/*
 * 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
 *
 *
 *      Portions Copyright 2007 Sun Microsystems, Inc.
 */

package org.opends.quicksetup;

import org.opends.admin.ads.ADSContext;
import org.opends.admin.ads.ServerDescriptor;
import org.opends.admin.ads.TopologyCacheException;
import org.opends.admin.ads.util.ApplicationTrustManager;
import org.opends.admin.ads.util.ServerLoader;
import org.opends.quicksetup.event.ProgressNotifier;
import org.opends.quicksetup.event.ProgressUpdateListener;
import org.opends.quicksetup.util.ServerController;
import org.opends.quicksetup.util.Utils;
import org.opends.quicksetup.util.ProgressMessageFormatter;
import org.opends.quicksetup.i18n.ResourceProvider;
import org.opends.quicksetup.ui.GuiApplication;

import java.io.PrintStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.naming.NamingException;
import javax.naming.ldap.InitialLdapContext;

/**
 * This class represents an application that can be run in the context of
 * QuickSetup.  Examples of applications might be 'installer', 'uninstaller'
 * and 'upgrader'.
 */
public abstract class Application implements ProgressNotifier, Runnable {

  static private final Logger LOG =
          Logger.getLogger(Application.class.getName());

  /** Represents current install state. */
  protected CurrentInstallStatus installStatus;

  private UserData userData;

  private Installation installation;

  private ServerController serverController;

  private ApplicationTrustManager trustManager;

  /** Formats progress messages. */
  protected ProgressMessageFormatter formatter;

  /** Handler for listeners and event firing. */
  protected ProgressUpdateListenerDelegate listenerDelegate;

  /**
   * Creates an application by instantiating the Application class
   * denoted by the System property
   * <code>org.opends.quicksetup.Application.class</code>.
   * @return Application object that was newly instantiated
   * @throws RuntimeException if there was a problem
   *  creating the new Application object
   */
  static public GuiApplication create()
          throws RuntimeException {
    GuiApplication app;
    String appClassName =
            System.getProperty("org.opends.quicksetup.Application.class");
    if (appClassName != null) {
      Class appClass = null;
      try {
        appClass = Class.forName(appClassName);
        app = (GuiApplication) appClass.newInstance();
      } catch (ClassNotFoundException e) {
        LOG.log(Level.INFO, "error creating quicksetup application", e);
        String msg = "Application class " + appClass + " not found";
        throw new RuntimeException(msg, e);
      } catch (IllegalAccessException e) {
        LOG.log(Level.INFO, "error creating quicksetup application", e);
        String msg = "Could not access class " + appClass;
        throw new RuntimeException(msg, e);
      } catch (InstantiationException e) {
        LOG.log(Level.INFO, "error creating quicksetup application", e);
        String msg = "Error instantiating class " + appClass;
        throw new RuntimeException(msg, e);
      } catch (ClassCastException e) {
        String msg = "The class indicated by the system property " +
                  "'org.opends.quicksetup.Application.class' must " +
                  " must be of type Application";
        throw new RuntimeException(msg, e);
      }
    } else {
      String msg = "System property 'org.opends.quicksetup.Application.class'" +
                " must specify class quicksetup application";
      throw new RuntimeException(msg);
    }
    return app;
  }

  /**
   * Sets this instances user data.
   * @param userData UserData this application will use
   *        when executing
   */
  public void setUserData(UserData userData) {
    this.userData = userData;
  }

  /**
   * Creates a set of user data with default values.
   * @return UserData empty set of UserData
   */
  public UserData createUserData() {
    return new UserData();
  }

  /**
   * Adds a ProgressUpdateListener that will be notified of updates in
   * the install progress.
   * @param l the ProgressUpdateListener to be added.
   */
  public void addProgressUpdateListener(ProgressUpdateListener l)
  {
    listenerDelegate.addProgressUpdateListener(l);
  }

  /**
   * Removes a ProgressUpdateListener.
   * @param l the ProgressUpdateListener to be removed.
   */
  public void removeProgressUpdateListener(ProgressUpdateListener l)
  {
    listenerDelegate.removeProgressUpdateListener(l);
  }

  /**
   * Gets the OpenDS installation associated with the execution of this
   * command.
   * @return Installation object representing the current OpenDS installation
   */
  public Installation getInstallation() {
    if (installation == null) {
      String installPath = getInstallationPath();
      if (installPath != null) {
        installation = new Installation(installPath);
      }
    }
    return installation;
  }

  /**
   * Sets the application's installation.
   * @param installation describing the application's OpenDS installation
   */
  public void setInstallation(Installation installation) {
    this.installation = installation;
  }

  /**
   * Gets a server controller for use by this application.
   * @return ServerController that can be used to start and stop the server.
   */
  public ServerController getServerController() {
    if (serverController == null) {
      serverController = new ServerController(this);
    }
    return serverController;
  }

  /**
   * Returns the UserData object representing the parameters provided by
   * the user to do the installation.
   *
   * @return the UserData object representing the parameters provided
   * by the user to do the installation.
   */
  public UserData getUserData()
  {
    if (userData == null) {
      userData = createUserData();
    }
    return userData;
  }

  /**
   * This method notifies the ProgressUpdateListeners that there was an
   * update in the installation progress.
   * @param ratioWhenCompleted the integer that specifies which percentage of
   * the whole installation has been completed.
   */
  public void notifyListenersDone(Integer ratioWhenCompleted) {
    notifyListeners(ratioWhenCompleted,
            getSummary(getCurrentProgressStep()),
            formatter.getFormattedDone() + formatter.getLineBreak());
  }

  /**
   * This method notifies the ProgressUpdateListeners that there was an
   * update in the installation progress.
   * @param ratio the integer that specifies which percentage of
   * the whole installation has been completed.
   * @param currentPhaseSummary the localized summary message for the
   * current installation progress in formatted form.
   * @param newLogDetail the new log messages that we have for the
   * installation in formatted form.
   */
  public void notifyListeners(Integer ratio, String currentPhaseSummary,
      String newLogDetail)
  {
    listenerDelegate.notifyListeners(getCurrentProgressStep(),
            ratio, currentPhaseSummary, newLogDetail);
  }

  /**
   * This method notifies the ProgressUpdateListeners that there was an
   * update in the installation progress.
   * @param ratio the integer that specifies which percentage of
   * the whole installation has been completed.
   * @param currentPhaseSummary the localized summary message for the
   * current installation progress in formatted form.
   */
  public void notifyListeners(Integer ratio, String currentPhaseSummary) {
    notifyListeners(ratio, getSummary(getCurrentProgressStep()),
        formatter.getFormattedWithPoints(currentPhaseSummary));
  }

  /**
   * Returns a localized message for a key value.  In  the properties file we
   * have something of type:
   * key=value
   *
   * @see org.opends.quicksetup.i18n.ResourceProvider#getMsg(String)
   * @param key the key in the properties file.
   * @return the value associated to the key in the properties file.
   * properties file.
   */
  public String getMsg(String key)
  {
    return getI18n().getMsg(key);
  }

  /**
   * Returns a localized message for a key value.  In  the properties file we
   * have something of type:
   * key=value
   *
   * For instance if we pass as key "mykey" and as arguments {"value1"} and
   * in the properties file we have:
   * mykey=value with argument {0}.
   *
   * This method will return "value with argument value1".
   * @see org.opends.quicksetup.i18n.ResourceProvider#getMsg(String, String[])
   * @param key the key in the properties file.
   * @param args the arguments to be passed to generate the resulting value.
   * @return the value associated to the key in the properties file.
   */
  public String getMsg(String key, String... args)
  {
    return getI18n().getMsg(key, args);
  }

  /**
   * Returns a ResourceProvider instance.
   * @return a ResourceProvider instance.
   */
  public ResourceProvider getI18n()
  {
    return ResourceProvider.getInstance();
  }

  /**
   * Returns a localized message for a given properties key and throwable.
   * @param key the key of the message in the properties file.
   * @param t the throwable for which we want to get a message.
   * @return a localized message for a given properties key and throwable.
   */
  public String getThrowableMsg(String key, Throwable t)
  {
    return getThrowableMsg(key, null, t);
  }

  /**
   * Returns a localized message for a given properties key and throwable.
   * @param key the key of the message in the properties file.
   * @param args the arguments of the message in the properties file.
   * @param t the throwable for which we want to get a message.
   *
   * @return a localized message for a given properties key and throwable.
   */
  protected String getThrowableMsg(String key, String[] args, Throwable t)
  {
    return Utils.getThrowableMsg(getI18n(), key, args, t);
  }

  /**
   * Sets the formatter this instance should use to used
   * to format progress messages.
   * @param formatter ProgressMessageFormatter for formatting
   * progress messages
   */
  public void setProgressMessageFormatter(ProgressMessageFormatter formatter) {
    this.formatter = formatter;
    this.listenerDelegate = new ProgressUpdateListenerDelegate(formatter);
  }

  /**
   * Gets the formatter this instance is currently using.
   * @return the progress message formatter currently used by this
   * application
   */
  public ProgressMessageFormatter getProgressMessageFormatter() {
    return formatter;
  }

  /**
   * Returns the formatted representation of the text that is the summary of the
   * installation process (the one that goes in the UI next to the progress
   * bar).
   * @param text the source text from which we want to get the formatted
   * representation
   * @return the formatted representation of an error for the given text.
   */
  protected String getFormattedSummary(String text)
  {
    return formatter.getFormattedSummary(text);
  }

  /**
   * Returns the formatted representation of an error for a given text.
   * @param text the source text from which we want to get the formatted
   * representation
   * @return the formatted representation of an error for the given text.
   */
  protected String getFormattedError(String text)
  {
    return formatter.getFormattedError(text, false);
  }

  /**
   * Returns the formatted representation of an warning for a given text.
   * @param text the source text from which we want to get the formatted
   * representation
   * @return the formatted representation of an warning for the given text.
   */
  public String getFormattedWarning(String text)
  {
    return formatter.getFormattedWarning(text, false);
  }

  /**
   * Returns the formatted representation of a success message for a given text.
   * @param text the source text from which we want to get the formatted
   * representation
   * @return the formatted representation of an success message for the given
   * text.
   */
  protected String getFormattedSuccess(String text)
  {
    return formatter.getFormattedSuccess(text);
  }

  /**
   * Returns the formatted representation of a log error message for a given
   * text.
   * @param text the source text from which we want to get the formatted
   * representation
   * @return the formatted representation of a log error message for the given
   * text.
   */
  public String getFormattedLogError(String text)
  {
    return formatter.getFormattedLogError(text);
  }

  /**
   * Returns the formatted representation of a log message for a given text.
   * @param text the source text from which we want to get the formatted
   * representation
   * @return the formatted representation of a log message for the given text.
   */
  public String getFormattedLog(String text)
  {
    return formatter.getFormattedLog(text);
  }

  /**
   * Returns the formatted representation of the 'Done' text string.
   * @return the formatted representation of the 'Done' text string.
   */
  public String getFormattedDone()
  {
    return formatter.getFormattedDone();
  }

  /**
   * Returns the formatted representation of the argument text to which we add
   * points.  For instance if we pass as argument 'Configuring Server' the
   * return value will be 'Configuring Server .....'.
   * @param text the String to which add points.
   * @return the formatted representation of the '.....' text string.
   */
  public String getFormattedWithPoints(String text)
  {
    return formatter.getFormattedWithPoints(text);
  }

  /**
   * Returns the formatted representation of a progress message for a given
   * text.
   * @param text the source text from which we want to get the formatted
   * representation
   * @return the formatted representation of a progress message for the given
   * text.
   */
  public String getFormattedProgress(String text)
  {
    return formatter.getFormattedProgress(text);
  }

  /**
   * Returns the formatted representation of an error message for a given
   * exception.
   * This method applies a margin if the applyMargin parameter is
   * <CODE>true</CODE>.
   * @param t the exception.
   * @param applyMargin specifies whether we apply a margin or not to the
   * resulting formatted text.
   * @return the formatted representation of an error message for the given
   * exception.
   */
  protected String getFormattedError(Throwable t, boolean applyMargin)
  {
    return formatter.getFormattedError(t, applyMargin);
  }

  /**
   * Returns the line break formatted.
   * @return the line break formatted.
   */
  public String getLineBreak()
  {
    return formatter.getLineBreak();
  }

  /**
   * Returns the task separator formatted.
   * @return the task separator formatted.
   */
  protected String getTaskSeparator()
  {
    return formatter.getTaskSeparator();
  }

  /**
   * This method is called when a new log message has been received.  It will
   * notify the ProgressUpdateListeners of this fact.
   * @param newLogDetail the new log detail.
   */
  public void notifyListeners(String newLogDetail)
  {
    Integer ratio = getRatio(getCurrentProgressStep());
    String currentPhaseSummary = getSummary(getCurrentProgressStep());
    notifyListeners(ratio, currentPhaseSummary, newLogDetail);
  }

  /**
   * Returns the installation path.
   * @return the installation path.
   */
  public abstract String getInstallationPath();

  /**
   * Gets the current step.
   * @return ProgressStep representing the current step
   */
  public abstract ProgressStep getCurrentProgressStep();

  /**
   * Gets an integer representing the amount of processing
   * this application still needs to perform as a ratio
   * out of 100.
   * @param step ProgressStop for which a summary is needed
   * @return ProgressStep representing the current step
   */
  public abstract Integer getRatio(ProgressStep step);

  /**
   * Gets an i18n'd string representing the summary of
   * a give ProgressStep.
   * @param step ProgressStop for which a summary is needed
   * @return String representing the summary
   */
  public abstract String getSummary(ProgressStep step);

  /**
   * Sets the current install status for this application.
   * @param installStatus for the current installation.
   */
  public void setCurrentInstallStatus(CurrentInstallStatus installStatus) {
    this.installStatus = installStatus;
  }

  /**
   * Returns whether the installer has finished or not.
   * @return <CODE>true</CODE> if the install is finished or <CODE>false
   * </CODE> if not.
   */
  abstract public boolean isFinished();

  /**
   * Returns the trust manager that can be used to establish secure connections.
   * @return the trust manager that can be used to establish secure connections.
   */
  protected ApplicationTrustManager getTrustManager()
  {
    if (trustManager == null)
    {
      trustManager = new ApplicationTrustManager(null);
    }
    return trustManager;
  }



  /**
   * Indicates whether or not this application is capable of cancelling
   * the operation performed in the run method.  A cancellable operation
   * should leave its environment in the same state as it was prior to
   * running the operation (files deleted, changes backed out etc.).
   *
   * Marking an <code>Application</code> as cancellable may control UI
   * elements like the presense of a cancel button while the operation
   * is being performed.
   *
   * Applications marked as cancellable should override the
   * <code>cancel</code> method in such a way as to undo whatever
   * actions have taken place in the run method up to that point.
   *
   * @return boolean where true inidcates that the operation is cancellable
   */
  abstract public boolean isCancellable();

  /**
   * Signals that the application should cancel a currently running
   * operation as soon as possible and return the environment to the
   * state prior to running the operation.  When finished backing
   * out changes the application should make sure that <code>isFinished</code>
   * returns true so that the application can complete.
   */
  abstract public void cancel();

  /**
   * Makes available a <code>UserInteraction</code> class that can be used
   * by the application to interact with the user.  If the user has requested
   * a silent session this method returns null.
   * @return UserInteraction object
   */
  public UserInteraction userInteraction() {
    // Note:  overridden in GuiApplication
    UserInteraction ui = null;
    if (!getUserData().isSilent()) {
      ui = new CliUserInteraction();
    }
    return ui;
  }

  /**
   * Conditionally notifies listeners of the log file if it
   * has been initialized.
   */
  protected void notifyListenersOfLog() {
    File logFile = QuickSetupLog.getLogFile();
    if (logFile != null) {
      notifyListeners(
          getFormattedProgress(getMsg("general-see-for-details",
              logFile.getPath())) +
          formatter.getLineBreak());
    }
  }

  /**
   * Writes an initial record in the installation's historical
   * log describing moving from one version to another.
   * @param fromVersion from with install will be migrated
   * @param toVersion to which install will be migrated
   * @return Long ID for this session
   * @throws ApplicationException if something goes wrong
   */
  protected Long writeInitialHistoricalRecord(
          BuildInformation fromVersion,
          BuildInformation toVersion)
          throws ApplicationException {
    Long id;
    try {
      HistoricalLog log =
              new HistoricalLog(getInstallation().getHistoryLogFile());
      id = log.append(fromVersion, toVersion,
              HistoricalRecord.Status.STARTED,
              "log file '" + QuickSetupLog.getLogFile().getPath() + "'");
    } catch (IOException e) {
      String msg = getMsg("error-logging-operation");
      throw ApplicationException.createFileSystemException(
              msg, e);
    }
    return id;
  }

  /**
   * Writes a record into this installation's historical log.
   * @param id obtained from calling <code>writeInitialHistoricalRecord</code>
   * @param from version from with install will be migrated
   * @param to version to which install will be migrated
   * @param status of the operation
   * @param note string with additional information
   * @throws ApplicationException if something goes wrong
   * @see {@link #writeInitialHistoricalRecord(BuildInformation,
          BuildInformation)}
   */
  protected void writeHistoricalRecord(
          Long id,
          BuildInformation from,
          BuildInformation to,
          HistoricalRecord.Status status,
          String note)
          throws ApplicationException {
    try {
      HistoricalLog log =
              new HistoricalLog(getInstallation().getHistoryLogFile());
      log.append(id, from, to, status, note);
    } catch (IOException e) {
      String msg = getMsg("error-logging-operation");
      throw ApplicationException.createFileSystemException(msg, e);
    }
  }

  /**
   * Returns a localized representation of a TopologyCacheException object.
   * @param e the exception we want to obtain the representation from.
   * @return a localized representation of a TopologyCacheException object.
   */
  protected String getStringRepresentation(TopologyCacheException e)
  {
    StringBuilder buf = new StringBuilder();

    String ldapUrl = e.getLdapUrl();
    if (ldapUrl != null)
    {
      String hostName = ldapUrl.substring(ldapUrl.indexOf("://") + 3);
      buf.append(getMsg("server-error", hostName) + " ");
    }
    if (e.getCause() instanceof NamingException)
    {
      buf.append(getThrowableMsg("bug-msg", null, e.getCause()));
    }
    else
    {
      // This is unexpected.
      buf.append(getThrowableMsg("bug-msg", null, e.getCause()));
    }
    return buf.toString();
  }

  /**
   * Gets an InitialLdapContext based on the information that appears on the
   * provided ServerDescriptor object.  Note that the server is assumed to be
   * registered and that contains a Map with ADSContext.ServerProperty keys.
   * @param server the object describing the server.
   * @param trustManager the trust manager to be used to establish the
   * connection.
   * @param dn the dn to be used to authenticate.
   * @param pwd the pwd to be used to authenticate.
   * @return the InitialLdapContext to the remote server.
   * @throws ApplicationException if something goes wrong.
   */
  protected InitialLdapContext getRemoteConnection(ServerDescriptor server,
      String dn, String pwd, ApplicationTrustManager trustManager)
  throws ApplicationException
  {
    Map<ADSContext.ServerProperty, Object> adsProperties =
      server.getAdsProperties();
    ServerLoader loader = new ServerLoader(adsProperties, dn, pwd,
        trustManager);

    InitialLdapContext ctx = null;
    try
    {
      ctx = loader.createContext();
    }
    catch (NamingException ne)
    {
      String errorMessage = getMsg("cannot-connect-to-remote-generic",
          server.getHostPort(true), ne.toString(true));
      throw new ApplicationException(
          ApplicationReturnCode.ReturnCode.CONFIGURATION_ERROR, errorMessage,
          ne);
    }
    return ctx;
  }

  /**
   * This class is used to notify the ProgressUpdateListeners of events
   * that are written to the standard error.  It is used in WebStartInstaller
   * and in OfflineInstaller.  These classes just create a ErrorPrintStream and
   * then they do a call to System.err with it.
   *
   * The class just reads what is written to the standard error, obtains an
   * formatted representation of it and then notifies the
   * ProgressUpdateListeners with the formatted messages.
   *
   */
  protected class ErrorPrintStream extends PrintStream {
    private boolean isFirstLine;

    /**
     * Default constructor.
     *
     */
    public ErrorPrintStream()
    {
      super(new ByteArrayOutputStream(), true);
      isFirstLine = true;
    }

    /**
     * {@inheritDoc}
     */
    public void println(String msg)
    {
      if (isFirstLine)
      {
        notifyListeners(getFormattedLogError(msg));
      } else
      {
        notifyListeners(formatter.getLineBreak() + getFormattedLogError(msg));
      }
      isFirstLine = false;
    }

    /**
     * {@inheritDoc}
     */
    public void write(byte[] b, int off, int len)
    {
      if (b == null)
      {
        throw new NullPointerException("b is null");
      }

      if (off + len > b.length)
      {
        throw new IndexOutOfBoundsException(
            "len + off are bigger than the length of the byte array");
      }
      println(new String(b, off, len));
    }
  }

  /**
   * This class is used to notify the ProgressUpdateListeners of events
   * that are written to the standard output. It is used in WebStartInstaller
   * and in OfflineInstaller. These classes just create a OutputPrintStream and
   * then they do a call to System.out with it.
   *
   * The class just reads what is written to the standard output, obtains an
   * formatted representation of it and then notifies the
   * ProgressUpdateListeners with the formatted messages.
   *
   */
  protected class OutputPrintStream extends PrintStream
  {
    private boolean isFirstLine;

    /**
     * Default constructor.
     *
     */
    public OutputPrintStream()
    {
      super(new ByteArrayOutputStream(), true);
      isFirstLine = true;
    }

    /**
     * {@inheritDoc}
     */
    public void println(String msg)
    {
      if (isFirstLine)
      {
        notifyListeners(getFormattedLog(msg));
      } else
      {
        notifyListeners(formatter.getLineBreak() + getFormattedLog(msg));
      }
      isFirstLine = false;
    }

    /**
     * {@inheritDoc}
     */
    public void write(byte[] b, int off, int len)
    {
      if (b == null)
      {
        throw new NullPointerException("b is null");
      }

      if (off + len > b.length)
      {
        throw new IndexOutOfBoundsException(
            "len + off are bigger than the length of the byte array");
      }

      println(new String(b, off, len));
    }
  }
}