/****************************************************************************
**
** https://www.qxorm.com/
** Copyright (C) 2013 XDL Team (ic-east.com)
**
** This file is part of the QxOrm library
**
** This software is provided 'as-is', without any express or implied
** warranty. In no event will the authors be held liable for any
** damages arising from the use of this software
**
** Commercial Usage
** Licensees holding valid commercial QxOrm licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and XDL Team
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file 'license.gpl3.txt' included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met : http://www.gnu.org/copyleft/gpl.html
**
** If you are unsure which license is appropriate for your use, or
** if you have questions regarding the use of this file, please contact :
** ic-east.com
**
****************************************************************************/

namespace qx
{
   namespace dao
   {
      namespace detail
      {

         template <class T>
         struct QxDao_FetchById_Generic
         {

            static QSqlError fetchById(T &t, QSqlDatabase *pDatabase, const QStringList &columns)
            {
               qx::dao::detail::QxDao_Helper<T> dao(t, pDatabase, "fetch by id", new qx::QxSqlQueryBuilder_FetchById<T>());
               if (!dao.isValid())
               {
                  return dao.error();
               }
               if (!dao.isValidPrimaryKey(t))
               {
                  return dao.errInvalidId();
               }

#ifdef _QX_ENABLE_MONGODB
               if (dao.isMongoDB())
               {
                  dao.setSqlColumns(columns);
                  qx::dao::on_before_fetch<T>((&t), (&dao));
                  if (!dao.isValid())
                  {
                     return dao.error();
                  }
                  QString json = qx::serialization::json::to_string(t, 1, "mongodb:only_id");
                  qx::dao::mongodb::QxMongoDB_Helper::findOne((&dao), dao.getDataMemberX()->getClass(), json, NULL);
                  if (!dao.isValid())
                  {
                     return dao.error();
                  }

                  qx::dao::detail::IxDao_Timer timer((&dao), qx::dao::detail::IxDao_Helper::timer_cpp_build_instance);
                  QString ctx = QString("mongodb") + ((columns.count() > 0) ? (QString(":columns{,") + columns.join(",") + QString(",}")) : QString());
                  qx::serialization::json::from_string(t, json, 1, ctx);
                  qx::dao::on_after_fetch<T>((&t), (&dao));
                  if (!dao.isValid())
                  {
                     return dao.error();
                  }
                  return dao.error();
               }
#endif // _QX_ENABLE_MONGODB

               QString sql = dao.builder().buildSql(columns).getSqlQuery();
               if (!dao.getDataId() || sql.isEmpty())
               {
                  return dao.errEmpty();
               }
               if (!dao.prepare(sql))
               {
                  return dao.errFailed(true);
               }

               {
                  qx::dao::on_before_fetch<T>((&t), (&dao));
                  if (!dao.isValid())
                  {
                     return dao.error();
                  }
                  qx::dao::detail::IxDao_Timer timer((&dao), qx::dao::detail::IxDao_Helper::timer_cpp_read_instance);
                  qx::dao::detail::QxSqlQueryHelper_FetchById<T>::resolveInput(t, dao.query(), dao.builder(), columns);
               }

               if (!dao.exec(true))
               {
                  return dao.errFailed();
               }
               if (!dao.nextRecord())
               {
                  return dao.errNoData();
               }

               {
                  qx::dao::detail::IxDao_Timer timer((&dao), qx::dao::detail::IxDao_Helper::timer_cpp_build_instance);
                  qx::dao::detail::QxSqlQueryHelper_FetchById<T>::resolveOutput(t, dao.query(), dao.builder(), columns);
                  qx::dao::on_after_fetch<T>((&t), (&dao));
               }

               return dao.error();
            }
         };

         template <class T>
         struct QxDao_FetchById_Container
         {

            static QSqlError fetchById(T &t, QSqlDatabase *pDatabase, const QStringList &columns)
            {
               typedef typename qx::trait::generic_container<T>::type_value_qx type_item;

               if (qx::trait::generic_container<T>::size(t) <= 0)
               {
                  return QSqlError();
               }
               qx::dao::detail::QxDao_Helper_Container<T> dao(t, pDatabase, "fetch by id", new qx::QxSqlQueryBuilder_FetchById<type_item>());
               if (!dao.isValid())
               {
                  return dao.error();
               }

#ifdef _QX_ENABLE_MONGODB
               if (dao.isMongoDB())
               {
                  dao.setSqlColumns(columns);
                  for (typename T::iterator it = t.begin(); it != t.end(); ++it)
                  {
                     if (!fetchItem((*it), dao))
                     {
                        return dao.error();
                     }
                  }
                  QStringList &itemsAsJson = dao.itemsAsJson();
                  qx::dao::mongodb::QxMongoDB_Helper::findMany((&dao), dao.getDataMemberX()->getClass(), itemsAsJson, NULL, NULL);
                  if (!dao.isValid())
                  {
                     return dao.error();
                  }
                  dao.qxQuery().queryAt(2, "<done>");
                  for (typename T::iterator it = t.begin(); it != t.end(); ++it)
                  {
                     if (!fetchItem((*it), dao))
                     {
                        return dao.error();
                     }
                  }
                  return dao.error();
               }
#endif // _QX_ENABLE_MONGODB

               QString sql = dao.builder().buildSql(columns).getSqlQuery();
               if (!dao.getDataId() || sql.isEmpty())
               {
                  return dao.errEmpty();
               }
               if (!dao.prepare(sql))
               {
                  return dao.errFailed(true);
               }
               dao.setSqlColumns(columns);

               for (typename T::iterator it = t.begin(); it != t.end(); ++it)
               {
                  if (!fetchItem((*it), dao))
                  {
                     return dao.error();
                  }
               }

               return dao.error();
            }

         private:
            template <typename U>
            static inline bool fetchItem(U &item, qx::dao::detail::QxDao_Helper_Container<T> &dao)
            {
               bool bFetchOk = fetchItem_Helper < U, std::is_pointer<U>::value || qx::trait::is_smart_ptr<U>::value > ::fetch(item, dao);
               if (bFetchOk)
               {
                  qx::dao::detail::QxDao_Keep_Original<U>::backup(item);
               }
               return bFetchOk;
            }

            template <typename U, bool bIsPointer /* = true */>
            struct fetchItem_Helper
            {
               static inline bool fetch(U &item, qx::dao::detail::QxDao_Helper_Container<T> &dao)
               {
                  return (item ? qx::dao::detail::QxDao_FetchById_Container<T>::fetchItem((*item), dao) : true);
               }
            };

            template <typename U1, typename U2>
            struct fetchItem_Helper<std::pair<U1, U2>, false>
            {
               static inline bool fetch(std::pair<U1, U2> &item, qx::dao::detail::QxDao_Helper_Container<T> &dao)
               {
                  return qx::dao::detail::QxDao_FetchById_Container<T>::fetchItem(item.second, dao);
               }
            };

            template <typename U1, typename U2>
            struct fetchItem_Helper<const std::pair<U1, U2>, false>
            {
               static inline bool fetch(const std::pair<U1, U2> &item, qx::dao::detail::QxDao_Helper_Container<T> &dao)
               {
                  return qx::dao::detail::QxDao_FetchById_Container<T>::fetchItem(item.second, dao);
               }
            };

#if (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
            template <typename U1, typename U2>
            struct fetchItem_Helper<QPair<U1, U2>, false>
            {
               static inline bool fetch(QPair<U1, U2> &item, qx::dao::detail::QxDao_Helper_Container<T> &dao)
               {
                  return qx::dao::detail::QxDao_FetchById_Container<T>::fetchItem(item.second, dao);
               }
            };

            template <typename U1, typename U2>
            struct fetchItem_Helper<const QPair<U1, U2>, false>
            {
               static inline bool fetch(const QPair<U1, U2> &item, qx::dao::detail::QxDao_Helper_Container<T> &dao)
               {
                  return qx::dao::detail::QxDao_FetchById_Container<T>::fetchItem(item.second, dao);
               }
            };
#endif // (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))

            template <typename U>
            struct fetchItem_Helper<U, false>
            {
               static bool fetch(U &item, qx::dao::detail::QxDao_Helper_Container<T> &dao)
               {
                  QStringList columns = dao.getSqlColumns();
                  if (!dao.isValidPrimaryKey(item))
                  {
                     dao.errInvalidId();
                     return false;
                  }

#ifdef _QX_ENABLE_MONGODB
                  if (dao.isMongoDB())
                  {
                     if (dao.qxQuery().queryAt(2) == "<done>")
                     {
                        qx::dao::detail::IxDao_Timer timer((&dao), qx::dao::detail::IxDao_Helper::timer_cpp_build_instance);
                        QString ctx = QString("mongodb") + ((columns.count() > 0) ? (QString(":columns{,") + columns.join(",") + QString(",}")) : QString());
                        if (!dao.itemsAsJson().isEmpty())
                        {
                           QString json = dao.itemsAsJson().takeFirst();
                           if (!json.isEmpty())
                           {
                              qx::serialization::json::from_string(item, json, 1, ctx);
                           }
                        }
                        qx::dao::on_after_fetch<U>((&item), (&dao));
                        return dao.isValid();
                     }
                     {
                        qx::dao::on_before_fetch<U>((&item), (&dao));
                        if (!dao.isValid())
                        {
                           return false;
                        }
                        QVariant id = (dao.getDataId() ? dao.getDataId()->toVariant(&item) : QVariant());
                        if (!id.isNull() && !id.toString().isEmpty())
                        {
                           dao.itemsAsJson().append(id.toString());
                        }
                     }
                     return dao.isValid();
                  }
#endif // _QX_ENABLE_MONGODB

                  {
                     qx::dao::on_before_fetch<U>((&item), (&dao));
                     if (!dao.isValid())
                     {
                        return false;
                     }
                     qx::dao::detail::IxDao_Timer timer((&dao), qx::dao::detail::IxDao_Helper::timer_cpp_read_instance);
                     qx::dao::detail::QxSqlQueryHelper_FetchById<U>::resolveInput(item, dao.query(), dao.builder(), columns);
                  }

                  if (!dao.exec(true))
                  {
                     dao.errFailed();
                     return false;
                  }
                  if (!dao.nextRecord())
                  {
                     dao.errNoData();
                     return false;
                  }

                  {
                     qx::dao::detail::IxDao_Timer timer((&dao), qx::dao::detail::IxDao_Helper::timer_cpp_build_instance);
                     qx::dao::detail::QxSqlQueryHelper_FetchById<U>::resolveOutput(item, dao.query(), dao.builder(), columns);
                     qx::dao::on_after_fetch<U>((&item), (&dao));
                  }

                  return dao.isValid();
               }
            };
         };

         template <class T>
         struct QxDao_FetchById_Ptr
         {

            static inline QSqlError fetchById(T &t, QSqlDatabase *pDatabase, const QStringList &columns)
            {
               if (!t)
               {
                  qx::trait::construct_ptr<T>::get(t);
               };
               return qx::dao::fetch_by_id((*t), pDatabase, columns);
            }
         };

         template <class T>
         struct QxDao_FetchById
         {

            static inline QSqlError fetchById(T &t, QSqlDatabase *pDatabase, const QStringList &columns)
            {
               typedef typename std::conditional<std::is_pointer<T>::value, qx::dao::detail::QxDao_FetchById_Ptr<T>, qx::dao::detail::QxDao_FetchById_Generic<T>>::type type_dao_1;
               typedef typename std::conditional<qx::trait::is_smart_ptr<T>::value, qx::dao::detail::QxDao_FetchById_Ptr<T>, type_dao_1>::type type_dao_2;
               typedef typename std::conditional<qx::trait::is_container<T>::value, qx::dao::detail::QxDao_FetchById_Container<T>, type_dao_2>::type type_dao_3;

               QSqlError error = type_dao_3::fetchById(t, pDatabase, columns);
               if (!error.isValid())
               {
                  qx::dao::detail::QxDao_Keep_Original<T>::backup(t);
               }
               return error;
            }
         };

      } // namespace detail
   } // namespace dao
} // namespace qx