#include "dbtransaction.h"
#include "ngldb_logger.h"
#include <QtSql/QSqlError>

thread_local int s_refCounter = 0;

DBTransaction::DBTransaction(const QSqlDatabase &db)
  : m_db(db)
  , m_bCommitted(true)
  , mLogger(NGLDB::getLogger("DBTransaction"))
{
  ++s_refCounter;
  if (s_refCounter == 1)
    begin();
}

DBTransaction::~DBTransaction()
{
  if (s_refCounter == 1)
  {
    if (!m_bCommitted)
      rollback();
  }
  --s_refCounter;
}

bool DBTransaction::begin()
{
  if (!m_bCommitted)
    return setState(false);
  if (!m_db.transaction())
  {
    ERROR_LOG(mLogger) << "Error starting a transaction: " << m_db.lastError().driverText();
    return setState(false);
  }
  m_bCommitted = false;
  return setState(true);
}

bool DBTransaction::commit()
{
  if (s_refCounter == 1)
  {
    if (!m_db.commit())
    {
      ERROR_LOG(mLogger) << "Error committing a transaction: " << m_db.lastError().driverText();
      return setState(false);
    }
    m_bCommitted = true;
    return setState(true);
  }
  return true;
}

bool DBTransaction::rollback()
{
  if (s_refCounter == 1)
  {
    if (!m_db.rollback())
    {
      ERROR_LOG(mLogger) << "Error rolling back a transaction" << m_db.lastError().driverText();
      return setState(false);
    }
    m_bCommitted = true;
    return setState(true);
  }
  return true;
}

bool DBTransaction::state() const
{
  return m_lastState;
}

bool DBTransaction::setState(bool bState)
{
  m_lastState = bState;
  return m_lastState;
}