/**
 * @file
 *
 * Support routines for the apol program that are faster/easier when
 * written in C than in Tcl.
 *
 * @author Jeremy A. Mowery jmowery@tresys.com
 * @author Jason Tang  jtang@tresys.com
 *
 * Copyright (C) 2006-2007 Tresys Technology, LLC
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <config.h>

#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <tcl.h>

#include <apol/policy.h>
#include <sefs/db.hh>
#include <sefs/filesystem.hh>

/** severity of most recent message */
int msg_level = INT_MAX;

/** pointer to most recent message string */
char *message = NULL;

/**
 * Take the formated string, allocate space for it, and then write it
 * the policy's msg_callback_arg.  If there is already a string
 * stored, then append to the string if the message level is equal to
 * the previous one, overwrite the string if message level is less
 * than previous, else ignore the message.
 */
static void apol_tcl_common_route(void *arg, int level, const char *fmt, va_list ap)
{
	char *s, *t;
	Tcl_Interp *interp = static_cast < Tcl_Interp * >(arg);
	if (level == APOL_MSG_INFO && msg_level >= APOL_MSG_INFO)
	{
		/* generate an info event */
		free(message);
		message = NULL;
		if (vasprintf(&s, fmt, ap) < 0)
		{
			fprintf(stderr, "%s\n", strerror(errno));
			return;
		}
		message = s;
		msg_level = level;
		Tcl_Eval(interp, "Apol_Progress_Dialog::_update_message");
		while (Tcl_DoOneEvent(TCL_IDLE_EVENTS | TCL_DONT_WAIT)) ;
	}
	else if (message == NULL || level < msg_level)
	{
		/* overwrite the existing stored message string with a
		 * new, higher priority message */
		free(message);
		message = NULL;
		if (vasprintf(&s, fmt, ap) < 0)
		{
			fprintf(stderr, "%s\n", strerror(errno));
			return;
		}
		message = s;
		msg_level = level;
	}
	else if (level == msg_level)
	{
		/* append to existing error message */
		if (vasprintf(&s, fmt, ap) < 0)
		{
			fprintf(stderr, "%s\n", strerror(errno));
			return;
		}
		if (asprintf(&t, "%s\n%s", message, s) < 0)
		{
			free(s);
			fprintf(stderr, "%s\n", strerror(errno));
			return;
		}
		free(s);
		free(message);
		message = t;
	}
}

void apol_tcl_clear_info_string(void)
{
	if (message != NULL)
	{
		free(message);
		message = NULL;
	}
	msg_level = INT_MAX;
}

void apol_tcl_route_apol_to_string(void *arg, const apol_policy_t * p
				   __attribute__ ((unused)), int level, const char *fmt, va_list ap)
{
	apol_tcl_common_route(arg, level, fmt, ap);
}

void apol_tcl_route_sefs_to_string(void *arg, const sefs_fclist * s
				   __attribute__ ((unused)), int level, const char *fmt, va_list ap)
{
	apol_tcl_common_route(arg, level, fmt, ap);
}

int apol_tcl_get_info_level(void)
{
	return msg_level;
}

char *apol_tcl_get_info_string(void)
{
	return message;
}

void apol_tcl_set_info_string(apol_policy_t * p, const char *s)
{
	INFO(p, "%s", s);
}