/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 */

#include <time.h>
#ifdef POSIX
#include <sys/time.h>
#include <unistd.h>
#include <signal.h>
#endif

// We use some stdio.h functionality here thus we need to allow some
// symbols. Alternatively, we could simply allow everything by defining
// FORBIDDEN_SYMBOL_ALLOW_ALL
#define FORBIDDEN_SYMBOL_EXCEPTION_FILE
#define FORBIDDEN_SYMBOL_EXCEPTION_stdout
#define FORBIDDEN_SYMBOL_EXCEPTION_stderr
#define FORBIDDEN_SYMBOL_EXCEPTION_fputs
#define FORBIDDEN_SYMBOL_EXCEPTION_exit
#define FORBIDDEN_SYMBOL_EXCEPTION_time_h

#include "backends/modular-backend.h"
#include "base/main.h"

#if defined(USE_NULL_DRIVER)
#include "backends/saves/default/default-saves.h"
#include "backends/timer/default/default-timer.h"
#include "backends/events/default/default-events.h"
#include "backends/mixer/null/null-mixer.h"
#include "backends/mutex/null/null-mutex.h"
#include "backends/graphics/null/null-graphics.h"
#include "audio/mixer_intern.h"
#include "common/scummsys.h"
#include "gui/debugger.h"

/*
 * Include header files needed for the getFilesystemFactory() method.
 */
#if defined(__amigaos4__)
	#include "backends/fs/amigaos4/amigaos4-fs-factory.h"
#elif defined(__MORPHOS__)
	#include "backends/fs/morphos/morphos-fs-factory.h"
#elif defined(POSIX)
	#include "backends/fs/posix/posix-fs-factory.h"
#elif defined(RISCOS)
	#include "backends/fs/riscos/riscos-fs-factory.h"
#elif defined(WIN32)
	#include "backends/fs/windows/windows-fs-factory.h"
#endif

class OSystem_NULL : public ModularMutexBackend, public ModularMixerBackend, public ModularGraphicsBackend, Common::EventSource {
public:
	OSystem_NULL();
	virtual ~OSystem_NULL();

	virtual void initBackend();

	virtual bool pollEvent(Common::Event &event);

	virtual uint32 getMillis(bool skipRecord = false);
	virtual void delayMillis(uint msecs);
	virtual void getTimeAndDate(TimeDate &t) const;

	virtual void quit();

	virtual void logMessage(LogMessageType::Type type, const char *message);

private:
#ifdef POSIX
	timeval _startTime;
#endif
};

OSystem_NULL::OSystem_NULL() {
	#if defined(__amigaos4__)
		_fsFactory = new AmigaOSFilesystemFactory();
	#elif defined(__MORPHOS__)	
		_fsFactory = new MorphOSFilesystemFactory();
	#elif defined(POSIX)
		_fsFactory = new POSIXFilesystemFactory();
	#elif defined(RISCOS)
		_fsFactory = new RISCOSFilesystemFactory();
	#elif defined(WIN32)
		_fsFactory = new WindowsFilesystemFactory();
	#else
		#error Unknown and unsupported FS backend
	#endif
}

OSystem_NULL::~OSystem_NULL() {
}

#ifdef POSIX
static volatile bool intReceived = false;

static sighandler_t last_handler;

void intHandler(int dummy) {
	signal(SIGINT, last_handler);
	intReceived = true;
}
#endif

void OSystem_NULL::initBackend() {
#ifdef POSIX
	gettimeofday(&_startTime, 0);

	last_handler = signal(SIGINT, intHandler);
#endif

	_mutexManager = new NullMutexManager();
	_timerManager = new DefaultTimerManager();
	_eventManager = new DefaultEventManager(this);
	_savefileManager = new DefaultSaveFileManager();
	_graphicsManager = new NullGraphicsManager();
	_mixerManager = new NullMixerManager();
	// Setup and start mixer
	_mixerManager->init();

	BaseBackend::initBackend();
}

bool OSystem_NULL::pollEvent(Common::Event &event) {
	((DefaultTimerManager *)getTimerManager())->checkTimers();
	((NullMixerManager *)_mixerManager)->update(1);

#ifdef POSIX
	if (intReceived) {
		intReceived = false;

#ifdef USE_TEXT_CONSOLE_FOR_DEBUGGER
		GUI::Debugger *debugger = g_engine ? g_engine->getOrCreateDebugger() : nullptr;
		if (debugger && !debugger->isActive()) {
			last_handler = signal(SIGINT, intHandler);
			event.type = Common::EVENT_DEBUGGER;
			return true;
		}
#endif

		event.type = Common::EVENT_QUIT;
		return true;
	}
#endif

	return false;
}

uint32 OSystem_NULL::getMillis(bool skipRecord) {
#ifdef POSIX
	timeval curTime;

	gettimeofday(&curTime, 0);

	return (uint32)(((curTime.tv_sec - _startTime.tv_sec) * 1000) +
			((curTime.tv_usec - _startTime.tv_usec) / 1000));
#else
	return 0;
#endif
}

void OSystem_NULL::delayMillis(uint msecs) {
#ifdef POSIX
	usleep(msecs * 1000);
#endif
}

void OSystem_NULL::getTimeAndDate(TimeDate &td) const {
	time_t curTime = time(0);
	struct tm t = *localtime(&curTime);
	td.tm_sec = t.tm_sec;
	td.tm_min = t.tm_min;
	td.tm_hour = t.tm_hour;
	td.tm_mday = t.tm_mday;
	td.tm_mon = t.tm_mon;
	td.tm_year = t.tm_year;
	td.tm_wday = t.tm_wday;
}

void OSystem_NULL::quit() {
	exit(0);
}

void OSystem_NULL::logMessage(LogMessageType::Type type, const char *message) {
	FILE *output = 0;

	if (type == LogMessageType::kInfo || type == LogMessageType::kDebug)
		output = stdout;
	else
		output = stderr;

	fputs(message, output);
	fflush(output);
}

OSystem *OSystem_NULL_create() {
	return new OSystem_NULL();
}

int main(int argc, char *argv[]) {
	g_system = OSystem_NULL_create();
	assert(g_system);

	// Invoke the actual ScummVM main entry point:
	int res = scummvm_main(argc, argv);
	g_system->destroy();
	return res;
}

#else /* USE_NULL_DRIVER */

OSystem *OSystem_NULL_create() {
	return NULL;
}

#endif