/****************************************************************
 * This file is distributed under the following license:
 *
 * Copyright (c) 2008, defnax
 * Copyright (c) 2008, Matt Edman, Justin Hipple
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version 2
 *  of the License, or (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, 
 *  Boston, MA  02110-1301, USA.
 ****************************************************************/

/*
** \file helpbrowser.h
** \version $Id: helpbrowser.h 2362 2008-02-29 04:30:11Z edmanm $ 
** \brief Displays a list of help topics and content
*/

#ifndef _HELPBROWSER_H
#define _HELPBROWSER_H

#include <QMainWindow>
#include <QCloseEvent>
#include <QDomDocument>
#include <QDomElement>
#include <QDomNodeList>
#include <QTreeWidgetItem>
#include <QTextBrowser>
#include <QTextCursor>
#include <gui/common/rwindow.h>

#include "ui_helpbrowser.h"

class HelpBrowser : public RWindow
{
  Q_OBJECT

public:
  /** Default constructor **/
  HelpBrowser(QWidget *parent = 0);
 
public slots:
  /** Overrides the default QWidget::show() */
  void showWindow(QString topic = QString());
  
private slots:
  /** Called when the user clicks "Find Next" */
  void findNext();
  /** Called when the user clicks "Find Previous" */
  void findPrev();
  /** Called when the user starts a search */
  void search();
  /** Called when the user selects a different item in the contents tree */
  void contentsItemChanged(QTreeWidgetItem *current, QTreeWidgetItem *prev);
  /** Called when the user selects a different item in the search tree */
  void searchItemChanged(QTreeWidgetItem *current, QTreeWidgetItem *prev);
   
private:
  /** Returns the language in which help topics should appear, or English
   * ("en") if no translated help files exist for the current GUI language. */
  QString language();
  /** Load the contents of the help topics tree from the specified XML file. */
  void loadContentsFromXml(QString xmlFile);
  /** Load the contents of the help topics tree from the given DOM document. */
  bool loadContents(const QDomDocument *document, QString &errorString);
  /** Parse a Topic element and handle all its children. */
  void parseHelpTopic(const QDomElement &element, QTreeWidgetItem *parent);
  /** Returns true if the given Topic element has the necessary attributes. */
  bool isValidTopicElement(const QDomElement &topicElement);
  /** Builds a resource path to an html file associated with a help topic. */
  QString getResourcePath(const QDomElement &topicElement);
  /** Searches the current page for the phrase in the Find box */
  void find(bool forward);
  /** Creates a new item to be placed in the topic tree. */
  QTreeWidgetItem* createTopicTreeItem(const QDomElement &topicElement,
                                       QTreeWidgetItem *parent);
  /** Called when the user selects a different item in the tree. */
  void currentItemChanged(QTreeWidgetItem *current, QTreeWidgetItem *prev);
  /** Finds a topic in the topic tree. */
  QTreeWidgetItem* findTopicItem(QTreeWidgetItem *startItem, QString topic);
  /** Shows the help browser and finds a specific a topic in the browser. */
  void showTopic(QString topic);

  /** List of DOM elements representing topics. */
  QList<QDomElement> _elementList;
  /** Last phrase used for 'Find' */
  QString _lastFind;
  /** Last phrase searched on */
  QString _lastSearch;
  /** Indicates if phrase was previously found on current page */
  bool _foundBefore;

  /** Qt Designer generated QObject */
  Ui::HelpBrowser ui;
};

#endif