#include "CrudModel.h"
#include "ASyncWindow.h"
#include "OpenDatabase.h"
#include "PgDatabaseCatalog.h"
#include "PgAttributeContainer.h"
#include "PgConstraintContainer.h"
#include "GlobalIoService.h"
#include "SqlFormattingUtils.h"
#include "WorkManager.h"
#include <QtConcurrent>
#include <QFuture>
#include <QFutureWatcher>
#include "Pgsql_oids.h"

#include <string>

CrudModel::CrudModel(ASyncWindow *async_window)
	: m_asyncWindow(async_window)
	, m_dbConn(*getGlobalAsioIoService())
{
	connect(&m_dbConn, &ASyncDBConnection::onStateChanged, this, &CrudModel::connectionStateChanged);
}

CrudModel::~CrudModel()
{
	m_dbConn.closeConnection();
}


/*
 * Strategy
 * when ordered by primary key, offset and limit work very quickly so we can get away with not loading
 * everything.
 */
void CrudModel::setConfig(std::shared_ptr<OpenDatabase> db, const PgClass &table)
{
	m_database = db;
	m_table = table;
	m_primaryKey = db->catalogue()->constraints()->getPrimaryForRelation(table.oid);
	//cat->attributes()->getColumnsForRelation()
	callLoadData = true;
	m_dbConn.setupConnection(m_database->config());
}

QVariant CrudModel::headerData(int section, Qt::Orientation orientation, int role) const
{
	QVariant r;
	if (role == Qt::DisplayRole) {
		if (orientation == Qt::Horizontal) {
			QString s(m_roData->getColName(section));
			s += "\n";
			s += getTypeDisplayString(*m_database->catalogue(), getType(section));
			r = s;
		}
		else {
			r = QString::number(section + 1);
		}
	}
	return r;
}


// Basic functionality:
int CrudModel::rowCount(const QModelIndex &parent) const
{

	return m_roData ? m_roData->rows() : 0;
}

int CrudModel::columnCount(const QModelIndex &parent) const
{
	return m_roData ? m_roData->cols() : 0;
}

Oid CrudModel::getType(int column) const
{
	return m_roData ? m_roData->type(column) : InvalidOid;
}

QVariant CrudModel::getData(const QModelIndex &index) const
{
	QVariant r;
	if (m_roData) {
		int rij = index.row();
		int col = index.column();
		if (m_roData->null(col, rij)) {
			r = "null";
		}
		else {
			Oid o = m_roData->type(col);
			auto value = m_roData->get(col, rij);
			switch (o) {
			case Pgsql::bool_oid:
				r = bool(value); //s = (s == "t") ? "TRUE" : "FALSE";
				break;
			default: {
				QString s = value;
				if (s.length() > 256) {
					s.truncate(256);
				}
				r = s;
				}
			}
		}
	}
	return r;
}

QVariant CrudModel::data(const QModelIndex &index, int role) const
{
	QVariant v;
	if (role == Qt::EditRole || role == Qt::DisplayRole) {
		v = getData(index);
	}
	else if (role == Qt::UserRole) {
		v = getType(index.column());
	}
	return v;
}


void CrudModel::loadData()
{
	QString table_name = genFQTableName(*m_database->catalogue(), m_table);
	std::string q = "SELECT * FROM ";
	q += table_name.toUtf8();
	m_dbConn.send(q, [this] (Expected<std::shared_ptr<Pgsql::Result>> res, qint64) {
		if (res.valid()) {
			auto dbres = res.get();
			if (dbres && *dbres) {
//				 WorkManager::getWorkManager()->addWork(
//					 [dbres, this] () -> void {
//						 std::shared_ptr<RowList> rl = resultToRowList(dbres);
//						 m_asyncWindow->QueueTask([this, rl]() { loadIntoModel(rl); });
//					 });
				 m_asyncWindow->QueueTask([this, dbres]() { loadIntoModel(dbres); });
			}
		}
		else {
//			emit onQueryError();
		}
	});
}

void CrudModel::loadIntoModel(std::shared_ptr<Pgsql::Result> data)
{
	beginResetModel();
	m_roData = data;
	endResetModel();
}

void CrudModel::connectionStateChanged(ASyncDBConnection::State state)
{
	switch (state) {
	case ASyncDBConnection::State::NotConnected:
		break;
	case ASyncDBConnection::State::Connecting:
		break;
	case ASyncDBConnection::State::Connected:
		if (callLoadData) {
			callLoadData = false;
			loadData();
		}
		break;
	case ASyncDBConnection::State::QuerySend:

		break;
	case ASyncDBConnection::State::CancelSend:
		break;
	case ASyncDBConnection::State::Terminating:
		break;
	}
}

Qt::ItemFlags CrudModel::flags(const QModelIndex &) const
{
	return Qt::ItemIsSelectable + Qt::ItemIsEditable + Qt::ItemIsEnabled;
}