/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at
 * trunk/opends/resource/legal-notices/OpenDS.LICENSE
 * or https://OpenDS.dev.java.net/OpenDS.LICENSE.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at
 * trunk/opends/resource/legal-notices/OpenDS.LICENSE.  If applicable,
 * add the following below this CDDL HEADER, with the fields enclosed
 * by brackets "[]" replaced with your own identifying information:
 *      Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 *
 *
 *      Copyright 2006-2008 Sun Microsystems, Inc.
 */
package com.sun.opends.sdk.tools;



import static com.sun.opends.sdk.messages.Messages.*;
import static com.sun.opends.sdk.util.StaticUtils.getExceptionMessage;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.util.LinkedHashMap;

import org.opends.sdk.LocalizableMessage;
import org.opends.sdk.LocalizableMessageBuilder;



/**
 * This class defines an argument whose value will be read from a file rather
 * than actually specified on the command-line. When a value is specified on the
 * command line, it will be treated as the path to the file containing the
 * actual value rather than the value itself. <BR>
 * <BR>
 * Note that if if no filename is provided on the command line but a default
 * value is specified programatically or if the default value is read from a
 * specified property, then that default value will be taken as the actual value
 * rather than a filename. <BR>
 * <BR>
 * Also note that this argument type assumes that the entire value for the
 * argument is on a single line in the specified file. If the file contains
 * multiple lines, then only the first line will be read.
 */
final class FileBasedArgument extends Argument
{
  // The mapping between filenames specified and the first lines read
  // from those
  // files.
  private final LinkedHashMap<String, String> namesToValues;



  /**
   * Creates a new file-based argument with the provided information.
   *
   * @param name
   *          The generic name that should be used to refer to this argument.
   * @param shortIdentifier
   *          The single-character identifier for this argument, or
   *          <CODE>null</CODE> if there is none.
   * @param longIdentifier
   *          The long identifier for this argument, or <CODE>null</CODE> if
   *          there is none.
   * @param isRequired
   *          Indicates whether this argument must be specified on the command
   *          line.
   * @param isMultiValued
   *          Indicates whether this argument may be specified more than once to
   *          provide multiple values.
   * @param valuePlaceholder
   *          The placeholder for the argument value that will be displayed in
   *          usage information, or <CODE>null</CODE> if this argument does not
   *          require a value.
   * @param defaultValue
   *          The default value that should be used for this argument if none is
   *          provided in a properties file or on the command line. This may be
   *          <CODE>null</CODE> if there is no generic default.
   * @param propertyName
   *          The name of the property in a property file that may be used to
   *          override the default value but will be overridden by a
   *          command-line argument.
   * @param description
   *          LocalizableMessage for the description of this argument.
   * @throws ArgumentException
   *           If there is a problem with any of the parameters used to create
   *           this argument.
   */
  public FileBasedArgument(final String name, final Character shortIdentifier,
      final String longIdentifier, final boolean isRequired,
      final boolean isMultiValued, final LocalizableMessage valuePlaceholder,
      final String defaultValue, final String propertyName,
      final LocalizableMessage description) throws ArgumentException
  {
    super(name, shortIdentifier, longIdentifier, isRequired, isMultiValued,
        true, valuePlaceholder, defaultValue, propertyName, description);

    namesToValues = new LinkedHashMap<String, String>();
  }



  /**
   * Creates a new file-based argument with the provided information.
   *
   * @param name
   *          The generic name that should be used to refer to this argument.
   * @param shortIdentifier
   *          The single-character identifier for this argument, or
   *          <CODE>null</CODE> if there is none.
   * @param longIdentifier
   *          The long identifier for this argument, or <CODE>null</CODE> if
   *          there is none.
   * @param isRequired
   *          Indicates whether this argument must be specified on the command
   *          line.
   * @param valuePlaceholder
   *          The placeholder for the argument value that will be displayed in
   *          usage information, or <CODE>null</CODE> if this argument does not
   *          require a value.
   * @param description
   *          LocalizableMessage for the description of this argument.
   * @throws ArgumentException
   *           If there is a problem with any of the parameters used to create
   *           this argument.
   */
  public FileBasedArgument(final String name, final Character shortIdentifier,
      final String longIdentifier, final boolean isRequired,
      final LocalizableMessage valuePlaceholder,
      final LocalizableMessage description) throws ArgumentException
  {
    super(name, shortIdentifier, longIdentifier, isRequired, false, true,
        valuePlaceholder, null, null, description);

    namesToValues = new LinkedHashMap<String, String>();
  }



  /**
   * Adds a value to the set of values for this argument. This should only be
   * called if the value is allowed by the <CODE>valueIsAcceptable</CODE>
   * method. Note that in this case, correct behavior depends on a previous
   * successful call to <CODE>valueIsAcceptable</CODE> so that the value read
   * from the file may be stored in the name-to-value hash and used in place of
   * the filename here.
   *
   * @param valueString
   *          The string representation of the value to add to this argument.
   */
  @Override
  public void addValue(final String valueString)
  {
    final String actualValue = namesToValues.get(valueString);
    if (actualValue != null)
    {
      super.addValue(actualValue);
    }
  }



  /**
   * Retrieves a map between the filenames specified on the command line and the
   * first lines read from those files.
   *
   * @return A map between the filenames specified on the command line and the
   *         first lines read from those files.
   */
  public LinkedHashMap<String, String> getNameToValueMap()
  {
    return namesToValues;
  }



  /**
   * Indicates whether the provided value is acceptable for use in this
   * argument.
   *
   * @param valueString
   *          The value for which to make the determination.
   * @param invalidReason
   *          A buffer into which the invalid reason may be written if the value
   *          is not acceptable.
   * @return <CODE>true</CODE> if the value is acceptable, or <CODE>false</CODE>
   *         if it is not.
   */
  @Override
  public boolean valueIsAcceptable(final String valueString,
      final LocalizableMessageBuilder invalidReason)
  {
    // First, make sure that the specified file exists.
    File valueFile;
    try
    {
      valueFile = new File(valueString);
      if (!valueFile.exists())
      {
        invalidReason.append(ERR_FILEARG_NO_SUCH_FILE.get(valueString,
            getName()));
        return false;
      }
    }
    catch (final Exception e)
    {
      invalidReason.append(ERR_FILEARG_CANNOT_VERIFY_FILE_EXISTENCE.get(
          valueString, getName(), getExceptionMessage(e)));
      return false;
    }

    // Open the file for reading.
    BufferedReader reader;
    try
    {
      reader = new BufferedReader(new FileReader(valueFile));
    }
    catch (final Exception e)
    {
      invalidReason.append(ERR_FILEARG_CANNOT_OPEN_FILE.get(valueString,
          getName(), getExceptionMessage(e)));
      return false;
    }

    // Read the first line and close the file.
    String line;
    try
    {
      line = reader.readLine();
    }
    catch (final Exception e)
    {
      invalidReason.append(ERR_FILEARG_CANNOT_READ_FILE.get(valueString,
          getName(), getExceptionMessage(e)));
      return false;
    }
    finally
    {
      try
      {
        reader.close();
      }
      catch (final Exception e)
      {
      }
    }

    // If the line read is null, then that means the file was empty.
    if (line == null)
    {

      invalidReason.append(ERR_FILEARG_EMPTY_FILE.get(valueString, getName()));
      return false;
    }

    // Store the value in the hash so it will be available for addValue.
    // We
    // won't do any validation on the value itself, so anything that we
    // read
    // will be considered acceptable.
    namesToValues.put(valueString, line);
    return true;
  }
}