8Builder =
        L8Command.builder()
            .addLibraryFiles(ToolHelper.getAndroidJar(AndroidApiLevel.P))
            .addProgramFiles(ToolHelper.getDesugarJDKLibs())
            .addProgramFiles(ToolHelper.DESUGAR_LIB_CONVERSIONS)
            .setMode(CompilationMode.DEBUG)
            .addDesugaredLibraryConfiguration(
                StringResource.fromFile(ToolHelper.DESUGAR_LIB_JSON_FOR_TESTING))
            .setMinApiLevel(apiLevel.getLevel())
            .setOutput(desugaredLib, OutputMode.ClassFile);
    ToolHelper.runL8(l8Builder.build());
    desugaredLibraryClassFileCache.put(apiLevel, desugaredLib);
    return desugaredLib;
  }

  public String collectKeepRulesWithTraceReferences(
      Path desugaredProgramClassFile, Path desugaredLibraryClassFile) throws Exception {
    Path generatedKeepRules = temp.newFile().toPath();
    TraceReferences.run(
        "--keep-rules",
        "--lib",
        ToolHelper.getAndroidJar(AndroidApiLevel.P).toString(),
        "--target",
        desugaredLibraryClassFile.toString(),
        "--source",
        desugaredProgramClassFile.toString(),
        "--output",
        generatedKeepRules.toString(),
        "--map-diagnostics",
        "error",
        "info");
    return FileUtils.readTextFile(generatedKeepRules, Charsets.UTF_8);
  }

  protected static ClassFileInfo extractClassFileInfo(byte[] classFileBytes) {
    class ClassFileInfoExtractor extends ClassVisitor {
      private String classBinaryName;
      private List<String> interfaces = new ArrayList<>();
      private final List<String> methodNames = new ArrayList<>();

      private ClassFileInfoExtractor() {
        super(ASM_VERSION);
      }

      @Override
      public void visit(
          int version,
          int access,
          String name,
          String signature,
          String superName,
          String[] interfaces) {
        classBinaryName = name;
        this.interfaces.addAll(Arrays.asList(interfaces));
        super.visit(version, access, name, signature, superName, interfaces);
      }

      @Override
      public MethodVisitor visitMethod(
          int access, String name, String desc, String signature, String[] exceptions) {
        methodNames.add(name);
        return super.visitMethod(access, name, desc, signature, exceptions);
      }

      ClassFileInfo getClassFileInfo() {
        return new ClassFileInfo(classBinaryName, interfaces, methodNames);
      }
    }

    ClassReader reader = new ClassReader(classFileBytes);
    ClassFileInfoExtractor extractor = new ClassFileInfoExtractor();
    reader.accept(
        extractor, ClassReader.SKIP_CODE | ClassReader.SKIP_DEBUG | ClassReader.SKIP_FRAMES);
    return extractor.getClassFileInfo();
  }

  public interface KeepRuleConsumer extends StringConsumer {

    String get();
  }

  public static class AbsentKeepRuleConsumer implements KeepRuleConsumer {

    public String get() {
      return null;
    }

    @Override
    public void accept(String string, DiagnosticsHandler handler) {
      throw new Unreachable("No desugaring on high API levels");
    }

    @Override
    public void finished(DiagnosticsHandler handler) {
      throw new Unreachable("No desugaring on high API levels");
    }
  }

  public static class PresentKeepRuleConsumer implements KeepRuleConsumer {

    StringBuilder stringBuilder = new StringBuilder();
    String result = null;

    @Override
    public void accept(String string, DiagnosticsHandler handler) {
      assert stringBuilder != null;
      assert result == null;
      stringBuilder.append(string);
    }

    @Override
    public void finished(DiagnosticsHandler handler) {
      assert stringBuilder != null;
      assert result == null;
      result = stringBuilder.toString();
      stringBuilder = null;
    }

    public String get() {
      // TODO(clement): remove that branch once StringConsumer has finished again.
      if (stringBuilder != null) {
        finished(null);
      }

      assert stringBuilder == null;
      assert result != null;
      return result;
    }
  }

  protected static class ClassFileInfo {
    private final String classBinaryName;
    private List<String> interfaces;
    private final List<String> methodNames;

    ClassFileInfo(String classBinaryNamename, List<String> interfaces, List<String> methodNames) {
      this.classBinaryName = classBinaryNamename;
      this.interfaces = interfaces;
      this.methodNames = methodNames;
    }

    public String getClassBinaryName() {
      return classBinaryName;
    }

    public List<String> getInterfaces() {
      return interfaces;
    }

    public List<String> getMethodNames() {
      return methodNames;
    }
  }
}