#include "TreeModel.h"

TreeModel::TreeModel(QObject * parent) :
    QAbstractItemModel(parent) ,
    _columnCount(1) ,
    _horizontalHeader(QList<QString>()<<QString::fromLocal8Bit("")) ,
    _root()
{
}

TreeModel::TreeModel(unsigned columns , QObject * parent) :
    QAbstractItemModel(parent) ,
    _columnCount(columns) ,
    _root()
{
}

TreeModel::Item * TreeModel::get_item(const QModelIndex & index)
{
    return reinterpret_cast<Item *>(index.internalPointer());
}

const TreeModel::Item * TreeModel::get_item(const QModelIndex & index) const
{
    return const_cast<TreeModel *>(this)->get_item(index);
}

QModelIndex TreeModel::index(int row , int column , const QModelIndex & parent) const
{
    const Item * item = get_item(parent);
    if (!item)
    {
        item = &_root;
    }

    return createIndex(row , column , const_cast<Item *>(item->child(row)));
}

QModelIndex TreeModel::parent(const QModelIndex & index) const
{
    const Item * item = get_item(index);
    if (item)
    {
        const Item * parent = item->parent();
        if (parent)
        {
            const Item * grand_parent = parent->parent();
            int row = 0;
            if (grand_parent)
            {
                row = grand_parent->childRow(parent);
            }
            return createIndex(row , 0 , const_cast<Item *>(parent));
        }
    }
    return QModelIndex();
}

int TreeModel::rowCount(const QModelIndex & parent) const
{
    const Item * item = get_item(parent);
    if (!item)
    {
        item = &_root;
    }
    return item->childrenCount();
}

int TreeModel::columnCount(const QModelIndex & parent) const
{
    return _columnCount;
}

QVariant TreeModel::data(const QModelIndex & index , int role) const
{
    const Item * item = get_item(index);
    if (item)
    {
        return item->data(role);
    }

    //not found
    return QVariant();
}

QVariant TreeModel::headerData(int section , Qt::Orientation orientation , int role) const
{
    if (orientation==Qt::Horizontal && role==Qt::DisplayRole && section<_horizontalHeader.size())
    {
        return _horizontalHeader.at(section);
    }
    return QVariant();
}

bool TreeModel::setData(const QModelIndex & index , const QVariant & value,  int role)
{
    Item * item = get_item(index);
    if (item)
    {
        item->setData(value , role);
        return true;
    }

    //error
    return false;
}

bool TreeModel::insertRow(int row , const QModelIndex & parent)
{
    Item * item = get_item(parent);
    if (!item)
    {
        item = &_root;
    }

    beginInsertRows(parent , row  ,row);
    bool rv = item->insertRow(row);
    endInsertRows();

    return rv;
}

void TreeModel::clear(void)
{
    //removeRows(0  rowCount());
    beginResetModel();
    _root.clear();
    endResetModel();
}


unsigned TreeModel::Item::next_id = 0;

TreeModel::Item::Item() : _id(next_id++) , _parent(NULL),  _data(),  _children()
{
}

void TreeModel::Item::clear(void)
{
    _children.clear();
    _data.clear();
}

bool TreeModel::Item::insertRow(int row)
{
    if (row>=0 && row<=_children.size())
    {
        _children.insert(row , Item());
        _children[row].setParent(this);
        return true;
    }
    return false;
}

void TreeModel::Item::setData(const QVariant & value,  int role)
{
    _data.insert(role , value);
}

QVariant TreeModel::Item::data(int role) const
{
    QMap<int , QVariant>::const_iterator iter = _data.constFind(role);
    if (iter!=_data.constEnd())
    {
        return *iter;
    }
    return QVariant();
}

int TreeModel::Item::childrenCount(void) const
{
    return _children.size();
}

TreeModel::Item * TreeModel::Item::child(int index)
{
    if (index>=0 && index<_children.size())
    {
        return &(_children[index]);
    }
    return NULL;
}

const TreeModel::Item * TreeModel::Item::child(int index) const
{
    return const_cast<TreeModel::Item *>(this)->child(index);
}

int TreeModel::Item::childRow(const TreeModel::Item * child) const
{
    if (!child)
    {
        return -1;
    }
    int index = 0;
    foreach(const TreeModel::Item & item,  _children)
    {
        if (item.id()==child->id())
        {
            return index;
        }
        index++;
    }
    return -1;
}