#include "quakedef.h"
# include <time.h>
#ifndef WIN32
# include <unistd.h>
# include <fcntl.h>
# include <dlfcn.h>
#endif

static char sys_timestring[128];
char *Sys_TimeString(const char *timeformat)
{
	time_t mytime = time(NULL);
	strftime(sys_timestring, sizeof(sys_timestring), timeformat, localtime(&mytime));
	return sys_timestring;
}


extern qboolean host_shuttingdown;
void Sys_Quit (int returnvalue)
{
	host_shuttingdown = true;
	Host_Shutdown();
	exit(returnvalue);
}

/*
===============================================================================

DLL MANAGEMENT

===============================================================================
*/

qboolean Sys_LoadLibrary (const char** dllnames, dllhandle_t* handle, const dllfunction_t *fcts)
{
	const dllfunction_t *func;
	dllhandle_t dllhandle = 0;
	unsigned int i;

	if (handle == NULL)
		return false;

#ifndef WIN32
#ifdef PREFER_PRELOAD
	dllhandle = dlopen(NULL, RTLD_LAZY | RTLD_GLOBAL);
	if(dllhandle)
	{
		for (func = fcts; func && func->name != NULL; func++)
			if (!(*func->funcvariable = (void *) Sys_GetProcAddress (dllhandle, func->name)))
			{
				dlclose(dllhandle);
				goto notfound;
			}
		Con_Printf ("All of %s's functions were already linked in! Not loading dynamically...\n", dllnames[0]);
		*handle = dllhandle;
		return true;
	}
notfound:
#endif
#endif

	// Initializations
	for (func = fcts; func && func->name != NULL; func++)
		*func->funcvariable = NULL;

	// Try every possible name
	Con_Printf ("Trying to load library...");
	for (i = 0; dllnames[i] != NULL; i++)
	{
		Con_Printf (" \"%s\"", dllnames[i]);
#ifdef WIN32
		dllhandle = LoadLibrary (dllnames[i]);
#else
		dllhandle = dlopen (dllnames[i], RTLD_LAZY | RTLD_GLOBAL);
#endif
		if (dllhandle)
			break;
	}

	// see if the names can be loaded relative to the executable path
	// (this is for Mac OSX which does not check next to the executable)
	if (!dllhandle && strrchr(com_argv[0], '/'))
	{
		char path[MAX_OSPATH];
		strlcpy(path, com_argv[0], sizeof(path));
		strrchr(path, '/')[1] = 0;
		for (i = 0; dllnames[i] != NULL; i++)
		{
			char temp[MAX_OSPATH];
			strlcpy(temp, path, sizeof(temp));
			strlcat(temp, dllnames[i], sizeof(temp));
			Con_Printf (" \"%s\"", temp);
#ifdef WIN32
			dllhandle = LoadLibrary (temp);
#else
			dllhandle = dlopen (temp, RTLD_LAZY | RTLD_GLOBAL);
#endif
			if (dllhandle)
				break;
		}
	}

	// No DLL found
	if (! dllhandle)
	{
		Con_Printf(" - failed.\n");
		return false;
	}

	Con_Printf(" - loaded.\n");

	// Get the function adresses
	for (func = fcts; func && func->name != NULL; func++)
		if (!(*func->funcvariable = (void *) Sys_GetProcAddress (dllhandle, func->name)))
		{
			Con_Printf ("Missing function \"%s\" - broken library!\n", func->name);
			Sys_UnloadLibrary (&dllhandle);
			return false;
		}

	*handle = dllhandle;
	return true;
}

void Sys_UnloadLibrary (dllhandle_t* handle)
{
	if (handle == NULL || *handle == NULL)
		return;

#ifdef WIN32
	FreeLibrary (*handle);
#else
	dlclose (*handle);
#endif

	*handle = NULL;
}

void* Sys_GetProcAddress (dllhandle_t handle, const char* name)
{
#ifdef WIN32
	return (void *)GetProcAddress (handle, name);
#else
	return (void *)dlsym (handle, name);
#endif
}