/*
 *  wslua_util.c
 *
 * (c) 2006, Luis E. Garcia Ontanon <luis@ontanon.org>
 *
 * $Id: wslua_util.c 48337 2013-03-16 08:12:29Z etxrab $
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * 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 "config.h"

/* WSLUA_MODULE Utility Utility Functions */

#include "wslua.h"
#include <math.h>
#include <epan/stat_cmd_args.h>

WSLUA_API gboolean wslua_optbool(lua_State* L, int n, gboolean def) {
	gboolean val = FALSE;

	if ( lua_isboolean(L,n) ) {
		val = lua_toboolean(L,n);
	} else if ( lua_isnil(L,n) || lua_gettop(L) < n ){
		val = def;
	} else {
		luaL_argerror(L,n,"must be a boolean");
	}

	return val;
}


WSLUA_API const gchar* lua_shiftstring(lua_State* L, int i) {
    const gchar* p = luaL_checkstring(L, i);

    if (p) {
        lua_remove(L,i);
        return p;
    } else {
        return NULL;
    }
}

/* following is based on the luaL_setfuncs() from Lua 5.2, so we can use it in pre-5.2 */
WSLUA_API void wslua_setfuncs(lua_State *L, const luaL_Reg *l, int nup) {
  luaL_checkstack(L, nup, "too many upvalues");
  for (; l->name != NULL; l++) {  /* fill the table with given functions */
    int i;
    for (i = 0; i < nup; i++)  /* copy upvalues to the top */
      lua_pushvalue(L, -nup);
    lua_pushcclosure(L, l->func, nup);  /* closure with those upvalues */
    lua_setfield(L, -(nup + 2), l->name);
  }
  lua_pop(L, nup);  /* remove upvalues */
}

WSLUA_FUNCTION wslua_get_version(lua_State* L) { /* Get Wireshark version */
    const gchar* str = VERSION;
    lua_pushstring(L,str);
    WSLUA_RETURN(1); /* version string */
}

WSLUA_FUNCTION wslua_format_date(lua_State* LS) { /* Formats an absolute timestamp into a human readable date */
#define WSLUA_ARG_format_date_TIMESTAMP 1 /* A timestamp value to convert. */
	lua_Number timestamp = luaL_checknumber(LS,WSLUA_ARG_format_date_TIMESTAMP);
	nstime_t then;
	gchar* str;

	then.secs = (guint32)floor(timestamp);
	then.nsecs = (guint32) ( (timestamp-(double)(then.secs))*1000000000);
	str = abs_time_to_str(&then, ABSOLUTE_TIME_LOCAL, TRUE);
	lua_pushstring(LS,str);

	WSLUA_RETURN(1); /* A string with the formated date */
}

WSLUA_FUNCTION wslua_format_time(lua_State* LS) { /* Formats a relative timestamp in a human readable form */
#define WSLUA_ARG_format_time_TIMESTAMP 1 /* A timestamp value to convert */
	lua_Number timestamp = luaL_checknumber(LS,WSLUA_ARG_format_time_TIMESTAMP);
	nstime_t then;
	gchar* str;

	then.secs = (guint32)floor(timestamp);
	then.nsecs = (guint32) ( (timestamp-(double)(then.secs))*1000000000);
	str = rel_time_to_str(&then);
	lua_pushstring(LS,str);

	WSLUA_RETURN(1); /* A string with the formated time */
}

WSLUA_FUNCTION wslua_report_failure(lua_State* LS) { /* Reports a failure to the user */
#define WSLUA_ARG_report_failure_TEXT 1 /* Message */
	const gchar* s = luaL_checkstring(LS,WSLUA_ARG_report_failure_TEXT);
	report_failure("%s",s);
	return 0;
}

static int wslua_log(lua_State* L, GLogLevelFlags log_level) {
    GString* str = g_string_new("");
    int n = lua_gettop(L);  /* Number of arguments */
    int i;

    lua_getglobal(L, "tostring");
    for (i=1; i<=n; i++) {
        const char *s;
        lua_pushvalue(L, -1);  /* function to be called */
        lua_pushvalue(L, i);   /* value to print */
        lua_call(L, 1, 1);
        s = lua_tostring(L, -1);  /* get result */
        if (s == NULL)
            return luaL_error(L, "`tostring' must return a string");

        if (i>1) g_string_append(str,"\t");
        g_string_append(str,s);

        lua_pop(L, 1);  /* pop result */
    }

    g_log(LOG_DOMAIN_LUA, log_level, "%s\n", str->str);
    g_string_free(str,TRUE);

    return 0;
}

WSLUA_FUNCTION wslua_critical( lua_State* L ) { /* Will add a log entry with critical severity*/
/* WSLUA_MOREARGS critical objects to be printed	*/
	wslua_log(L,G_LOG_LEVEL_CRITICAL);
	return 0;
}
WSLUA_FUNCTION wslua_warn( lua_State* L ) { /* Will add a log entry with warn severity */
/* WSLUA_MOREARGS warn objects to be printed	*/
	wslua_log(L,G_LOG_LEVEL_WARNING);
	return 0;
}
WSLUA_FUNCTION wslua_message( lua_State* L ) { /* Will add a log entry with message severity */
/* WSLUA_MOREARGS message objects to be printed	*/
	wslua_log(L,G_LOG_LEVEL_MESSAGE);
	return 0;
}
WSLUA_FUNCTION wslua_info( lua_State* L ) { /* Will add a log entry with info severity */
/* WSLUA_MOREARGS info objects to be printed	*/
	wslua_log(L,G_LOG_LEVEL_INFO);
	return 0;
}
WSLUA_FUNCTION wslua_debug( lua_State* L ) { /* Will add a log entry with debug severity */
/* WSLUA_MOREARGS debug objects to be printed	*/
	wslua_log(L,G_LOG_LEVEL_DEBUG);
	return 0;
}

/* The returned filename is g_malloc()'d so the caller must free it */
/* except when NULL is returned if file doesn't exist               */
static char* wslua_get_actual_filename(const char* fname) {
	char fname_clean[256];
	char* f;
	char* filename;

	g_strlcpy(fname_clean,fname,255);
	fname_clean[255] = '\0';

	for(f = fname_clean; *f; f++) {
		switch(*f) {
			case '/': case '\\':
				*f = *(G_DIR_SEPARATOR_S);
				break;
			default:
				break;
		}
	}

	if ( file_exists(fname_clean) ) {
		return g_strdup(fname_clean);
	}

	filename = get_persconffile_path(fname_clean,FALSE,FALSE);

	if ( file_exists(filename) ) {
		return filename;
	}
	g_free(filename);

	filename = get_datafile_path(fname_clean);
	if ( file_exists(filename) ) {
		return filename;
	}
	g_free(filename);

	return NULL;
}

WSLUA_FUNCTION wslua_loadfile(lua_State* L) {
	/* Lua's loadfile() has been modified so that if a file does not exist
	in the current directory it will look for it in wireshark's user and system directories */
#define WSLUA_ARG_loadfile_FILENAME 1 /* Name of the file to be loaded */
	const char *given_fname = luaL_checkstring(L, WSLUA_ARG_loadfile_FILENAME);
	char* filename;

	filename = wslua_get_actual_filename(given_fname);

	if (!filename) WSLUA_ARG_ERROR(loadfile,FILENAME,"file does not exist");

	if (luaL_loadfile(L, filename) == 0) {
		g_free(filename);
		return 1;
	} else {
		g_free(filename);
		lua_pushnil(L);
		lua_insert(L, -2);
		return 2;
	}
}

WSLUA_FUNCTION wslua_dofile(lua_State* L) {
	/* Lua's dofile() has been modified so that if a file does not exist
	in the current directory it will look for it in wireshark's user and system directories */
#define WSLUA_ARG_dofile_FILENAME 1 /* Name of the file to be run */
	const char *given_fname = luaL_checkstring(L, WSLUA_ARG_dofile_FILENAME);
	char* filename;
	int n;

	if (!given_fname) WSLUA_ARG_ERROR(dofile,FILENAME,"must be a string");

	filename = wslua_get_actual_filename(given_fname);

	if (!filename)  WSLUA_ARG_ERROR(dofile,FILENAME,"file does not exist");

	n = lua_gettop(L);
	if (luaL_loadfile(L, filename) != 0) lua_error(L);
	g_free(filename);
	lua_call(L, 0, LUA_MULTRET);
	return lua_gettop(L) - n;
}


WSLUA_FUNCTION wslua_persconffile_path(lua_State* L) {
#define WSLUA_OPTARG_persconffile_path_FILENAME 1 /* A filename */
	const char *fname = luaL_optstring(L, WSLUA_OPTARG_persconffile_path_FILENAME,"");
	char* filename = get_persconffile_path(fname,FALSE,FALSE);

	lua_pushstring(L,filename);
	g_free(filename);
	WSLUA_RETURN(1); /* The full pathname for a file in the personal configuration directory */
}

WSLUA_FUNCTION wslua_datafile_path(lua_State* L) {
#define WSLUA_OPTARG_datafile_path_FILENAME 1 /* A filename */
	const char *fname = luaL_optstring(L, WSLUA_OPTARG_datafile_path_FILENAME,"");
	char* filename = get_datafile_path(fname);

	lua_pushstring(L,filename);
	g_free(filename);
	WSLUA_RETURN(1); /* The full pathname for a file in wireshark's configuration directory */
}


WSLUA_CLASS_DEFINE(Dir,NOP,NOP); /* A Directory */

WSLUA_CONSTRUCTOR Dir_open(lua_State* L) {
	/* Usage: for filename in Dir.open(path) do ... end */
#define WSLUA_ARG_Dir_open_PATHNAME 1 /* The pathname of the directory */
#define WSLUA_OPTARG_Dir_open_EXTENSION 2 /* If given, only file with this extension will be returned */

	const char* dirname = luaL_checkstring(L,WSLUA_ARG_Dir_open_PATHNAME);
	const char* extension = luaL_optstring(L,WSLUA_OPTARG_Dir_open_EXTENSION,NULL);
	Dir dir;
	char* dirname_clean;

	if (!dirname) WSLUA_ARG_ERROR(Dir_open,PATHNAME,"must be a string");

	dirname_clean = wslua_get_actual_filename(dirname);
	if (!dirname_clean) WSLUA_ARG_ERROR(Dir_open,PATHNAME,"directory does not exist");

	if (!test_for_directory(dirname_clean))  {
		g_free(dirname_clean);
		WSLUA_ARG_ERROR(Dir_open,PATHNAME, "must be a directory");
	}

	dir = (Dir)g_malloc(sizeof(struct _wslua_dir));
	dir->dir = OPENDIR_OP(dirname_clean);
	g_free(dirname_clean);
	dir->ext = extension ? g_strdup(extension) : NULL;
	dir->dummy = (GError **)g_malloc(sizeof(GError *));
	*(dir->dummy) = NULL;

	if (dir->dir == NULL) {
		g_free(dir->dummy);
		g_free(dir);

		WSLUA_ARG_ERROR(Dir_open,PATHNAME,"could not open directory");
	}

	pushDir(L,dir);
	WSLUA_RETURN(1); /* the Dir object */
}

WSLUA_METAMETHOD Dir__call(lua_State* L) {
	/* At every invocation will return one file (nil when done) */

	Dir dir = checkDir(L,1);
	const FILE_T* file;
	const gchar* filename;
	const char* ext;

	if (!dir) {
		luaL_argerror(L,1,"must be a Dir");
		return 0;
	}

	if (!dir->dir) {
		return 0;
	}

	if ( ! ( file = DIRGETNEXT_OP(dir->dir ) )) {
		CLOSEDIR_OP(dir->dir);
		dir->dir = NULL;
		return 0;
	}


	if ( ! dir->ext ) {
		filename = GETFNAME_OP(file);
		lua_pushstring(L,filename);
		return 1;
	}

	do {
		filename = GETFNAME_OP(file);

		/* XXX strstr returns ptr to first match,
			this fails ext=".xxx" filename="aaa.xxxz.xxx"  */
		if ( ( ext = strstr(filename,dir->ext)) && g_str_equal(ext,dir->ext) ) {
			lua_pushstring(L,filename);
			return 1;
		}
	} while(( file = DIRGETNEXT_OP(dir->dir) ));

	CLOSEDIR_OP(dir->dir);
	dir->dir = NULL;
	return 0;
}

WSLUA_METHOD Dir_close(lua_State* L) {
	/* Closes the directory */
	Dir dir = checkDir(L,1);

	if (dir->dir) {
		CLOSEDIR_OP(dir->dir);
		dir->dir = NULL;
	}

	return 0;
}

/* Gets registered as metamethod automatically by WSLUA_REGISTER_CLASS/META */
static int Dir__gc(lua_State* L) {
	Dir dir = checkDir(L,1);

	if (dir->dir) {
		CLOSEDIR_OP(dir->dir);
	}

	g_free(dir->dummy);

	if (dir->ext) g_free(dir->ext);

	g_free(dir);

	return 0;
}

static const luaL_Reg Dir_methods[] = {
    {"open", Dir_open},
    {"close", Dir_close},
    { NULL, NULL }
};

static const luaL_Reg Dir_meta[] = {
    {"__call", Dir__call},
    { NULL, NULL }
};

int Dir_register(lua_State* L) {

    WSLUA_REGISTER_CLASS(Dir);

    return 1;
}


typedef struct _statcmd_t {
	lua_State* L;
	int func_ref;
} statcmd_t;

static int statcmd_init_cb_error_handler(lua_State* L _U_) {
	return 0;
}

static void statcmd_init(const char *optarg, void* userdata) {
    statcmd_t* sc = (statcmd_t *)userdata;
    lua_State* L = sc->L;

    lua_settop(L,0);
    lua_pushcfunction(L,statcmd_init_cb_error_handler);
    lua_rawgeti(L, LUA_REGISTRYINDEX, sc->func_ref);

	lua_pushstring(L,optarg);

    switch ( lua_pcall(L,1,0,1) ) {
        case 0:
            break;
        case LUA_ERRRUN:
            g_warning("Runtime error while calling statcmd callback");
            break;
        case LUA_ERRMEM:
            g_warning("Memory alloc error while calling statcmd callback");
            break;
        default:
            g_assert_not_reached();
            break;
    }

}

WSLUA_FUNCTION wslua_register_stat_cmd_arg(lua_State* L) {
	/*  Register a function to handle a -z option */
#define WSLUA_ARG_register_stat_cmd_arg_ARGUMENT 1 /* Argument */
#define WSLUA_OPTARG_register_stat_cmd_arg_ACTION 2 /* Action */
	const char* arg = luaL_checkstring(L,WSLUA_ARG_register_stat_cmd_arg_ARGUMENT);
	statcmd_t* sc = (statcmd_t *)g_malloc0(sizeof(statcmd_t)); /* XXX leaked */

	sc->L = L;
	lua_pushvalue(L, WSLUA_OPTARG_register_stat_cmd_arg_ACTION);
	sc->func_ref = luaL_ref(L, LUA_REGISTRYINDEX);
    lua_remove(L,1);

	register_stat_cmd_arg(arg, statcmd_init, sc);
	return 0;
}
