/*
 * Copyright 2000-2014 JetBrains s.r.o.
 *
 * 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 jetbrains.buildServer.agent.rakerunner.utils;

import java.io.File;
import java.util.Map;

import jetbrains.buildServer.ExecResult;
import jetbrains.buildServer.RunBuildException;
import jetbrains.buildServer.agent.BuildRunnerContext;
import jetbrains.buildServer.agent.rakerunner.RakeTasksBuildService;
import jetbrains.buildServer.agent.rakerunner.SharedParams;
import jetbrains.buildServer.agent.ruby.RubySdk;
import jetbrains.buildServer.util.StringUtil;
import org.jetbrains.annotations.NonNls;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import static com.intellij.openapi.util.io.FileUtil.getTempDirectory;

/**
 * @author Roman.Chernyatchik
 */
public class InternalRubySdkUtil {
  public static final String RUBY_VERSION_SCRIPT = "print RUBY_VERSION";
  public static final String RUBY_PLATFORM_SCRIPT = "print RUBY_PLATFORM";
  @NonNls
  public static final String GET_LOAD_PATH_SCRIPT = "puts $LOAD_PATH";
  public static final String RUBY19_DISABLE_GEMS_OPTION = "--disable-gems";

  @NotNull
  static RubySdk createSdk(@NotNull final Map<String, String> runParameters,
                           @NotNull final BuildRunnerContext context)
    throws RakeTasksBuildService.MyBuildFailureException, RunBuildException {

    // Check if path to ruby interpreter was explicitly set
    // and calculate corresponding interpreter path

    final RubySdk sdk = SharedParams.fromRunParameters(runParameters).createSdk(context);

    // Final check that interpreter file exists
    try {
      final File executable = sdk.getRubyExecutable();
      if (!executable.exists()) {
        throwInterpreterDoesntExistError(executable.getAbsolutePath());
      }
    } catch (SecurityException e) {
      //unknown error
      throw new RunBuildException(e.getMessage(), e);
    }

    return sdk;
  }

  public static void checkInterpreterPathValid(@Nullable final String path) throws RakeTasksBuildService.MyBuildFailureException {
    if (path == null || StringUtil.isEmptyOrSpaces(path) || !FileUtil2.checkIfExists(path)) {
      throwInterpreterDoesntExistError(path);
    }
  }

  @NotNull
  public static File findSystemInterpreterExecutable(@NotNull final Map<String, String> envVariables)
    throws RakeTasksBuildService.MyBuildFailureException {
    // find in $PATH
    final String path = OSUtil.findRubyInterpreterInPATH(envVariables);

    if (path == null) {
      throw new RakeTasksBuildService.MyBuildFailureException("Unable to find Ruby interpreter in PATH.");
    }

    return new File(path);
  }


  @NotNull
  private static <T> T throwInterpreterDoesntExistError(@Nullable final String rubyInterpreterPath)
    throws RakeTasksBuildService.MyBuildFailureException {
    final String msg = "Ruby interpreter '"
                       + String.valueOf(rubyInterpreterPath)
                       + "' doesn't exist or isn't a file or isn't a valid RVM interpreter name.";
    throw new RakeTasksBuildService.MyBuildFailureException(msg);
  }

  public static String getRubyInterpreterVersion(@NotNull final RubySdk sdk,
                                                 @Nullable final Map<String, String> env) {
    final ExecResult result = sdk.getScriptRunner().run(RUBY_VERSION_SCRIPT, getTempDirectory(), env);
    return result.getStdout();
  }

  public static boolean isJRubyInterpreter(@NotNull final RubySdk sdk,
                                           @Nullable final Map<String, String> env) {
    if (sdk.getRubyExecutable().getName().startsWith("jruby")) {
      return true;
    }
    final ExecResult rubyPlatformResult = sdk.getScriptRunner().run(RUBY_PLATFORM_SCRIPT, getTempDirectory(), env);
    final String stdOut = rubyPlatformResult.getStdout();
    return stdOut.contains("java");
  }

  public static ExecResult getLoadPaths(@NotNull final RubySdk sdk,
                                        @Nullable final Map<String, String> env) {
    // LOAD_PATH way
    if (sdk.isRuby19()) {
      // filter gem paths in case of Ruby 1.9 (use --disable-gems)
      return sdk.getScriptRunner().run(GET_LOAD_PATH_SCRIPT, getTempDirectory(), env, RUBY19_DISABLE_GEMS_OPTION);
    } else {
      return sdk.getScriptRunner().run(GET_LOAD_PATH_SCRIPT, getTempDirectory(), env);
    }
  }

  public static ExecResult getGemPaths(@NotNull final RubySdk sdk,
                                       @Nullable final Map<String, String> env) {
    return sdk.getScriptRunner().run(RubySDKUtil.GET_GEM_PATHS_SCRIPT, getTempDirectory(), env);
  }
}