src/config.cc

/*
 *  LDForge: LDraw parts authoring CAD
 *  Copyright (C) 2013 Santeri Piippo
 *
 *  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 3 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, see <http://www.gnu.org/licenses/>.
 *  =====================================================================
 *
 *  config.cpp: Configuration management. I don't like how unsafe QSettings
 *  is so this implements a type-safer and identifer-safer wrapping system of
 *  configuration variables. QSettings is used underlyingly, this is a matter
 *  of interface.
 */

#include <errno.h>
#include <QDir>
#include <QTextStream>
#include <QSettings>
#include "main.h"
#include "config.h"
#include "misc.h"
#include "gui.h"
#include "document.h"

#ifdef _WIN32
# define EXTENSION ".ini"
#else
# define EXTENSION ".cfg"
#endif // _WIN32

Config* g_configPointers[MAX_CONFIG];
static int g_cfgPointerCursor = 0;

// =============================================================================
// Get the QSettings object. A portable build refers to a file in the current
// directory, a non-portable build to ~/.config/LDForge or to registry.
// -----------------------------------------------------------------------------
static QSettings* getSettingsObject()
{
#ifdef PORTABLE
	return new QSettings (str (APPNAME).toLower() + EXTENSION, QSettings::IniFormat);
#else
	return new QSettings;
#endif // PORTABLE
}

Config::Config (const char* name, const char* defstring) :
	name (name), m_defstring (defstring) {}

// =============================================================================
// Load the configuration from file
// -----------------------------------------------------------------------------
bool Config::load()
{	QSettings* settings = getSettingsObject();
	log ("config::load: Loading configuration file from %1\n", settings->fileName());

	for (Config* cfg : g_configPointers)
	{	if (!cfg)
			break;

		QVariant val = settings->value (cfg->name, cfg->defaultVariant());
		cfg->loadFromVariant (val);
	}

	settings->deleteLater();
	return true;
}

// =============================================================================
// Save the configuration to disk
// -----------------------------------------------------------------------------
bool Config::save()
{	QSettings* settings = getSettingsObject();
	log ("Saving configuration to %1...\n", settings->fileName());

	for (Config* cfg : g_configPointers)
	{	if (!cfg)
			break;

		if (cfg->isDefault())
			continue;

		settings->setValue (cfg->name, cfg->toVariant());
	}

	settings->sync();
	settings->deleteLater();
	return true;
}

// =============================================================================
// Reset configuration defaults.
// -----------------------------------------------------------------------------
void Config::reset()
{	for (Config * cfg : g_configPointers)
	{	if (!cfg)
			break;

		cfg->resetValue();
	}
}

// =============================================================================
// Where is the configuration file located at? Note that the Windows build uses
// the registry so only use this with PORTABLE code.
// -----------------------------------------------------------------------------
str Config::filepath (str file)
{	return Config::dirpath() + DIRSLASH + file;
}

// =============================================================================
// Directory of the configuration file. PORTABLE code here as well.
// -----------------------------------------------------------------------------
str Config::dirpath()
{	QSettings* cfg = getSettingsObject();
	return dirname (cfg->fileName());
}

// =============================================================================
// We cannot just add config objects to a list or vector because that would rely
// on the vector's c-tor being called before the configs' c-tors. With global
// variables we cannot assume that!! Therefore we need to use a C-style array here.
// -----------------------------------------------------------------------------
void Config::addToArray (Config* ptr)
{	if (g_cfgPointerCursor == 0)
		memset (g_configPointers, 0, sizeof g_configPointers);

	assert (g_cfgPointerCursor < MAX_CONFIG);
	g_configPointers[g_cfgPointerCursor++] = ptr;
}

// =============================================================================
// -----------------------------------------------------------------------------
template<class T> T& getConfigByName (str name, Config::Type type)
{	for (Config* cfg : g_configPointers)
	{	if (!cfg)
			break;

		if (cfg->name == name)
		{	assert (cfg->getType() == type);
			return *(reinterpret_cast<T*> (cfg));
		}
	}

	qFatal ("couldn't find a configuration element with name %s", name.toLocal8Bit().constData());
	abort();
}

#undef IMPLEMENT_CONFIG
#define IMPLEMENT_CONFIG(NAME) \
	NAME##Config& NAME##Config::getByName (str name) { return getConfigByName<NAME##Config> (name, NAME); }

IMPLEMENT_CONFIG (Int)
IMPLEMENT_CONFIG (String)
IMPLEMENT_CONFIG (Bool)
IMPLEMENT_CONFIG (Float)
IMPLEMENT_CONFIG (List)
IMPLEMENT_CONFIG (KeySequence)