--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/QTfrontend/ui/widget/HistoryLineEdit.cpp	Wed Oct 19 16:10:18 2011 +0200
@@ -0,0 +1,153 @@
+/*
+ * 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 "SmartLineEdit.h"
+
+HistoryLineEdit::HistoryLineEdit(QWidget * parent, int maxHistorySize)
+: QLineEdit(parent)
+{
+    m_curHistEntryIdx = 0;
+    m_maxHistorySize = maxHistorySize;
+    m_history = new QStringList();
+}
+
+
+void HistoryLineEdit::rememberCurrentText()
+{
+    m_historyMutex.lock();
+
+    rememberCurrentTextUnsynced();
+
+    m_historyMutex.unlock();
+}
+
+
+void HistoryLineEdit::rememberCurrentTextUnsynced()
+{
+    QString newEntry = text();
+
+    // don't store whitespace-only/empty text
+    if (newEntry.trimmed().isEmpty())
+        return;
+
+    m_history->removeOne(newEntry); // no duplicates please
+    m_history->append(newEntry);
+
+    // do not keep more entries than allowed
+    if (m_history->size() > m_maxHistorySize)
+        m_history->removeFirst();
+
+    // we're looking at the latest entry
+    m_curHistEntryIdx = m_history->size() - 1;
+}
+
+
+void HistoryLineEdit::clear()
+{
+    m_historyMutex.lock();
+
+    QLineEdit::clear();
+    m_curHistEntryIdx = m_history->size();
+
+    m_historyMutex.unlock();
+}
+
+
+void HistoryLineEdit::reset()
+{
+    // forget history
+    m_historyMutex.lock();
+
+    m_history->clear();
+    m_curHistEntryIdx = 0;
+
+    m_historyMutex.unlock();
+}
+
+
+void HistoryLineEdit::navigateHistory(bool isGoingUp)
+{
+    m_historyMutex.lock();
+
+    // save possible changes to new entry
+    if ((m_curHistEntryIdx >= m_history->size() ||
+        (text() != m_history->at(m_curHistEntryIdx))))
+        {
+            rememberCurrentTextUnsynced();
+        }
+
+    if (isGoingUp)
+        m_curHistEntryIdx--;
+    else
+        m_curHistEntryIdx++;
+
+    // if Idx higher than valid range
+    if (m_curHistEntryIdx >= m_history->size())
+    {
+        QLineEdit::clear();
+        m_curHistEntryIdx = m_history->size();
+    }
+    // if Idx in valid range
+    else if (m_curHistEntryIdx >= 0)
+    {
+        setText(m_history->at(m_curHistEntryIdx));
+    }
+    // if Idx below 0
+    else
+        m_curHistEntryIdx = 0;
+
+
+    m_historyMutex.unlock();
+}
+
+
+void HistoryLineEdit::keyPressEvent(QKeyEvent * event)
+{
+    int key = event->key(); // retrieve pressed key
+
+    // navigate history with arrow keys
+    if (event->modifiers() == Qt::NoModifier)
+        switch (key)
+        {
+            case Qt::Key_Escape:
+                clear();
+                event->accept();
+                break;
+
+            case Qt::Key_Up:
+                navigateHistory(true);
+                event->accept();
+                break;
+
+            case Qt::Key_Down:
+                navigateHistory(false);
+                event->accept();
+                break;
+
+            default:
+                QLineEdit::keyPressEvent(event);
+                break;
+        }
+    // otherwise forward keys to parent
+    else
+        QLineEdit::keyPressEvent(event);
+}
+