/*
 * The contents of this file are subject to the terms of the Common Development and
 * Distribution License (the License). You may not use this file except in compliance with the
 * License.
 *
 * You can obtain a copy of the License at legal/CDDLv1.0.txt. See the License for the
 * specific language governing permission and limitations under the License.
 *
 * When distributing Covered Software, include this CDDL Header Notice in each file and include
 * the License file at legal/CDDLv1.0.txt. If applicable, add the following below the CDDL
 * Header, with the fields enclosed by brackets [] replaced by your own identifying
 * information: "Portions Copyright [year] [name of copyright owner]".
 *
 * Copyright 2006-2009 Sun Microsystems, Inc.
 * Portions Copyright 2012-2016 ForgeRock AS.
 */
package org.opends.server.tools;

import static org.opends.messages.ToolMessages.*;
import static org.opends.server.config.ConfigConstants.*;
import static org.opends.server.util.StaticUtils.*;
import static com.forgerock.opendj.cli.ArgumentConstants.*;
import static com.forgerock.opendj.cli.CommonArguments.*;
import static com.forgerock.opendj.cli.Utils.*;

import java.io.OutputStream;
import java.io.PrintStream;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.forgerock.i18n.slf4j.LocalizedLogger;
import org.forgerock.opendj.ldap.DN;
import org.forgerock.opendj.ldap.schema.AttributeType;
import org.forgerock.opendj.server.config.server.BackendCfg;
import org.opends.server.api.LocalBackend;
import org.opends.server.api.LocalBackend.BackendOperation;
import org.opends.server.api.plugin.PluginType;
import org.opends.server.core.DirectoryServer;
import org.opends.server.core.LockFileManager;
import org.opends.server.loggers.JDKLogging;
import org.opends.server.protocols.ldap.LDAPAttribute;
import org.opends.server.tasks.ExportTask;
import org.opends.server.tools.tasks.TaskTool;
import org.opends.server.types.DirectoryException;
import org.opends.server.types.ExistingFileBehavior;
import org.opends.server.types.InitializationException;
import org.opends.server.types.LDIFExportConfig;
import org.opends.server.types.NullOutputStream;
import org.opends.server.types.RawAttribute;
import org.opends.server.types.SearchFilter;
import org.opends.server.util.cli.LDAPConnectionArgumentParser;

import com.forgerock.opendj.cli.Argument;
import com.forgerock.opendj.cli.ArgumentException;
import com.forgerock.opendj.cli.BooleanArgument;
import com.forgerock.opendj.cli.ClientException;
import com.forgerock.opendj.cli.IntegerArgument;
import com.forgerock.opendj.cli.StringArgument;

/**
 * This program provides a utility that may be used to export the contents of a
 * Directory Server backend to an LDIF file.  Depending on the arguments given,
 * this program will either perform the export directly as a process that
 * runs separate from Directory Server; or by scheduling a task to perform the
 * action within the Directory Server via the tasks interface.
 */
public class ExportLDIF extends TaskTool {

  private static final LocalizedLogger logger = LocalizedLogger.getLoggerForThisClass();

  /**
   * The main method for ExportLDIF tool.
   *
   * @param  args  The command-line arguments provided to this program.
   */
  public static void main(String[] args)
  {
    int retCode = mainExportLDIF(args, true, System.out, System.err);
    if(retCode != 0)
    {
      System.exit(filterExitCode(retCode));
    }
  }

  /**
   * Processes the command-line arguments and invokes the export process.
   *
   * @param  args              The command-line arguments provided to this
   *                           program.
   * @param  initializeServer  Indicates whether to initialize the server.
   * @param  outStream         The output stream to use for standard output, or
   *                           {@code null} if standard output is not needed.
   * @param  errStream         The output stream to use for standard error, or
   *                           {@code null} if standard error is not needed.
   *
   * @return The error code.
   */
  public static int mainExportLDIF(String[] args, boolean initializeServer,
                                   OutputStream outStream,
                                   OutputStream errStream)
  {
    ExportLDIF tool = new ExportLDIF();
    return tool.process(args, initializeServer, outStream, errStream);
  }

  /** Define the command-line arguments that may be used with this program. */
  private BooleanArgument appendToLDIF;
  private BooleanArgument compressLDIF;
  private BooleanArgument displayUsage;
  private BooleanArgument encryptLDIF;
  private BooleanArgument excludeOperationalAttrs;
  private BooleanArgument signHash;
  private IntegerArgument wrapColumn;
  private StringArgument  backendID;
  private StringArgument  configFile;
  private StringArgument  excludeAttributeStrings;
  private StringArgument  excludeBranchStrings;
  private StringArgument  excludeFilterStrings;
  private StringArgument  includeAttributeStrings;
  private StringArgument  includeBranchStrings;
  private StringArgument  includeFilterStrings;
  private StringArgument  ldifFile;

  private int process(String[] args, boolean initializeServer,
                      OutputStream outStream, OutputStream errStream) {

    PrintStream out = NullOutputStream.wrapOrNullStream(outStream);
    PrintStream err = NullOutputStream.wrapOrNullStream(errStream);
    JDKLogging.disableLogging();

    // Create the command-line argument parser for use with this program.
    LDAPConnectionArgumentParser argParser =
            createArgParser("org.opends.server.tools.ExportLDIF",
                            INFO_LDIFEXPORT_TOOL_DESCRIPTION.get());
    argParser.setShortToolDescription(REF_SHORT_DESC_EXPORT_LDIF.get());


    // Initialize all the command-line argument types and register them with the parser.
    try
    {
      configFile =
              StringArgument.builder("configFile")
                      .shortIdentifier('f')
                      .description(INFO_DESCRIPTION_CONFIG_FILE.get())
                      .hidden()
                      .required()
                      .valuePlaceholder(INFO_CONFIGFILE_PLACEHOLDER.get())
                      .buildAndAddToParser(argParser);
      ldifFile =
              StringArgument.builder(OPTION_LONG_LDIF_FILE)
                      .shortIdentifier(OPTION_SHORT_LDIF_FILE)
                      .description(INFO_LDIFEXPORT_DESCRIPTION_LDIF_FILE.get())
                      .required()
                      .valuePlaceholder(INFO_LDIFFILE_PLACEHOLDER.get())
                      .buildAndAddToParser(argParser);
      appendToLDIF =
              BooleanArgument.builder("appendToLDIF")
                      .shortIdentifier('a')
                      .description(INFO_LDIFEXPORT_DESCRIPTION_APPEND_TO_LDIF.get())
                      .buildAndAddToParser(argParser);
      backendID =
              StringArgument.builder("backendID")
                      .shortIdentifier('n')
                      .description(INFO_LDIFEXPORT_DESCRIPTION_BACKEND_ID.get())
                      .required()
                      .valuePlaceholder(INFO_BACKENDNAME_PLACEHOLDER.get())
                      .buildAndAddToParser(argParser);
      includeBranchStrings =
              StringArgument.builder("includeBranch")
                      .shortIdentifier('b')
                      .description(INFO_LDIFEXPORT_DESCRIPTION_INCLUDE_BRANCH.get())
                      .multiValued()
                      .valuePlaceholder(INFO_BRANCH_DN_PLACEHOLDER.get())
                      .buildAndAddToParser(argParser);
      excludeBranchStrings =
              StringArgument.builder("excludeBranch")
                      .shortIdentifier('B')
                      .description(INFO_LDIFEXPORT_DESCRIPTION_EXCLUDE_BRANCH.get())
                      .multiValued()
                      .valuePlaceholder(INFO_BRANCH_DN_PLACEHOLDER.get())
                      .buildAndAddToParser(argParser);
      includeAttributeStrings =
              StringArgument.builder("includeAttribute")
                      .shortIdentifier('i')
                      .description(INFO_LDIFEXPORT_DESCRIPTION_INCLUDE_ATTRIBUTE.get())
                      .multiValued()
                      .valuePlaceholder(INFO_ATTRIBUTE_PLACEHOLDER.get())
                      .buildAndAddToParser(argParser);
      excludeAttributeStrings =
              StringArgument.builder("excludeAttribute")
                      .shortIdentifier('e')
                      .description(INFO_LDIFEXPORT_DESCRIPTION_EXCLUDE_ATTRIBUTE.get())
                      .multiValued()
                      .valuePlaceholder(INFO_ATTRIBUTE_PLACEHOLDER.get())
                      .buildAndAddToParser(argParser);
      includeFilterStrings =
              StringArgument.builder("includeFilter")
                      .shortIdentifier('I')
                      .description(INFO_LDIFEXPORT_DESCRIPTION_INCLUDE_FILTER.get())
                      .multiValued()
                      .valuePlaceholder(INFO_FILTER_PLACEHOLDER.get())
                      .buildAndAddToParser(argParser);
      excludeFilterStrings =
              StringArgument.builder("excludeFilter")
                      .shortIdentifier('E')
                      .description(INFO_LDIFEXPORT_DESCRIPTION_EXCLUDE_FILTER.get())
                      .multiValued()
                      .valuePlaceholder(INFO_FILTER_PLACEHOLDER.get())
                      .buildAndAddToParser(argParser);
      excludeOperationalAttrs =
              BooleanArgument.builder("excludeOperational")
                      .shortIdentifier('O')
                      .description(INFO_LDIFEXPORT_DESCRIPTION_EXCLUDE_OPERATIONAL.get())
                      .buildAndAddToParser(argParser);
      wrapColumn =
              IntegerArgument.builder("wrapColumn")
                      .description(INFO_LDIFEXPORT_DESCRIPTION_WRAP_COLUMN.get())
                      .lowerBound(0)
                      .defaultValue(0)
                      .valuePlaceholder(INFO_WRAP_COLUMN_PLACEHOLDER.get())
                      .buildAndAddToParser(argParser);
      compressLDIF =
              BooleanArgument.builder(OPTION_LONG_COMPRESS)
                      .shortIdentifier(OPTION_SHORT_COMPRESS)
                      .description(INFO_LDIFEXPORT_DESCRIPTION_COMPRESS_LDIF.get())
                      .buildAndAddToParser(argParser);
      encryptLDIF =
              BooleanArgument.builder("encryptLDIF")
                      .shortIdentifier('y')
                      .description(INFO_LDIFEXPORT_DESCRIPTION_ENCRYPT_LDIF.get())
                      .hidden() // See issue OPENDJ-448
                      .buildAndAddToParser(argParser);
      signHash =
              BooleanArgument.builder("signHash")
                      .shortIdentifier('s')
                      .description(INFO_LDIFEXPORT_DESCRIPTION_SIGN_HASH.get())
                      .hidden() // See issue OPENDJ-448
                      .buildAndAddToParser(argParser);

      displayUsage = showUsageArgument();
      argParser.addArgument(displayUsage);
      argParser.setUsageArgument(displayUsage);
    }
    catch (ArgumentException ae)
    {
      printWrappedText(err, ERR_CANNOT_INITIALIZE_ARGS.get(ae.getMessage()));
      return 1;
    }


    // Init the default values so that they can appear also on the usage.
    argParser.getArguments().initArgumentsWithConfiguration(argParser);

    // Parse the command-line arguments provided to this program.
    try
    {
      argParser.parseArguments(args);
      validateTaskArgs();
    }
    catch (ArgumentException ae)
    {
      argParser.displayMessageAndUsageReference(err, ERR_ERROR_PARSING_ARGS.get(ae.getMessage()));
      return 1;
    }
    catch (ClientException ce)
    {
      // No need to display the usage since the problem comes with a provided value.
      printWrappedText(err, ce.getMessageObject());
      return 1;
    }


    // If we should just display usage or version information,
    // then print it and exit.
    if (argParser.usageOrVersionDisplayed())
    {
      return 0;
    }

    // Checks the version - if upgrade required, the tool is unusable
    try
    {
      checkVersion();
    }
    catch (InitializationException e)
    {
      printWrappedText(err, e.getMessage());
      return 1;
    }

    return process(argParser, initializeServer, out, err);
  }

  @Override
  public void addTaskAttributes(List<RawAttribute> attributes)
  {
    // Required attributes
    attributes.add(new LDAPAttribute(ATTR_TASK_EXPORT_LDIF_FILE, ldifFile.getValue()));
    attributes.add(new LDAPAttribute(ATTR_TASK_EXPORT_BACKEND_ID, backendID.getValue()));

    // Optional attributes
    addAttribute(attributes, ATTR_TASK_EXPORT_APPEND_TO_LDIF, appendToLDIF);
    addAttribute(attributes, ATTR_TASK_EXPORT_COMPRESS_LDIF, compressLDIF);
    addAttribute(attributes, ATTR_TASK_EXPORT_ENCRYPT_LDIF, encryptLDIF);
    addAttribute(attributes, ATTR_TASK_EXPORT_SIGN_HASH, signHash);
    addAttribute(attributes, ATTR_TASK_EXPORT_INCLUDE_ATTRIBUTE, includeAttributeStrings.getValues());
    addAttribute(attributes, ATTR_TASK_EXPORT_EXCLUDE_ATTRIBUTE, excludeAttributeStrings.getValues());
    addAttribute(attributes, ATTR_TASK_EXPORT_INCLUDE_FILTER, includeFilterStrings.getValues());
    addAttribute(attributes, ATTR_TASK_EXPORT_EXCLUDE_FILTER, excludeFilterStrings.getValues());
    addAttribute(attributes, ATTR_TASK_EXPORT_INCLUDE_BRANCH, includeBranchStrings.getValues());
    addAttribute(attributes, ATTR_TASK_EXPORT_EXCLUDE_BRANCH, excludeBranchStrings.getValues());
    addAttribute(attributes, ATTR_TASK_EXPORT_WRAP_COLUMN, wrapColumn);

    if (excludeOperationalAttrs.isPresent())
    {
      attributes.add(
          new LDAPAttribute(ATTR_TASK_EXPORT_INCLUDE_OPERATIONAL_ATTRIBUTES, "false"));
    }
  }

  private void addAttribute(List<RawAttribute> attributes, String attrName, Argument arg)
  {
    if (arg.getValue() != null && !arg.getValue().equals(arg.getDefaultValue()))
    {
      attributes.add(new LDAPAttribute(attrName, arg.getValue()));
    }
  }

  private void addAttribute(List<RawAttribute> attributes, String attrName, List<String> attrValues)
  {
    if (attrValues != null && !attrValues.isEmpty())
    {
      attributes.add(new LDAPAttribute(attrName, attrValues));
    }
  }

  @Override
  public String getTaskObjectclass() {
    return "ds-task-export";
  }

  @Override
  public Class<?> getTaskClass() {
    return ExportTask.class;
  }

  @Override
  protected int processLocal(boolean initializeServer, PrintStream out, PrintStream err)
  {
    if (initializeServer)
    {
      try
      {
        new DirectoryServer.InitializationBuilder(configFile.getValue())
            .requireCryptoServices()
            .requireUserPlugins(PluginType.LDIF_EXPORT)
            .requireErrorAndDebugLogPublisher(out, err)
            .initialize();
      }
      catch (InitializationException ie)
      {
        printWrappedText(err, ERR_CANNOT_INITIALIZE_SERVER_COMPONENTS.get(getExceptionMessage(ie)));
        return 1;
      }
    }

    // See if there were any user-defined sets of include/exclude attributes or
    // filters.  If so, then process them.
    Set<AttributeType> excludeAttributes = toAttributeTypes(excludeAttributeStrings);
    Set<AttributeType> includeAttributes = toAttributeTypes(includeAttributeStrings);

    ArrayList<SearchFilter> excludeFilters;
    if (excludeFilterStrings == null)
    {
      excludeFilters = null;
    }
    else
    {
      excludeFilters = new ArrayList<>();
      for (String filterString : excludeFilterStrings.getValues())
      {
        try
        {
          excludeFilters.add(SearchFilter.createFilterFromString(filterString));
        }
        catch (DirectoryException de)
        {
          logger.error(ERR_LDIFEXPORT_CANNOT_PARSE_EXCLUDE_FILTER, filterString, de.getMessageObject());
          return 1;
        }
        catch (Exception e)
        {
          logger.error(ERR_LDIFEXPORT_CANNOT_PARSE_EXCLUDE_FILTER, filterString, getExceptionMessage(e));
          return 1;
        }
      }
    }

    ArrayList<SearchFilter> includeFilters;
    if (includeFilterStrings == null)
    {
      includeFilters = null;
    }
    else
    {
      includeFilters = new ArrayList<>();
      for (String filterString : includeFilterStrings.getValues())
      {
        try
        {
          includeFilters.add(SearchFilter.createFilterFromString(filterString));
        }
        catch (DirectoryException de)
        {
          logger.error(ERR_LDIFEXPORT_CANNOT_PARSE_INCLUDE_FILTER, filterString, de.getMessageObject());
          return 1;
        }
        catch (Exception e)
        {
          logger.error(ERR_LDIFEXPORT_CANNOT_PARSE_INCLUDE_FILTER, filterString, getExceptionMessage(e));
          return 1;
        }
      }
    }


    // Get information about the backends defined in the server.  Iterate
    // through them, finding the one backend that should be used for the export,
    // and also finding backends with subordinate base DNs that should be
    // excluded from the export.
    LocalBackend<?>    backend                = null;
    List<DN>      baseDNList             = null;
    List<DN>      defaultIncludeBranches = null;
    ArrayList<DN> excludeBranches        = null;

    List<LocalBackend<?>> backendList = new ArrayList<>();
    List<BackendCfg> entryList = new ArrayList<>();
    List<List<DN>> dnList = new ArrayList<>();
    BackendToolUtils.getBackends(backendList, entryList, dnList);

    int numBackends = backendList.size();
    for (int i=0; i < numBackends; i++)
    {
      LocalBackend<?> b = backendList.get(i);
      if (! backendID.getValue().equals(b.getBackendID()))
      {
        continue;
      }

      if (backend == null)
      {
        backend                = b;
        baseDNList             = dnList.get(i);
        defaultIncludeBranches = dnList.get(i);
      }
      else
      {
        logger.error(ERR_LDIFEXPORT_MULTIPLE_BACKENDS_FOR_ID, backendID.getValue());
        return 1;
      }
    }

    if (backend == null)
    {
      logger.error(ERR_LDIFEXPORT_NO_BACKENDS_FOR_ID, backendID.getValue());
      return 1;
    }
    else if (!backend.supports(BackendOperation.RESTORE))
    {
      logger.error(ERR_LDIFEXPORT_CANNOT_EXPORT_BACKEND, backendID.getValue());
      return 1;
    }

    if (excludeBranchStrings.isPresent())
    {
      excludeBranches = new ArrayList<>();
      for (String s : excludeBranchStrings.getValues())
      {
        DN excludeBranch;
        try
        {
          excludeBranch = DN.valueOf(s);
        }
        catch (Exception e)
        {
          logger.error(ERR_LDIFEXPORT_CANNOT_DECODE_EXCLUDE_BASE, s, getExceptionMessage(e));
          return 1;
        }

        if (! excludeBranches.contains(excludeBranch))
        {
          excludeBranches.add(excludeBranch);
        }
      }
    }


    List<DN> includeBranches;
    if (includeBranchStrings.isPresent())
    {
      includeBranches = new ArrayList<>();
      for (String s : includeBranchStrings.getValues())
      {
        DN includeBranch;
        try
        {
          includeBranch = DN.valueOf(s);
        }
        catch (Exception e)
        {
          logger.error(ERR_LDIFIMPORT_CANNOT_DECODE_INCLUDE_BASE, s, getExceptionMessage(e));
          return 1;
        }

        if (! LocalBackend.handlesEntry(includeBranch, defaultIncludeBranches,
                                   excludeBranches))
        {
          logger.error(ERR_LDIFEXPORT_INVALID_INCLUDE_BASE, s, backendID.getValue());
          return 1;
        }

        includeBranches.add(includeBranch);
      }
    }
    else
    {
      includeBranches = defaultIncludeBranches;
    }


    // Create the LDIF export configuration to use when reading the LDIF.
    ExistingFileBehavior existingBehavior;
    if (appendToLDIF.isPresent())
    {
      existingBehavior = ExistingFileBehavior.APPEND;
    }
    else
    {
      existingBehavior = ExistingFileBehavior.OVERWRITE;
    }

    LDIFExportConfig exportConfig = new LDIFExportConfig(ldifFile.getValue(),
                                                         existingBehavior);
    exportConfig.setCompressData(compressLDIF.isPresent());
    exportConfig.setEncryptData(encryptLDIF.isPresent());
    exportConfig.setExcludeAttributes(excludeAttributes);
    exportConfig.setExcludeBranches(excludeBranches);
    exportConfig.setExcludeFilters(excludeFilters);
    exportConfig.setIncludeAttributes(includeAttributes);
    exportConfig.setIncludeBranches(includeBranches);
    exportConfig.setIncludeFilters(includeFilters);
    exportConfig.setSignHash(signHash.isPresent());
    exportConfig.setIncludeOperationalAttributes(
                      !excludeOperationalAttrs.isPresent());

    // FIXME -- Should this be conditional?
    exportConfig.setInvokeExportPlugins(true);

    try
    {
      exportConfig.setWrapColumn(wrapColumn.getIntValue());
    }
    catch (ArgumentException ae)
    {
      logger.error(ERR_LDIFEXPORT_CANNOT_DECODE_WRAP_COLUMN_AS_INTEGER, wrapColumn.getValue());
      return 1;
    }


    // Get the set of base DNs for the backend as an array.
    DN[] baseDNs = new DN[baseDNList.size()];
    baseDNList.toArray(baseDNs);


    // Acquire a shared lock for the backend.
    try
    {
      String lockFile = LockFileManager.getBackendLockFileName(backend);
      StringBuilder failureReason = new StringBuilder();
      if (! LockFileManager.acquireSharedLock(lockFile, failureReason))
      {
        logger.error(ERR_LDIFEXPORT_CANNOT_LOCK_BACKEND, backend.getBackendID(), failureReason);
        return 1;
      }
    }
    catch (Exception e)
    {
      logger.error(ERR_LDIFEXPORT_CANNOT_LOCK_BACKEND, backend.getBackendID(), getExceptionMessage(e));
      return 1;
    }

    boolean errorOccurred = false;

    // Launch the export.
    try
    {
      backend.exportLDIF(exportConfig);
    }
    catch (DirectoryException de)
    {
      logger.error(ERR_LDIFEXPORT_ERROR_DURING_EXPORT, de.getMessageObject());
      errorOccurred = true;
    }
    catch (Exception e)
    {
      logger.error(ERR_LDIFEXPORT_ERROR_DURING_EXPORT, getExceptionMessage(e));
      errorOccurred = true;
    }


    // Release the shared lock on the backend.
    try
    {
      String lockFile = LockFileManager.getBackendLockFileName(backend);
      StringBuilder failureReason = new StringBuilder();
      if (! LockFileManager.releaseLock(lockFile, failureReason))
      {
        logger.warn(WARN_LDIFEXPORT_CANNOT_UNLOCK_BACKEND, backend.getBackendID(), failureReason);
      }
    }
    catch (Exception e)
    {
      logger.warn(WARN_LDIFEXPORT_CANNOT_UNLOCK_BACKEND, backend.getBackendID(), getExceptionMessage(e));
    }


    // Clean up after the export by closing the export config.
    exportConfig.close();
    return !errorOccurred ? 0 : 1;
  }

  @Override
  protected void cleanup()
  {
    DirectoryServer.getInstance().getServerContext().getBackendConfigManager().shutdownLocalBackends();
  }

  private Set<AttributeType> toAttributeTypes(StringArgument attributeArg)
  {
    if (attributeArg == null)
    {
      return null;
    }

    Set<AttributeType> results = new HashSet<>();
    for (String attrName : attributeArg.getValues())
    {
      results.add(DirectoryServer.getInstance().getServerContext().getSchema().getAttributeType(attrName));
    }
    return results;
  }

  @Override
  public String getTaskId() {
    // NYI.
    return null;
  }
}