/*

 * Hedgewars, a free turn based strategy game

 * Copyright (c) 2006-2007 Igor Ulyanov <iulyanov@gmail.com>

 * Copyright (c) 2007-2011 Andrey Korotaev <unC0Rr@gmail.com>

 *

 * 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; version 2 of the License

 *

 * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA

 */

#ifndef HEDGEWARS_HISTORYLINEEDIT

#define HEDGEWARS_HISTORYLINEEDIT

#include <QLineEdit>

#include <QString>

#include <QKeyEvent>

#include <QMutex>

class QLineEdit;

/**

 * A modification of QLineEdit that features:

 * + History of previous contents, re-selectable using the arrow keys.

 *

 * Note:

 *   * Public methods for accessing history are thread-safe.

 * @author sheepluva

 * @since 0.9.17

 */

class HistoryLineEdit : public QLineEdit

{

 Q_OBJECT

public:

    /**

    * Class constructor.

    * @param parent parent QWidget.

    * @param maxHistorySize maximum amount of history entries kept.

    */

    HistoryLineEdit(QWidget * parent = 0, int maxHistorySize = 64);

    /**

     * Appends current text to history (if not only whitespaces);

     */

    void rememberCurrentText();

    /**

     * Forget all history.

     */

    void reset();

public slots:

    /**

     * Clears the contents.

     */

    void clear();

protected:

    /**

     * Overrides method of parent class.

     * Arrow keys are used for navigating the history.

     * All other keys are forwarded to the parent's method.

     * @param event the key event.

     */

    virtual void keyPressEvent(QKeyEvent * event);

private:

    int m_maxHistorySize; // the maximum allowed size for the history

    int m_curHistEntryIdx; // the index of the displayed used entry

    QStringList * m_history; // history of previous inputs

    QMutex m_historyMutex; // make history QStringList action thread-safe

    /**

     * Navigates content history in the desired direction.

     * Note: no wrap-around on purpose (so that holding down/up will get the

     * the user to the respective end rather than into an endless cycle :P)

     * @param isGoingUp true: next older entry, false: next more recent entry.

     */

    void navigateHistory(bool isGoingUp);

    /**

     * Appends current text to history, without Mutex.

     */

    void rememberCurrentTextUnsynced();

};

#endif // HEDGEWARS_HISTORYLINEEDIT