Foremost a fix for SmTreeModel

Not working again, but I eventually have to commit the changes. Fixes to
SmTreeModel:

* Fix SmTreeModel::index(). The previous comment was quite valid. I'm
surprised that it worked at all. I have no clue why to return an invalid
QModelIndex if the column isn't 0. Now an index with any valid column
number can be created.

* Fix SmTreeModel::parent(). Again, why shouldn't we create a parent
index with a column other than 0? No idea...

* Fix SmTreeModel::headerData(). Add some sanity checks.

* Fix SmTreeModel::findRecursive(). Well, what is there to say. It never
worked for models with a depth > 1, but obviously it didn't really
matter until now. To make it work I had to change SmTreeItem as well.
SmTreeItem::next() returns the next valid parent/sibling, or 0 if there
isn't one.

There may be some fallout from these changes, but they're yet to be
seen.

Changes to PictureView:
* fix selecting an item according to the new datasbase layout
* same goes for editing items. If an update actually works has to be
checked.

Overall, it's an intermediate commit that should have been a sane series
of commits. Can't be changed now...

1 files changed, 41 insertions, 33 deletions

diff --git a/smtreemodel.cpp b/smtreemodel.cpp
index 7df30d3..98fa4c8 100644
--- a/smtreemodel.cpp
+++ b/smtreemodel.cpp
@@ -9,6 +9,8 @@
 #include <QSettings>
 #include <QBrush>
 
+#include <QDebug>
+
 #include "smtreemodel.h"
 #include "smtreeitem.h"
 #include "smglobals.h"
@@ -40,16 +42,20 @@ int SmTreeModel::columnCount(const QModelIndex &parent) const{
 }
 
 QModelIndex SmTreeModel::index(int row, int column, const QModelIndex &parent) const{
-    //this is totally bogus! Why? Tentatively leaving it in for now...
-    if(parent.isValid() && (parent.column() != 0)){
-		return QModelIndex();
+    // return child from root if parent is invalid
+    // this was difficult to figure this out!
+    if(!parent.isValid()){
+        return createIndex(row, column, mRootItem->child(row));
     }
-	SmTreeItem *parentItem = itemAt(parent);
-	SmTreeItem *childItem = parentItem->child(row);
-	if(childItem){
-		return createIndex(row, column, childItem);
-	}
-	return QModelIndex();
+    SmTreeItem *parentItem = static_cast<SmTreeItem*>(parent.internalPointer());
+    if( (parentItem == 0) ||
+        (row < 0) ||
+        (column < 0) ||
+        (row >= parentItem->childCount()) ||
+        (column > parentItem->columnCount())){
+            return QModelIndex();
+    }
+    return createIndex(row, column, parentItem->child(row));
 }
 
 QModelIndex SmTreeModel::parent(const QModelIndex &child) const{
@@ -57,13 +63,13 @@ QModelIndex SmTreeModel::parent(const QModelIndex &child) const{
 		return QModelIndex();
 	}
 
-	SmTreeItem *childItem = itemAt(child);
+    SmTreeItem *childItem = static_cast<SmTreeItem*>(child.internalPointer());
 	SmTreeItem *parentItem = childItem->parent();
 
-	if(parentItem == mRootItem){
+    if(parentItem == 0){
 		return QModelIndex();
 	}
-	return createIndex(parentItem->row(), 0, parentItem);
+    return createIndex(parentItem->row(), child.column(), parentItem);
 }
 
 Qt::ItemFlags SmTreeModel::flags(const QModelIndex &index) const{
@@ -74,7 +80,7 @@ Qt::ItemFlags SmTreeModel::flags(const QModelIndex &index) const{
 }
 
 QVariant SmTreeModel::headerData(int section, Qt::Orientation orientation, int role) const{
-	if((orientation == Qt::Horizontal) && (role == Qt::DisplayRole)){
+    if((orientation == Qt::Horizontal) && (role == Qt::DisplayRole) && (section > -1) && (section < mHeaders.count())){
 		return mHeaders.at(section);
 	}
 	return QVariant();
@@ -142,30 +148,28 @@ QModelIndex SmTreeModel::find(const QVariant &value, int column, const QModelInd
 	return QModelIndex();
 }
 
-QModelIndex SmTreeModel::findRecursive(const QVariant &value, int column, const QModelIndex &parent) const{
-	SmTreeItem *parentItem = 0;
-	if(!parent.isValid()){
-		parentItem = mRootItem;
-	}else{
-		parentItem = static_cast<SmTreeItem*>(parent.internalPointer());
-	}
-    if(parentItem->data(column) == value){
-        return parent;
+QModelIndex SmTreeModel::findRecursive(const QVariant &value, int column, const QModelIndex &start) const{
+    if(!start.isValid()){
+        return QModelIndex();
     }
-	for(int i = 0; i < parentItem->childCount(); ++i){
-		SmTreeItem *child = parentItem->child(i);
+    SmTreeItem *startItem = static_cast<SmTreeItem*>(start.internalPointer());
+    if(startItem->data(column) == value){
+        return start;
+    }
+    for(int i = 0; i < startItem->childCount(); ++i){
+        SmTreeItem *child = startItem->child(i);
         if(child->data(column) == value){
             return createIndex(i, column, child);
         }
-		if(child->childCount()){
-			return findRecursive(value, column, createIndex(i, column, child));
-		}
-	}
-    QModelIndex next = index(parent.row() + 1, column, parent.parent());
-	if(!next.isValid()){
-		return QModelIndex();
-	}
-	return findRecursive(value, column, next);
+        if(child->childCount()){
+            return findRecursive(value, column, createIndex(i, column, child));
+        }
+    }
+    SmTreeItem *next = startItem->next();
+    if(next){
+        return findRecursive(value, column, createIndex(next->row(), column,  next));
+    }
+    return QModelIndex();
 }
 
 bool SmTreeModel::setRoot(SmTreeItem *rootItem){
@@ -179,6 +183,10 @@ bool SmTreeModel::setRoot(SmTreeItem *rootItem){
 	return false;
 }
 
+QModelIndex SmTreeModel::rootIndex() const {
+    return createIndex(0, 0, mRootItem);
+}
+
 SmTreeItem *SmTreeModel::parentItem(const QModelIndex &child) const{
 	QModelIndex parent = child.parent();
 	if(parent == QModelIndex()){