kicad/include/config_map.h

117 lines
3.3 KiB
C++

/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2017 Kicad Developers, see change_log.txt for contributors.
*
* 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; either version 2
* of the License, or (at your option) any later version.
*
* 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, you may find one here:
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
* or you may search the http://www.gnu.org website for the version 2 license,
* or you may write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#ifndef CONFIG_MAP__H_
#define CONFIG_MAP__H_
#include <map>
namespace UTIL
{
/**
* A config value table is a list of native values (usually enums)
* to a different set of values, for example, the values used to
* represent the enum in a config file, or the index used to represent
* it in a selection list.
*
* It can be important to decouple from the internal representation,
* especially in the case of persistent config files, as adding,
* removing or modifying the order of items internally can easily
* result in configs being read incorrectly, and, even if otherwise
* carefully managed, results in obsolete values being kept in enums
* as placeholders.
*
* The first item in the list is used default if no matching value is
* found during lookup.
*/
template<typename T>
using CFG_MAP = std::vector<std::pair<T, long> >;
/**
* The "native" type of a CFG_MAP: probably an enum type
*/
template<typename MAP>
using CFG_NATIVE_VAL = typename MAP::value_type::first_type;
/**
* Get the mapped config value (the one to write to file, or use in
* an index) from the given native (probably enum) value.
*
* The default (first item) is returned if the value is not found
* in the list.
*
* @param aMap the value-config mapping table
* @param aVal the value to look up
*/
template<typename MAP>
static long GetConfigForVal( const MAP& aMap, CFG_NATIVE_VAL<MAP> aVal )
{
// default is first entry
long aConf = aMap[0].second;
for( const auto& mapping : aMap )
{
if( mapping.first == aVal )
{
aConf = mapping.second;
break;
}
}
return aConf;
}
/**
* Get the native value corresponding to the config value
* (read from file or UI, probably) and find it in the mapping table.
*
* The default item is returned if the mapping fails.
*
* @param aMap the value-config mapping table
* @param aVal the config value to look up
*/
template<typename MAP>
static CFG_NATIVE_VAL<MAP> GetValFromConfig(
const MAP& aMap, long aConf )
{
// default is first entry
CFG_NATIVE_VAL<MAP> aVal = aMap[0].first;
for( const auto& mapping : aMap )
{
if( mapping.second == aConf )
{
aVal = mapping.first;
break;
}
}
return aVal;
}
}
#endif /* CONFIG_MAP__H_ */