/*
  Copyright 2011 Grégory Soutadé

  This file is part of KissCount.

  KissCount 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, either version 3 of the License, or
  (at your option) any later version.

  KissCount 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 KissCount.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "Database.h"

#define ON_ERROR(m)						\
    wxMessageBox(wxT(m), _("Error"), wxICON_ERROR | wxOK);	\
    throw std::string(m);

typedef void (*update_func)(wxSQLite3Database& _db) ;

#define UPDATE_TABLE(from, to, step) EXECUTE_SQL_UPDATE_WITH_CODE(req, , throw std::string("Error while upgrading from version " from " to version " to ", step " step);, });

static void Version_1_to_2(wxSQLite3Database& _db)
{
    wxString req ;
    wxSQLite3ResultSet set;

    /* Category */
    req = wxT("ALTER TABLE category ADD fix_cost CHAR(1)");

    UPDATE_TABLE("1", "2", "1");

    req = wxT("UPDATE category SET fix_cost='0'");

    UPDATE_TABLE("1", "2", "2");

    req = wxT("UPDATE category SET fix_cost='1' WHERE id IN (");
    req += wxT("SELECT MIN(category.id) FROM category, user WHERE category.user = user.id");
    req += wxT(")");

    UPDATE_TABLE("1", "2", "3");

    /* Account */
    req = wxT("ALTER TABLE account ADD virtual CHAR(1)");

    UPDATE_TABLE("1", "2", "4");

    req = wxT("UPDATE account SET virtual='0'");

    UPDATE_TABLE("1", "2", "5");

    /* Operation */
    req = wxT("ALTER TABLE operation ADD virtual CHAR(1)");

    UPDATE_TABLE("1", "2", "6");

    req = wxT("UPDATE operation SET virtual='0'");

    UPDATE_TABLE("1", "2", "7");    

    /* Import Pattern */
    req = wxT("CREATE TABLE import_pattern(id INTEGER PRIMARY KEY, user REFERENCES user(id), description VARCHAR(255), pattern VARCHAR(255), account REFERENCES account(id), category REFERENCES category(id))");

    UPDATE_TABLE("1", "2", "8");    
}

static update_func updates[] = {
    Version_1_to_2
};

void Database::CheckDatabaseVersion()
{
    wxString req ;
    wxSQLite3ResultSet set;
    long int version;
    int i;

    req = wxT("SELECT db_version FROM kisscount");

    EXECUTE_SQL_QUERY_WITH_CODE(req, set, , ON_ERROR("Unable to get database version"), {});

    if (!set.GetAsString(wxT("db_version")).ToLong(&version))
    {
	ON_ERROR("Invalid database version");
    }

    if (version == DATABASE_VERSION) return;

    if (version > DATABASE_VERSION)
    {
	ON_ERROR("Your current version of KissCount is too old and can't load this database. Please upgrade KissCount");	
    }

    version--;

    // Maybe one update is impossible
    for(i=version; i<DATABASE_VERSION-1; i++)
    {
	if (!updates[i])
	{
	    ON_ERROR("The database cannot be upgraded. Please use an older version of KissCount");	
	}
    }

    wxMessageDialog dialog(NULL, wxT("You use an old database model. KissCount will try to upgrade it to the lastest version"), wxT("KissCount"), wxICON_INFORMATION | wxOK | wxCANCEL);
    if (dialog.ShowModal() == wxID_CANCEL)
	throw std::string("can't load this database");

    _db.Begin();

    try
    {
	for(i=version; i<DATABASE_VERSION-1; i++)
	{
	    updates[i](_db);
	}
 
	req = wxT("UPDATE kisscount SET db_version='") + wxString::Format(wxT("%d"), DATABASE_VERSION) + wxT("'");

	EXECUTE_SQL_UPDATE_WITH_CODE(req, , throw std::string("Unable to set new database version"), {});
    }
    catch (std::string e)
    {
	std::cout << e << std::endl;

	_db.Rollback();
	
	throw e;
    }

    _db.Commit();

    wxMessageBox(wxT("Database upgrade successful !"), _("KissCount"), wxICON_INFORMATION | wxOK);
}