/*

 * 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

 */

#include <QStringList>

#include <QEvent>

#include <QRegExp>

#include "HistoryLineEdit.h"

/**

 * A {@link HistoryLineEdit} that additionally features:

 * + Auto-completion for word under cursor when the TAB key is pressed.

 * + ESC key clears text.

 *

 * Note:

 *   * A Keyword can either be a command (if first word) or

 *     a nickname (completed regardless of position in text).

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

 * @author sheepluva

 * @since 0.9.17

 */

class SmartLineEdit : public HistoryLineEdit

{

 Q_OBJECT

public:

    /**

    * Class constructor.

    * @param parent parent QWidget.

    * @param maxHistorySize maximum amount of history entries kept.

    */

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

    /**

     * Adds commands to the auto-completion feature.

     * @param commands list of commands to be added.

     */

    void addCommands(const QStringList & commands);

    /**

     * Adds a single nickname to the auto-completion feature.

     * @param nickname name to be added.

     */

    void addNickname(const QString & nickname);

    /**

     * Removes commands from the auto-completion feature.

     * @param commands list of commands to be removed.

     */

    void removeCommands(const QStringList & commands);

    /**

     * Removes a single nickname from the auto-completion feature.

     * @param nickname name to be removed.

     */

    void removeNickname(const QString & nickname);

    /**

     * Forget all keywords and input history.

     */

    void reset();

protected:

    /**

     * Overrides method of parent class.

     * Forward pressed TAB to parent class' method (for focus handling etc)

     * only if line is empty.

     * @param event the key event.

     * @return returns true if the event was recognized.

     */

    virtual bool event(QEvent * event);

    /**

     * Overrides method of parent class.

     * Autocompletes if TAB is reported as pressed key in the key event,

     * ESC leads to the contents being cleared.

     * otherwise keys are forwarded to parent method.

     * @param event the key event.

     */

    virtual void keyPressEvent(QKeyEvent * event);

private:

    QRegExp m_whitespace; // regexp that matches a whitespace

    QStringList * m_cmds;  // list of recognized commands

    QStringList * m_nicks; // list of recognized nicknames

    // these variables contain information about the last replacement

    // they get reset whenever cursor is moved or text is changed

    QString m_beforeMatch; // the string that was just matched

    bool m_hasJustMatched; // whether this widget just did an auto-completion

    QString m_prefix; // prefix of the text replacement this widget just did

    QString m_postfix; // postfix of the text replacement this widget just did

    QMutex m_keywordMutex; // make keyword QStringList action thread-safe

    /**

     * Autocompletes the contents based on the known commands and/or names.

     */

    void autoComplete();

private slots:

    /**

     * Resets the information about the last match and text replacement.

     */

    void resetAutoCompletionStatus();

};