// 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;

import static org.hamcrest.CoreMatchers.startsWith;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

import com.android.tools.r8.naming.ClassNameMapper;
import com.android.tools.r8.utils.ZipUtils;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.NoSuchFileException;
import java.nio.file.Path;
import java.util.Enumeration;
import java.util.function.Predicate;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
import org.junit.Test;

public class SanityCheck extends TestBase {

  private static final String SRV_PREFIX = "META-INF/services/";
  private static final String METADATA_EXTENSION =
      "com.android.tools.r8.jetbrains.kotlinx.metadata.impl.extensions.MetadataExtensions";
  private static final String EXT_IN_SRV = SRV_PREFIX + METADATA_EXTENSION;

    private void checkJarContent(
      Path jar, boolean allowDirectories, Predicate<String> entryTester)
      throws Exception {
    ZipFile zipFile;
    try {
      zipFile = new ZipFile(jar.toFile(), StandardCharsets.UTF_8);
    } catch (IOException e) {
      if (!Files.exists(jar)) {
        throw new NoSuchFileException(jar.toString());
      } else {
        throw e;
      }
    }
    boolean licenseSeen = false;
    final Enumeration<? extends ZipEntry> entries = zipFile.entries();
    while (entries.hasMoreElements()) {
      ZipEntry entry = entries.nextElement();
      String name = entry.getName();
      if (ZipUtils.isClassFile(name) || name.endsWith(".kotlin_builtins")) {
        assertThat(name, startsWith("com/android/tools/r8/"));
      } else if (name.equals("META-INF/MANIFEST.MF")) {
        // Allow.
      } else if (name.equals("LICENSE")) {
        licenseSeen = true;
      } else if (entryTester.test(name)) {
        // Allow.
      } else if (name.endsWith("/")) {
        assertTrue("Unexpected directory entry in" + jar, allowDirectories);
      } else {
        fail("Unexpected entry '" + name + "' in " + jar);
      }
    }
    assertTrue("No LICENSE entry found in " + jar, licenseSeen);
  }

  private void checkLibJarContent(Path jar, Path map) throws Exception {
    if (!Files.exists(jar)) {
      return;
    }
    assertTrue(Files.exists(map));
    ClassNameMapper mapping = ClassNameMapper.mapperFromFile(map);
    checkJarContent(jar, false, name -> metadataExtensionTester(name, mapping));
  }

  private void checkJarContent(Path jar) throws Exception {
    if (!Files.exists(jar)) {
      return;
    }
    checkJarContent(jar, true, name -> metadataExtensionTester(name, null));
  }

  private boolean metadataExtensionTester(String name, ClassNameMapper mapping) {
    if (name.equals(EXT_IN_SRV)) {
      assertNull(mapping);
      return true;
    }
    if (mapping != null && name.startsWith(SRV_PREFIX)) {
      String obfuscatedName = name.substring(SRV_PREFIX.length());
      String originalName =
          mapping.getObfuscatedToOriginalMapping().original
              .getOrDefault(obfuscatedName, obfuscatedName);
      if (originalName.equals(METADATA_EXTENSION)) {
        return true;
      }
    }
    return false;
  }

  @Test
  public void testLibJarsContent() throws Exception {
    checkLibJarContent(ToolHelper.R8LIB_JAR, ToolHelper.R8LIB_MAP);
    checkLibJarContent(ToolHelper.R8LIB_EXCLUDE_DEPS_JAR, ToolHelper.R8LIB_EXCLUDE_DEPS_MAP);
  }

  @Test
  public void testJarsContent() throws Exception {
    checkJarContent(ToolHelper.D8_JAR);
    checkJarContent(ToolHelper.R8_JAR);
  }
}