/* Copyright (C) 2014 InfiniDB, Inc.
   Copyright (C) 2016 MariaDB Corporation

   This program 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; version 2 of
   the License.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301, USA. */

/***********************************************************************
*   $Id: ha_view.cpp 9642 2013-06-24 14:57:42Z rdempsey $
*
*
***********************************************************************/

#include <my_config.h>
#include "idb_mysql.h"

#include <string>
using namespace std;

#include <boost/algorithm/string/case_conv.hpp>
using namespace boost;

#include "errorids.h"
using namespace logging;

#include "parsetree.h"
#include "simplefilter.h"
#include "calpontsystemcatalog.h"
using namespace execplan;

#include "ha_subquery.h"
#include "ha_view.h"

namespace cal_impl_if
{
extern uint32_t buildJoin(gp_walk_info& gwi, List<TABLE_LIST>& join_list,
    std::stack<execplan::ParseTree*>& outerJoinStack);
extern string getViewName(TABLE_LIST* table_ptr);

CalpontSystemCatalog::TableAliasName& View::viewName()
{
    return fViewName;
}

void View::viewName(execplan::CalpontSystemCatalog::TableAliasName& viewName)
{
    fViewName = viewName;
}

void View::transform()
{
    CalpontSelectExecutionPlan* csep = new CalpontSelectExecutionPlan();
    csep->sessionID(fParentGwip->sessionid);

    // gwi for the sub query
    gp_walk_info gwi;
    gwi.thd = fParentGwip->thd;

    uint32_t sessionID = csep->sessionID();
    gwi.sessionid = sessionID;
    boost::shared_ptr<CalpontSystemCatalog> csc = CalpontSystemCatalog::makeCalpontSystemCatalog(sessionID);
    csc->identity(CalpontSystemCatalog::FE);
    gwi.csc = csc;

    // traverse the table list of the view
    TABLE_LIST* table_ptr = fSelect.get_table_list();
    CalpontSelectExecutionPlan::SelectList derivedTbList;

    // @bug 1796. Remember table order on the FROM list.
    gwi.clauseType = FROM;

    try
    {
        for (; table_ptr; table_ptr = table_ptr->next_local)
        {
            // mysql put vtable here for from sub. we ignore it
            if (string(table_ptr->table_name.str).find("$vtable") != string::npos)
                continue;

            string viewName = getViewName(table_ptr);
            if (lower_case_table_names)
            {
                boost::algorithm::to_lower(viewName);
            }

            if (table_ptr->derived)
            {
                SELECT_LEX* select_cursor = table_ptr->derived->first_select();
                FromSubQuery* fromSub = new FromSubQuery(gwi, select_cursor);
                string alias(table_ptr->alias.str);
                if (lower_case_table_names)
                {
                    boost::algorithm::to_lower(alias);
                }
                gwi.viewName = make_aliasview("", alias, table_ptr->belong_to_view->alias.str, "", true, lower_case_table_names);
                fromSub->alias(alias);
                gwi.derivedTbList.push_back(SCSEP(fromSub->transform()));
                // set alias to both table name and alias name of the derived table
                CalpontSystemCatalog::TableAliasName tn = make_aliasview("", "", alias, viewName);
                gwi.tbList.push_back(tn);
                gwi.tableMap[tn] = make_pair(0, table_ptr);
                // TODO MCOL-2178 isUnion member only assigned, never used
                // MIGR::infinidb_vtable.isUnion = true; //by-pass the 2nd pass of rnd_init
            }
            else if (table_ptr->view)
            {
                // for nested view, the view name is vout.vin... format
                CalpontSystemCatalog::TableAliasName tn = make_aliasview(table_ptr->db.str, table_ptr->table_name.str, table_ptr->alias.str, viewName, true, lower_case_table_names);
                gwi.viewName = make_aliastable(table_ptr->db.str, table_ptr->table_name.str, viewName, true, lower_case_table_names);
                View* view = new View(*table_ptr->view->first_select_lex(), &gwi);
                view->viewName(gwi.viewName);
                gwi.viewList.push_back(view);
                view->transform();
            }
            else
            {
                // check foreign engine tables
                bool columnStore = (table_ptr->table ? isMCSTable(table_ptr->table) : true);

                // trigger system catalog cache
                if (columnStore)
                    csc->columnRIDs(make_table(table_ptr->db.str, table_ptr->table_name.str, lower_case_table_names), true);

                CalpontSystemCatalog::TableAliasName tn = make_aliasview(table_ptr->db.str, table_ptr->table_name.str, table_ptr->alias.str, viewName, columnStore, lower_case_table_names);
                gwi.tbList.push_back(tn);
                gwi.tableMap[tn] = make_pair(0, table_ptr);
                fParentGwip->tableMap[tn] = make_pair(0, table_ptr);
            }
        }

        if (gwi.fatalParseError)
        {
            setError(gwi.thd, ER_INTERNAL_ERROR, gwi.parseErrorText);
            return;
        }
    }
    catch (IDBExcept& ie)
    {
        setError(gwi.thd, ER_INTERNAL_ERROR, ie.what());
        CalpontSystemCatalog::removeCalpontSystemCatalog(sessionID);
        return;
    }
    catch (...)
    {
        string emsg = IDBErrorInfo::instance()->errorMsg(ERR_LOST_CONN_EXEMGR);
        setError(gwi.thd, ER_INTERNAL_ERROR, emsg);
        CalpontSystemCatalog::removeCalpontSystemCatalog(sessionID);
        return;
    }

    // merge table list to parent select
    fParentGwip->tbList.insert(fParentGwip->tbList.end(), gwi.tbList.begin(), gwi.tbList.end());
    fParentGwip->derivedTbList.insert(fParentGwip->derivedTbList.end(), gwi.derivedTbList.begin(), gwi.derivedTbList.end());
    fParentGwip->correlatedTbNameVec.insert(fParentGwip->correlatedTbNameVec.end(), gwi.correlatedTbNameVec.begin(), gwi.correlatedTbNameVec.end());

    // merge view list to parent
    fParentGwip->viewList.insert(fParentGwip->viewList.end(), gwi.viewList.begin(), gwi.viewList.end());

    // merge non-collapsed outer join to parent select
    stack<ParseTree*> tmpstack;

    while (!gwi.ptWorkStack.empty())
    {
        tmpstack.push(gwi.ptWorkStack.top());
        gwi.ptWorkStack.pop();
    }

    while (!tmpstack.empty())
    {
        fParentGwip->ptWorkStack.push(tmpstack.top());
        tmpstack.pop();
    }
}

uint32_t View::processJoin(gp_walk_info& gwi, std::stack<execplan::ParseTree*>& outerJoinStack)
{
    return buildJoin(gwi, fSelect.top_join_list, outerJoinStack);
}

}
