#include <QtGui>

#include <iostream>

using namespace std;

#include "treeitem.h"

#include "treemodel.h"

TreeModel::TreeModel(QObject *parent)

    : QAbstractItemModel(parent)

{

    QList<QVariant> rootData;

    rootData << "Heading" << "Type" <<"Note";

    rootItem = new TreeItem(rootData);

}

TreeModel::~TreeModel()

{

    delete rootItem;

}

QVariant TreeModel::data(const QModelIndex &index, int role) const

{

    if (!index.isValid())

        return QVariant();

    if (role != Qt::DisplayRole)

        return QVariant();

    TreeItem *item = getItem (index);

    return item->data(index.column());

}

Qt::ItemFlags TreeModel::flags(const QModelIndex &index) const

{

    if (!index.isValid())

        return Qt::ItemIsEnabled;

    return Qt::ItemIsEnabled | Qt::ItemIsSelectable;

}

QVariant TreeModel::headerData(int section, Qt::Orientation orientation,

                               int role) const

{

    if (orientation == Qt::Horizontal && role == Qt::DisplayRole)

        return rootItem->data(section);

    return QVariant();

}

QModelIndex TreeModel::index(int row, int column, const QModelIndex &parent)

            const

{

    TreeItem *parentItem;

    if (!parent.isValid())

        parentItem = rootItem;

    else

        parentItem = getItem (parent);

    TreeItem *childItem = parentItem->child(row);

    if (childItem)

        return createIndex(row, column, childItem);

    else

        return QModelIndex();

}

QModelIndex TreeModel::parent(const QModelIndex &index) const

{

    if (!index.isValid())

        return QModelIndex();

    TreeItem *ti= getItem (index);

    TreeItem *parentItem = ti->parent();

	//cout << "TreeModel::parent  ti="<<ti<<" "<<ti->getHeading().toStdString()<<"  pi="<<parentItem<<"  "<<endl;

    if (parentItem == rootItem)

        return QModelIndex();

	if (!parentItem)

	{

		cout <<"TreeModel::parent      ti=="<<ti<<"  "<<ti->getHeading().toStdString()<<endl;

        return QModelIndex();	// FIXME-3 do this to avoid segfault, but why?

		                        // see also my question on qt-interest in march

	}	

    return createIndex(parentItem->childNumber(), 0, parentItem);

}

int TreeModel::rowCount(const QModelIndex &parent) const

{

    TreeItem *parentItem;

    if (!parent.isValid())

        parentItem = rootItem;

    else

        parentItem = getItem (parent);

    return parentItem->childCount();

}

int TreeModel::columnCount(const QModelIndex &parent) const

{

    if (parent.isValid())

        return getItem (parent)->columnCount();

    else

        return rootItem->columnCount();

}

TreeItem* TreeModel::next(TreeItem* &current, TreeItem* &previous, int &d0)

{

	// Walk through map beginning at current with previous==0

	// Start at root, if current==NULL

	if (!current) current=rootItem;

	// Are we just beginning to walk the map?

	if (!previous)

	{

		previous=current;

		d0=current->depth();

		current=current->getFirstBranch();

		return current;

	}

	//std::cout << " cur="<<current->getHeading().toStdString();

	//std::cout << " prev="<<previous->getHeading().toStdString()<<std::endl;

	// Going up or down (deeper)?

	if (current->depth() > previous->depth() )

	{	

		// Coming from above

		// Trying  to go down deeper

		if (current->branchCount() >0 )

		{

			previous=current;

			current=current->getFirstBranch();

			return current;

		}	

		// turn around and go up again

	}	

	// Coming from below,

	// Trying to go down again to siblings

	TreeItem *sibling=current->getBranchNum (previous->num()+1);

	if (sibling)

	{	

		// Found sibling of previous, go there

		previous=current;

		current=sibling;

		return current;

	} 

	// Go up and try to find siblings of current

	previous=current;

	current=current->parent();

	// Check if we still can go somewhere

	if (!current) return current;

	while (current && current->depth() < previous->depth() )

		next (current,previous,d0);

	return current;

}

bool TreeModel::insertRows ( int row, int count, const QModelIndex & parent)

{

	std::cout << "TreeModel insertRows()\n";

	int last=row+count-1;

	beginInsertRows (parent,row,last);

	for (int i=row; i<=last; i++)

	{

		std::cout << "TreeModel::insertRows inserting i="<<i<<std::endl;

	}

	endInsertRows ();

	return true;

}

bool TreeModel::removeRows ( int row, int count, const QModelIndex & parent)

{

	int last=row+count-1;

	cout << "TreeModel::removeRows row="<<row<<"  count="<<count<<"  last="<<last<<endl;

    TreeItem *pi= getItem (parent);

	cout << "  pi="<<pi<<"  "<<pi->getHeading().toStdString()<<endl;

	beginRemoveRows (parent,row,last);

	for (int i=row; i<=last; i++)

	{

		cout << "TreeModel::removeRows removing i="<<i<<std::endl;

		pi->removeChild (row);

	}

	endRemoveRows ();

	return true;

}

TreeItem *TreeModel::getItem(const QModelIndex &index) const

{

    if (index.isValid()) {

		TreeItem *item = static_cast<TreeItem*>(index.internalPointer());

        if (item) return item;

    }

    return rootItem;

}

QModelIndex TreeModel::index (TreeItem* ti)

{

	return createIndex (ti->row(),ti->column(),ti);

}