#include "global.h"
#include "ArchHooks_Unix.h"
#include "ProductInfo.h"
#include "RageLog.h"
#include "RageUtil.h"
#include "RageThreads.h"
#include "LocalizedString.h"
#include "SpecialFiles.h"
#include "archutils/Unix/SignalHandler.h"
#include "archutils/Unix/GetSysInfo.h"
#include "archutils/Common/PthreadHelpers.h"
#include "archutils/Unix/EmergencyShutdown.h"
#include "archutils/Unix/AssertionHandler.h"
#if defined(HAVE_UNISTD_H)
#include <unistd.h>
#endif
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>

#if defined(CRASH_HANDLER)
#include "archutils/Unix/CrashHandler.h"
#if defined(LINUX)
#include <limits.h>
#endif
#endif

#if defined(HAVE_FFMPEG)
extern "C"
{
	#include <libavcodec/avcodec.h>
}
#endif

#if defined(HAVE_X11)
#include "archutils/Unix/X11Helper.h"
#include <X11/Xlib.h>
#include <X11/Xatom.h>
#endif

static bool IsFatalSignal( int signal )
{
	switch( signal )
	{
	case SIGINT:
	case SIGTERM:
	case SIGHUP:
		return false;
	default:
		return true;
	}
}

static bool DoCleanShutdown( int signal, siginfo_t *si, const ucontext_t *uc )
{
	if( IsFatalSignal(signal) )
		return false;

	/* ^C. */
	ArchHooks::SetUserQuit();
	return true;
}

#if defined(CRASH_HANDLER)
static bool DoCrashSignalHandler( int signal, siginfo_t *si, const ucontext_t *uc )
{
        /* Don't dump a debug file if the user just hit ^C. */
	if( !IsFatalSignal(signal) )
		return true;

	CrashHandler::CrashSignalHandler( signal, si, uc );
	return false;
}
#endif

static bool EmergencyShutdown( int signal, siginfo_t *si, const ucontext_t *uc )
{
	if( !IsFatalSignal(signal) )
		return false;

	DoEmergencyShutdown();

#if defined(CRASH_HANDLER)
	/* If we ran the crash handler, then die. */
	kill( getpid(), SIGKILL );
#endif

	/* We didn't run the crash handler.  Run the default handler, so we can dump core. */
	return false;
}
	
#if defined(HAVE_TLS)
static thread_local int g_iTestTLS = 0;

static int TestTLSThread( void *p )
{
	g_iTestTLS = 2;
	return 0;
}

static void TestTLS()
{
#if defined(LINUX)
	/* TLS won't work on older threads libraries, and may crash. */
	if( !UsingNPTL() )
		return;
#endif
	/* TLS won't work on older Linux kernels.  Do a simple check. */
	g_iTestTLS = 1;

	RageThread TestThread;
	TestThread.SetName( "TestTLS" );
	TestThread.Create( TestTLSThread, nullptr );
	TestThread.Wait();

	if( g_iTestTLS == 1 )
		RageThread::SetSupportsTLS( true );
}
#endif

#if 1
/* If librt is available, use CLOCK_MONOTONIC to implement GetMicrosecondsSinceStart,
 * if supported, so changes to the system clock don't cause problems. */
namespace
{
	clockid_t g_Clock = CLOCK_REALTIME;
 
	void OpenGetTime()
	{
		static bool bInitialized = false;
		if( bInitialized )
			return;
		bInitialized = true;
 
		/* Check whether the clock is actually supported. */
		timespec ts;
		if( clock_getres(CLOCK_MONOTONIC, &ts) == -1 )
			return;

		/* If the resolution is worse than a millisecond, fall back on CLOCK_REALTIME. */
		if( ts.tv_sec > 0 || ts.tv_nsec > 1000000 )
			return;
		
		g_Clock = CLOCK_MONOTONIC;
	}
};

clockid_t ArchHooks_Unix::GetClock()
{
	OpenGetTime();
	return g_Clock;
}

int64_t ArchHooks::GetMicrosecondsSinceStart( bool bAccurate )
{
	OpenGetTime();

	timespec ts;
	clock_gettime( g_Clock, &ts );

	int64_t iRet = int64_t(ts.tv_sec) * 1000000 + int64_t(ts.tv_nsec)/1000;
	if( g_Clock != CLOCK_MONOTONIC )
		iRet = ArchHooks::FixupTimeIfBackwards( iRet );
	return iRet;
}
#else
int64_t ArchHooks::GetMicrosecondsSinceStart( bool bAccurate )
{
	struct timeval tv;
	gettimeofday( &tv, nullptr );

	int64_t iRet = int64_t(tv.tv_sec) * 1000000 + int64_t(tv.tv_usec);
	ret = FixupTimeIfBackwards( ret );
	return iRet;
}
#endif

RString ArchHooks::GetPreferredLanguage()
{
	RString locale;

	if (getenv("LANG"))
	{
		locale = getenv("LANG");
		RString region = locale.substr(3, 2);
		locale = locale.substr(0, 2);

		if (locale == "zh")
		{
			if (region == "CN" || region == "SG")
			{
				locale = "zh-Hans";
			}
			else if (region == "HK" || region == "TW")
			{
				locale = "zh-Hant";
			}
		}
	}
	else
	{
		LOG->Warn("Unable to determine system language. Using English.");
		locale = "en";
	}

	return locale;
}

void ArchHooks_Unix::Init()
{
	/* First, handle non-fatal termination signals. */
	SignalHandler::OnClose( DoCleanShutdown );

#if defined(CRASH_HANDLER)
	CrashHandler::CrashHandlerHandleArgs( g_argc, g_argv );
	CrashHandler::InitializeCrashHandler();
	SignalHandler::OnClose( DoCrashSignalHandler );
#endif

	/* Set up EmergencyShutdown, to try to shut down the window if we crash.
	 * This might blow up, so be sure to do it after the crash handler. */
	SignalHandler::OnClose( EmergencyShutdown );

	InstallExceptionHandler();
	
#if defined(HAVE_TLS) && !defined(BSD)
	TestTLS();
#endif
}

bool ArchHooks_Unix::GoToURL( RString sUrl )
{
	int status;
	pid_t p = fork();
	if ( p == -1 )
	{
		// Call to fork failed
		return false;
	}
	else if ( p == 0 )
	{
		// Child
		const char * const argv[] = { "xdg-open", sUrl.c_str(), nullptr };
		execv( "/usr/bin/xdg-open", const_cast<char * const *>( argv ));
		// If we reach here, the call to execvp failed
		exit( 1 );
	}
	else
	{
		// Parent
		waitpid( p, &status, 0 );
		return WEXITSTATUS( status ) == 0;
	}
}

#ifndef _CS_GNU_LIBC_VERSION
#define _CS_GNU_LIBC_VERSION 2
#endif

static RString LibcVersion()
{	
	char buf[1024] = "(error)";
	int ret = confstr( _CS_GNU_LIBC_VERSION, buf, sizeof(buf) );
	if( ret == -1 )
		return "(unknown)";

	return buf;
}

void ArchHooks_Unix::DumpDebugInfo()
{
	RString sys;
	int vers;
	GetKernel( sys, vers );
	LOG->Info( "OS: %s ver %06i", sys.c_str(), vers );

#if defined(CRASH_HANDLER)
	LOG->Info( "Crash backtrace component: %s", BACKTRACE_METHOD_TEXT );
	LOG->Info( "Crash lookup component: %s", BACKTRACE_LOOKUP_METHOD_TEXT );
#if defined(BACKTRACE_DEMANGLE_METHOD_TEXT)
	LOG->Info( "Crash demangle component: %s", BACKTRACE_DEMANGLE_METHOD_TEXT );
#endif
#endif

	LOG->Info( "Runtime library: %s", LibcVersion().c_str() );
	LOG->Info( "Threads library: %s", ThreadsVersion().c_str() );
#if defined(HAVE_FFMPEG)
	LOG->Info( "libavcodec: %#x (%u)", avcodec_version(), avcodec_version() );
#endif
}

void ArchHooks_Unix::SetTime( tm newtime )
{
	RString sCommand = ssprintf( "date %02d%02d%02d%02d%04d.%02d",
		newtime.tm_mon+1,
		newtime.tm_mday,
		newtime.tm_hour,
		newtime.tm_min,
		newtime.tm_year+1900,
		newtime.tm_sec );

	LOG->Trace( "executing '%s'", sCommand.c_str() ); 
	int ret = system( sCommand );
	if( ret == -1 || ret == 127 || !WIFEXITED(ret) || WEXITSTATUS(ret) )
		LOG->Trace( "'%s' failed", sCommand.c_str() );

	ret = system( "hwclock --systohc" );
	if( ret == -1 || ret == 127 || !WIFEXITED(ret) || WEXITSTATUS(ret) )
		LOG->Trace( "'hwclock --systohc' failed" );
}

RString ArchHooks_Unix::GetClipboard()
{
#ifdef HAVE_X11
	using namespace X11Helper;
	// Why isn't this defined by Xlib headers?
	Atom XA_CLIPBOARD = XInternAtom( Dpy, "CLIPBOARD", 0);
	Atom pstType;
	RString ret;
	unsigned char *paste;
	unsigned long remainder;
	int ck;
	Window selOwner;

	ASSERT( Win != None );
	// X11 is weird: instead of the clipboard being stored by the server
	// as you'd expect, it's actually a form of IPC, where we send
	// a request to the window we're pasting text from, and it sends
	// the paste data back.
	// XXX: X11 has TWO clipboards, the traditional Ctrl+C Ctrl+V,
	// and a second independent clipboard called the "primary selection",
	// set simply by selecting a span of text, and pasted with a
	// middle click. For now we just use the former, but this causes
	// problems in some cases because some (generally older) applications
	// only implement the latter.

	// Make sure someone has the clipboard first.
	selOwner = XGetSelectionOwner( Dpy, XA_CLIPBOARD );
	if( selOwner == None )
		// There is no clipboard right now.
		return "";

	// Tell the clipboard owner to give us the goods.
	// protip: XConvertSelection() puts the result of the request in a
	// property on YOUR window.
	XConvertSelection( Dpy, XA_CLIPBOARD, XA_STRING, XA_PRIMARY, Win, CurrentTime );
	// XXX: This seems to always return 1 even when it works. (Success == 0)
	
	// Now we must wait for the clipboard owner to cough it up.
	// HACK: What we SHOULD do is XSelectInput() for SelectionNotify before
	// calling XConvertSelection and then block on XWindowEvent(), but that
	// would require significant cooperation with InputHandler_X11 through
	// X11Helper.
	// TODO: Said cooperation would be useful as then LowLevelWindow_X11
	// could listen for XFocusInEvent / XFocusOutEvent and send those.
	XSync( Dpy, false );
	usleep( 10000 );

	// Now retrieve the paste from our primary selection property.
	// Delete our primary selection so we'll just have null next time.
	int unused2; // XXX: "actual format of the property"? What?
	unsigned long unused3;
	ck = XGetWindowProperty( Dpy, Win, XA_PRIMARY, 0, LONG_MAX, true, XA_STRING, &pstType, &unused2, &unused3, &remainder, &paste );
	if( ck != Success )
		// Selection doesn't exist
		return "";
	if( pstType != XA_STRING )
	{
		// Selection isn't stringable
		XFree(paste);
		return "";
	}

	ret = RString( (char*) paste);
	XFree(paste);
	return ret;
#else
	LOG->Warn("ArchHooks_Unix: GetClipboard(): Compiled without any supported clipboard source!");
	return "";
#endif
}

#include "RageFileManager.h"
#include <sys/stat.h>

static LocalizedString COULDNT_FIND_SONGS( "ArchHooks_Unix", "Couldn't find 'Songs'" );
void ArchHooks::MountInitialFilesystems( const RString &sDirOfExecutable )
{
	RString Root;
	struct stat st;
	if( !stat(sDirOfExecutable + "/Packages", &st) && st.st_mode&S_IFDIR )
		Root = sDirOfExecutable;
	else if( !stat(sDirOfExecutable + "/Songs", &st) && st.st_mode&S_IFDIR )
		Root = sDirOfExecutable;
	else if( !stat(RageFileManagerUtil::sInitialWorkingDirectory + "/Songs", &st) && st.st_mode&S_IFDIR )
		Root = RageFileManagerUtil::sInitialWorkingDirectory;
	else
		RageException::Throw( "%s", COULDNT_FIND_SONGS.GetValue().c_str() );

	FILEMAN->Mount( "dir", Root, "/" );
}

void ArchHooks::MountUserFilesystems( const RString &sDirOfExecutable )
{
	/* Path to write general mutable user data when not Portable
	 * Lowercase the PRODUCT_ID; dotfiles and directories are almost always lowercase.
	 */
	const char *szHome = getenv( "HOME" );
	RString sUserDataPath = ssprintf( "%s/.%s", szHome? szHome:".", "stepmania-5.1" ); //call an ambulance!
	FILEMAN->Mount( "dir", sUserDataPath + "/Announcers", "/Announcers" );
	FILEMAN->Mount( "dir", sUserDataPath + "/BGAnimations", "/BGAnimations" );
	FILEMAN->Mount( "dir", sUserDataPath + "/BackgroundEffects", "/BackgroundEffects" );
	FILEMAN->Mount( "dir", sUserDataPath + "/BackgroundTransitions", "/BackgroundTransitions" );
	FILEMAN->Mount( "dir", sUserDataPath + "/Cache", "/Cache" );
	FILEMAN->Mount( "dir", sUserDataPath + "/CDTitles", "/CDTitles" );
	FILEMAN->Mount( "dir", sUserDataPath + "/Characters", "/Characters" );
	FILEMAN->Mount( "dir", sUserDataPath + "/Courses", "/Courses" );
	FILEMAN->Mount( "dir", sUserDataPath + "/Logs", "/Logs" );
	FILEMAN->Mount( "dir", sUserDataPath + "/NoteSkins", "/NoteSkins" );
	FILEMAN->Mount( "dir", sUserDataPath + "/Packages", "/" + SpecialFiles::USER_PACKAGES_DIR );
	FILEMAN->Mount( "dir", sUserDataPath + "/Save", "/Save" );
	FILEMAN->Mount( "dir", sUserDataPath + "/Screenshots", "/Screenshots" );
	FILEMAN->Mount( "dir", sUserDataPath + "/Songs", "/Songs" );
	FILEMAN->Mount( "dir", sUserDataPath + "/RandomMovies", "/RandomMovies" );
	FILEMAN->Mount( "dir", sUserDataPath + "/Themes", "/Themes" );
}

/*
 * (c) 2003-2004 Glenn Maynard
 * All rights reserved.
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, and/or sell copies of the Software, and to permit persons to
 * whom the Software is furnished to do so, provided that the above
 * copyright notice(s) and this permission notice appear in all copies of
 * the Software and that both the above copyright notice(s) and this
 * permission notice appear in supporting documentation.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF
 * THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS
 * INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT
 * OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
 * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
 * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */