// 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 com.android.tools.r8.D8CommandParser.OrderedClassFileResourceProvider;
import com.android.tools.r8.origin.Origin;
import com.android.tools.r8.utils.AndroidApiLevel;
import com.android.tools.r8.utils.FlagFile;
import com.android.tools.r8.utils.StringDiagnostic;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Arrays;
import java.util.Set;

public class L8CommandParser extends BaseCompilerCommandParser<L8Command, L8Command.Builder> {

  private static final Set<String> OPTIONS_WITH_PARAMETER = ImmutableSet.of(
      "--output", "--lib", MIN_API_FLAG, "--desugared-lib", THREAD_COUNT_FLAG, "--pg-conf");

  public static void main(String[] args) throws CompilationFailedException {
    L8Command command = parse(args, Origin.root()).build();
    if (command.isPrintHelp()) {
      System.out.println(USAGE_MESSAGE);
      System.exit(1);
    }
    L8.run(command);
  }

  static final String USAGE_MESSAGE =
      String.join(
          "\n",
          Iterables.concat(
              Arrays.asList(
                  "Usage: l8 [options] <input-files>",
                  " where <input-files> are any combination of dex, class, zip, jar, or apk files",
                  " and options are:",
                  "  --debug                 # Compile with debugging information (default).",
                  "  --release               # Compile without debugging information.",
                  "  --output <file>         # Output result in <outfile>.",
                  "                          # <file> must be an existing directory or a zip file.",
                  "  --lib <file|jdk-home>   # Add <file|jdk-home> as a library resource.",
                  "  "
                      + MIN_API_FLAG
                      + " <number>      "
                      + "# Minimum Android API level compatibility, default: "
                      + AndroidApiLevel.getDefault().getLevel()
                      + ".",
                  "  --pg-conf <file>        # Proguard configuration <file>.",
                  "  --desugared-lib <file>  # Specify desugared library configuration.",
                  "                          # <file> is a desugared library configuration"
                      + " (json)."),
              ASSERTIONS_USAGE_MESSAGE,
              Arrays.asList(
                  "  --version               # Print the version of l8.",
                  "  --help                  # Print this message.")));

  /**
   * Parse the D8 command-line.
   *
   * <p>Parsing will set the supplied options or their default value if they have any.
   *
   * @param args Command-line arguments array.
   * @param origin Origin description of the command-line arguments.
   * @return D8 command builder with state set up according to parsed command line.
   */
  public static L8Command.Builder parse(String[] args, Origin origin) {
    return new L8CommandParser().parse(args, origin, L8Command.builder());
  }

  /**
   * Parse the D8 command-line.
   *
   * <p>Parsing will set the supplied options or their default value if they have any.
   *
   * @param args Command-line arguments array.
   * @param origin Origin description of the command-line arguments.
   * @param handler Custom defined diagnostics handler.
   * @return D8 command builder with state set up according to parsed command line.
   */
  public static L8Command.Builder parse(String[] args, Origin origin, DiagnosticsHandler handler) {
    return new L8CommandParser().parse(args, origin, L8Command.builder(handler));
  }

  private L8Command.Builder parse(String[] args, Origin origin, L8Command.Builder builder) {
    CompilationMode compilationMode = null;
    Path outputPath = null;
    OutputMode outputMode = OutputMode.DexIndexed;
    boolean hasDefinedApiLevel = false;
    OrderedClassFileResourceProvider.Builder classpathBuilder =
        OrderedClassFileResourceProvider.builder();
    String[] expandedArgs = FlagFile.expandFlagFiles(args, builder::error);
    for (int i = 0; i < expandedArgs.length; i++) {
      String arg = expandedArgs[i].trim();
      String nextArg = null;
      if (OPTIONS_WITH_PARAMETER.contains(arg)) {
        if (++i < expandedArgs.length) {
          nextArg = expandedArgs[i];
        } else {
          builder.error(
              new StringDiagnostic("Missing parameter for " + expandedArgs[i - 1] + ".", origin));
          break;
        }
      }
      if (arg.length() == 0) {
        continue;
      } else if (arg.equals("--help")) {
        builder.setPrintHelp(true);
      } else if (arg.equals("--version")) {
        builder.setPrintVersion(true);
      } else if (arg.equals("--debug")) {
        if (compilationMode == CompilationMode.RELEASE) {
          builder.error(
              new StringDiagnostic("Cannot compile in both --debug and --release mode.", origin));
          continue;
        }
        compilationMode = CompilationMode.DEBUG;
      } else if (arg.equals("--release")) {
        if (compilationMode == CompilationMode.DEBUG) {
          builder.error(
              new StringDiagnostic("Cannot compile in both --debug and --release mode.", origin));
          continue;
        }
        compilationMode = CompilationMode.RELEASE;
      } else if (arg.equals("--output")) {
        if (outputPath != null) {
          builder.error(
              new StringDiagnostic(
                  "Cannot output both to '" + outputPath.toString() + "' and '" + nextArg + "'",
                  origin));
          continue;
        }
        outputPath = Paths.get(nextArg);
      } else if (arg.equals(MIN_API_FLAG)) {
        if (hasDefinedApiLevel) {
          builder.error(
              new StringDiagnostic("Cannot set multiple " + MIN_API_FLAG + " options", origin));
        } else {
          parsePositiveIntArgument(
              builder::error, MIN_API_FLAG, nextArg, origin, builder::setMinApiLevel);
          hasDefinedApiLevel = true;
        }
      } else if (arg.equals("--lib")) {
        addLibraryArgument(builder, origin, nextArg);
      } else if (arg.equals("--pg-conf")) {
        builder.addProguardConfigurationFiles(Paths.get(nextArg));
      } else if (arg.equals("--desugared-lib")) {
        builder.addDesugaredLibraryConfiguration(StringResource.fromFile(Paths.get(nextArg)));
      } else if (arg.equals("--classfile")) {
        outputMode = OutputMode.ClassFile;
      } else if (arg.equals(THREAD_COUNT_FLAG)) {
        parsePositiveIntArgument(
            builder::error, THREAD_COUNT_FLAG, nextArg, origin, builder::setThreadCount);
      } else if (arg.startsWith("--")) {
        if (!tryParseAssertionArgument(builder, arg, origin)) {
          builder.error(new StringDiagnostic("Unknown option: " + arg, origin));
          continue;
        }
      } else {
        builder.addProgramFiles(Paths.get(arg));
      }
    }
    if (!classpathBuilder.isEmpty()) {
      builder.addClasspathResourceProvider(classpathBuilder.build());
    }
    if (compilationMode != null) {
      builder.setMode(compilationMode);
    }
    if (outputPath == null) {
      outputPath = Paths.get(".");
    }
    return builder.setOutput(outputPath, outputMode);
  }
}