Enhanced DataFilter Completion

.. now will repeat completion beyond the very
   first word on the line

.. needs to be enhanced to work when not at the
   end of the text (i.e. cursor move)

src/SearchBox.cpp

@@ -32,7 +32,7 @@
 #include <QDebug>
 
 SearchBox::SearchBox(Context *context, QWidget *parent, bool nochooser)
-    : QLineEdit(parent), context(context), parent(parent), filtered(false), nochooser(nochooser)
+    : QLineEdit(parent), context(context), parent(parent), filtered(false), nochooser(nochooser), active(false)
 {
     setFixedHeight(21);
     //clear button
@@ -69,7 +69,8 @@ SearchBox::SearchBox(Context *context, QWidget *parent, bool nochooser)
     connect(searchButton, SIGNAL(clicked()), this, SLOT(toggleMode()));
 
     // create an empty completer, configchanged will fix it
-    completer = new QCompleter(QStringList(), parent);
+    completer = new DataFilterCompleter(QStringList(), parent);
+    setCompleter(completer);
 
 #ifdef Q_OS_MAC
     setAttribute(Qt::WA_MacShowFocusRect, 0);
@@ -141,10 +142,6 @@ SearchBox::configChanged(qint32)
 
     }
 
-    // set the fields for the completer
-    setCompleter(NULL);
-    delete completer;
-
     // get suitably formated list
     QList<QString> list;
     QString last;
@@ -171,9 +168,34 @@ SearchBox::configChanged(qint32)
         list << name;
     }
 
-    // set new completer
-    completer = new QCompleter(list, parent);
-    if (mode == Filter) setCompleter(completer);
+    // set new list
+    completer->setList(list);
+}
+
+void
+SearchBox::updateCompleter(const QString &text)
+{
+    active = true;
+    if (mode == Filter && text.length()) {
+        QChar last = text[text.length()-1];
+
+        if (last.isLetterOrNumber()) {
+
+            // find out what end is
+            int i=text.length();
+            while (i && text[i-1].isLetterOrNumber()) i--;
+            QString prefix = text.mid(i, text.length()-i);
+
+            completer->update(prefix);
+
+            // get that popup ?
+            if (completer->completionCount()) {
+                completer->popup()->setCurrentIndex(completer->completionModel()->index(0, 0));
+            }
+        }
+
+    }
+    active=false;
 }
 
 void SearchBox::resizeEvent(QResizeEvent *)
@@ -209,7 +231,6 @@ void SearchBox::setMode(SearchBoxMode mode)
             searchButton->setIcon(filter);
             searchButton->setIconSize(QSize(11,11));
             setPlaceholderText(tr("Filter..."));
-            setCompleter(completer);
         }
         break;
 
@@ -220,7 +241,6 @@ void SearchBox::setMode(SearchBoxMode mode)
             searchButton->setIcon(search);
             searchButton->setIconSize(QSize(11,11));
             setPlaceholderText(tr("Search..."));
-            setCompleter(NULL);
         }
         break;
     }
@@ -378,3 +398,77 @@ SearchBox::addNamed()
         context->athlete->namedSearches->write();
     }
 }
+
+//
+// Working with the the autocompleter
+//
+void SearchBox::setCompleter(DataFilterCompleter *completer)
+{
+    if (this->completer) QObject::disconnect(this->completer, 0, this, 0);
+ 
+    this->completer = completer;
+ 
+    if (!this->completer) return;
+ 
+    this->completer->setWidget(this);
+    connect(completer, SIGNAL(activated(const QString&)), this, SLOT(insertCompletion(const QString&)));
+}
+ 
+void SearchBox::insertCompletion(const QString& completion)
+{
+    if (mode == Search) return;
+
+    QString t = text();
+
+    QChar last = t[t.length()-1];
+
+    if (last.isLetterOrNumber()) {
+
+        // find out what end is
+        int i=t.length();
+        while (i && t[i-1].isLetterOrNumber()) i--;
+        t.replace(i, t.length()-i, completion);
+
+        // now replace
+        setText(t);
+    }
+}
+ 
+ 
+void SearchBox::keyPressEvent(QKeyEvent *e)
+{
+    // only intercept in filter mode
+    if (mode == Search) return QLineEdit::keyPressEvent(e);
+
+    if (completer && completer->popup()->isVisible())
+    {
+        // The following keys are forwarded by the completer to the widget
+        switch (e->key())
+        {
+        case Qt::Key_Enter:
+        case Qt::Key_Return:
+        case Qt::Key_Escape:
+        case Qt::Key_Tab:
+        case Qt::Key_Backtab:
+            e->ignore();
+            return; // Let the completer do default behavior
+        }
+    }
+ 
+    bool isShortcut = (e->modifiers() & Qt::ControlModifier) && e->key() == Qt::Key_E;
+    if (!isShortcut)
+        QLineEdit::keyPressEvent(e); // Don't send the shortcut (CTRL-E) to the text edit.
+ 
+    if (!this->completer) return;
+ 
+    bool ctrlOrShift = e->modifiers() & (Qt::ControlModifier | Qt::ShiftModifier);
+    if (!isShortcut && !ctrlOrShift && e->modifiers() != Qt::NoModifier)
+    {
+        completer->popup()->hide();
+        return;
+    }
+
+    updateCompleter(text()); 
+    //completer->update(text());
+    //completer->popup()->setCurrentIndex(completer->completionModel()->index(0, 0));
+}