/****************************************************************************
**
** 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
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** 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 :
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****************************************************************************/

#ifndef _QX_SQL_RELATION_MANY_TO_MANY_H_
#define _QX_SQL_RELATION_MANY_TO_MANY_H_

#ifdef _MSC_VER
#pragma once
#endif

/*!
 * \file QxSqlRelation_ManyToMany.h
 * \author XDL Team
 * \ingroup QxDao
 * \brief Manage a relationship many-to-many defined between 2 classes (or between 2 tables in database)
 */

#include <QxDao/QxSqlRelation.h>

namespace qx
{

   /*!
    * \ingroup QxDao
    * \brief qx::QxSqlRelation_ManyToMany<DataType, Owner> : manage a relationship many-to-many defined between 2 classes (or between 2 tables in database)
    */
   template <class DataType, class Owner>
   class QxSqlRelation_ManyToMany : public QxSqlRelation<DataType, Owner>
   {

   private:
      typedef typename QxSqlRelation<DataType, Owner>::type_owner type_owner;
      typedef typename QxSqlRelation<DataType, Owner>::type_data type_data;
      typedef typename QxSqlRelation<DataType, Owner>::type_container type_container;
      typedef typename QxSqlRelation<DataType, Owner>::type_generic_container type_generic_container;
      typedef typename QxSqlRelation<DataType, Owner>::type_item type_item;
      typedef typename type_generic_container::type_iterator type_iterator;
      typedef typename type_item::type_value type_value;

      enum
      {
         is_data_container = QxSqlRelation<DataType, Owner>::is_data_container
      };

   public:
      QxSqlRelation_ManyToMany(IxDataMember *p, const QString &sExtraTable, const QString &sForeignKeyOwner, const QString &sForeignKeyDataType) : QxSqlRelation<DataType, Owner>(p)
      {
         this->setRelationType(qx::IxSqlRelation::many_to_many);
         this->setExtraTable(sExtraTable);
         this->setForeignKeyOwner(sForeignKeyOwner);
         this->setForeignKeyDataType(sForeignKeyDataType);
         this->verifyParameters();
      }
      virtual ~QxSqlRelation_ManyToMany() { static_assert(is_data_container, "is_data_container"); }

      virtual QString getDescription() const { return "relation many-to-many"; }
      virtual bool getCartesianProduct() const { return true; }
      virtual void createTable(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazySelect(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazyFrom(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void eagerFrom(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazyJoin(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazyWhere(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void eagerWhere(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazyWhereSoftDelete(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazyFetch_ResolveInput(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void eagerFetch_ResolveInput(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazyFetch_ResolveOutput(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazyInsert(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazyInsert_Values(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazyUpdate(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazyInsert_ResolveInput(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual void lazyUpdate_ResolveInput(QxSqlRelationParams &params) const { Q_UNUSED(params); }
      virtual QSqlError onBeforeSave(QxSqlRelationParams &params) const
      {
         Q_UNUSED(params);
         return QSqlError();
      }

      virtual QVariant getIdFromQuery(bool bEager, QxSqlRelationParams &params, int iOffset, int iNameIndex) const
      {
         return this->getIdFromQuery_ManyToMany(bEager, params, iOffset, iNameIndex);
      }

      virtual void updateOffset(bool bEager, QxSqlRelationParams &params) const
      {
         this->updateOffset_ManyToMany(bEager, params);
      }

      virtual void eagerSelect(QxSqlRelationParams &params) const
      {
         this->eagerSelect_ManyToMany(params);
      }

      virtual void eagerJoin(QxSqlRelationParams &params) const
      {
         this->eagerJoin_ManyToMany(params);
      }

      virtual void eagerWhereSoftDelete(QxSqlRelationParams &params) const
      {
         this->eagerWhereSoftDelete_ManyToMany(params);
      }

      virtual void *eagerFetch_ResolveOutput(QxSqlRelationParams &params) const
      {
         if (!this->verifyOffset(params, true))
         {
            return NULL;
         }
         QSqlQuery &query = params.query();
         IxDataMember *p = NULL;
         IxDataMember *pId = this->getDataId();
         qAssert(pId);
         long lIndex = 0;
         long lOffsetId = ((pId && (!params.isDistinct())) ? pId->getNameCount() : 0);
         bool bValidId(false);
         long lOffsetOld = params.offset();
         this->updateOffset(true, params);
         long lRelation = 0;
         IxSqlRelation *pRelation = NULL;

         if (!params.isDistinct())
         {
            for (int i = 0; i < pId->getNameCount(); i++)
            {
               QVariant v = query.value(lOffsetOld + i);
               bValidId = (bValidId || qx::trait::is_valid_primary_key(v));
            }
            if (!bValidId)
            {
               return NULL;
            }
         }

         type_item item = this->createItem();
         type_data &item_val = item.value_qx();
         if (!this->callTriggerBeforeFetch(item_val, params))
         {
            return NULL;
         }

         if (!params.isDistinct())
         {
            for (int i = 0; i < pId->getNameCount(); i++)
            {
               QVariant v = query.value(lOffsetOld + i);
               qx::cvt::from_variant(v, item.key(), "", i, qx::cvt::context::e_database);
            }
            for (int i = 0; i < pId->getNameCount(); i++)
            {
               QVariant v = query.value(lOffsetOld + i);
               pId->fromVariant((&item_val), v, "", i, qx::cvt::context::e_database);
            }
         }
         else
         {
            for (int i = 0; i < pId->getNameCount(); i++)
            {
               QVariant v = this->getIdFromQuery(true, params, (lOffsetOld + i), i);
               qx::cvt::from_variant(v, item.key(), "", i, qx::cvt::context::e_database);
            }
         }

         long lOffsetRelation = (lOffsetOld + lOffsetId);
         long lCurrIndex = 0;
         while ((p = this->nextData(lIndex)))
         {
            if (params.checkColumns(p->getKey()))
            {
               p->fromVariant((&item_val), query.value(lCurrIndex + lOffsetRelation), -1, qx::cvt::context::e_database);
               lCurrIndex++;
            }
         }

         if (params.relationX())
         {
            long lOffsetCurrent = (lCurrIndex + lOffsetRelation);
            QString sOldCustomAliasOwner = params.getCustomAliasOwner();
            params.setCustomAliasOwner(params.getCustomAlias());
            long lIndexOwnerOld = params.indexOwner();
            params.setIndexOwner(params.index());
            void *pOwnerOld = params.owner();
            params.setOwner(&item_val);
            lOffsetOld = params.offset();
            params.setOffset(lOffsetCurrent);
            while ((pRelation = this->nextRelation(lRelation)))
            {
               if (this->addLazyRelation(params, pRelation))
               {
                  pRelation->lazyFetch_ResolveOutput(params);
               }
            }
            params.setOwner(pOwnerOld);
            params.setOffset(lOffsetOld);
            params.setCustomAliasOwner(sOldCustomAliasOwner);
            params.setIndexOwner(lIndexOwnerOld);
         }

         if (!this->callTriggerAfterFetch(item_val, params))
         {
            return NULL;
         }
         type_value *pValue = type_generic_container::insertItem(this->getContainer(params), item);
         if (!type_item::is_value_pointer && pValue)
         {
            return pValue;
         }
         return (&item_val);
      }

      virtual QSqlError onAfterSave(QxSqlRelationParams &params) const
      {
         QSqlError daoError;
         if (this->isNullData(params))
         {
            return this->deleteFromExtraTable(params);
         }
         if (!params.recursiveMode())
         {
            daoError = qx::dao::save(this->getContainer(params), (&params.database()));
         }
         else
         {
            daoError = qx::dao::save_with_relation_recursive(this->getContainer(params), params.saveMode(), (&params.database()), (&params));
         }
         if (daoError.isValid())
         {
            return daoError;
         }
         daoError = this->deleteFromExtraTable(params);
         if (daoError.isValid())
         {
            return daoError;
         }
         daoError = this->insertIntoExtraTable(params);
         if (daoError.isValid())
         {
            return daoError;
         }
         return QSqlError();
      }

      virtual QString createExtraTable() const
      {
         return this->createExtraTable_ManyToMany();
      }

   private:
      void verifyParameters()
      {
         qAssert(!this->getExtraTable().isEmpty() && !this->getForeignKeyOwner().isEmpty() && !this->getForeignKeyDataType().isEmpty() && (this->getForeignKeyOwner() != this->getForeignKeyDataType()));
      }

      QSqlError deleteFromExtraTable(QxSqlRelationParams &params) const
      {
         return this->deleteFromExtraTable_ManyToMany(params);
      }

      QSqlError insertIntoExtraTable(QxSqlRelationParams &params) const
      {
         IxDataMember *pIdOwner = this->getDataIdOwner();
         qAssert(pIdOwner);
         IxDataMember *pIdData = this->getDataId();
         qAssert(pIdData);
         if (!pIdOwner || !pIdData)
         {
            return QSqlError();
         }
         QStringList lstForeignKeyOwner = this->getForeignKeyOwner().split("|");
         QStringList lstForeignKeyDataType = this->getForeignKeyDataType().split("|");
         qAssert(pIdOwner->getNameCount() == lstForeignKeyOwner.count());
         qAssert(pIdData->getNameCount() == lstForeignKeyDataType.count());

         QString sql = "INSERT INTO " + this->getExtraTable() + " (";
         sql += pIdOwner->getSqlName(", ", this->getForeignKeyOwner(), false, (&params.builder()));
         sql += ", ";
         sql += pIdData->getSqlName(", ", this->getForeignKeyDataType(), false, (&params.builder()));
         sql += ") VALUES (";
         sql += pIdOwner->getSqlPlaceHolder("", -1, ", ", this->getForeignKeyOwner()) + ", " + pIdData->getSqlPlaceHolder("", -1, ", ", this->getForeignKeyDataType()) + ")";
         if (this->traceSqlQuery())
         {
            qDebug("[QxOrm] sql query (extra-table) : %s", qPrintable(sql));
         }

         type_item item;
         type_container &container = this->getContainer(params);
         type_iterator itr = type_generic_container::begin(container, item);
         type_iterator itr_end = type_generic_container::end(container);
         QSqlQuery queryInsert(params.database());
         if (!queryInsert.prepare(sql))
         {
            return queryInsert.lastError();
         }

         while (itr != itr_end)
         {
            pIdOwner->setSqlPlaceHolder(queryInsert, params.owner(), "", this->getForeignKeyOwner());
            pIdData->setSqlPlaceHolder(queryInsert, (&item.value_qx()), "", this->getForeignKeyDataType());
            if (!queryInsert.exec())
            {
               return queryInsert.lastError();
            }
            itr = type_generic_container::next(container, itr, item);
         }

         return QSqlError();
      }
   };

} // namespace qx

#endif // _QX_SQL_RELATION_MANY_TO_MANY_H_