/*
        Copyright 2006-2020 QElectroTech Team
        This file is part of QElectroTech.

        QElectroTech is free software: you can redistribute it and/or modify
        it under the terms of the GNU General Public License as published by
        the Free Software Foundation, either version 2 of the License, or
        (at your option) any later version.

        QElectroTech is distributed in the hope that it will be useful,
        but WITHOUT ANY WARRANTY; without even the implied warranty of
        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
        GNU General Public License for more details.

        You should have received a copy of the GNU General Public License
        along with QElectroTech.  If not, see <http://www.gnu.org/licenses/>.
*/
#include "nomenclaturemodel.h"
#include "qetapp.h"
#include "qetproject.h"
#include "qetxml.h"

#include <QModelIndex>
#include <QFont>

/**
 * @brief NomenclatureModel::NomenclatureModel
 * @param project :project of this nomenclature
 * @param parent : parent QObject
 */
NomenclatureModel::NomenclatureModel(QETProject *project, QObject *parent) :
	QAbstractTableModel(parent),
	m_project(project)
{
	connect(m_project->dataBase(), &projectDataBase::dataBaseUpdated, this, &NomenclatureModel::dataBaseUpdated);
}

/**
 * @brief NomenclatureModel::rowCount
 * Reimplemented for QAbstractTableModel
 * @param parent
 * @return
 */
int NomenclatureModel::rowCount(const QModelIndex &parent) const
{
    if (parent.isValid())
        return 0;

	return  m_record.count();
}

/**
 * @brief NomenclatureModel::columnCount
 * Reimplemented for QAbstractTableModel
 * @param parent
 * @return
 */
int NomenclatureModel::columnCount(const QModelIndex &parent) const
{
    if (parent.isValid())
        return 0;

	if (m_record.count()) {
		return m_record.first().count();
	}

	return 0;
}

/**
 * @brief NomenclatureModel::setHeaderData
 * Reimplemented from QAbstractTableModel.
 * Only horizontal orientation is accepted.
 * @param section
 * @param orientation
 * @param value
 * @param role
 * @return
 */
bool NomenclatureModel::setHeaderData(int section, Qt::Orientation orientation, const QVariant &value, int role)
{
	if (orientation == Qt::Vertical) {
		return false;
	}
	auto hash_ = m_header_data.value(section);
	hash_.insert(role, value);
	m_header_data.insert(section, hash_);
	headerDataChanged(orientation, section, section);
	return true;
}

/**
 * @brief NomenclatureModel::headerData
 * Reimplemented from QAbstractTableModel.
 * @param section
 * @param orientation
 * @param role
 * @return
 */
QVariant NomenclatureModel::headerData(int section, Qt::Orientation orientation, int role) const
{
	if (orientation == Qt::Vertical) {
		return QVariant();
	}

	if (m_header_data.contains(section))
	{
		auto hash_ = m_header_data.value(section);
		if (role == Qt::DisplayRole && !hash_.contains(Qt::DisplayRole)) { //special case to have the same behavior as Qt
			return hash_.value(Qt::EditRole);
		}
		return m_header_data.value(section).value(role);
	}
	return QVariant();
}

/**
 * @brief NomenclatureModel::setData
 * Only store the data for the index 0.0
 * @param index
 * @param value
 * @param role
 * @return
 */
bool NomenclatureModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
	if (!index.isValid() || index.row() != 0 || index.column() != 0) {
		return false;
	}
	m_index_0_0_data.insert(role, value);
	emit dataChanged(index, index, QVector<int>(role));
	return true;
}

/**
 * @brief NomenclatureModel::data
 * Reimplemented for QAbstractTableModel
 * @param index
 * @param role
 * @return
 */
QVariant NomenclatureModel::data(const QModelIndex &index, int role) const
{
    if (!index.isValid())
        return QVariant();

	if (index.row() == 0 &&
		index.column() == 0 &&
		role != Qt::DisplayRole) {
		return m_index_0_0_data.value(role);
	}

	if (role == Qt::DisplayRole) {
		QVariant v(m_record.at(index.row()).at(index.column()));
		return v;
	}

	return QVariant();
}

/**
 * @brief NomenclatureModel::query
 * Query the internall bd with @query.
 * @param query
 */
void NomenclatureModel::query(const QString &query)
{
	auto rm_ = m_query != query;
	if (rm_) {
		emit beginResetModel();
	}

	m_query = query;

	if (m_project)
	{
		if (rm_) {
			disconnect(m_project->dataBase(), &projectDataBase::dataBaseUpdated, this, &NomenclatureModel::dataBaseUpdated);
		}
		m_project->dataBase()->updateDB();
		if (rm_) {
			m_record = m_project->dataBase()->elementsInfoFromQuery(m_query);
			connect(m_project->dataBase(), &projectDataBase::dataBaseUpdated, this, &NomenclatureModel::dataBaseUpdated);
		}
	}

	if (rm_) { emit endResetModel();}
}

QETProject *NomenclatureModel::project() const {
	return m_project.data();
}

/**
 * @brief NomenclatureModel::autoHeaders
 * Try to determine the name of each columns header
 */
void NomenclatureModel::autoHeaders()
{
	auto headers = projectDataBase::headersFromElementsInfoQuery(m_query);
	for (auto i=0 ; i<headers.size() ; ++i) {
		this->setHeaderData(i, Qt::Horizontal, headers.at(i));
	}
}

/**
 * @brief NomenclatureModel::toXml
 * Save the model to xml,since model can have unlimited data we only save few data.
 * The query and all header data. All other data are not saved.
 * @param document
 * @return
 */
QDomElement NomenclatureModel::toXml(QDomDocument &document) const
{
	auto dom_element = document.createElement(xmlTagName());

		//query
	auto dom_query = document.createElement("query");
	auto dom_query_txt = document.createTextNode(m_query);
	dom_query.appendChild(dom_query_txt);
	dom_element.appendChild(dom_query);

		//header data
	QHash<int, QList<int>> horizontal_;
	for (auto key : m_header_data.keys()) {
		horizontal_.insert(key, m_header_data.value(key).keys()); }

	dom_element.appendChild(QETXML::modelHeaderDataToXml(document, this, horizontal_, QHash<int, QList<int>>()));

	return dom_element;
}

/**
 * @brief NomenclatureModel::fromXml
 * Restore the model from xml
 * @param element
 */
void NomenclatureModel::fromXml(const QDomElement &element)
{
	if (element.tagName() != xmlTagName())
		return;

	query(element.firstChildElement("query").text());
	QETXML::modelHeaderDataFromXml(element.firstChildElement("header_data"), this);
}

/**
 * @brief NomenclatureModel::dataBaseUpdated
 * slot called when the project database is updated
 */
void NomenclatureModel::dataBaseUpdated()
{
	auto new_record = m_project->dataBase()->elementsInfoFromQuery(m_query);

		//This a very special case, if this nomenclature model is added
		//befor any element, column count return 0, so in this case we emit column inserted
	if (new_record.size() != m_record.size())
	{
		emit beginResetModel();
		m_record = new_record;
		emit endResetModel();
	}
	else
	{
		m_record = new_record;
		auto row = m_record.size();
		auto col = row ? m_record.first().count() : 1;

		emit dataChanged(this->index(0,0), this->index(row-1, col-1), QVector<int>(Qt::DisplayRole));
	}
}