Natural sorting fix: assure that directories are sorted always before files as Ellen has recommended. One minor issue is left: when the sort order is descending, the natural sorting result is:

 item 10.jpg
 item 11.jpg
 item 2.jpg
 item 1.jpg
instead of
 item 11.jpg
 item 10.jpg
 item 2.jpg
 item 1.jpg

svn path=/trunk/playground/utils/dolphin/; revision=622751

2 files changed, 49 insertions, 30 deletions

diff --git a/src/dolphinsortfilterproxymodel.cpp b/src/dolphinsortfilterproxymodel.cpp
index e983007c1..34f7edc21 100644
--- a/src/dolphinsortfilterproxymodel.cpp
+++ b/src/dolphinsortfilterproxymodel.cpp
@@ -62,6 +62,12 @@ void DolphinSortFilterProxyModel::setSorting(DolphinView::Sorting sorting)
          m_sortOrder );
 }
 
+void DolphinSortFilterProxyModel::setSortOrder(Qt::SortOrder sortOrder)
+{
+    // change the sort order by keeping the current column
+    sort(dolphinViewToDirModelColumn[m_sorting], sortOrder);
+}
+
 void DolphinSortFilterProxyModel::sort(int column, Qt::SortOrder sortOrder)
 {
     m_sortOrder = sortOrder;
@@ -71,13 +77,41 @@ void DolphinSortFilterProxyModel::sort(int column, Qt::SortOrder sortOrder)
     QSortFilterProxyModel::sort(column,sortOrder);
 }
 
-void DolphinSortFilterProxyModel::setSortOrder(Qt::SortOrder sortOrder)
+bool DolphinSortFilterProxyModel::lessThan(const QModelIndex& left,
+                                           const QModelIndex& right) const
 {
-    // change the sort order by keeping the current column
-    sort(dolphinViewToDirModelColumn[m_sorting], sortOrder);
+    KDirModel* dirModel = static_cast<KDirModel*>(sourceModel());
+
+    QVariant leftData  = dirModel->data(left,  sortRole());
+    QVariant rightData = dirModel->data(right, sortRole());
+
+    if ((leftData.type() == QVariant::String) && (rightData.type() == QVariant::String)) {
+        const QString leftStr  = leftData.toString();
+        const QString rightStr = rightData.toString();
+
+        const bool leftIsDir  = dirModel->itemForIndex(left)->isDir();
+        const bool rightIsDir = dirModel->itemForIndex(right)->isDir();
+
+        // assure that directories are always sorted before files
+        if (leftIsDir && !rightIsDir) {
+            return true;
+        }
+
+        if (!leftIsDir && rightIsDir) {
+            return false;
+        }
+
+        return sortCaseSensitivity() ? (naturalCompare(leftStr, rightStr) < 0) :
+                                       (naturalCompare(leftStr.toLower(), rightStr.toLower()) < 0);
+    }
+
+    // We have set a SortRole and trust the ProxyModel to do
+    // the right thing for now.
+    return QSortFilterProxyModel::lessThan(left, right);
 }
 
-static int naturalCompare(const QString& a, const QString& b)
+int DolphinSortFilterProxyModel::naturalCompare(const QString& a,
+                                                const QString& b) const
 {
     // This method chops the input a and b into pieces of
     // digits and non-digits (a1.05 becomes a | 1 | . | 05)
@@ -124,7 +158,7 @@ static int naturalCompare(const QString& a, const QString& b)
         if ((*currA == '0') || (*currB == '0')) {
             // one digit-sequence starts with 0 -> assume we are in a fraction part
             // do left aligned comparison (numbers are considered left aligend)
-            while ( 1 ) {
+            while (1) {
                 if (!currA->isDigit() && !currB->isDigit()) {
                     break;
                 }
@@ -190,25 +224,4 @@ static int naturalCompare(const QString& a, const QString& b)
     return currA->isNull() ? -1 : +1;
 }
 
-
-bool DolphinSortFilterProxyModel::lessThan(const QModelIndex& left,
-                                           const QModelIndex& right) const
-{
-
-    QVariant leftData = sourceModel()->data(left, sortRole());
-    QVariant rightData = sourceModel()->data(right, sortRole());
-
-    if (leftData.type() == QVariant::String && rightData.type() == QVariant::String) {
-        const QString left = leftData.toString();
-        const QString right = rightData.toString();
-
-        return sortCaseSensitivity() ? (naturalCompare(left, right) < 0) :
-                                       (naturalCompare(left.toLower(), right.toLower()) < 0);
-    }
-
-    // We have set a SortRole and trust the ProxyModel to do
-    // the right thing for now.
-    return QSortFilterProxyModel::lessThan(left,right);
-}
-
 #include "dolphinsortfilterproxymodel.moc"
diff --git a/src/dolphinsortfilterproxymodel.h b/src/dolphinsortfilterproxymodel.h
index 0ca1db535..23cd45134 100644
--- a/src/dolphinsortfilterproxymodel.h
+++ b/src/dolphinsortfilterproxymodel.h
@@ -35,6 +35,8 @@
  * - item_1.png
  * - item_2.png
  * - item_10.png
+ *
+ * It is assured that directories are always sorted before files.
  */
 class DolphinSortFilterProxyModel : public QSortFilterProxyModel
 {
@@ -47,22 +49,26 @@ public:
     void setSorting(DolphinView::Sorting sorting);
     DolphinView::Sorting sorting() const { return m_sorting; }
 
+    void setSortOrder(Qt::SortOrder sortOrder);
+    Qt::SortOrder sortOrder() const { return m_sortOrder; }
+
     /**
      * @reimplemented, @internal
      *
      * If the view 'forces' sorting order to change we will
      * notice now.
      */
-    virtual void sort (int column,
-                       Qt::SortOrder order = Qt::AscendingOrder);
-    void setSortOrder(Qt::SortOrder sortOrder);
-    Qt::SortOrder sortOrder() const { return m_sortOrder; }
+    virtual void sort(int column,
+                      Qt::SortOrder order = Qt::AscendingOrder);
 
 protected:
     virtual bool lessThan(const QModelIndex& left,
                           const QModelIndex& right) const;
 
 private:
+    int naturalCompare(const QString& a, const QString& b) const;
+
+private:
     DolphinView::Sorting m_sorting;
     Qt::SortOrder m_sortOrder;
 };