// Copyright 2015 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.android;

import com.android.builder.core.VariantType;
import com.android.utils.StdLogger;
import com.google.common.base.Preconditions;
import com.google.common.base.Stopwatch;
import com.google.devtools.build.android.AndroidResourceProcessor.AaptConfigOptions;
import com.google.devtools.build.android.AndroidResourceProcessor.FlagAaptOptions;
import com.google.devtools.build.android.Converters.ExistingPathConverter;
import com.google.devtools.build.android.Converters.PathConverter;
import com.google.devtools.common.options.Option;
import com.google.devtools.common.options.OptionDocumentationCategory;
import com.google.devtools.common.options.OptionEffectTag;
import com.google.devtools.common.options.OptionsBase;
import com.google.devtools.common.options.OptionsParser;
import com.google.devtools.common.options.ShellQuotedParamsFilePreProcessor;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.file.FileSystems;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.concurrent.TimeUnit;
import java.util.logging.Logger;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;

/**
 * Validates merged resources for an android_library via AAPT. Takes as input, the merged resources
 * from {@link AndroidResourceMergingAction}.
 */
public class AndroidResourceValidatorAction {

  private static final StdLogger stdLogger = new StdLogger(StdLogger.Level.WARNING);

  private static final Logger logger =
      Logger.getLogger(AndroidResourceValidatorAction.class.getName());

  /** Flag specifications for this action. */
  public static final class Options extends OptionsBase {

    @Option(
        name = "mergedResources",
        defaultValue = "null",
        converter = ExistingPathConverter.class,
        category = "input",
        documentationCategory = OptionDocumentationCategory.UNCATEGORIZED,
        effectTags = {OptionEffectTag.UNKNOWN},
        help = "Path to the read merged resources archive.")
    public Path mergedResources;

    @Option(
        name = "manifest",
        defaultValue = "null",
        converter = ExistingPathConverter.class,
        category = "input",
        documentationCategory = OptionDocumentationCategory.UNCATEGORIZED,
        effectTags = {OptionEffectTag.UNKNOWN},
        help = "Path for the AndroidManifest.xml.")
    public Path manifest;

    @Option(
        name = "packageForR",
        defaultValue = "null",
        category = "config",
        documentationCategory = OptionDocumentationCategory.UNCATEGORIZED,
        effectTags = {OptionEffectTag.UNKNOWN},
        help = "Custom java package to generate the R symbols files.")
    public String packageForR;

    @Option(
        name = "srcJarOutput",
        defaultValue = "null",
        converter = PathConverter.class,
        category = "output",
        documentationCategory = OptionDocumentationCategory.UNCATEGORIZED,
        effectTags = {OptionEffectTag.UNKNOWN},
        help = "Path for the generated java source jar.")
    public Path srcJarOutput;

    @Option(
        name = "rOutput",
        defaultValue = "null",
        converter = PathConverter.class,
        category = "output",
        documentationCategory = OptionDocumentationCategory.UNCATEGORIZED,
        effectTags = {OptionEffectTag.UNKNOWN},
        help = "Path to where the R.txt should be written.")
    public Path rOutput;

    @Option(
        name = "packagePath",
        defaultValue = "null",
        converter = PathConverter.class,
        category = "output",
        documentationCategory = OptionDocumentationCategory.UNCATEGORIZED,
        effectTags = {OptionEffectTag.UNKNOWN},
        help = "Path to the write the archive.")
    // TODO(b/30307842): Remove this once it is no longer needed for resources migration.
    public Path packagePath;
  }

  public static void main(String[] args) throws Exception {
    final Stopwatch timer = Stopwatch.createStarted();
    OptionsParser optionsParser =
        OptionsParser.builder()
            .optionsClasses(Options.class, AaptConfigOptions.class)
            .argsPreProcessor(new ShellQuotedParamsFilePreProcessor(FileSystems.getDefault()))
            .build();
    optionsParser.parseAndExitUponError(args);
    AaptConfigOptions aaptConfigOptions = optionsParser.getOptions(AaptConfigOptions.class);
    Options options = optionsParser.getOptions(Options.class);

    final AndroidResourceProcessor resourceProcessor = new AndroidResourceProcessor(stdLogger);
    VariantType packageType = VariantType.LIBRARY;

    Preconditions.checkNotNull(options.rOutput);
    Preconditions.checkNotNull(options.srcJarOutput);

    try (ScopedTemporaryDirectory scopedTmp =
        new ScopedTemporaryDirectory("resource_validator_tmp")) {
      Path tmp = scopedTmp.getPath();
      Path expandedOut = tmp.resolve("tmp-expanded");
      Path resources = expandedOut.resolve("res");
      Path assets = expandedOut.resolve("assets");
      Path generatedSources = tmp.resolve("generated_resources");
      Path dummyManifestDirectory = tmp.resolve("manifest-aapt-dummy");

      unpackZip(options.mergedResources, expandedOut);
      logger.fine(String.format("unpacked zip at %sms", timer.elapsed(TimeUnit.MILLISECONDS)));

      // We need to make the manifest aapt safe (w.r.t., placeholders). For now, just stub it out.

      resourceProcessor.runAapt(
          tmp,
          aaptConfigOptions.aapt,
          aaptConfigOptions.androidJar,
          aaptConfigOptions.buildToolsVersion,
          packageType,
          aaptConfigOptions.debug,
          options.packageForR,
          new FlagAaptOptions(aaptConfigOptions),
          aaptConfigOptions.resourceConfigs,
          AndroidManifest.parseFrom(options.manifest)
              .writeDummyManifestForAapt(dummyManifestDirectory, options.packageForR),
          resources,
          assets,
          generatedSources,
          options.packagePath,
          /* proguardOut= */ null,
          /* mainDexProguardOut= */ null,
          /* publicResourcesOut= */ null);
      logger.fine(String.format("aapt finished at %sms", timer.elapsed(TimeUnit.MILLISECONDS)));

      AndroidResourceOutputs.copyRToOutput(
          generatedSources, options.rOutput, VariantType.LIBRARY == packageType);

      AndroidResourceOutputs.createSrcJar(
          generatedSources, options.srcJarOutput, VariantType.LIBRARY == packageType);
    } catch (Exception e) {
      logger.log(java.util.logging.Level.SEVERE, "Unexpected", e);
      throw e;
    } finally {
      resourceProcessor.shutdown();
    }
    logger.fine(String.format("Resources merged in %sms", timer.elapsed(TimeUnit.MILLISECONDS)));
  }

  private static void unpackZip(Path mergedResources, Path expandedOut) throws IOException {
    byte[] buffer = new byte[4096];
    try (ZipInputStream zis =
        new ZipInputStream(new BufferedInputStream(Files.newInputStream(mergedResources)))) {
      ZipEntry z = zis.getNextEntry();
      while (z != null) {
        String entryName = z.getName();
        // Skip directory entries
        if (entryName.endsWith("/")) {
          z = zis.getNextEntry();
          continue;
        }
        Path outputPath = expandedOut.resolve(entryName);
        Files.createDirectories(outputPath.getParent());
        try (OutputStream out = new BufferedOutputStream(Files.newOutputStream(outputPath))) {
          int count = zis.read(buffer);
          while (count != -1) {
            out.write(buffer, 0, count);
            count = zis.read(buffer);
          }
        }
        z = zis.getNextEntry();
      }
    }
  }
}